Identification of Antigenic Glycans from Schistosoma mansoni by Using a Shotgun Egg Glycan Microarray.

PubMed

Mickum, Megan L; Prasanphanich, Nina Salinger; Song, Xuezheng; Dorabawila, Nelum; Mandalasi, Msano; Lasanajak, Yi; Luyai, Anthony; Secor, W Evan; Wilkins, Patricia P; Van Die, Irma; Smith, David F; Nyame, A Kwame; Cummings, Richard D; Rivera-Marrero, Carlos A

2016-05-01

Infection of mammals by the parasitic helminth Schistosoma mansoni induces antibodies to glycan antigens in worms and eggs, but the differential nature of the immune response among infected mammals is poorly understood. To better define these responses, we used a shotgun glycomics approach in which N-glycans from schistosome egg glycoproteins were prepared, derivatized, separated, and used to generate an egg shotgun glycan microarray. This array was interrogated with sera from infected mice, rhesus monkeys, and humans and with glycan-binding proteins and antibodies to gather information about the structures of antigenic glycans, which also were analyzed by mass spectrometry. A major glycan antigen targeted by IgG from different infected species is the FLDNF epitope [Fucα3GalNAcβ4(Fucα3)GlcNAc-R], which is also recognized by the IgG monoclonal antibody F2D2. The FLDNF antigen is expressed by all life stages of the parasite in mammalian hosts, and F2D2 can kill schistosomula in vitro in a complement-dependent manner. Different antisera also recognized other glycan determinants, including core β-xylose and highly fucosylated glycans. Thus, the natural shotgun glycan microarray of schistosome eggs is useful in identifying antigenic glycans and in developing new anti-glycan reagents that may have diagnostic applications and contribute to developing new vaccines against schistosomiasis. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Identification of Antigenic Glycans from Schistosoma mansoni by Using a Shotgun Egg Glycan Microarray

PubMed Central

Mickum, Megan L.; Prasanphanich, Nina Salinger; Song, Xuezheng; Dorabawila, Nelum; Mandalasi, Msano; Lasanajak, Yi; Luyai, Anthony; Secor, W. Evan; Wilkins, Patricia P.; Van Die, Irma; Smith, David F.; Nyame, A. Kwame

2016-01-01

Infection of mammals by the parasitic helminth Schistosoma mansoni induces antibodies to glycan antigens in worms and eggs, but the differential nature of the immune response among infected mammals is poorly understood. To better define these responses, we used a shotgun glycomics approach in which N-glycans from schistosome egg glycoproteins were prepared, derivatized, separated, and used to generate an egg shotgun glycan microarray. This array was interrogated with sera from infected mice, rhesus monkeys, and humans and with glycan-binding proteins and antibodies to gather information about the structures of antigenic glycans, which also were analyzed by mass spectrometry. A major glycan antigen targeted by IgG from different infected species is the FLDNF epitope [Fucα3GalNAcβ4(Fucα3)GlcNAc-R], which is also recognized by the IgG monoclonal antibody F2D2. The FLDNF antigen is expressed by all life stages of the parasite in mammalian hosts, and F2D2 can kill schistosomula in vitro in a complement-dependent manner. Different antisera also recognized other glycan determinants, including core β-xylose and highly fucosylated glycans. Thus, the natural shotgun glycan microarray of schistosome eggs is useful in identifying antigenic glycans and in developing new anti-glycan reagents that may have diagnostic applications and contribute to developing new vaccines against schistosomiasis. PMID:26883596

Is the Quantification of Antigen-Specific Basophil Activation a Useful Tool for Monitoring Oral Tolerance Induction in Children With Egg Allergy?

PubMed

Gamboa, P M; Garcia-Lirio, E; Gonzalez, C; Gonzalez, A; Martinez-Aranguren R M; Sanz María, L

2016-01-01

To assess modifications in baseline specific IgE- and anti-IgE- and antigen-specific-mediated basophil activation in egg-allergic children. The values were compared before and after the children completed specific oral tolerance induction (SOTI) with egg. We studied 28 egg-allergic children who completed SOTI with egg. The basophil activation test and specific IgE determinations with egg white, ovalbumin, and ovomucoid were performed in all 28 children. A decrease in antigen-specific activation with egg white, ovalbumin, and ovomucoid was observed only at the 2 lowest concentrations used (5 and 0.05 ng/mL). Baseline activation was higher in patients with multiple food allergies and in those who developed anaphylaxis during SOTI; this activation decreased in both groups after completion of SOTI. A significant decrease was also observed in specific IgE values for egg white, ovalbumin, and ovomucoid after tolerance induction. Food tolerance induction is a specific process for each food that can be mediated by immunologic changes such as a decrease in specific IgE values and in specific and spontaneous basophil activation.

Th1/Th2 balance and humoral immune response to potential antigens as early diagnostic method of equine Strongylus nematode infection.

PubMed

Abo-Aziza, Faten A M; Hendawy, Seham H M; Namaky, Amira H El; Ashry, Heba M

2017-06-01

The aim of this study was to investigate the early diagnosis of strongyle infection based on early changes in Th1 and Th2 cytokines beside the diagnostic accuracy values and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting profiles using prepared strongyles antigens. A total of 73 donkeys had a mean age of 4-32 years old were parasitologically examined for strongyle infection. The early changes in Th1 and Th2 cytokines were determined, and the diagnostic accuracy values and SDS-PAGE and western blotting profiles were performed using prepared strongyles antigens; crude somatic Strongylus vulgaris (CSS), excretory-secretory S. vulgaris (ESS), crude somatic Cyathostomins (CSC), and excretory-secretory Cyathostomins (ESC). The results revealed highest 437.04% and lowest 37.81% immunoglobulin G (IgG) in high and low egg shedder groups when using ESC and CSS antigens, respectively. Antibodies index for ESS and CSC were significantly higher in moderate egg shedder group while that for ESS and CSC, ESC was significantly higher in high egg shedder group. Tumor necrosis factor alpha (TNF-α)/interleukin-4 (IL-4) balance in S. vulgaris infected donkeys was approximately equal in apparently healthy, low and high egg shedder groups while TNF-α < IL-4 in moderate egg shedder. In Cyathostomins infected animals, TNF-α/IL-4 balance was approximately equal in apparently healthy group while it was low in moderate and high egg shedder groups. The diagnostic accuracy showed that the higher specificity (46.6%) and prevalence (95.40%) were recorded by CSS and ESC antigens, respectively. However, SDS-PAGE and western blotting profiling proved that the band at molecular weight 25 kDa is exhibited by CSS antigen. Combination of detecting level of TNF-α/IL-4 balance, CSS antigen and IgG concentration is good tool for appropriate diagnosis of such infection. More advancement research must be done concerning Th1/Th2 balance and cross-reactivity of S. vulgaris and Cyathostomins spp. at the base of serological and molecular investigation.

Th1/Th2 balance and humoral immune response to potential antigens as early diagnostic method of equine Strongylus nematode infection

PubMed Central

Abo-Aziza, Faten A. M.; Hendawy, Seham H. M.; Namaky, Amira H. El; Ashry, Heba M.

2017-01-01

Aim:: The aim of this study was to investigate the early diagnosis of strongyle infection based on early changes in Th1 and Th2 cytokines beside the diagnostic accuracy values and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting profiles using prepared strongyles antigens. Materials and Methods:: A total of 73 donkeys had a mean age of 4-32 years old were parasitologically examined for strongyle infection. The early changes in Th1 and Th2 cytokines were determined, and the diagnostic accuracy values and SDS-PAGE and western blotting profiles were performed using prepared strongyles antigens; crude somatic Strongylus vulgaris (CSS), excretory-secretory S. vulgaris (ESS), crude somatic Cyathostomins (CSC), and excretory-secretory Cyathostomins (ESC). Results:: The results revealed highest 437.04% and lowest 37.81% immunoglobulin G (IgG) in high and low egg shedder groups when using ESC and CSS antigens, respectively. Antibodies index for ESS and CSC were significantly higher in moderate egg shedder group while that for ESS and CSC, ESC was significantly higher in high egg shedder group. Tumor necrosis factor alpha (TNF-α)/interleukin-4 (IL-4) balance in S. vulgaris infected donkeys was approximately equal in apparently healthy, low and high egg shedder groups while TNF-α < IL-4 in moderate egg shedder. In Cyathostomins infected animals, TNF-α/IL-4 balance was approximately equal in apparently healthy group while it was low in moderate and high egg shedder groups. The diagnostic accuracy showed that the higher specificity (46.6%) and prevalence (95.40%) were recorded by CSS and ESC antigens, respectively. However, SDS-PAGE and western blotting profiling proved that the band at molecular weight 25 kDa is exhibited by CSS antigen. Conclusion:: Combination of detecting level of TNF-α/IL-4 balance, CSS antigen and IgG concentration is good tool for appropriate diagnosis of such infection. More advancement research must be done concerning Th1/Th2 balance and cross-reactivity of S. vulgaris and Cyathostomins spp. at the base of serological and molecular investigation. PMID:28717322

Response of amphibian egg non-yolk cytoplasm to gravity orientation

NASA Technical Reports Server (NTRS)

Smith, R. C.; Neff, A. W.; Malacinski, G. M.

1985-01-01

In order to study amphibian egg cytoplasmic organization and egg symmetrization at the molecular level, a library of seventeen monoclonal antibodies (MoAbs) against Xenopus laevis non-yolk egg proteins was produced. Several of these MoAbs react with non-yolk cytoplasmic antigens which are unevenly distributed in the fertile Xenopus egg.

Comparative studies on lecithin as a component of cardiolipin antigens

PubMed Central

Pontecorvo, M.; Rappaport, F.; Tompkins, V.; Vogelsang, T.

1955-01-01

Egg-yolk lecithin prepared as described in the second edition of of the WHO monograph on cardiolipin antigens was known to be satisfactory, but documentation was incomplete. In this paper, the authors discuss results of comparisons between egg-yolk lecithin and lecithin of beef-heart origin, carried out in four separate laboratories. PMID:13260890

PREVALENCE OF LYMPHATIC FILARIASIS, MALARIA AND SOIL TRANSMITTED HELMINTHIASIS IN A COMMUNITY OF BARDIYA DISTRICT, WESTERN NEPAL.

PubMed

Ranjitkar, Samir; Alifrangis, Michael; Adhikari, Madhav; Olsen, Annette; Simonsen, Paul E; Meyrowitsch, Dan Wolf

2014-11-01

Lymphatic filariasis (LF), malaria and soil transmitted helminthiasis (STH) cause major health problems in Nepal, but in spite of this very few stud- ies have been carried out on these parasitic infections in Nepal. A cross sectional survey of all three categories of parasitic infections was carried out in Deuda- kala Village of Bardiya District, western Nepal. A total of 510 individuals aged 5 years and above were examined from finger prick blood for circulating filarial antigen (CFA), malaria antigen using a rapid diagnostic test (RDT), and malaria DNA using a PCR-based assay. In addition, 317 individuals were examined for soil-transmitted helminth (STH) eggs by the Kato-Katz technique. Prevalence of LF, malaria (antigen) and STH infection was 25.1%, 0.6% and 18.3%, respectively. PCR analysis did not detect any additional malaria cases. The prevalence of LF and STH infections differ significantly among different age groups and ethnic communities. The high prevalence of LF in the community studied indicates an immediate need for implementing a mass drug administration program for its control in this particular geographical area of Nepal.

Effects of egg-adaptation on receptor-binding and antigenic properties of recent influenza A (H3N2) vaccine viruses.

PubMed

Parker, Lauren; Wharton, Stephen A; Martin, Stephen R; Cross, Karen; Lin, Yipu; Liu, Yan; Feizi, Ten; Daniels, Rodney S; McCauley, John W

2016-06-01

Influenza A virus (subtype H3N2) causes seasonal human influenza and is included as a component of influenza vaccines. The majority of vaccine viruses are isolated and propagated in eggs, which commonly results in amino acid substitutions in the haemagglutinin (HA) glycoprotein. These substitutions can affect virus receptor-binding and alter virus antigenicity, thereby, obfuscating the choice of egg-propagated viruses for development into candidate vaccine viruses. To evaluate the effects of egg-adaptive substitutions seen in H3N2 vaccine viruses on sialic acid receptor-binding, we carried out quantitative measurement of virus receptor-binding using surface biolayer interferometry with haemagglutination inhibition (HI) assays to correlate changes in receptor avidity with antigenic properties. Included in these studies was a panel of H3N2 viruses generated by reverse genetics containing substitutions seen in recent egg-propagated vaccine viruses and corresponding cell culture-propagated wild-type viruses. These assays provide a quantitative approach to investigating the importance of individual amino acid substitutions in influenza receptor-binding. Results show that viruses with egg-adaptive HA substitutions R156Q, S219Y, and I226N, have increased binding avidity to α2,3-linked receptor-analogues and decreased binding avidity to α2,6-linked receptor-analogues. No measurable binding was detected for the viruses with amino acid substitution combination 156Q+219Y and receptor-binding increased in viruses where egg-adaptation mutations were introduced into cell culture-propagated virus. Substitutions at positions 156 and 190 appeared to be primarily responsible for low reactivity in HI assays with post-infection ferret antisera raised against 2012-2013 season H3N2 viruses. Egg-adaptive substitutions at position 186 caused substantial differences in binding avidity with an insignificant effect on antigenicity.

In vitro production of Toxocara canis excretory-secretory (TES) antigen.

PubMed

Thomas, Divyamol; Jeyathilakan, N; Abdul Basith, S; Senthilkumar, T M A

2016-09-01

Toxocara canis is a widespread gastrointestinal nematode parasite of dogs and cause Toxocara larva migrans, an important zoonotic disease in humans on ingestion of infective eggs. Toxocarosis is one of the few human parasitic diseases whose serodiagnosis uses a standardized antigen, T. canis excretory secretory antigen (TES). The present study describes collection of T. canis adult worm, collection and embryonation of T. canis eggs, hatching and separation of T. canis larvae, in vitro maintenance of T. canis second stage larvae for production of TES, concentration of culture fluid TES and yield of TES in correlation with various methods cited in literature.

A review of biomarkers for predicting clinical reactivity to foods with a focus on specific immunoglobulin E antibodies.

PubMed

Sato, Sakura; Yanagida, Noriyuki; Ohtani, Kiyotaka; Koike, Yumi; Ebisawa, Motohiro

2015-06-01

The purpose of this study is to assess the latest studies that focus on specific immunoglobulin (Ig)E antibodies for predicting clinical reactivity to foods. Persistent hen's egg and cow's milk allergy patients have higher antigen-specific IgE levels at all ages than those who have outgrown these allergies. Recent studies on the natural histories of hen's egg and cow's milk allergies suggested that baseline antigen-specific IgEs are the most important predictors of tolerance. Oral immunotherapy (OIT), which is a novel therapeutic approach for food allergy, requires biomarkers for predicting outcomes after therapy. Several studies indicate that the initial antigen-specific IgE level may be a useful biomarker for the prognosis of OIT. Recently, component-resolved diagnostics (CRD) has been used for food allergy diagnosis. Current studies have suggested that Ara h 2, omega-5 gliadin and ovomucoid are good diagnostic markers for peanut, wheat and egg allergies, respectively. Antigen-specific IgE can be a useful biomarker for predicting clinical reactivity to food allergies. Monitoring hen's egg and cow's milk-specific IgE is useful for predicting prognosis, and baseline specific IgE levels may be associated with the outcome of OIT. The use of CRD provides us with a better tool for diagnosing food allergy.

[Studies on the intradermal reactions with the fractions of Ascaris lumbricoides

PubMed

Lee, Chan Wook

1967-06-01

INTRODUCTION : The studies on allergic reaction with the substances of Ascaris lumbricoides have long been studied by various worers; Conventry(1929), Campbell(1936), Sakei(1949), Miyakawa(1950), Ikeda(1952), Matsumoto and Imawari(1952), Morishita and Kobayashi(1953, 1954), Komiyayama(1954) and Yammoto(1956). Campbell(1936) and some other workers reported that the polysaccharides from ascaris produced the stronger intrademal reactions than protein fraction, though Yamamoto(1954) and others found the reverse results. On the other hand, Hosotani(1954) reported that the crude antigen or mixed antigen with polysaccharide and protein fraction of the ascaris produced the strongest skin reaction than with the other single fraction. As are shown in above reports, the intensity of the allergic reaction with the substances from ascaris is still remained under dipute. The reason might be due to the difference of the method of preparation, technique and evaluation. The aim of the present study is to elucidate the intensity of allergic reactivity fo protein and polysaccharide fration and mixed substance of two fractions and crude antigen of Ascaris lumbricoides. MATERIALS AND METHODS : A Intrdermal Test 1. Human Experiment. The intradermal test was performed on several groups of people. A: Ascaris lumbricoides egg positive cases among adult ages. B: Ascaris lumbricoides egg negative cases but who bad doubtful symptom. C: Ascaris lumbricoides egg negative cases but who had past history of ascaris infection. D: Ascaris lumbricoides egg negative cases and aged 3-8 months old. 2. Animal Experiment: Same breeds of 6 dogs were raised i cages of laboratory for 6 months, During the period, special attention was paid to keep them in parasite free conditon. The body weight was 10kg in average. B. Antigens. The adults worms of Ascaris lumbricoides, which were obtained during laparotomy, were first washed with sterilized saline solution. Each ascaris was placed in 50ml of saline solution and kept in 30 degrees C incubator for 24 hours. Among of them, the active one was seleted and put to sudden freeze at -70 degrees C for 20 hours. the whole body was powdered in a dried condition and kept it in ampoule at -4 degrees C. a) Crude antigen: The ether extract of powdered Ascaris lumbrucoides were motared by adding veronal buffer solution (1:100) and kept in icebox for 48 hours. The suspension was diluted with veronal buffer solution in the ratio of 1:10,000. b) Protein antigen : This antigen was prepared by Chaffee's modified methods and ammonium sulfate extraction mehtod. c) Polysaccharide antigen: Chaffee's modified method and ethanol extration method were applied. d) Mixed antigen : The same amount of preparation of protein and polysaccharide antigen were mixed. C. Intrdermal test 1. The intradermal test : 0.02ml of natigen was injected on the anterior surface of the frearm in human and on the back in aninmal, with tuberculin syringe. The criteria of the skin reaction were determined as follows; wheal: -; 0-4mm, +/-; 5-7mm, +;8-9mm, +; 21-32mm, ++; 33-44mm, +++; 45-56mm, ++++; over 57mm, in diameter. D. Stool examination : All the stool examination was done by formalin-ether concectration(M.G.L) method. E.P.G (egg per gram) was also determined by Stoll's egg counting method. RESULT : The intradermal reaction after the injection of each antigen was observed at 15, 30, 60 minutes and 3, 24 hours. In 58 ascariasis cases, the peak of wheal was appeared at 30 minute; 93.0% with the crude antigen, 15.5% with the mixed antigen, 10.3% with the Protein antigen, but all were negative in the polysaccharide antigen. The erythema reaction paralledled, in general, to the wheal; 75.8% at 15 minutes, 72.5% at 30 minutes and 48.3% at 60 mintues, with the crude antigen. Only 3.4% showed erythema at 15,30, and 60 minutes int the case of mixed antigen, and 1.7% fo positive was appeared at 30 minutes in the case of protein antigen, but none was observed in the polysaccharide antigen. The wheal and erythema revealed correlationship each other. Both of them showed 65.5% positive boundary in the case of crude antigen. Generally, the crude antigen resulted the highest and strongest reaction than the other fractions; the mixed, protein and polysaccharide in decreasing order. In adult age group, who showed egg negative at the time of injection, 81.5% were positive in skin reaction with the crude antigen, and 88.6% in the group who complained doubtful symptom but egg negative. In the group who had past history of ascaris infection showed 66.6% positive and the egg negative infant group with the same crude antigen. The sheal size was not always paralleled with the worm burden. The cross reaction with the antigen from Ascaris lumbricoides and Toxocara canis was examined by the intradermal test. There was no cross reaction between the two antigen. The infected dog with Toxocara canis showed positive reaction by the crude antigen of same species, but mot by the human species. Experimentally, the positive skin reaction was appeared only by the crude antigen at four weeks after the infection of Toxocara canis. CONCLUSION: The intradermal studies with the fraction of Ascaris lumbricoides and Toxocara canis were performed to human and dog, and the following results were observed. 1) Wheal and erythema were appeared in the cases of ascaris infection or who had past history, but not in the ascaris free before. 2) The size of wheal reached to peak 30 minutes after the injection. 3) The crude antigen had specificity and showed no cross reaction. 4) The crude antigen cause the strongest and largest reaction than the other substances; protein, polysaccharide and the mixed antigen. No cutaneous reaction was observed with the fraction of polysaccharides. 5) The size of wheal did not parallel with the worm burden. 6) The skin reaction was appeared four weeks after the infection.

Selecting accurate post-elimination monitoring tools to prevent reemergence of urogenital schistosomiasis in Morocco: a pilot study.

PubMed

Balahbib, Abdelaali; Amarir, Fatima; Corstjens, Paul L A M; de Dood, Claudia J; van Dam, Govert J; Hajli, Amina; Belhaddad, Meryem; El Mansouri, Bouchra; Sadak, Abderrahim; Rhajaoui, Mohamed; Adlaoui, El Bachir

2017-04-06

After alleged stop of transmission of schistosomiasis and further down the line in post elimination settings, sensitive tools are required to monitor infection status to prevent potential re-emergence. In Rahala, where transmission cycle of Schistosoma haematobium is interrupted since 2004 but where 30% of snails are still infected by S. bovis, potential human S. bovis infection can't be excluded. As methods based on egg-counts do not provide the required sensitivity, antibody or antigen assays are envisaged as the most appropriate tools for this type of monitoring. In this pilot study, the performances of three assays were compared: two commercially available antibody tests (ELISA and haemagglutination format) indicating exposure, and an antigen test (lateral flow strip format) demonstrating active infection. All 37 recruited study participants resided in Rahala (Akka, province Tata, Morocco). Participants had been diagnosed and cured from schistosomiasis in the period between 1983 and 2003. In 2015 these asymptomatic participants provided fresh clinical samples (blood and urine) for analysis with the aforementioned diagnostics tests. No eggs were identified in the urine of the 37 participants. The haemagglutination test indicated 6 antibody positives whereas the ELISA indicated 28 antibody positives, one indecisive and one false positive. ELISA and haemagglutination results matched for 18 individuals, amongst which 5 out of 6 haemagglutination positives. With the antigen test (performed on paired serum and urine samples), serum from two participants (cured 21 and 32 years ago) indicated the presence of low levels of the highly specific Schistosoma circulating anodic antigen (CAA), demonstrating low worm level infections (less than 5 pg/ml corresponding to probably single worm pair). One tested also CAA positive with urine. ELISA indicated the presence of human anti-Schistosoma antibodies in these two CAA positive cases, haemagglutination results were negative. To prevent reemergence of schistosomiasis in Morocco current monitoring programs require specific protocols that include testing of antibody positives for active infection by the UCP-LF CAA test, the appropriate diagnostic tool to identify Schistosoma low grade infections in travelers, immigrants and assumed cured cases. The test is genus specific will also identify infections related to S. bovis.

Antigenic Variation of Clade 2.1 H5N1 Virus Is Determined by a Few Amino Acid Substitutions Immediately Adjacent to the Receptor Binding Site

PubMed Central

Koel, Björn F.; van der Vliet, Stefan; Burke, David F.; Bestebroer, Theo M.; Bharoto, Eny E.; Yasa, I. Wayan W.; Herliana, Inna; Laksono, Brigitta M.; Xu, Kemin; Skepner, Eugene; Russell, Colin A.; Rimmelzwaan, Guus F.; Perez, Daniel R.; Osterhaus, Albert D. M. E.; Smith, Derek J.; Prajitno, Teguh Y.

2014-01-01

ABSTRACT Highly pathogenic avian influenza (HPAI) viruses of the H5N1 subtype are genetically highly variable and have diversified into multiple phylogenetic clades over the past decade. Antigenic drift is a well-studied phenomenon for seasonal human influenza viruses, but much less is known about the antigenic evolution of HPAI H5N1 viruses that circulate in poultry. In this study, we focused on HPAI H5N1 viruses that are enzootic to Indonesia. We selected representative viruses from genetically distinct lineages that are currently circulating and determined their antigenic properties by hemagglutination inhibition assays. At least six antigenic variants have circulated between 2003, when H5N1 clade 2.1 viruses were first detected in Indonesia, and 2011. During this period, multiple antigenic variants cocirculated in the same geographic regions. Mutant viruses were constructed by site-directed mutagenesis to represent each of the circulating antigenic variants, revealing that antigenic differences between clade 2.1 viruses were due to only one or very few amino acid substitutions immediately adjacent to the receptor binding site. Antigenic variants of H5N1 virus evaded recognition by both ferret and chicken antibodies. The molecular basis for antigenic change in clade 2.1 viruses closely resembled that of seasonal human influenza viruses, indicating that the hemagglutinin of influenza viruses from different hosts and subtypes may be similarly restricted to evade antibody recognition. PMID:24917596

Comparing in vitro lymphocyte reactivity to Salmonella enterica serovar Enteridis (SE) antigens 5 commercial white egg and 3 commercial brown egg strains of laying hens following SE infection.

USDA-ARS?s Scientific Manuscript database

Different chicken breeds have been shown to exhibit varying susceptibility to infection with paratyphoid salmonellae. The current study was undertaken to compare the course of infection with SE in crops and intestines of 5 commercial white egg strains (W1-W5) and 3 commercial brown egg strains (B1-...

Performance characteristics of qualified cell lines for isolation and propagation of influenza viruses for vaccine manufacturing

PubMed Central

Donis, Ruben O.; Chen, i-Mei; Davis, C Todd; Foust, Angie; Hossain, M. Jaber; Johnson, Adam; Klimov, Alexander; Loughlin, Rosette; Xu, Xiyan; Tsai, Theodore; Blayer, Simone; Trusheim, Heidi; Colegate, Tony; Fox, John; Taylor, Beverly; Hussain, Althaf; Barr, Ian; Baas, Chantal; Louwerens, Jaap; Geuns, Ed; Lee, Min-Shi; Venhuizen, odewijk; Neumeier, Elisabeth; Ziegler, Thedi

2018-01-01

Cell culture is now available as a method for the production of influenza vaccines in addition to eggs. In accordance with currently accepted practice, viruses recommended as candidates for vaccine manufacture are isolated and propagated exclusively in hens' eggs prior to distribution to manufacturers. Candidate vaccine viruses isolated in cell culture are not available to support vaccine manufacturing in mammalian cell bioreactors so egg-derived viruses have to be used. Recently influenza A (H3N2) viruses have been difficult to isolate directly in eggs. As mitigation against this difficulty, and the possibility of no suitable egg-isolated candidate viruses being available, it is proposed to consider using mammalian cell lines for primary isolation of influenza viruses as candidates for vaccine production in egg and cell platforms. To investigate this possibility, we tested the antigenic stability of viruses isolated and propagated in cell lines qualified for influenza vaccine manufacture and subsequently investigated antigen yields of such viruses in these cell lines at pilot-scale. Twenty influenza A and B-positive, original clinical specimens were inoculated in three MDCK cell lines. The antigenicity of recovered viruses was tested by hemagglutination inhibition using ferret sera against contemporary vaccine viruses and the amino acid sequences of the hemagglutinin and neuraminidase were determined. MDCK cell lines proved to be highly sensitive for virus isolation. Compared to the virus sequenced from the original specimen, viruses passaged three times in the MDCK lines showed up to 2 amino acid changes in the hemagglutinin. Antigenic stability was also established by hemagglutination inhibition titers comparable to those of the corresponding reference virus. Viruses isolated in any of the three MDCK lines grew reasonably well but variably in three MDCK cells and in VERO cells at pilot-scale. These results indicate that influenza viruses isolated in vaccine certified cell lines may well qualify for use in vaccine production. PMID:24975811

Performance characteristics of qualified cell lines for isolation and propagation of influenza viruses for vaccine manufacturing.

PubMed

Donis, Ruben O; Davis, C Todd; Foust, Angie; Hossain, M Jaber; Johnson, Adam; Klimov, Alexander; Loughlin, Rosette; Xu, Xiyan; Tsai, Theodore; Blayer, Simone; Trusheim, Heidi; Colegate, Tony; Fox, John; Taylor, Beverly; Hussain, Althaf; Barr, Ian; Baas, Chantal; Louwerens, Jaap; Geuns, Ed; Lee, Min-Shi; Venhuizen, Odewijk; Neumeier, Elisabeth; Ziegler, Thedi

2014-11-12

Cell culture is now available as a method for the production of influenza vaccines in addition to eggs. In accordance with currently accepted practice, viruses recommended as candidates for vaccine manufacture are isolated and propagated exclusively in hens' eggs prior to distribution to manufacturers. Candidate vaccine viruses isolated in cell culture are not available to support vaccine manufacturing in mammalian cell bioreactors so egg-derived viruses have to be used. Recently influenza A (H3N2) viruses have been difficult to isolate directly in eggs. As mitigation against this difficulty, and the possibility of no suitable egg-isolated candidate viruses being available, it is proposed to consider using mammalian cell lines for primary isolation of influenza viruses as candidates for vaccine production in egg and cell platforms. To investigate this possibility, we tested the antigenic stability of viruses isolated and propagated in cell lines qualified for influenza vaccine manufacture and subsequently investigated antigen yields of such viruses in these cell lines at pilot-scale. Twenty influenza A and B-positive, original clinical specimens were inoculated in three MDCK cell lines. The antigenicity of recovered viruses was tested by hemagglutination inhibition using ferret sera against contemporary vaccine viruses and the amino acid sequences of the hemagglutinin and neuraminidase were determined. MDCK cell lines proved to be highly sensitive for virus isolation. Compared to the virus sequenced from the original specimen, viruses passaged three times in the MDCK lines showed up to 2 amino acid changes in the hemagglutinin. Antigenic stability was also established by hemagglutination inhibition titers comparable to those of the corresponding reference virus. Viruses isolated in any of the three MDCK lines grew reasonably well but variably in three MDCK cells and in VERO cells at pilot-scale. These results indicate that influenza viruses isolated in vaccine certified cell lines may well qualify for use in vaccine production. Published by Elsevier Ltd.

Protection of ewes against Teladorsagia circumcincta infection in the periparturient period by vaccination with recombinant antigens.

PubMed

Nisbet, Alasdair J; McNeilly, Tom N; Greer, Andrew W; Bartley, Yvonne; Oliver, E Margaret; Smith, Stephen; Palarea-Albaladejo, Javier; Matthews, Jacqueline B

2016-09-15

Teladorsagiosis is a major production-limiting disease in ruminants in temperate regions throughout the world and one of the key interventions in the management of the disease is the prevention of pasture contamination with Teladorsagia circumcincta eggs by ewes during the periparturient relaxation in immunity which occurs in the period around lambing. Here, we describe the immunisation of twin-bearing ewes with a T. circumcincta recombinant subunit vaccine and the impact that vaccination has on their immune responses and shedding of parasite eggs during a continuous T. circumcincta challenge period spanning late gestation and lactation. In ewes which displayed a clear periparturient relaxation in immunity, vaccination resulted in a 45% reduction in mean cumulative faecal egg count (cFEC, p=0.027) compared to control (immunised with adjuvant only) ewes. Recombinant antigen-specific IgG and IgA, which bound each of the vaccine antigens, were detected in the serum of vaccinated ewes following each immunisation and in colostrum taken from vaccinated ewes post-partum whereas low levels of antigen-specific IgG were detected in serum and colostrum from control ewes. Antigen-specific IgG and IgA levels in blood collected within 48h of birth from lambs largely reflected those in the colostrum of their ewes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Cross-reactivity of Schistosoma mansoni-Fasciola gigantica influenced by saponins.

PubMed

Maghraby, Amany Sayed; Shaker, Kamel H; Gaber, Hanaa M

2009-01-01

The aim of the present work was to investigate the Schistosoma mansoni and Fasciola gigantica cross-reactivity between adult worms and egg homogenates of the parasites. Immunoprophylactic effects of crude Schistosoma mansoni worms and egg antigens mixed with or without saponins extracted from Atriplex nummularia were studied followed by challenge with 80 cercariae of Schistosoma mansoni. Our results showed that post 1st immunization with schistosome egg antigens (SEA) there was a significant change (P approximately 0.05) in the IgM levels against Fasciola egg homogenate (FgEH) without saponins. Post 2nd immunization with SEA mixed with saponins the levels of IgM increased significantly (P approximately 0.05) against Fasciola worm homogenate (FgWH) as compared with a non-immunized group. Post 2nd immunization the level of IgG was significantly elevated (P approximately 0.05) by SEA mixed with saponins against FgWH. Post 2nd immunizations with SEA mixed with saponins showed a significant change (P approximately 0.05) in IgG levels against FgEH. These results clearly demonstrated that there is a cross-reactivity between Schistosoma mansoni eggs and Fasciola gigantica worms and eggs. Saponins were found to be immunostimulatory adjuvants in our study.

Vaccination of calves against Taenia saginata infection using antigens collected during in vitro cultivation of larvae: passive protection via colostrum from vaccinated cows and vaccination of calves protected by maternal antibody.

PubMed

Rickard, M D; Adolph, A J; Arundel, J H

1977-11-01

Six-to-11-day-old calves which received colostrum from cows vaccinated with in vitro culture antigens of Taenia saginata during their last month of pregnancy showed a high level of resistance to a challenge infection with T saginata eggs. Although colostral antibody reduced the numbers of larvae which became established it did not promote destruction of those which had undergone development. Calves which had received colostrum from vaccinated dams were themselves vaccinated with culture antigen when they were eight to 10 weeks old. These calves showed strong immunity to a challenge infection of T saginata eggs administered four weeks after vaccination.

Antigenicity of the 2015-2016 seasonal H1N1 human influenza virus HA and NA proteins.

PubMed

Clark, Amelia M; DeDiego, Marta L; Anderson, Christopher S; Wang, Jiong; Yang, Hongmei; Nogales, Aitor; Martinez-Sobrido, Luis; Zand, Martin S; Sangster, Mark Y; Topham, David J

2017-01-01

Antigenic drift of the hemagglutinin (HA) and neuraminidase (NA) influenza virus proteins contributes to reduced vaccine efficacy. To analyze antigenic drift in human seasonal H1N1 viruses derived from the 2009 pandemic H1N1 virus (pH1N1-like viruses) accounts for the limited effectiveness (around 40%) of vaccination against pH1N1-like viruses during the 2015-2016 season, nasal washes/swabs collected from adult subjects in the Rochester, NY area, were used to sequence and isolate the circulating viruses. The HA and NA proteins from viruses circulating during the 2015-2016 season encoded eighteen and fourteen amino acid differences, respectively, when compared to A/California/04/2009, a strain circulating at the origin of the 2009 pandemic. The circulating strains belonged to subclade 6B.1, defined by HA amino acid substitutions S101N, S179N, and I233T. Hemagglutination-inhibiting (HAI) and HA-specific neutralizing serum antibody (Ab) titers from around 50% of pH1N1-like virus-infected subjects and immune ferrets were 2-4 fold lower for the 2015-2016 circulating strains compared to the vaccine strain. In addition, using a luminex-based mPlex HA assay, the binding of human sera from subjects infected with pH1N1-like viruses to the HA proteins from circulating and vaccine strains was not identical, strongly suggesting antigenic differences in the HA protein. Additionally, NA inhibition (NAI) Ab titers in human sera from pH1N1-like virus-infected subjects increased after the infection and there were measurable antigenic differences between the NA protein of circulating strains and the vaccine strain using both ferret and human antisera. Despite having been vaccinated, infected subjects exhibited low HAI Ab titers against the vaccine and circulating strains. This suggests that poor responses to the H1N1 component of the vaccine as well as antigenic differences in the HA and NA proteins of currently circulating pH1N1-like viruses could be contributing to risk of infection even after vaccination.

Antigenicity of the 2015–2016 seasonal H1N1 human influenza virus HA and NA proteins

PubMed Central

Anderson, Christopher S.; Wang, Jiong; Yang, Hongmei; Nogales, Aitor; Martinez-Sobrido, Luis; Zand, Martin S.; Sangster, Mark Y.; Topham, David J.

2017-01-01

Antigenic drift of the hemagglutinin (HA) and neuraminidase (NA) influenza virus proteins contributes to reduced vaccine efficacy. To analyze antigenic drift in human seasonal H1N1 viruses derived from the 2009 pandemic H1N1 virus (pH1N1-like viruses) accounts for the limited effectiveness (around 40%) of vaccination against pH1N1-like viruses during the 2015–2016 season, nasal washes/swabs collected from adult subjects in the Rochester, NY area, were used to sequence and isolate the circulating viruses. The HA and NA proteins from viruses circulating during the 2015–2016 season encoded eighteen and fourteen amino acid differences, respectively, when compared to A/California/04/2009, a strain circulating at the origin of the 2009 pandemic. The circulating strains belonged to subclade 6B.1, defined by HA amino acid substitutions S101N, S179N, and I233T. Hemagglutination-inhibiting (HAI) and HA-specific neutralizing serum antibody (Ab) titers from around 50% of pH1N1-like virus-infected subjects and immune ferrets were 2–4 fold lower for the 2015–2016 circulating strains compared to the vaccine strain. In addition, using a luminex-based mPlex HA assay, the binding of human sera from subjects infected with pH1N1-like viruses to the HA proteins from circulating and vaccine strains was not identical, strongly suggesting antigenic differences in the HA protein. Additionally, NA inhibition (NAI) Ab titers in human sera from pH1N1-like virus-infected subjects increased after the infection and there were measurable antigenic differences between the NA protein of circulating strains and the vaccine strain using both ferret and human antisera. Despite having been vaccinated, infected subjects exhibited low HAI Ab titers against the vaccine and circulating strains. This suggests that poor responses to the H1N1 component of the vaccine as well as antigenic differences in the HA and NA proteins of currently circulating pH1N1-like viruses could be contributing to risk of infection even after vaccination. PMID:29145498

Polyvalent heat-killed antigen for the diagnosis of infection with Legionella pneumophila.

PubMed Central

Fallon, R J; Abraham, W H

1982-01-01

A polyvalent antigen composed of heat-killed agar-grown Legionella pneumophila serogroups 1-4 suspended in a suspension of yolk-sac from embryonated hens' eggs has been examined for use in the indirect fluorescent antibody test for Legionella infection. The serological response detected by monovalent antigen correlated well with that detected by polyvalent antigen. The use of polyvalent antigen forms a useful screening test for the detection of antibody to L pneumophila, but positive results must be confirmed by test using monovalent antigen. PMID:7042762

Analysis of antigen conservation and inactivation of gamma-irradiated avian influenza virus subtype H9N2.

PubMed

Salehi, Bahareh; Motamedi-Sedeh, Farahnaz; Madadgar, Omid; Khalili, Iraj; Ghalyan Chi Langroudi, Arash; Unger, Hermann; Wijewardana, Viskam

2018-06-01

Avian influenza (AI) A subtype H9N2 virus belongs to Orthomyxoviridae family and causes low-pathogenic disease AI. The use of gamma-irradiated viral antigens has been developed in the production of effective vaccines. In this research, LPAIV H9N2 strain, A/Chicken/IRN/Ghazvin/2001, was multiplied on SPF eggs and irradiated by a Nordian gamma cell instrument. Irradiated and non-irradiated AI virus (AIV) samples were titrated by EID50 method and hemagglutinin (HA) antigen was analyzed by HA test as the WHO pattern method. Infectivity of irradiated virus was determined by egg inoculation method during four blind cultures. The results showed that after increasing the dose of gamma radiation, virus titer gradually decreased. D 10 value and optimum dose for complete virus inactivation were calculated by dose/response curve, 3.36 and 29.52 kGy, respectively. In addition, HA antigenicity of gamma-irradiated virus samples from 0 to 30 kGy was not changed. The results of safety test for gamma-irradiated AIV samples showed complete inactivation with gamma ray doses 30 and 35 kGy, without any multiplication on eggs after four blind cultures. According to the results of HA antigen assay and safety test, the gamma-irradiated and complete inactivated AIV subtype H9N2 is a good candidate as an inactivated immunogenic agent for poultry vaccination.

Antigenic and genomic characterization of human influenza A and B viruses circulating in Argentina after the introduction of influenza A(H1N1)pdm09.

PubMed

Russo, Mara L; Pontoriero, Andrea V; Benedetti, Estefania; Czech, Andrea; Avaro, Martin; Periolo, Natalia; Campos, Ana M; Savy, Vilma L; Baumeister, Elsa G

2014-12-01

This study was conducted as part of the Argentinean Influenza and other Respiratory Viruses Surveillance Network, in the context of the Global Influenza Surveillance carried out by the World Health Organization (WHO). The objective was to study the activity and the antigenic and genomic characteristics of circulating viruses for three consecutive seasons (2010, 2011 and 2012) in order to investigate the emergence of influenza viral variants. During the study period, influenza virus circulation was detected from January to December. Influenza A and B, and all current subtypes of human influenza viruses, were present each year. Throughout the 2010 post-pandemic season, influenza A(H1N1)pdm09, unexpectedly, almost disappeared. The haemagglutinin (HA) of the A(H1N1)pdm09 viruses studied were segregated in a different genetic group to those identified during the 2009 pandemic, although they were still antigenically closely related to the vaccine strain A/California/07/2009. Influenza A(H3N2) viruses were the predominant strains circulating during the 2011 season, accounting for nearly 76 % of influenza viruses identified. That year, all HA sequences of the A(H3N2) viruses tested fell into the A/Victoria/208/2009 genetic clade, but remained antigenically related to A/Perth/16/2009 (reference vaccine recommended for this three-year period). A(H3N2) viruses isolated in 2012 were antigenically closely related to A/Victoria/361/2011, recommended by the WHO as the H3 component for the 2013 Southern Hemisphere formulation. B viruses belonging to the B/Victoria lineage circulated in 2010. A mixed circulation of viral variants of both B/Victoria and B/Yamagata lineages was detected in 2012, with the former being predominant. A(H1N1)pdm09 viruses remained antigenically closely related to the vaccine virus A/California/7/2009; A(H3N2) viruses continually evolved into new antigenic clusters and both B lineages, B/Victoria/2/87-like and B/Yamagata/16/88-like viruses, were observed during the study period. The virological surveillance showed that the majority of the circulating strains during the study period were antigenically related to the corresponding Southern Hemisphere vaccine strains except for the 2012 A(H3N2) viruses. © 2014 The Authors.

[Denaturation of egg antigens by cooking].

PubMed

Watanabe, Hiroko; Akaboshi, Chie; Sekido, Haruko; Tanaka, Kouki; Tanaka, Kazuko; Shimojo, Naoki

2012-01-01

Changes in egg protein contents by cooking were measured with an ELISA kit using Tris-HCl buffer in model foods including cake, meatballs, pasta and pudding made with whole egg, egg-white and egg-yolk. The egg protein contents were lowest in the deep-fried model foods of cakes and meatballs. Ovalbumin (OVA) was undetectable (<1 µg/g) and ovomucoid (OVM) was lowest in pouched meatballs, suggesting that processing temperature and uniform heat-treatment affect the detection of egg protein. Furthermore, egg protein contents were below 6 µg/g in the pouched meatballs and pasta made with egg-yolk, and OVA and OVM were not detected by Western blotting analysis with human IgE from patients' serum. On the other hand, processed egg proteins were detected with an ELISA kit using a surfactant and reductant in the extract buffer.

Epizootiology of spirorchid infection in green turtles (Chelonia mydas) in Hawaii

USGS Publications Warehouse

Work, Thierry M.; Balazs, George H.; Schumacher, Jody L.; Marie, Amarisa

2005-01-01

We describe the epizootiology of spirorchiid trematode infections in Hawaiian green turtles (Chelonia mydas) by quantifying tissue egg burdens in turtles submitted for necropsy and by assessing antibody response to crude adult worm and egg antigens among a variety of age groups. Hapalotrema sp. and Laeredius sp. predominated in turtles infected with spirorchiids. Tissue egg burdens decreased with increasing size and increased with deteriorating body condition of turtles. No relationship was found between tissue egg burdens and sex or fibropapillomatosis status. Tissue egg burdens increased in turtles from southeast to northwest in the main Hawaiian Islands (Hawaii to Kauai). Hatchling and captive-reared turtles had significantly lower levels of antibodies against crude worm and egg antigens. Based on tissue egg burdens and antibody status, we hypothesize that immature turtles become infected with spirorchiids shortly after recruiting into coastal foraging pastures from the pelagic environment, that infection levels decrease with age, and that spirorchiids detrimentally affect the body condition of sea turtles independent of tumor burden. The low intensity of infection in turtles with the endemic trematode Carettacola hawaiiensis suggests either that turtles are less susceptible to infection with this parasite or that the parasite is outcompeted by species of Hapalotrema and Laeredius. Given that the 2 latter species are found in the Pacific and other oceans, they are not likely endemic and were probably introduced into Hawaii through an undetermined route.

Examining the relationships between egg cortisol and oxidative stress in developing wild sockeye salmon (Oncorhynchus nerka).

PubMed

Taylor, Jessica J; Sopinka, Natalie M; Wilson, Samantha M; Hinch, Scott G; Patterson, David A; Cooke, Steven J; Willmore, William G

2016-10-01

Maternally-derived hormones in oocytes, such as glucocorticoids (GCs), play a crucial role in embryo development in oviparous taxa. In fishes, maternal stressor exposure increases circulating and egg cortisol levels, the primary GC in fishes, as well as induces oxidative stress. Elevated egg cortisol levels modify offspring traits but whether maternal oxidative stress correlates with circulating and egg cortisol levels, and whether maternal/egg cortisol levels correlate with offspring oxidative stress have yet to be determined. The objective of this study was to examine the relationships among maternal and egg cortisol, and maternal and offspring oxidative stress to provide insight into the potential intergenerational effects of stressor exposure in sockeye salmon (Oncorhynchus nerka). Antioxidant concentration and oxidative stress were measured in maternal tissues (plasma, brain, heart and liver) as well as offspring developmental stages (pre-fertilization, 24h post-fertilization, eyed, and hatch), and were compared to both naturally-occurring and experimentally-elevated (via cortisol egg bath) levels of cortisol in eggs. Oxygen radical absorptive capacity of tissues from maternal sockeye salmon was measured spectrophotometrically and was not correlated with maternal or egg cortisol concentrations. Also, naturally-occurring and experimentally-elevated cortisol levels in eggs (to mimic maternal stress) did not affect oxidative stress or antioxidant capacity of the offspring. We conclude that the metrics of maternal stress examined in sockeye salmon (i.e., maternal/egg cortisol, maternal oxidative stress) are independent of each other, and that egg cortisol content does not influence offspring oxidative stress. Copyright © 2016 Elsevier Inc. All rights reserved.

Higher Frequency of Circulating PD-1high CXCR5+CD4+ Tfh Cells in Patients with Chronic Schistosomiasis

PubMed Central

Zhang, Yumei; Jiang, Yanyan; Wang, Yanjuan; Liu, Hua; Shen, Yujuan; Yuan, Zhongying; Hu, Yuan; Xu, Yuxin; Cao, Jianping

2015-01-01

The current knowledge of immunological responses to schistosomiasis is insufficient for the development of vaccine and therapies. The role of T follicular helper (Tfh) cells in schistosome infections is not fully defined. The frequency of circulating Tfh cells and serum cytokine levels were analyzed in 11 patients with chronic schistosomiasis and 10 healthy controls (HC), who reside in an endemic area for Schistosomiasis japonicum. Significantly higher frequencies of circulating CXCR5+ CD4+ Tfh cells and higher expression levels of ICOS and PD-1 in CXCR5+ CD4+ Tfh cells were observed in patients with chronic schistosomiasis compared to HC. The levels of IL-21 in serum and the expression of IL-21 mRNA were higher in chronic schistosomiasis patients than in HC. Moreover, the frequency of circulating PD-1high CXCR5+ CD4+ Tfh cells positively correlated with the levels of IL-21 in serum from patients with chronic schistosomiasis. A positive correlation was also found between the frequency of PD-1high CXCR5+ CD4+ Tfh cells and the levels of soluble egg antigen (SEA)-specific antibodies in serum samples from the patient group. Our study is the first regarding Tfh cells in chronic human schistosomiasis and the finding indicate that PD-1high CXCR5+ CD4+Tfh cells might play an important role in the production of specific antibodies in schistosomiasis. This study contributes to the understanding of immune response to schistosomiasis and may provide helpful support in vaccine development. PMID:26221072

Higher Frequency of Circulating PD-1(high) CXCR5(+)CD4(+) Tfh Cells in Patients with Chronic Schistosomiasis.

PubMed

Zhang, Yumei; Jiang, Yanyan; Wang, Yanjuan; Liu, Hua; Shen, Yujuan; Yuan, Zhongying; Hu, Yuan; Xu, Yuxin; Cao, Jianping

2015-01-01

The current knowledge of immunological responses to schistosomiasis is insufficient for the development of vaccine and therapies. The role of T follicular helper (Tfh) cells in schistosome infections is not fully defined. The frequency of circulating Tfh cells and serum cytokine levels were analyzed in 11 patients with chronic schistosomiasis and 10 healthy controls (HC), who reside in an endemic area for Schistosomiasis japonicum. Significantly higher frequencies of circulating CXCR5(+) CD4(+) Tfh cells and higher expression levels of ICOS and PD-1 in CXCR5(+) CD4(+) Tfh cells were observed in patients with chronic schistosomiasis compared to HC. The levels of IL-21 in serum and the expression of IL-21 mRNA were higher in chronic schistosomiasis patients than in HC. Moreover, the frequency of circulating PD-1(high) CXCR5(+) CD4(+) Tfh cells positively correlated with the levels of IL-21 in serum from patients with chronic schistosomiasis. A positive correlation was also found between the frequency of PD-1(high) CXCR5(+) CD4(+) Tfh cells and the levels of soluble egg antigen (SEA)-specific antibodies in serum samples from the patient group. Our study is the first regarding Tfh cells in chronic human schistosomiasis and the finding indicate that PD-1(high) CXCR5(+) CD4(+)Tfh cells might play an important role in the production of specific antibodies in schistosomiasis. This study contributes to the understanding of immune response to schistosomiasis and may provide helpful support in vaccine development.

[Mechanisms of immune deposit formation in glomerulonephritis].

PubMed

Bussolati, B; Camussi, G

1996-03-01

Recent experimental studies allowed the identification of several mechanisms of immune deposit formation, which are able to reproduce the morphological and clinical pattern of human glomerulonephritis. Moreover, it was shown that most of the lesions considered, in the past, as due to circulating immune complexes (IC), are instead caused by the "in situ" formation of IC. As a result of these studies, the following schematic classification was proposed: 1) immune deposits formed by glomerular localization of IC primarily formed in the circulation; 2) immune deposits formed "in situ" by reaction of circulating antibodies with fixed structural antigens; 3) immune deposits formed "in situ" by antibodies reactive with movable structural antigens; 4) immune deposits formed "in situ" by antibodies reactive with sequestered antigens leaking out of tissues; 5) IC formed "in situ" by antibodies reactive with exogenous or non-glomerular endogenous antigens planted in the glomeruli; 6) ANCA-associated glomerular disease.

Gene constellation of influenza A virus reassortants with high growth phenotype prepared as seed candidates for vaccine production.

PubMed

Fulvini, Andrew A; Ramanunninair, Manojkumar; Le, Jianhua; Pokorny, Barbara A; Arroyo, Jennifer Minieri; Silverman, Jeanmarie; Devis, Rene; Bucher, Doris

2011-01-01

Influenza A virus vaccines undergo yearly reformulations due to the antigenic variability of the virus caused by antigenic drift and shift. It is critical to the vaccine manufacturing process to obtain influenza A seed virus that is antigenically identical to circulating wild type (wt) virus and grows to high titers in embryonated chicken eggs. Inactivated influenza A seasonal vaccines are generated by classical reassortment. The classical method takes advantage of the ability of the influenza virus to reassort based on the segmented nature of its genome. In ovo co-inoculation of a high growth or yield (hy) donor virus and a low yield wt virus with antibody selection against the donor surface antigens results in progeny viruses that grow to high titers in ovo with wt origin hemagglutinin (HA) and neuraminidase (NA) glycoproteins. In this report we determined the parental origin of the remaining six genes encoding the internal proteins that contribute to the hy phenotype in ovo. The genetic analysis was conducted using reverse transcription-polymerase chain reaction (RT-PCR) and restriction fragment length polymorphism (RFLP). The characterization was conducted to determine the parental origin of the gene segments (hy donor virus or wt virus), gene segment ratios and constellations. Fold increase in growth of reassortant viruses compared to respective parent wt viruses was determined by hemagglutination assay titers. In this study fifty-seven influenza A vaccine candidate reassortants were analyzed for the presence or absence of correlations between specific gene segment ratios, gene constellations and hy reassortant phenotype. We found two gene ratios, 6:2 and 5:3, to be the most prevalent among the hy reassortants analyzed, although other gene ratios also conferred hy in certain reassortants.

Gene Constellation of Influenza A Virus Reassortants with High Growth Phenotype Prepared as Seed Candidates for Vaccine Production

PubMed Central

Fulvini, Andrew A.; Ramanunninair, Manojkumar; Le, Jianhua; Pokorny, Barbara A.; Arroyo, Jennifer Minieri; Silverman, Jeanmarie; Devis, Rene; Bucher, Doris

2011-01-01

Background Influenza A virus vaccines undergo yearly reformulations due to the antigenic variability of the virus caused by antigenic drift and shift. It is critical to the vaccine manufacturing process to obtain influenza A seed virus that is antigenically identical to circulating wild type (wt) virus and grows to high titers in embryonated chicken eggs. Inactivated influenza A seasonal vaccines are generated by classical reassortment. The classical method takes advantage of the ability of the influenza virus to reassort based on the segmented nature of its genome. In ovo co-inoculation of a high growth or yield (hy) donor virus and a low yield wt virus with antibody selection against the donor surface antigens results in progeny viruses that grow to high titers in ovo with wt origin hemagglutinin (HA) and neuraminidase (NA) glycoproteins. In this report we determined the parental origin of the remaining six genes encoding the internal proteins that contribute to the hy phenotype in ovo. Methodology The genetic analysis was conducted using reverse transcription-polymerase chain reaction (RT-PCR) and restriction fragment length polymorphism (RFLP). The characterization was conducted to determine the parental origin of the gene segments (hy donor virus or wt virus), gene segment ratios and constellations. Fold increase in growth of reassortant viruses compared to respective parent wt viruses was determined by hemagglutination assay titers. Significance In this study fifty-seven influenza A vaccine candidate reassortants were analyzed for the presence or absence of correlations between specific gene segment ratios, gene constellations and hy reassortant phenotype. We found two gene ratios, 6∶2 and 5∶3, to be the most prevalent among the hy reassortants analyzed, although other gene ratios also conferred hy in certain reassortants. PMID:21695145

Countrywide Reassessment of Schistosoma mansoni Infection in Burundi Using a Urine-Circulating Cathodic Antigen Rapid Test: Informing the National Control Program

PubMed Central

Ortu, Giuseppina; Ndayishimiye, Onésime; Clements, Michelle; Kayugi, Donatien; Campbell, Carl H.; Lamine, Mariama Sani; Zivieri, Antonio; Magalhaes, Ricardo Soares; Binder, Sue; King, Charles H.; Fenwick, Alan; Colley, Daniel G.; Jourdan, Peter Mark

2017-01-01

Following implementation of the national control program, a reassessment of Schistosoma mansoni prevalence was conducted in Burundi to determine the feasibility of moving toward elimination. A countrywide cluster-randomized cross-sectional study was performed in May 2014. At least 25 schools were sampled from each of five eco-epidemiological risk zones for schistosomiasis. Fifty randomly selected children 13–14 years of age per school were included for a single urine-circulating cathodic antigen (CCA) rapid test and, in a subset of schools, for duplicate Kato-Katz slide preparation from a single stool sample. A total of 17,331 children from 347 schools were tested using CCA. The overall prevalence of S. mansoni infection, when CCA trace results were considered negative, was 13.5% (zone range [zr] = 4.6–17.8%), and when CCA trace results were considered positive, it was 42.8% (zr = 34.3–49.9%). In 170 schools, prevalence of this infection determined using Kato-Katz method was 1.5% (zr ==0–2.7%). The overall mean intensity of S. mansoni infection determined using Kato-Katz was 0.85 eggs per gram (standard deviation = 10.86). A majority of schools (84%) were classified as non-endemic (prevalence = 0) using Kato-Katz; however, a similar proportion of schools were classified as endemic when CCA trace results were considered negative (85%) and nearly all (98%) were endemic when CCA trace results were considered positive. The findings of this nationwide reassessment using a CCA rapid test indicate that Schistosoma infection is still widespread in Burundi, although its average intensity is probably low. Further evidence is now needed to determine the association between CCA rapid test positivity and low-intensity disease transmission. PMID:28115675

Sensitivity and specificity of the circulating cathodic antigen rapid urine test in the diagnosis of Schistosomiasis mansoni infection and evaluation of morbidity in a low- endemic area in Brazil.

PubMed

Ferreira, Fernanda Teixeira; Fidelis, Thiago André; Pereira, Thiago Almeida; Otoni, Alba; Queiroz, Leonardo Campos; Amâncio, Frederico Figueiredo; Antunes, Carlos Maurício; Lambertucci, José Roberto

2017-01-01

The Kato-Katz technique is the standard diagnostic test for Schistosoma mansoni infection in rural areas. However, the utility of this method is severely limited by the day-to-day variability in host egg excretion in the stool. In high-transmission areas, the point-of-care circulating cathodic antigen (POC-CCA) urine assay has proven to be a reliable test. However, investigations of the reliability of the POC-CCA assay in low-transmission regions are under way. This study aimed to evaluate the sensitivity and specificity of the POC-CCA assay and the morbidity of schistosomiasis in a low-endemic area in Brazil. Pains City is a low-transmission zone for schistosomiasis. A total of 300 subjects aged 7-76 years were randomly selected for the POC-CCA cassette test. For S. mansoni diagnosis, three stool samples on six slides were compared with one urine sample for each subject. The sensitivity and specificity in the absence of a gold standard were calculated using latent class analysis. Clinical examinations and abdominal ultrasounds were performed in 181 volunteers to evaluate morbidity associated with schistosomiasis. The sensitivity and specificity of the Kato-Katz technique were 25.6% and 94.6%, respectively. By contrast, the sensitivity and specificity of the POC-CCA assay were 68.1% and 72.8%, respectively. Hepatosplenic schistosomiasis was diagnosed in two patients (1.1%). Overall, the POC-CCA urine assay proved to be a useful test for diagnosing S. mansoni in a low-endemic area in Brazil. Severe clinical forms of schistosomiasis can be present even in such low-endemic areas.

Validation of a urine circulating cathodic antigen cassette test for detection of Schistosoma haematobiumin uMkhanyakude district of South Africa.

PubMed

Rubaba, O; Chimbari, M J; Soko, W; Manyangadze, T; Mukaratirwa, S

2018-06-01

Circulating cathodic antigen (CCA) tests for schistosomiasis are fast and less complicated allowing making them good candidates for routine qualitative screening for schistosomiasis at point of care. The urine-CCA has been evaluated for detection of S. mansoni with promising results. Its specificity and consistency in detecting S. haematobium infection in different endemic regions has been variable. This study validated a rapid urine-CCA cassette test for qualitative detection of S. haematobium infection in an S. haematobium endemic area with low S. mansoni prevalence. Microscopic examination for the standard urine filtration technique was used to validate the commercially available urine-CCA cassette test (rapid medical diagnostics ® ). The validation was done in a sample of primary school pupils (n = 420) aged 10-15 years in schools in the Jozini Municipality, KZN. There was a relationship between infection intensity and a positive urine-CCA test. Using the urine filtration method as the gold standard, the prevalence for S. haematobium was 40%, the accuracy of the CCA kit was 54.8%, sensitivity was 68.1% while the specificity was 45.8%. The positive predictive value was 45.82% while the negative predictive value was 68.05%. Both the urine filtration and the urine-CCA methods detected heavy (≥50 eggs/10 mL urine) and light infections at statistically significant levels. The overall accuracy, sensitivity and specificity of the urine-CCA cassette test were low. The urine-CCA cassette test performed much better for heavy infections than low infections (p < 0.05) implying that the kit may not be suitable for low endemic areas. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of Channel Catfish Ictalurus Punctatus Egg Mass Loading Rate on Performance of the “See-Saw” Incubator

USDA-ARS?s Scientific Manuscript database

The “See-Saw” is a vertical-lift incubator that increases water circulation around and through channel catfish egg masses. Baskets in the incubator move up and down on racks in conventional hatchery troughs, raising the rack in one trough while lowering the rack in the adjacent trough. Egg masses ...

Genomewide analysis of reassortment and evolution of human influenza A(H3N2) viruses circulating between 1968 and 2011.

PubMed

Westgeest, Kim B; Russell, Colin A; Lin, Xudong; Spronken, Monique I J; Bestebroer, Theo M; Bahl, Justin; van Beek, Ruud; Skepner, Eugene; Halpin, Rebecca A; de Jong, Jan C; Rimmelzwaan, Guus F; Osterhaus, Albert D M E; Smith, Derek J; Wentworth, David E; Fouchier, Ron A M; de Graaf, Miranda

2014-03-01

Influenza A(H3N2) viruses became widespread in humans during the 1968 H3N2 virus pandemic and have been a major cause of influenza epidemics ever since. These viruses evolve continuously by reassortment and genomic evolution. Antigenic drift is the cause for the need to update influenza vaccines frequently. Using two data sets that span the entire period of circulation of human influenza A(H3N2) viruses, it was shown that influenza A(H3N2) virus evolution can be mapped to 13 antigenic clusters. Here we analyzed the full genomes of 286 influenza A(H3N2) viruses from these two data sets to investigate the genomic evolution and reassortment patterns. Numerous reassortment events were found, scattered over the entire period of virus circulation, but most prominently in viruses circulating between 1991 and 1998. Some of these reassortment events persisted over time, and one of these coincided with an antigenic cluster transition. Furthermore, selection pressures and nucleotide and amino acid substitution rates of all proteins were studied, including those of the recently discovered PB1-N40, PA-X, PA-N155, and PA-N182 proteins. Rates of nucleotide and amino acid substitutions were most pronounced for the hemagglutinin, neuraminidase, and PB1-F2 proteins. Selection pressures were highest in hemagglutinin, neuraminidase, matrix 1, and nonstructural protein 1. This study of genotype in relation to antigenic phenotype throughout the period of circulation of human influenza A(H3N2) viruses leads to a better understanding of the evolution of these viruses. Each winter, influenza virus infects approximately 5 to 15% of the world's population, resulting in significant morbidity and mortality. Influenza A(H3N2) viruses evolve continuously by reassortment and genomic evolution. This leads to changes in antigenic recognition (antigenic drift) which make it necessary to update vaccines against influenza A(H3N2) viruses frequently. In this study, the relationship of genetic evolution to antigenic change spanning the entire period of A(H3N2) virus circulation was studied for the first time. The results presented in this study contribute to a better understanding of genetic evolution in correlation with antigenic evolution of influenza A(H3N2) viruses.

Cross-Reactivity between Schistosoma mansoni Antigens and the Latex Allergen Hev b 7: Putative Implication of Cross-Reactive Carbohydrate Determinants (CCDs)

PubMed Central

Doenhoff, Michael J.; El-Faham, Marwa; Liddell, Susan; Fuller, Heidi R.; Stanley, Ronald G.; Schramm, Gabriele; Igetei, Joseph E.

2016-01-01

IgG antibodies produced by rabbits immunized against S. mansoni antigens cross-reacted with aqueous soluble constituents of a variety of allergens. The antibody cross-reactivity was largely sensitive to degradation by treatment of the target antigens with sodium meta-periodate, suggesting the cross-reactivity was due to carbohydrate determinants that were common to both the schistosome and the allergens (CCDs). The reaction between the rabbit antibodies and a 43 kDa molecule in a rubber latex extract was analysed further: tandem mass spectrometry identified the latex molecule as allergen Hev b 7. Rabbit anti-schistosome IgG antibodies purified by acid-elution from solid-phase latex Hev b 7 reacted with the S. mansoni egg antigens IPSE/alpha-1 and kappa-5 and cercarial antigens SPO-1 and a fatty acid-binding protein. Moreover, purified anti-S. mansoni egg, latex cross-reactive antibodies reacted with antigenic constituents of some fruits, a result of potential relevance to the latex-fruit syndrome of allergic reactions. We propose that IgG anti-schistosome antibodies that cross-react with allergens may be able to block IgE-induced allergic reactions and thus provide a possible explanation for the hygiene hypothesis. PMID:27467385

Schistosoma mansoni Phosphoenolpyruvate Carboxykinase, a Novel Egg Antigen: Immunological Properties of the Recombinant Protein and Identification of a T-Cell Epitope

PubMed Central

Asahi, Hiroko; Osman, Ahmed; Cook, Rosemary M.; LoVerde, Philip T.; Stadecker, Miguel J.

2000-01-01

In schistosomiasis mansoni, hepatic granulomatous inflammation surrounding parasite eggs is mediated by CD4+ T helper (Th) cells sensitized to schistosomal egg antigens (SEA). We previously showed that a prominent lymphoproliferative response of CD4+ Th cells from schistosome-infected C57BL/6 (BL/6) mice was directed against a 62-kDa component of SEA. A partial amino acid sequence of the 62-kDa component was found to be identical with one present in the enzyme phosphoenolpyruvate carboxykinase (PEPCK). Based on this sequence, a cDNA clone containing the entire coding region of PEPCK was identified, and the full recombinant Schistosoma mansoni PEPCK (rSm-PEPCK) of 626 amino acids was purified from a prokaryotic expression system. rSm-PEPCK strongly stimulated a specific T-cell hybridoma, 4E6, as well as CD4+ Th cells from SEA-immunized BL/6 mice and from infected BL/6, CBA, and BALB/c mice. In the infected mice, rSm-PEPCK elicited significant gamma interferon production as well as, to a lesser extent, production of interleukin-2 and -5. In BL/6 and BALB/c mice, the CD4+ Th cell response to rSm-PEPCK was greater than that directed against the egg antigen Sm-p40; conversely, CBA mice responded better to Sm-p40 than to Sm-PEPCK. A 12-amino-acid region (residues 398 to 409: DKSKDPKAHPNS) was demonstrated to contain a T-cell epitope; synthetic peptides containing this epitope significantly stimulated specific hybridoma 4E6 and polyclonal CD4+ Th cells. The identification and characterization of immunogenic egg components will contribute to the understanding and possible control of T-cell-mediated schistosomal disease. PMID:10816489

Using immunoglobulin Y as an alternative antibody for the detection of hepatitis A virus in frozen liver sections.

PubMed

Bentes, Gentil Arthur; Lanzarini, Natália Maria; Lima, Lyana Rodrigues Pinto; Manso, Pedro Paulo de Abreu; da Silva, Alexandre Dos Santos; Mouta Junior, Sergio da Silva E; Guimarães, Juliana Rodrigues; de Moraes, Marcia Terezinha Baroni; Pelajo-Machado, Marcelo; Pinto, Marcelo Alves

2015-06-01

An increasing amount of research has been conducted on immunoglobulin Y (IgY) because the use of IgY offers several advantages with respect to diagnostic testing, including its easy accessibility, low cost and translatability to large-scale production, in addition to the fact that it can be ethically produced. In a previous work, immunoglobulin was produced and purified from egg yolks (IgY) reactive to hepatitis A virus (HAV) antigens. In the present work, this anti-HAV-specific IgY was used in an indirect immunofluorescence assay to detect viral antigens in liver biopsies that were obtained from experimentally infected cynomolgus monkeys. Fields that were positive for HAV antigen were detected in liver sections using confocal microscopy. In conclusion, egg yolks from immunised hens may be a reliable source for antibody production, which can be employed for immunological studies.

Progressive antigenic drift and phylogeny of human influenza A(H3N2) virus over five consecutive seasons (2009-2013) in Hangzhou, China.

PubMed

Shao, Tie-Juan; Li, Jun; Yu, Xin-Fen; Kou, Yu; Zhou, Yin-Yan; Qian, Xin

2014-12-01

Vaccine efficacy (VE) can be affected by progressive antigenic drift or any new reassortment of influenza viruses. To effectively track the evolution of human influenza A(H3N2) virus circulating in Hangzhou, China, a total of 65 clinical specimens were selected randomly from outpatients infected by A(H3N2) viruses during the study period from November 2009 to December 2013. The results of reduced VE and antigenic drift of the correspondent epitopes (C-D-E to A-B) suggest that the current vaccine provides suboptimal protection against the A(H3N2) strains circulating recently. Phylogenetic analysis of the entire HA and NA sequences demonstrated that these two genes underwent independent evolutionary pathways during recent seasons. The H3-based phylogenetic tree showed that a special strain A/Hangzhou/A289/2012 fell in a cluster among viruses with reduced VE predominantly circulating in 2013. Our findings underscore a possible early warning for the circulation of A(H3N2) variants with antigenic drift during the previous seasons. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Respiratory allergen from house dust mite is present in human milk and primes for allergic sensitization in a mouse model of asthma.

PubMed

Macchiaverni, P; Rekima, A; Turfkruyer, M; Mascarell, L; Airouche, S; Moingeon, P; Adel-Patient, K; Condino-Neto, A; Annesi-Maesano, I; Prescott, S L; Tulic, M K; Verhasselt, V

2014-03-01

There is an urgent need to identify environmental risk and protective factors in early life for the prevention of allergy. Our study demonstrates the presence of respiratory allergen from house dust mite, Der p 1, in human breast milk. Der p 1 in milk is immunoreactive, present in similar amounts as dietary egg antigen, and can be found in breast milk from diverse regions of the world. In a mouse model of asthma, oral exposure to Der p through breast milk strongly promotes sensitization rather than protect the progeny as we reported with egg antigen. These data highlight that antigen administration to the neonate through the oral route may contribute to child allergic sensitization and have important implications for the design of studies assessing early oral antigen exposure for allergic disease prevention. The up-to-now unknown worldwide presence of respiratory allergen in maternal milk allows new interpretation and design of environmental control epidemiological studies for allergic disease prevention. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Comparative efficacy of antigen and antibody detection tests for human trichinellosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivanoska, D.; Cuperlovic, K.; Gamble, H.R.

1989-02-01

Sera collected from patients with suspected or confirmed exposure to Trichinella spiralis were tested for circulating parasite antigens and antiparasite antibodies. Using an immunoradiometric assay, excretory--secretory antigens from muscle-stage larvae of T. spiralis were detected in the sera of 47% of 62 patients with clinical trichinellosis and 13% of 39 patients without clinical signs but suspected of exposure to infected meat. In comparison, antibodies were detected using an indirect immunofluorescent test in the circulation of 100% of the 62 patients with clinical trichinellosis and 46% of the 39 patients with suspected exposure. The presence of antibodies specific to excretory-secretory productsmore » of T. spiralis muscle larvae was confirmed in the majority of the samples tested by a monoclonal antibody-based competitive inhibition assay. These results indicate that antibody detection is a more sensitive diagnostic method for human trichinellosis, but that antigen detection might be a useful confirmatory test because it is a direct demonstration of parasite products in the circulation.« less

The hamster (Mesocricetus auratus) as an experimental model of toxocariasis: histopathological, immunohistochemical, and immunoelectron microscopic findings.

PubMed

da Silva, Ana Maria Gonçalves; Chieffi, Pedro Paulo; da Silva, Wellington Luiz Ferreira; Kanashiro, Edite Hatsumi Yamashiro; Rubinsky-Elefant, Guita; Cunha-Neto, Edécio; Mairena, Eliane Conti; De Brito, Thales

2015-03-01

Toxocariasis is a globally distributed parasitic infection caused by the larval stage of Toxocara spp. The typical natural hosts of the parasite are dogs and cats, but humans can be infected by the larval stage of the parasite after ingesting embryonated eggs in soil or from contaminated hands or fomites. The migrating larvae are not adapted to complete their life cycle within accidental or paratenic hosts like humans and laboratory animals, respectively, but they are capable of invading viscera or other tissues where they may survive and induce disease. In order to characterize hamsters (Mesocricetus auratus) as a model for Toxocara canis infection, histopathological and immunohistochemistry procedures were used to detect pathological lesions and the distribution of toxocaral antigens in the liver, lungs, and kidneys of experimentally infected animals. We also attempted to characterize the immunological parameters of the inflammatory response and correlate them with the histopathological findings. In the kidney, a correlation between glomerular changes and antigen deposits was evaluated using immunoelectron microscopy. The hamster is an adequate model of experimental toxocariasis for short-term investigations and has a good immunological and pathological response to the infection. Lung and liver manifestations of toxocariasis in hamsters approximated those in humans and other experimental animal models. A mixed Th2 immunological response to T. canis infection was predominant. The hamster model displayed a progressive rise of anti-toxocaral antibodies with the formation of immune complexes. Circulating antigens, immunoglobulin, and complement deposits were detected in the kidney without the development of a definite immune complex nephropathy.

A novel dendritic cell-based direct ex vivo assay for detection and enumeration of circulating antigen-specific human T cells.

PubMed

Carrio, Roberto; Zhang, Ge; Drake, Donald R; Schanen, Brian C

2018-05-07

Although a variety of assays have been used to examine T cell responses in vitro, standardized ex vivo detection of antigen-specific CD4 + T cells from human circulatory PBMCs remains constrained by low-dimensional characterization outputs and the need for polyclonal, mitogen-induced expansion methods to generate detectable response signals. To overcome these limitations, we developed a novel methodology utilizing antigen-pulsed autologous human dendritic target cells in a rapid and sensitive assay to accurately enumerate antigen-specific CD4 + T cell precursor frequency by multiparametric flow cytometry. With this approach, we demonstrate the ability to reproducibly quantitate poly-functional T cell responses following both primary and recall antigenic stimulation. Furthermore, this approach enables more comprehensive phenotypic profiling of circulating antigen-specific CD4 + T cells, providing valuable insights into the pre-existing polarization of antigen-specific T cells in humans. Combined, this approach permits sensitive and detailed ex vivo detection of antigen-specific CD4 + T cells delivering an important tool for advancing vaccine, immune-oncology and other therapeutic studies.

21 CFR 866.6020 - Immunomagnetic circulating cancer cell selection and enumeration system.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Immunomagnetic circulating cancer cell selection... Associated Antigen immunological Test Systems § 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system. (a) Identification. An immunomagnetic circulating cancer cell selection and enumeration...

21 CFR 866.6020 - Immunomagnetic circulating cancer cell selection and enumeration system.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Immunomagnetic circulating cancer cell selection... Associated Antigen immunological Test Systems § 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system. (a) Identification. An immunomagnetic circulating cancer cell selection and enumeration...

21 CFR 866.6020 - Immunomagnetic circulating cancer cell selection and enumeration system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Immunomagnetic circulating cancer cell selection... Associated Antigen immunological Test Systems § 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system. (a) Identification. An immunomagnetic circulating cancer cell selection and enumeration...

21 CFR 866.6020 - Immunomagnetic circulating cancer cell selection and enumeration system.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Immunomagnetic circulating cancer cell selection... Associated Antigen immunological Test Systems § 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system. (a) Identification. An immunomagnetic circulating cancer cell selection and enumeration...

21 CFR 866.6020 - Immunomagnetic circulating cancer cell selection and enumeration system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Immunomagnetic circulating cancer cell selection... Associated Antigen immunological Test Systems § 866.6020 Immunomagnetic circulating cancer cell selection and enumeration system. (a) Identification. An immunomagnetic circulating cancer cell selection and enumeration...

Production of human monoclonal antibody in eggs of chimeric chickens.

PubMed

Zhu, Lei; van de Lavoir, Marie-Cecile; Albanese, Jenny; Beenhouwer, David O; Cardarelli, Pina M; Cuison, Severino; Deng, David F; Deshpande, Shrikant; Diamond, Jennifer H; Green, Lynae; Halk, Edward L; Heyer, Babette S; Kay, Robert M; Kerchner, Allyn; Leighton, Philip A; Mather, Christine M; Morrison, Sherie L; Nikolov, Zivko L; Passmore, David B; Pradas-Monne, Alicia; Preston, Benjamin T; Rangan, Vangipuram S; Shi, Mingxia; Srinivasan, Mohan; White, Steven G; Winters-Digiacinto, Peggy; Wong, Susan; Zhou, Wen; Etches, Robert J

2005-09-01

The tubular gland of the chicken oviduct is an attractive system for protein expression as large quantities of proteins are deposited in the egg, the production of eggs is easily scalable and good manufacturing practices for therapeutics from eggs have been established. Here we examined the ability of upstream and downstream DNA sequences of ovalbumin, a protein produced exclusively in very high quantities in chicken egg white, to drive tissue-specific expression of human mAb in chicken eggs. To accommodate these large regulatory regions, we established and transfected lines of chicken embryonic stem (cES) cells and formed chimeras that express mAb from cES cell-derived tubular gland cells. Eggs from high-grade chimeras contained up to 3 mg of mAb that possesses enhanced antibody-dependent cellular cytotoxicity (ADCC), nonantigenic glycosylation, acceptable half-life, excellent antigen recognition and good rates of internalization.

Detection of egg drop syndrome virus antigen or genome by enzyme-linked immunosorbent assay or polymerase chain reaction.

PubMed

Dhinakar Raj, G; Sivakumar, S; Matheswaran, K; Chandrasekhar, M; Thiagarajan, V; Nachimuthu, K

2003-10-01

Mouse monoclonal antibodies (mAbs) were produced against an Indian isolate of egg drop syndrome (EDS) virus and characterized. Four hybridoma clones were secreting mAbs that bound to a 100 kDa protein, presumably the hexon protein. These mAbs were found to cross-react with two other Indian isolates of EDS virus and to the reference UK 127 strain. Three of these mAbs were mapped to the same epitope compared with the other mAb (F8), which bound to a different epitope. An antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) was developed using the F8 mAbs as capture antibody and polyclonal chicken serum against EDS virus as detection antibody. A polymerase chain reaction (PCR) was used to detect the EDS viral genome. Following experimental infection of oestrogen-treated chickens with EDS virus, cloacal swabs, oviduct, uterus and spleen were collected at different days post-infection and used in both AC-ELISA and PCR, directly and after a single passage in embryonated duck eggs. The sensitivity and specificity of antigen detection by AC-ELISA or PCR was 95% and 98%, respectively. For diagnosis of EDS viral infections, PCR is recommended due to its ease and the lack of requirement of prepared reagents such as mAbs or conjugates. We recommend that PCR be performed directly on boiled tissue homogenates. Any negative samples may be passaged in embryonated duck eggs and the allantoic fluids tested by PCR before a conclusive negative diagnosis is given.

The global antigenic diversity of swine influenza A viruses

PubMed Central

Lewis, Nicola S; Russell, Colin A; Langat, Pinky; Anderson, Tavis K; Berger, Kathryn; Bielejec, Filip; Burke, David F; Dudas, Gytis; Fonville, Judith M; Fouchier, Ron AM; Kellam, Paul; Koel, Bjorn F; Lemey, Philippe; Nguyen, Tung; Nuansrichy, Bundit; Peiris, JS Malik; Saito, Takehiko; Simon, Gaelle; Skepner, Eugene; Takemae, Nobuhiro; Webby, Richard J; Van Reeth, Kristien; Brookes, Sharon M; Larsen, Lars; Watson, Simon J; Brown, Ian H; Vincent, Amy L

2016-01-01

Swine influenza presents a substantial disease burden for pig populations worldwide and poses a potential pandemic threat to humans. There is considerable diversity in both H1 and H3 influenza viruses circulating in swine due to the frequent introductions of viruses from humans and birds coupled with geographic segregation of global swine populations. Much of this diversity is characterized genetically but the antigenic diversity of these viruses is poorly understood. Critically, the antigenic diversity shapes the risk profile of swine influenza viruses in terms of their epizootic and pandemic potential. Here, using the most comprehensive set of swine influenza virus antigenic data compiled to date, we quantify the antigenic diversity of swine influenza viruses on a multi-continental scale. The substantial antigenic diversity of recently circulating viruses in different parts of the world adds complexity to the risk profiles for the movement of swine and the potential for swine-derived infections in humans. DOI: http://dx.doi.org/10.7554/eLife.12217.001 PMID:27113719

[Roles of sialic acids in sperm maturation and capacitation and sperm-egg recognition].

PubMed

Feng, Ying; Wang, Lin; Wu, Yi-Lun; Liu, Hong-Hua; Ma, Fang

2016-10-01

Sialic acids are a subset of nine-carbon alpha-keto aldonic acids involved in various biological functions. Sialic acid on the sperm surface is closely related to sperm maturation and capacitation and sperm-egg recognition, which makes sperm negatively charged to avoid accumulation and covers some antigenic determinants there to increase the survival rate of sperm in the female reproductive tract. The loss of sialic acids is an important factor mediating sperm capacitation. Moreover, the sialic acid at the extremity of the protein polymer is involved in signal identification in sperm-egg recognition. Here, we review the current understanding of sialic acids in sperm maturation and capacitation and sperm-egg recognition.

Antigenic Drift in H5N1 Avian Influenza Virus in Poultry Is Driven by Mutations in Major Antigenic Sites of the Hemagglutinin Molecule Analogous to Those for Human Influenza Virus▿†

PubMed Central

Cattoli, Giovanni; Milani, Adelaide; Temperton, Nigel; Zecchin, Bianca; Buratin, Alessandra; Molesti, Eleonora; Aly, Mona Meherez; Arafa, Abdel; Capua, Ilaria

2011-01-01

H5N1 highly pathogenic avian influenza virus has been endemic in poultry in Egypt since 2008, notwithstanding the implementation of mass vaccination and culling of infected birds. Extensive circulation of the virus has resulted in a progressive genetic evolution and an antigenic drift. In poultry, the occurrence of antigenic drift in avian influenza viruses is less well documented and the mechanisms remain to be clarified. To test the hypothesis that H5N1 antigenic drift is driven by mechanisms similar to type A influenza viruses in humans, we generated reassortant viruses, by reverse genetics, that harbored molecular changes identified in genetically divergent viruses circulating in the vaccinated population. Parental and reassortant phenotype viruses were antigenically analyzed by hemagglutination inhibition (HI) test and microneutralization (MN) assay. The results of the study indicate that the antigenic drift of H5N1 in poultry is driven by multiple mutations primarily occurring in major antigenic sites at the receptor binding subdomain, similarly to what has been described for human influenza H1 and H3 subtype viruses. PMID:21734057

Vaccines

MedlinePlus Videos and Cool Tools

Vaccinations are injections of antigens into the body. Once the antigens enter the blood, they circulate along with other ... B and T cells. B and T cells are white blood cells that help the body defend ...

Antigenic Characterization of H3N2 Influenza A Viruses from Ohio Agricultural Fairs

PubMed Central

Feng, Zhixin; Gomez, Janet; Bowman, Andrew S.; Ye, Jianqiang; Long, Li-Ping; Nelson, Sarah W.; Yang, Jialiang; Martin, Brigitte; Jia, Kun; Nolting, Jacqueline M.; Cunningham, Fred; Cardona, Carol; Zhang, Jianqiang; Yoon, Kyoung-Jin; Slemons, Richard D.

2013-01-01

The demonstrated link between the emergence of H3N2 variant (H3N2v) influenza A viruses (IAVs) and swine exposure at agricultural fairs has raised concerns about the human health risk posed by IAV-infected swine. Understanding the antigenic profiles of IAVs circulating in pigs at agricultural fairs is critical to developing effective prevention and control strategies. Here, 68 H3N2 IAV isolates recovered from pigs at Ohio fairs (2009 to 2011) were antigenically characterized. These isolates were compared with other H3 IAVs recovered from commercial swine, wild birds, and canines, along with human seasonal and variant H3N2 IAVs. Antigenic cartography demonstrated that H3N2 IAV isolates from Ohio fairs could be divided into two antigenic groups: (i) the 2009 fair isolates and (ii) the 2010 and 2011 fair isolates. These same two antigenic clusters have also been observed in commercial swine populations in recent years. Human H3N2v isolates from 2010 and 2011 are antigenically clustered with swine-origin IAVs from the same time period. The isolates recovered from pigs at fairs did not cross-react with ferret antisera produced against the human seasonal H3N2 IAVs circulating during the past decade, raising the question of the degree of immunity that the human population has to swine-origin H3N2 IAVs. Our results demonstrate that H3N2 IAVs infecting pigs at fairs and H3N2v isolates were antigenically similar to the IAVs circulating in commercial swine, demonstrating that exhibition swine can function as a bridge between commercial swine and the human population. PMID:23637412

An Ex Vivo Model for Studying Hepatic Schistosomiasis and the Effect of Released Protein from Dying Eggs

PubMed Central

Gobert, Geoffrey N.; Nawaratna, Sujeevi K.; Harvie, Marina; Ramm, Grant A.; McManus, Donald P.

2015-01-01

Background We report the use of an ex vivo precision cut liver slice (PCLS) mouse model for studying hepatic schistosomiasis. In this system, liver tissue is unfixed, unfrozen, and alive for maintenance in culture and subsequent molecular analysis. Methods and Findings Using thick naive mouse liver tissue and sterile culture conditions, the addition of soluble egg antigen (SEA) derived from Schistosoma japonicum eggs, followed 4, 24 and 48hrs time points. Tissue was collected for transcriptional analysis and supernatants collected to quantitate liver enzymes, cytokines and chemokines. No significant hepatotoxicity was demonstrated by supernatant liver enzymes due to the presence of SEA. A proinflammatory response was observed both at the transcriptional level and at the protein level by cytokine and chemokine bead assay. Key genes observed elevated transcription in response to the addition of SEA included: IL1-α and IL1-β, IL6, all associated with inflammation. The recruitment of antigen presenting cells was reflected in increases in transcription of CD40, CCL4 and CSF1. Indications of tissue remodeling were seen in elevated gene expression of various Matrix MetalloProteinases (MMP3, 9, 10, 13) and delayed increases in TIMP1. Collagen deposition was significantly reduced in the presence of SEA as shown in COL1A1 expression by qPCR after 24hrs culture. Cytokine and chemokine analysis of the culture supernatants confirmed the elevation of proteins including IL6, CCL3, CCL4 and CXCL5. Conclusions This ex vivo model system for the synchronised delivery of parasite antigen to liver tissue provides an insight into the early phase of hepatic schistosomiasis, corresponding with the release of soluble proteins from dying schistosome eggs. PMID:25965781

Schistosome egg antigens, including the glycoprotein IPSE/alpha-1, trigger the development of regulatory B cells

PubMed Central

Veninga, Henrike; van der Vlugt, Luciën E. P. M.; Voskamp, Astrid; Boon, Louis; Westerhof, Lotte B.; Smits, Hermelijn H.

2017-01-01

Infection with the helminth Schistosoma (S.) mansoni drives the development of interleukin (IL)-10-producing regulatory B (Breg) cells in mice and man, which have the capacity to reduce experimental allergic airway inflammation and are thus of high therapeutic interest. However, both the involved antigen and cellular mechanisms that drive Breg cell development remain to be elucidated. Therefore, we investigated whether S. mansoni soluble egg antigens (SEA) directly interact with B cells to enhance their regulatory potential, or act indirectly on B cells via SEA-modulated macrophage subsets. Intraperitoneal injections of S. mansoni eggs or SEA significantly upregulated IL-10 and CD86 expression by marginal zone B cells. Both B cells as well as macrophages of the splenic marginal zone efficiently bound SEA in vivo, but macrophages were dispensable for Breg cell induction as shown by macrophage depletion with clodronate liposomes. SEA was internalized into acidic cell compartments of B cells and induced a 3-fold increase of IL-10, which was dependent on endosomal acidification and was further enhanced by CD40 ligation. IPSE/alpha-1, one of the major antigens in SEA, was also capable of inducing IL-10 in naïve B cells, which was reproduced by tobacco plant-derived recombinant IPSE. Other major schistosomal antigens, omega-1 and kappa-5, had no effect. SEA depleted of IPSE/alpha-1 was still able to induce Breg cells indicating that SEA contains more Breg cell-inducing components. Importantly, SEA- and IPSE-induced Breg cells triggered regulatory T cell development in vitro. SEA and recombinant IPSE/alpha-1 also induced IL-10 production in human CD1d+ B cells. In conclusion, the mechanism of S. mansoni-induced Breg cell development involves a direct targeting of B cells by SEA components such as the secretory glycoprotein IPSE/alpha-1. PMID:28753651

Simultaneous quantification of the viral antigens hemagglutinin and neuraminidase in influenza vaccines by LC-MSE.

PubMed

Creskey, Marybeth C; Li, Changgui; Wang, Junzhi; Girard, Michel; Lorbetskie, Barry; Gravel, Caroline; Farnsworth, Aaron; Li, Xuguang; Smith, Daryl G S; Cyr, Terry D

2012-07-06

Current methods for quality control of inactivated influenza vaccines prior to regulatory approval include determining the hemagglutinin (HA) content by single radial immunodiffusion (SRID), verifying neuraminidase (NA) enzymatic activity, and demonstrating that the levels of the contaminant protein ovalbumin are below a set threshold of 1 μg/dose. The SRID assays require the availability of strain-specific reference HA antigens and antibodies, the production of which is a potential rate-limiting step in vaccine development and release, particularly during a pandemic. Immune responses induced by neuraminidase also contribute to protection from infection; however, the amounts of NA antigen in influenza vaccines are currently not quantified or standardized. Here, we report a method for vaccine analysis that yields simultaneous quantification of HA and NA levels much more rapidly than conventional HA quantification techniques, while providing additional valuable information on the total protein content. Enzymatically digested vaccine proteins were analyzed by LC-MS(E), a mass spectrometric technology that allows absolute quantification of analytes, including the HA and NA antigens, other structural influenza proteins and chicken egg proteins associated with the manufacturing process. This method has potential application for increasing the accuracy of reference antigen standards and for validating label claims for HA content in formulated vaccines. It can also be used to monitor NA and chicken egg protein content in order to monitor manufacturing consistency. While this is a useful methodology with potential for broad application, we also discuss herein some of the inherent limitations of this approach and the care and caution that must be taken in its use as a tool for absolute protein quantification. The variations in HA, NA and chicken egg protein concentrations in the vaccines analyzed in this study are indicative of the challenges associated with the current manufacturing and quality control testing procedures. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Dietary Whole Egg Consumption Attenuates Body Weight Gain and Is More Effective than Supplemental Cholecalciferol in Maintaining Vitamin D Balance in Type 2 Diabetic Rats.

PubMed

Saande, Cassondra J; Jones, Samantha K; Hahn, Kaylee E; Reed, Carter H; Rowling, Matthew J; Schalinske, Kevin L

2017-09-01

Background: Type 2 diabetes (T2D) is characterized by vitamin D insufficiency owing to excessive urinary loss of 25-hydroxycholecalciferol [25(OH)D]. We previously reported that a diet containing dried whole egg, a rich source of vitamin D, was effective at maintaining circulating 25(OH)D concentrations in rats with T2D. Furthermore, whole egg consumption reduced body weight gain in rats with T2D. Objective: This study was conducted to compare whole egg consumption with supplemental cholecalciferol with respect to vitamin D balance, weight gain, and body composition in rats with T2D. Methods: Male Zucker diabetic fatty (ZDF) rats ( n = 24) and their lean controls ( n = 24) were obtained at 5 wk of age and randomly assigned to 3 treatment groups: a casein-based diet (CAS), a dried whole egg-based diet (WE), or a casein-based diet containing supplemental cholecalciferol (CAS+D) at the same amount of cholecalciferol provided by WE (37.6 μg/kg diet). Rats were fed their respective diets for 8 wk. Weight gain and food intake were measured daily, circulating 25(OH)D concentrations were measured by ELISA, and body composition was analyzed by dual X-ray absorptiometry. Results: Weight gain and percentage of body fat were reduced by ∼20% and 11%, respectively, in ZDF rats fed WE compared with ZDF rats fed CAS or CAS+D. ZDF rats fed CAS had 21% lower serum 25(OH)D concentrations than lean rats fed CAS. In ZDF rats, WE consumption increased serum 25(OH)D concentrations 130% compared with CAS, whereas consumption of CAS+D increased serum 25(OH)D concentrations 35% compared with CAS. Conclusions: Our data suggest that dietary consumption of whole eggs is more effective than supplemental cholecalciferol in maintaining circulating 25(OH)D concentrations in rats with T2D. Moreover, whole egg consumption attenuated weight gain and reduced percentage of body fat in ZDF rats. These data may support new dietary recommendations targeting the prevention of vitamin D insufficiency in T2D. © 2017 American Society for Nutrition.

Trimethylamine-N-oxide (TMAO) response to animal source foods varies among healthy young men and is influenced by their gut microbiota composition: A randomized controlled trial.

PubMed

Cho, Clara E; Taesuwan, Siraphat; Malysheva, Olga V; Bender, Erica; Tulchinsky, Nathan F; Yan, Jian; Sutter, Jessica L; Caudill, Marie A

2017-01-01

Trimethylamine-N-oxide (TMAO), a metabolite linked to the gut microbiota, is associated with excess risk of heart disease. We hypothesized that (i) TMAO response to animal source foods would vary among healthy men and (ii) this response would be modified by their gut microbiome. A crossover feeding trial in healthy young men (n = 40) was conducted with meals containing TMAO (fish), its dietary precursors, choline (eggs) and carnitine (beef), and a fruit control. Fish yielded higher circulating and urinary concentrations of TMAO (46-62 times; p < 0.0001), trimethylamine (8-14 times; p < 0.0001), and dimethylamine (4-6-times; P<0.0001) than eggs, beef, or the fruit control. Circulating TMAO concentrations were increased within 15 min of fish consumption, suggesting that dietary TMAO can be absorbed without processing by gut microbes. Analysis of 16S rRNA genes indicated that high-TMAO producers (≥20% increase in urinary TMAO in response to eggs and beef) had more Firmicutes than Bacteroidetes (p = 0.04) and less gut microbiota diversity (p = 0.03). Consumption of fish yielded substantially greater increases in circulating TMAO than eggs or beef. The higher Firmicutes to Bacteroidetes enrichment among men exhibiting a greater response to dietary TMAO precursor intake indicates that TMAO production is a function of individual differences in the gut microbiome. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

EFFECT OF ACUTE STRESS ON PLASMA CONCENTRATIONS OF SEX AND STRESS HORMONES IN JUVENILE ALLIGATORS LIVING IN CONTROL AND CONTAMINATED LAKES

EPA Science Inventory

Environmental contaminants can act as stressors, inducing elevated circulating concentrations of stress hormones such as corticosterone and cortisol. Development in contaminated eggs has been reported to modify circulating sex steroid hormone concentrations in alligators (Alligat...

Genomic and antigenic characterization of the newly emerging Chinese duck egg-drop syndrome flavivirus: genomic comparison with Tembusu and Sitiawan viruses.

PubMed

Liu, Peipei; Lu, Hao; Li, Shuang; Moureau, Gregory; Deng, Yong-Qiang; Wang, Yongyue; Zhang, Lijiao; Jiang, Tao; de Lamballerie, Xavier; Qin, Cheng-Feng; Gould, Ernest A; Su, Jingliang; Gao, George F

2012-10-01

Duck egg-drop syndrome virus (DEDSV) is a newly emerging pathogenic flavivirus causing avian diseases in China. The infection occurs in laying ducks characterized by a severe drop in egg production with a fatality rate of 5-15 %. The virus was found to be most closely related to Tembusu virus (TMUV), an isolate from mosquitoes in South-east Asia. Here, we have sequenced and characterized the full-length genomes of seven DEDSV strains, including the 5'- and 3'-non-coding regions (NCRs). We also report for the first time the ORF sequences of TMUV and Sitiawan virus (STWV), another closely related flavivirus isolated from diseased chickens. We analysed the phylogenetic and antigenic relationships of DEDSV in relation to the Asian viruses TMUV and STWV, and other representative flaviviruses. Our results confirm the close relationship between DEDSV and TMUV/STWV and we discuss their probable evolutionary origins. We have also characterized the cleavage sites, potential glycosylation sites and unique motifs/modules of these viruses. Additionally, conserved sequences in both 5'- and 3'-NCRs were identified and the predicted secondary structures of the terminal sequences were studied. Antigenic cross-reactivity comparisons of DEDSV with related pathogenic flaviviruses identified a surprisingly close relationship with dengue virus (DENV) and raised the question of whether or not DEDSV may have a potential infectious threat to man. Importantly, DEDSV can be efficiently recognized by a broadly cross-reactive flavivirus mAb, 2A10G6, derived against DENV. The significance of these studies is discussed in the context of the emergence, evolution, epidemiology, antigenicity and pathogenicity of the newly emergent DEDSV.

Egg buoyancy variability in local populations of Atlantic cod (Gadus morhua).

PubMed

Jung, Kyung-Mi; Folkvord, Arild; Kjesbu, Olav Sigurd; Agnalt, Ann Lisbeth; Thorsen, Anders; Sundby, Svein

2012-01-01

Previous studies have found strong evidences for Atlantic cod ( Gadus morhua ) egg retention in fjords, which are caused by the combination of vertical salinity structure, estuarine circulation, and egg specific gravity, supporting small-scaled geographical differentiations of local populations. Here, we assess the variability in egg specific gravity for selected local populations of this species, that is, two fjord-spawning populations and one coastal-spawning population from Northern Norway (66-71°N/10-25°E). Eggs were naturally spawned by raised broodstocks (March to April 2009), and egg specific gravity was measured by a density-gradient column. The phenotype of egg specific gravity was similar among the three local populations. However, the associated variability was greater at the individual level than at the population level. The noted gradual decrease in specific gravity from gastrulation to hatching with an increase just before hatching could be a generic pattern in pelagic marine fish eggs. This study provides needed input to adequately understand and model fish egg dispersal.

Duck egg drop syndrome virus: an emerging Tembusu-related flavivirus in China.

PubMed

Liu, PeiPei; Lu, Hao; Li, Shuang; Wu, Ying; Gao, George Fu; Su, JingLiang

2013-08-01

Duck egg drop syndrome virus (DEDSV) is a newly emerging pathogenic flavivirus isolated from ducks in China. DEDSV infection mainly results in severe egg drop syndrome in domestic poultry, which leads to huge economic losses. Thus, the discovery of ways and means to combat DEDSV is urgent. Since 2010, a remarkable amount of progress concerning DEDSV research has been achieved. Here, we review current knowledge on the epidemiology, symptomatology, and pathology of DEDSV. A detailed dissection of the viral genome and polyprotein sequences, comparative analysis of viral antigenicity and the corresponding potential immunity against the virus are also summarized. Current findings indicate that DEDSV should be a distinct species from Tembusu virus. Moreover, the adaption of DEDSV in wildlife and its high homology to pathogenic flaviviruses (e.g., West Nile virus, Japanese encephalitis virus, and dengue virus), illustrate its reemergence and potential to become a zoonotic pathogen that should not be overlooked. Detailed insight into the antigenicity and corresponding immunity against the virus is of clear significance for the development of vaccines and antiviral drugs specific for DEDSV.

Antigenic variation of the human influenza A (H3N2) virus during the 2014-2015 winter season.

PubMed

Hua, Sha; Li, XiYan; Liu, Mi; Cheng, YanHui; Peng, YouSong; Huang, WeiJuan; Tan, MinJu; Wei, HeJiang; Guo, JunFeng; Wang, DaYan; Wu, AiPing; Shu, YueLong; Jiang, TaiJiao

2015-09-01

The human influenza A (H3N2) virus dominated the 2014-2015 winter season in many countries and caused massive morbidity and mortality because of its antigenic variation. So far, very little is known about the antigenic patterns of the recent H3N2 virus. By systematically mapping the antigenic relationships of H3N2 strains isolated since 2010, we discovered that two groups with obvious antigenic divergence, named SW13 (A/Switzerland/9715293/2013-like strains) and HK14 (A/Hong Kong/5738/2014-like strains), co-circulated during the 2014-2015 winter season. HK14 group co-circulated with SW13 in Europe and the United States during this season, while there were few strains of HK14 in mainland China, where SW13 has dominated since 2012. Furthermore, we found that substitutions near the receptor-binding site on hemagglutinin played an important role in the antigenic variation of both the groups. These findings provide a comprehensive understanding of the recent antigenic evolution of H3N2 virus and will aid in the selection of vaccine strains.

Application of recombinant hemagglutinin proteins as alternative antigen standards for pandemic influenza vaccines.

PubMed

Choi, Yejin; Kwon, Seong Yi; Oh, Ho Jung; Shim, Sunbo; Chang, Seokkee; Chung, Hye Joo; Kim, Do Keun; Park, Younsang; Lee, Younghee

2017-09-01

The single radial immunodiffusion (SRID) assay, used to quantify hemagglutinin (HA) in influenza vaccines, requires reference reagents; however, because centralized production of reference reagents may slow the emergency deployment of vaccines, alternatives are needed. We investigated the production of HA proteins using recombinant DNA technology, rather than a traditional egg-based production process. The HA proteins were then used in an SRID assay as a reference antigen. We found that HA can be quantified in both egg-based and cell-based influenza vaccines when recombinant HAs (rHAs) are used as the reference antigen. Furthermore, we confirmed that rHAs obtained from strains with pandemic potential, such as H5N1, H7N3, H7N9, and H9N2 strains, can be utilized in the SRID assay. The rHA production process takes just one month, in contrast to the traditional process that takes three to four months. The use of rHAs may reduce the time required to produce reference reagents and facilitate timely introduction of vaccines during emergencies.

Improvement of an enzyme immunosorbent assay for detecting antibodies against Dioctophyma renale.

PubMed

Pedrassani, Daniela; do Nascimento, Adjair Antonio; André, Marcos Rogério; Machado, Rosangela Zacarias

2015-09-15

An available enzyme-linked immunosorbent assay (ELISA) was studied for the detection of anti-Dioctophyma renale antibodies in the sera of dogs using, detection of parasite eggs in urine sediment as a reference test. ELISA uses a soluble antigenic preparation of esophagus of D. renale and the optimal dilutions of the antigen, serum and conjugate were determined by means of checker board titration, using positive (n=13) and negative (n=27) reference serum. The specificity and sensitivity of the ELISA were 93.8% and 92.3% respectively and the kappa index was good (0.76). These results suggest that ELISA described may prove to be an effective serological test for detecting dogs infected and exposed to this parasite mainly dogs that are not eliminating parasite eggs through their urine. Copyright © 2015 Elsevier B.V. All rights reserved.

Basophil degranulation induced by oral poison ivy antigen.

PubMed

Shelley, W B; Resnik, S S

1965-08-01

Seven subjects shown by patch test to be sensitive to poison ivy oleoresin were challenged with graded oral doses of ivy extract. In each instance the circulating basophil leukocytes showed significant degranulation within one hour of challenge. This finding was interpreted as evidence of the presence of immediate-type circulating antibody to ivy antigen in these subjects. No drop in the absolute basophil count was noted, but with higher oral doses the degranulation persisted for several days. Thirteen control subjects showed no change in the basophil morphology or count, indicating that the resin at these levels was not toxic to this cell. All but one of the sensitive subjects showed objective patch test evidence of hyposensitization following the intensive three-week course of oral poison ivy antigen.

Identification of Low- and High-Impact Hemagglutinin Amino Acid Substitutions That Drive Antigenic Drift of Influenza A(H1N1) Viruses

PubMed Central

Harvey, William T.; Benton, Donald J.; Gregory, Victoria; Hall, James P. J.; Daniels, Rodney S.; Bedford, Trevor; Haydon, Daniel T.; Hay, Alan J.; McCauley, John W.; Reeve, Richard

2016-01-01

Determining phenotype from genetic data is a fundamental challenge. Identification of emerging antigenic variants among circulating influenza viruses is critical to the vaccine virus selection process, with vaccine effectiveness maximized when constituents are antigenically similar to circulating viruses. Hemagglutination inhibition (HI) assay data are commonly used to assess influenza antigenicity. Here, sequence and 3-D structural information of hemagglutinin (HA) glycoproteins were analyzed together with corresponding HI assay data for former seasonal influenza A(H1N1) virus isolates (1997–2009) and reference viruses. The models developed identify and quantify the impact of eighteen amino acid substitutions on the antigenicity of HA, two of which were responsible for major transitions in antigenic phenotype. We used reverse genetics to demonstrate the causal effect on antigenicity for a subset of these substitutions. Information on the impact of substitutions allowed us to predict antigenic phenotypes of emerging viruses directly from HA gene sequence data and accuracy was doubled by including all substitutions causing antigenic changes over a model incorporating only the substitutions with the largest impact. The ability to quantify the phenotypic impact of specific amino acid substitutions should help refine emerging techniques that predict the evolution of virus populations from one year to the next, leading to stronger theoretical foundations for selection of candidate vaccine viruses. These techniques have great potential to be extended to other antigenically variable pathogens. PMID:27057693

Evaluation of the CCA Immuno-Chromatographic Test to Diagnose Schistosoma mansoni in Minas Gerais State, Brazil

PubMed Central

Silveira, Alda Maria Soares; Costa, Emanuele Gama Dutra; Ray, Debalina; Suzuki, Brian M.; Hsieh, Michael H.; Fraga, Lucia Alves de Oliveira; Caffrey, Conor R.

2016-01-01

Background The Kato-Katz (KK) stool smear is the standard test for the diagnosis of Schistosoma mansoni infection, but suffers from low sensitivity when infections intensities are moderate to low. Thus, misdiagnosed individuals remain untreated and contribute to the disease transmission, thereby forestalling public health efforts to move from a modality of disease control to one of elimination. As an alternative, the urine-based diagnosis of schistosomiasis mansoni via the circulating cathodic antigen immuno-chromatographic test (CCA-ICT) has been extensively evaluated in Africa with the conclusion that it may replace the KK test in areas where prevalences are moderate or high. Methods and Findings The objective was to measure the performance of the CCA-ICT in a sample study population composed of residents from non-endemic and endemic areas for schistosomiasis mansoni in two municipalities of Minas Gerais state, Brazil. Volunteers (130) were classified into three infection status groups based on duplicate Kato-Katz thick smears from one stool sample (2KK test): 41 negative individuals from non-endemic areas, 41 negative individuals from endemic areas and 48 infected individuals from endemic areas. Infection status was also determined by the CCA-ICT and infection exposure by antibody ELISA (enzyme-linked immunosorbent assay) to S. mansoni soluble egg antigen (SEA) and soluble (adult) worm antigen preparation (SWAP). Sensitivity and specificity were influenced by whether the trace score visually adjudicated in the CCA-ICT was characterized as positive or negative for S. mansoni infection. An analysis of a two-graph receiver operating characteristic was performed to change the cutoff point. When the trace score was interpreted as a positive rather than as a negative result, the specificity decreased from 97.6% to 78.0% whereas sensitivity increased from 68.7% to 85.4%. A significantly positive correlation between the CCA-ICT scores and egg counts was identified (r = 0.6252, p = 0.0001). However, the CCA-ICT misdiagnosed as negative 14.6% of 2KK positive individuals, predominantly those with light infections (fewer than 100 eggs/g feces). Considering 2KK as reference test, the discriminating power of the CCA-ICT (the area under the curve [AUC] = 0.817) was greater than the SEA-ELISA (AUC = 0.744) and SWAP-ELISA (AUC = 0.704). Conclusion Our data for the performance of the CCA-ICT in the Brazilian communities endemic for schistosomiasis mansoni support those from Africa, i.e., in areas with greater infection prevalence and intensities, the CCA-ICT may be useful as a tool to indicate community-based preventative chemotherapy without individual diagnosis. However, because of the Brazilian Ministry of Health’s recommendation for individual diagnosis in areas where prevalence is less than 15%, i.e., those areas in which infection intensities are likely to be lowest, the CCA-ICT lacks the sensitivity to be used as standalone diagnostic tool. PMID:26752073

Antigenic profile and localization of Clonorchis sinensis proteins in the course of infection

PubMed Central

Kim, Tae Yun; Song, Kye-Yong; Sohn, Woon-Mok; Kang, Shin-Yong

2001-01-01

In the course of Clonorchis sinensis infection, antigens presented to the hosts may be in a close relation to growth of the fluke. The antigenic proteins stimulating IgG antibody production were chronologically identified by immunoblot and localized by immunohistochemical staining. In the early stage of infection until 12 weeks post-infection (PI), antigens were proteins with molecular mass larger than 34 kDa which were derived from the tegument, testes and intrauterine eggs. After 20 weeks PI, antigens recognized were 29, 27 and 26 kDa proteins from the intestine, excretory bladder and reproductive organs. It is suggested that the tegumental proteins are the most potent antigens and the excretory-secretory proteins with middle molecular mass of 26-45 kDa contribute to the high level production of antibodies after 20 weeks of the C. sinensis infection. PMID:11775331

[Epidemiologic and clinical study of paragonimosis in Cameroon. Results of niclofolan treatment].

PubMed

Ripert, C; Carrie, J; Ambroise-Thomas, P; Baecher, R; Kum, N P; Same-Ekobo, A

1981-01-01

Paragonimiasis does not occur only in the South West Province of Cameroon. Four foci exist in the country. They are the well known focus in the Mount Kupe area, the Mbam focus, the Nyong focus and the Ntem focus. All of them are located in the rainforest within the distribution area of Potadoma. This disease, characterized by the presence of eggs in sputum and feces, has often been confused with tuberculosis. In the villages where paragonimiasis is diagnosed by means of parasitological techniques circulating antibodies, revealed with a P. westermani antigen (ELISA), are often found in blood specimens taken from inhabitants. Teen agers suffer the most from the disease and females more often than males. Women and children are traditionally concerned with crabs fishing and they eat them after partly raw. Crabs of the genus Sudanautes contain the infective metacercariae. Paragonimiasis is enzootic and the civet cat V. civetta seems to be the main natural definitive host in Cameroon. Niclofolan given orally in a single dose of 2 mg/kg body weight showed a 100% cure rate. Side reactions are mild and transient.

Evolution of the hemagglutinin gene of H3N8 canine influenza virus in dogs.

PubMed

Pecoraro, Heidi L; Bennett, Susi; Spindel, Miranda E; Landolt, Gabriele A

2014-12-01

With the widespread use of a recently developed canine influenza virus (CIV) H3N8 vaccine, continual molecular evaluation of circulating CIVs is necessary for monitoring antigenic drift. The aim of this project was to further describe the genetic evolution of CIV, as well as determine any genetic variation within potential antigenic regions that might result in antigenic drift. To this end, the hemagglutinin gene of 19 CIV isolates from dogs residing in Colorado, New York, and South Carolina humane shelters was sequenced and compared to CIV strains isolated during 2003-2012. Phylogenetic analysis suggests that CIV might be diverging into two geographically distinct lineages. Using a mixed-effects model for evolution and single likelihood ancestor counting methods, several amino acid sites were found to be undergoing selection pressure. Additionally, a total of six amino acid changes were observed in two possible antigenic sites for CIVs isolated from Colorado and New York humane shelters between 2009 and 2011. As CIV isolates might be diverging into geographically distinct lineages, further experiments are warranted to determine the extent of antigenic drift occurring within circulating CIV.

Cross-reactions of sera from dogs infected with Angiostrongylus vasorum in commercially available Dirofilaria immitis test kits.

PubMed

Schnyder, Manuela; Deplazes, Peter

2012-11-13

Dirofilaria immitis and Angiostrongylus vasorum are both important potentially fatal canine nematodes with overlapping endemic areas, especially in Europe. The preadult and adult stages of both species are living in the Arteria pulmonalis and the right heart, and diagnostically detectable circulating parasite antigens have been demonstrated for both species. For the detection of D. immitis infections, a variety of commercial tests have been developed, however, they have not been evaluated for cross-reactions against circulating antigens of A. vasorum. In this study, potential cross-reactions of sera from 16 dogs, which were experimentally infected with A. vasorum and which had circulating antigens as confirmed by a species-specific ELISA, were evaluated for the detection of A. vasorum antigen in six commercially available D. immitis test kits. In three fast tests (Witness® Dirofilaria, SensPERT® Canine Heartworm, SNAP® 4Dx® Plus), all sera were negative. One fast membrane ELISA (SNAP® HTWM RT Test) was positive with four sera (25%), and one serum delivered a non-valid result twice. In the PetChek® HTWM PF Test, depending on the interpretation protocol, 5 or 8 dogs (31.2 - 50%) were positive. With the DiroCHEK®-ELISA, a single A. vasorum-infected dog (6.2%) tested positive. Due to potential cross-reactions with A. vasorum in commercially available test kits for the detection of D. immitis antigen, the simultaneous use of highly specific diagnostic methods for the differentiation of these two canine heart worms is recommended.

IgY antibodies in human nutrition for disease prevention.

PubMed

Müller, Sandra; Schubert, Andreas; Zajac, Julia; Dyck, Terry; Oelkrug, Christopher

2015-10-20

Oral administration of preformed specific antibodies is an attractive approach against infections of the digestive system in humans and animals in times of increasing antibiotic resistances. Previous studies showed a positive effect of egg yolk IgY antibodies on bacterial intoxications in animals and humans. Immunization of chickens with specific antigens offers the possibility to create various forms of antibodies. Research shows that orally applied IgY's isolated from egg yolks can passively cure or prevent diseases of the digestive system. The use of these alternative therapeutic drugs provides further advantages: (1) The production of IgY's is a non-invasive alternative to current methods; (2) The keeping of chickens is inexpensive; (3) The animals are easy to handle; (4) It avoids repetitive bleeding of laboratory animals; (5) It is also very cost effective regarding the high IgY concentration within the egg yolk. Novel targets of these antigen specific antibodies are Helicobacter pylori and also molecules involved in signaling pathways in gastric cancer. Furthermore, also dental caries causing bacteria like Streptococcus mutans or opportunistic Pseudomonas aeruginosa in cystic fibrosis patients are possible targets. Therefore, IgY's included in food for human consumption may be able to prevent or cure human diseases.

Enhancement of antibody response by one-trial conditioning: contrasting results using different antigens.

PubMed

Espinosa, Enrique; Calderas, Tania; Flores-Muciño, Oscar; Pérez-García, Georgina; Vázquez-Camacho, Ana C; Bermúdez-Rattoni, Federico

2004-01-01

New research in conditioned enhancement of antibody response requires a general paradigm effective with different antigens. In this experiment series we applied a one-trial protocol using keyhole limpet hemocyanin immunization as an unconditioned stimulus. Several different conditions were tested. Two different times between conditioning and test trial, two relevant antigen doses and the use of an antigen booster during test trial were investigated. We did not find a conditioned effect in any of the conditions used. In contrast, we found a reliable albeit modest conditioned effect using hen egg lysozyme as unconditioned stimulus. By comparing these and other findings we conclude that the number of conditioning trials is a possible requirement for a more reliable conditioning of antibody response.

No evidence for adaptation of current egg drop syndrome 1976 viruses to chickens.

PubMed

Tsukamoto, K; Kuwabara, M; Kaneko, M; Mase, M; Imai, K

2004-01-01

In order to determine whether the current field strains of egg drop syndrome (EDS) 1976 viruses adapt to chickens, we compared the growth efficiency of three Japanese field strains (PA-1/79, AWI/98, Gifu/01) in chicken and duck embryo liver cells. The growth efficiency in chicken or duck embryo liver cells was almost similar in these strains. The fiber protein may carry the type-specific antigen and the hemagglutination activity, and hexon protein may contain the subgroup-specific antigenic determinants. Therefore, the fiber head and hexon loop 1 DNA domain sequences of the six Japanese field strains UPA-1/79, ME/80, 44/81, Kyoto/91, AWI/98, Gifu/01) were compared, but these DNA domains were identical among the six field strains. Our data suggested that the EDS virus was maintained without discernible changes for the last two decades in the field.

Tissue-associated self-antigens containing exosomes: Role in allograft rejection.

PubMed

Sharma, Monal; Ravichandran, Ranjithkumar; Bansal, Sandhya; Bremner, Ross M; Smith, Michael A; Mohanakumar, T

2018-06-15

Exosomes are extracellular vesicles that express self-antigens (SAgs) and donor human leukocyte antigens. Tissue-specific exosomes can be detected in the circulation following lung, heart, kidney and islet cell transplantations. We collected serum samples from patients who had undergone lung (n = 30), heart (n = 8), or kidney (n = 15) transplantations to isolate circulating exosomes. Exosome purity was analyzed by Western blot, using CD9 exosome-specific markers. Tissue-associated lung SAgs, collagen V (Col-V) and K-alpha 1 tubulin (Kα1T), heart SAgs, myosin and vimentin, and kidney SAgs, fibronectin and collagen IV (Col-IV), were identified using western blot. Lung transplant recipients diagnosed with bronchiolitis obliterans syndrome had exosomes with higher expression of Col-V (4.2-fold) and Kα1T (37.1-fold) than stable. Exosomes isolated from heart transplant recipients diagnosed with coronary artery vasculopathy had a 3.9-fold increase in myosin and a 4.7-fold increase in vimentin compared with stable. Further, Kidney transplant recipients diagnosed with transplant glomerulopathy had circulating exosomes with a 2-fold increased expression of fibronectin and 2.5-fold increase in Col-IV compared with stable. We conclude that circulating exosomes with tissue associated SAgs have the potential to be a noninvasive biomarker for allograft rejection. Copyright © 2018. Published by Elsevier Inc.

COMPARATIVE HISTOLOGIC AND IMMUNOLOGIC STUDIES IN RABBITS OF INDUCED HYPERSENSITIVITY OF THE SERUM SICKNESS TYPE

PubMed Central

Germuth, Frederick G.; Pace, Mary Geraldine; Tippett, Jack C.

1955-01-01

Sensitization of rabbits with bovine albumin and the cross-reactive antigen, egg albumin, increased the rate of bovine albumin elimination following its intravenous administration. Elimination of this antigen was complete in 7 and 10 days respectively instead of approximately 2 weeks as in unsensitized normal animals. The peak incidence of allergic tissue alteration was proportionately accelerated. Certain qualitative and quantitative differences between the histologic responses of the sensitized and unsensitized rabbits were noted. These differences were probably due to the shorter period of antigen-antibody interaction in the sensitized animals in which the antigen was quickly eliminated. The temporal relationship between the histologic and immunologic responses in sensitized animals adds further support to the hypothesis that the lesions which occur after the injection of foreign protein are the result of antigen-antibody combination. PMID:13233442

Albumin is synthesized in epididymis and aggregates in a high molecular mass glycoprotein complex involved in sperm-egg fertilization.

PubMed

Arroteia, Kélen Fabíola; Barbieri, Mainara Ferreira; Souza, Gustavo Henrique Martins Ferreira; Tanaka, Hiromitsu; Eberlin, Marcos Nogueira; Hyslop, Stephen; Alvares, Lúcia Elvira; Pereira, Luís Antonio Violin Dias

2014-01-01

The epididymis has an important role in the maturation of sperm for fertilization, but little is known about the epididymal molecules involved in sperm modifications during this process. We have previously described the expression pattern for an antigen in epididymal epithelial cells that reacts with the monoclonal antibody (mAb) TRA 54. Immunohistochemical and immunoblotting analyses suggest that the epitope of the epididymal antigen probably involves a sugar moiety that is released into the epididymal lumen in an androgen-dependent manner and subsequently binds to luminal sperm. Using column chromatography, SDS-PAGE with in situ digestion and mass spectrometry, we have identified the protein recognized by mAb TRA 54 in mouse epididymal epithelial cells. The ∼65 kDa protein is part of a high molecular mass complex (∼260 kDa) that is also present in the sperm acrosomal vesicle and is completely released after the acrosomal reaction. The amino acid sequence of the protein corresponded to that of albumin. Immunoprecipitates with anti-albumin antibody contained the antigen recognized by mAb TRA 54, indicating that the epididymal molecule recognized by mAb TRA 54 is albumin. RT-PCR detected albumin mRNA in the epididymis and fertilization assays in vitro showed that the glycoprotein complex containing albumin was involved in the ability of sperm to recognize and penetrate the egg zona pellucida. Together, these results indicate that epididymal-derived albumin participates in the formation of a high molecular mass glycoprotein complex that has an important role in egg fertilization.

Evaluating a point-of-care circulating cathodic antigen test (POC-CCA) to detect Schistosoma mansoni infections in a low endemic area in north-eastern Brazil.

PubMed

Bezerra, Fernando Schemelzer Moraes; Leal, Joames Kauffimann Freitas; Sousa, Mariana Silva; Pinheiro, Marta Cristhiany Cunha; Ramos, Alberto Novaes; Silva-Moraes, Vanessa; Katz, Naftale

2018-06-01

Schistosomiasis is still a public health problem in Brazil. The Kato-Katz test is the most frequently used diagnostic method for Schistosoma mansoni infection. However, it lacks sensitivity in areas of low prevalence. We have assessed the positivity rate of S. mansoni infection in Bananeiras, a village on Capistrano, Ceara, Brazil by performing a point-of-care test in urine to determine the circulating cathodic antigens (POC-CCA), and we compared the findings with those of the Kato-Katz technique for egg detection in stool and an enzyme-linked immunosorbent assay for specific antibodies against adult worms (SWAP-ELISA) in serum before treatment (baseline). Additionally, the POC-CCA and Kato-Katz test results were compared at one and two years post-treatment, and only POC-CCA strips were utilised for follow-up testing on urine samples at 3-6 weeks. Only one sample of stool and urine was collected per event. Overall, 258 individuals were investigated at the baseline. The POC-CCA test detected 10 (3.9%) positive cases; however, this amount increased to 30 (11.6%) when considering trace readings as positive (t + ), whereas the Kato-Katz method found only 4 (1.6%) positive cases and the SWAP-ELISA detected 105 (40.7%) positive cases. The consistency observed between a single POC-CCA (t + ) or (t-) and the Kato-Katz (three slides) was poor (Kappa indexes <0.20). The highest positivity rate as determined by CCA and Kato-Katz was found in adults. At the baseline, a praziquantel treatment was administered to all individuals regardless of their infection status. According to the POC-CCA test, 93% of the previous positive cases became negative by the third week after the treatment; this rate reached 100% at the sixth week assessment. The follow-up showed that of the 175 individuals evaluated at one year post-treatment, only one (0.6%) showed 'trace' results, and all the individuals were negative for eggs in the stool. At two years, all 185 examined individuals were negative by the Kato-Katz method, and 11 (5.9%) presented traces by POC-CCA. Our results indicate that a single POC-CCA test reveals a significantly higher number of positive cases than the Kato-Katz technique for diagnosing S. mansoni in a low endemic setting, when trace results are considered as positive cases. Nevertheless, the true significance of the trace is not clear. These findings reinforce the need to associate different tools for improved schistosomiasis diagnosis in individuals with low parasite burdens. Copyright © 2018. Published by Elsevier B.V.

Immunology of human schistosomiasis

PubMed Central

Colley, D G; Secor, W E

2014-01-01

There is a wealth of immunologic studies that have been carried out in experimental and human schistosomiasis that can be classified into three main areas: immunopathogenesis, resistance to reinfection and diagnostics. It is clear that the bulk of, if not all, morbidity due to human schistosomiasis results from immune-response-based inflammation against eggs lodged in the body, either as regulated chronic inflammation or resulting in fibrotic lesions. However, the exact nature of these responses, the antigens to which they are mounted and the mechanisms of the critical regulatory responses are still being sorted out. It is also becoming apparent that protective immunity against schistosomula as they develop into adult worms develops slowly and is hastened by the dying of adult worms, either naturally or when they are killed by praziquantel. However, as with anti-egg responses, the responsible immune mechanisms and inducing antigens are not clearly established, nor are any potential regulatory responses known. Finally, a wide variety of immune markers, both cellular and humoral, can be used to demonstrate exposure to schistosomes, and immunologic measurement of schistosome antigens can be used to detect, and thus diagnose, active infections. All three areas contribute to the public health response to human schistosome infections. PMID:25142505

Pavlovian Conditioning of Rat Mucosal Mast Cells to Secrete Rat Mast Cell Protease II

NASA Astrophysics Data System (ADS)

MacQueen, Glenda; Marshall, Jean; Perdue, Mary; Siegel, Shepard; Bienenstock, John

1989-01-01

Antigen (egg albumin) injections, which stimulate mucosal mast cells to secrete mediators, were paired with an audiovisual cue. After reexposure to the audiovisual cue, a mediator (rat mast cell protease II) was measured with a sensitive and specific assay. Animals reexposed to only the audiovisual cue released a quantity of protease not significantly different from animals reexposed to both the cue and the antigen; these groups released significantly more protease than animals that had received the cue and antigen in a noncontingent manner. The results support a role for the central nervous system as a functional effector of mast cell function in the allergic state.

Emergence of antigenic variants within serotype A FMDV in the Middle East with antigenically critical amino acid substitutions.

PubMed

Mahapatra, Mana; Statham, Bob; Li, Yanmin; Hammond, Jef; Paton, David; Parida, Satya

2016-06-08

A new immunologically distinct strain (A-Iran-05) of foot-and-mouth disease virus serotype A emerged in the Middle East in 2003 that replaced the previously circulating strains (A-Iran-96 and A-Iran-99) in the region. This resulted in introduction of a new vaccine of this strain (A/TUR/2006) in 2006. Though this vaccine strain has been predominantly used to control FMD in the region, recent viruses isolated in 2012 and 2013 have shown antigenic drift and a poor match with it. In this study, we report the antigenic matching results and capsid sequence data of currently circulating viruses belonging to the SIS-10 and SIS-12 sub-lineages of A-Iran-05 (isolated in 2012 and 2013), highlighting the inadequacy of the currently used serotype A vaccines. Implications of these results in the context of FMD control in the Middle East are discussed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Serum IgE and IgG responses to food antigens in normal and atopic dogs, and dogs with gastrointestinal disease.

PubMed

Foster, A P; Knowles, T G; Moore, A Hotston; Cousins, P D G; Day, M J; Hall, E J

2003-05-12

In human food allergy, with or without concurrent atopy, there may be significant increases in serum allergen-specific IgE. Serological methods have been tried but are not currently recommended for diagnosis of suspected food allergy in dogs. The aim of this study was to investigate humoral immune responses to food antigens in dogs. Serum IgG and IgE antibodies specific for food antigens were measured by enzyme linked immunosorbent assay (ELISA) using polyclonal anti-dog IgG and IgE reagents. Antigens tested were beef, chicken, pork, lamb, chicken, turkey, white fish, whole egg, wheat, soybean, barley, rice, maize corn, potato, yeast and cow's milk. Three groups were examined: normal dogs, dogs with atopic dermatitis (AD); and dogs with one of four types of gastrointestinal (GI) disease: small intestinal bacterial overgrowth (SIBO), inflammatory bowel disease (IBD), food-responsive disease, and infectious diarrhoea. Statistically significant differences in food-specific antibodies were not detected between the GI subgroups. There were statistically significant differences in the IgE concentration between the normal dogs, and dogs with atopic or GI disease, for all of the antigens tested. There were statistically significant differences in the average IgG concentrations between the normal dogs, and dogs with atopic or GI disease, for all of the antigens tested, except egg and yeast. The relationship of antigen responses for pooled data was analysed using principle component analysis and cluster plots. Some clustering of variables was apparent for both IgE and IgG. For example, all dogs (normal and diseased) made a similar IgG antibody response to chicken and turkey. Compared with other groups, atopic dogs had more food allergen-specific IgE and this would be consistent with a Th(2) humoral response to food antigens. Dogs with GI disease had more food allergen-specific IgG compared with the other groups. This may reflect increased antigen exposure due to increased mucosal permeability which is a recognised feature of canine intestinal disease.

O-polysaccharide is important for Salmonella Pullorum survival in egg albumen, and virulence and colonization in chicken embryos.

PubMed

Guo, Rongxian; Li, Zhuoyang; Jiao, Yang; Geng, Shizhong; Pan, Zhiming; Chen, Xiang; Li, Qiuchun; Jiao, Xinan

2017-10-01

The pathogen Salmonella Pullorum is the causative agent of persistent systemic infection of poultry, leading to economic losses in developing countries due to morbidity, mortality and reduction in egg production. These infections may result in vertical transmission to eggs or progeny. Limited information is available regarding the mechanisms involved in the survival of Salmonella Pullorum in egg albumen and developing chicken embryos. Hence, we investigated the role of O-polysaccharide in the contamination of eggs and the colonization of chicken embryos. Compared with the wild-type strain, the isogenic waaL mutant exhibited an O-antigen-deficient rough phenotype, and increased sensitivity to egg albumen and chicken serum, as well as reduced adherence to DF-1 cells. Infection with Salmonella Pullorum lacking O-polysaccharide resulted in significantly reduced embryo lethality and bacterial colonization. These results suggest that O-polysaccharide is essential for Salmonella Pullorum colonization in eggs, both post-lay and developing embryos. The chicken embryo infection model could be used to characterize the interaction between Salmonella Pullorum and developing embryos, and it will also contribute to the development of more rational vaccines to protect laying hens and embryos.

The immunogenicity of phagocytosed T4 bacteriophage: cell replacement studies with splenectomized and irradiated mice

PubMed Central

Inchley, C. J.; Howard, J. G.

1969-01-01

The role of phagocytosed antigen in the production of antibody to bacteriophage T4 has been studied. The ability of mice to give an antibody response to this antigen was first impaired either by splenectomy or by X-irradiation, and then restored by injection of syngeneic lymphoid cells given at various times relative to the injection of T4. In splenectomized animals administration of lymphoid cells had only a marginal effect on the severely depressed response to T4. It was concluded that the presence of an intact spleen is essential to the development of the normal immune response, and that circulating immunocompetent cells are unable to respond to circulating antigen or to antigen sequestered within the liver. On the other hand, in irradiated mice, there was a faster and more complete restoration of the anti-T4 response, confirming the ability of antigen localized within the spleen to stimulate competent cells. It was also found that the immunogenicity of T4 within this organ was not lost at a rate which corresponded to its gross breakdown but persisted without decrease for at least 48 hr. A similar observation was made for sheep red blood cells when this antigen was used in conjunction with T4. PMID:5370054

Cross-reactions of sera from dogs infected with Angiostrongylus vasorum in commercially available Dirofilaria immitis test kits

PubMed Central

2012-01-01

Background Dirofilaria immitis and Angiostrongylus vasorum are both important potentially fatal canine nematodes with overlapping endemic areas, especially in Europe. The preadult and adult stages of both species are living in the Arteria pulmonalis and the right heart, and diagnostically detectable circulating parasite antigens have been demonstrated for both species. For the detection of D. immitis infections, a variety of commercial tests have been developed, however, they have not been evaluated for cross-reactions against circulating antigens of A. vasorum. Methods In this study, potential cross-reactions of sera from 16 dogs, which were experimentally infected with A. vasorum and which had circulating antigens as confirmed by a species-specific ELISA, were evaluated for the detection of A. vasorum antigen in six commercially available D. immitis test kits. Results In three fast tests (Witness® Dirofilaria, SensPERT® Canine Heartworm, SNAP® 4Dx® Plus), all sera were negative. One fast membrane ELISA (SNAP® HTWM RT Test) was positive with four sera (25%), and one serum delivered a non-valid result twice. In the PetChek® HTWM PF Test, depending on the interpretation protocol, 5 or 8 dogs (31.2 – 50%) were positive. With the DiroCHEK®-ELISA, a single A. vasorum-infected dog (6.2%) tested positive. Conclusions Due to potential cross-reactions with A. vasorum in commercially available test kits for the detection of D. immitis antigen, the simultaneous use of highly specific diagnostic methods for the differentiation of these two canine heart worms is recommended. PMID:23148786

Glycoprotein from the liver constitutes the inner layer of the egg envelope (zona pellucida interna) of the fish, Oryzias latipes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hamazaki, T.S.; Nagahama, Y.; Iuchi, I.

1989-05-01

A glycoprotein from the liver, which shares epitopes with chorion (egg envelope or zona pellucida) glycoproteins, is present only in the spawning female fish, Oryzias latipes, under natural conditions. This spawning female-specific (SF) substance is distinct from vitellogenin but closely resembles a major glycoprotein component, ZI-3, of the inner layer (zona radiata interna) of the ovarian egg envelope with respect to some biochemical and immunochemical characteristics. Here we report that the (/sup 125/I)SF substance, injected into the abdominal cavity of the spawning female fish, was rapidly transported by the blood circulation into the ovary and incorporated into the inner layermore » of egg envelope of the growing oocytes. The result strongly suggests that the SF substance from the liver is a precursor substance of the major component, ZI-3, of the inner layer of egg envelope in the fish.« less

National Advisory Committee on Immunization (NACI). Supplementary statement MMR vaccine and anaphylactic hypersensitivity to egg or egg-related antigens.

PubMed

1996-07-15

The fourth edition of the Canadian Immunization Guide (1993) recommends that "persons who have a history of anaphylactic hypersensitivity to hens' eggs (urticaria, swelling of the mouth and throat, difficulty in breathing or hypotension) should not be given measles vaccine except under special precautions." The precautions outlined include skin testing with diluted vaccine and graded challenge vaccination if the skin test is positive. Results of several recent studies have questioned such a cautious approach. NACI has reviewed all available data and revised its guidelines accordingly. The following revised guidelines are a major departure from the previously published recommendations. They will appear in the next edition of the Canadian Immunization Guide. A measles-rubella combination vaccine (Mo-Ru Viraten Berna TM) recently licensed in Canada contains no avian proteins and therefore can be used without regard to egg allergy.

A 1H NMR method for the analysis of antigen-antibody interactions: binding of a peptide fragment of lysozyme to anti-lysozyme monoclonal antibody.

PubMed

Ito, W; Nishimura, M; Sakato, N; Fujio, H; Arata, Y

1987-09-01

A proton nuclear magnetic resonance (NMR) study is reported of the molecular structural basis of antigen-antibody interactions. An immunologically reactive proteolytic fragment corresponding to one of the antigenic regions on hen egg-white lysozyme (HEL) was used in combination with a monoclonal antibody that recognizes this site. Using spin diffusion, we prepared an antibody in which the magnetization of the antigen binding site was saturated by non-specific nuclear Overhauser effect. Under these conditions the effect of the saturation of the antibody was observed to spread over the peptide fragment through the antigen binding site. On the basis of the results obtained for the intermolecular nuclear Overhauser effect, we discuss how the peptide fragment interacts with the antibody. The side chains of aromatic residues, Trp, Tyr, and His, and of ionic residues, especially Arg, Lys, and Glu, are suggested to be important in the antigen-antibody interaction.

Quantifying serum antibody in bird fanciers' hypersensitivity pneumonitis.

PubMed

McSharry, Charles; Dye, George M; Ismail, Tengku; Anderson, Kenneth; Spiers, Elizabeth M; Boyd, Gavin

2006-06-26

Detecting serum antibody against inhaled antigens is an important diagnostic adjunct for hypersensitivity pneumonitis (HP). We sought to validate a quantitative fluorimetric assay testing serum from bird fanciers. Antibody activity was assessed in bird fanciers and control subjects using various avian antigens and serological methods, and the titer was compared with symptoms of HP. IgG antibody against pigeon serum antigens, quantified by fluorimetry, provided a good discriminator of disease. Levels below 10 mg/L were insignificant, and increasing titers were associated with disease. The assay was unaffected by total IgG, autoantibodies and antibody to dietary hen's egg antigens. Antigens from pigeon serum seem sufficient to recognize immune sensitivity to most common pet avian species. Decreasing antibody titers confirmed antigen avoidance. Increasing antibody titer reflected the likelihood of HP, and decreasing titers confirmed antigen avoidance. Quantifying antibody was rapid and the increased sensitivity will improve the rate of false-negative reporting and obviate the need for invasive diagnostic procedures. Automated fluorimetry provides a method for the international standardization of HP serology thereby improving quality control and improving its suitability as a diagnostic adjunct.

Characterizing the histopathology of natural co-infection with Marek's disease virus and subgroup J avian leucosis virus in egg-laying hens.

PubMed

Wen, Yawen; Huang, Qi; Yang, Chengcheng; Pan, Ling; Wang, Guijun; Qi, Kezong; Liu, Hongmei

2018-02-01

Marek's disease virus (MDV) and avian leucosis virus (ALV) are known to cause tumours in egg-laying hens. Here, we investigated the aetiology of tumours in a flock of egg-laying hens vaccinated against MDV. We carried out gross pathology and histopathological examinations of the diseased tissues, identified virus antigen and sequenced viral oncogenes to elucidate the cause of death in 21-22-week-old hens. At necropsy, diseased hens had distinctly swollen livers, spleens, and proventriculus, and white tumour nodules in the liver. The spleen and liver had been infiltrated by lymphoid tumour cells, while the proventriculus had been infiltrated by both lymphoid tumour cells and myeloblastic cells. Subtype J ALV (ALV-J) and MDV were widely distributed in the proventricular gland cells, and the lymphoid tumour cells in the liver and the spleen. In addition, positive ALV-J signals were also observed in parts of the reticular cells in the spleen. MDV and ALV-J antigens were observed in the same foci of the proventricular gland cells; however, the two antigens were not observed in the same foci from the spleen and liver. The amino acid sequence of the AN-1 (the representative liver tumour tissue that was positive for both ALV-J and MDV) Meq protein was highly similar to the very virulent MDV QD2014 from China. Compared to the ALV-J HPRS-103 reference strain, 10 amino acids (224-CTTEWNYYAY-233) were deleted from the gp85 protein of AN-1. We concluded that concurrent infection with MDV and ALV-J contributed to the tumorigenicity observed in the flock.

Detection of Galactomannan Antigenemia in Patients Receiving Piperacillin-Tazobactam and Correlations between In Vitro, In Vivo, and Clinical Properties of the Drug-Antigen Interaction

PubMed Central

Walsh, Thomas J.; Shoham, Shmuel; Petraitiene, Ruta; Sein, Tin; Schaufele, Robert; Kelaher, Amy; Murray, Heidi; Mya-San, Christine; Bacher, John; Petraitis, Vidmantas

2004-01-01

Recent case reports describe patients receiving piperacillin-tazobactam who were found to have circulating galactomannan detected by the double sandwich enzyme-linked immunosorbent assay (ELISA) system, leading to the false presumption of invasive aspergillosis. Since this property of piperacillin-tazobactam and galactomannan ELISA is not well understood, we investigated the in vitro, in vivo, and clinical properties of this interaction. Among the 12 reconstituted antibiotics representing four classes of antibacterial compounds that are commonly used in immunocompromised patients, piperacillin-tazobactam expressed a distinctively high level of galactomannan antigen in vitro (P = 0.001). After intravenous infusion of piperacillin-tazobactam into rabbits, the serum galactomannan index (GMI) in vivo changed significantly (P = 0.0007) from a preinfusion mean baseline value of 0.27 to a mean GMI of 0.83 by 30 min to slowly decline to a mean GMI of 0.44 24 h later. Repeated administration of piperacillin-tazobactam over 7 days resulted in accumulation of circulating galactomannan to a mean peak GMI of 1.31 and a nadir of 0.53. Further studies revealed that the antigen reached a steady state by the third day of administration of piperacillin-tazobactam. Twenty-six hospitalized patients with no evidence of invasive aspergillosis who were receiving antibiotics and ten healthy blood bank donors were studied for expression of circulating galactomannan. Patients (n = 13) receiving piperacillin-tazobactam had significantly greater mean serum GMI values (0.74 ± 0.14) compared to patients (n = 13) receiving other antibiotics (0.14 ± 0.08) and compared to healthy blood bank donors (0.14 ± 0.06) (P < 0.001). Five (38.5%) of thirteen patients receiving piperacillin-tazobactam had serum GMI values > 0.5 compared to none of thirteen subjects receiving other antibiotics (P = 0.039) and to none of ten healthy blood bank donors (P = 0.046). These data demonstrate that among antibiotics that are commonly used in immunocompromised patients, only piperacillin-tazobactam contains significant amounts of galactomannan antigen in vitro, that in animals receiving piperacillin-tazobactam circulating galactomannan antigen accumulates in vivo to significantly increased and sustained levels, and that some but not all patients receiving this antibiotic will demonstrate circulating galactomannan above the threshold considered positive for invasive aspergillosis by the recently licensed double sandwich ELISA. PMID:15472335

[HLA-G: fetomaternal tolerance].

PubMed

Carosella, E D

2000-08-01

HLA-G is a non-classical major histocompatibility complex class I molecule selectively expressed on cytotrophoblasts. We have demonstrated ex vivo (from voluntary pregnancy interruption samples) the protector role of the HLA-G molecule present on the surface of cytotrophoblast cells versus the lysis carried out by the decidual uterine NK cells. This occurs under semi-allogenic conditions (maternal uterine NK cells and their trophoblast counterparts), as well as in allogenic conditions (maternal uterine NK cells and trophoblast cells from different mothers), thus defining the absence of maternal rejection at the moment of the implantation of the fertilized egg during pregnancy. Moreover, the expression of HLA-G on the cytotrophoblasts permits migration in maternal circulation and infiltration of maternal tissue (particularly in the skin), thereby probably creating a general state of tolerance. In the context of heart transplantation, in preliminary studies, we show that the presence of HLA-G in cardiac biopsy tissue prelevated from grafted patients significantly reduces acute rejects and shows an absence of chronic rejects. In the tumour context, the expression of HLA-G protein at the surface of primitive melanoma and metastatic cells confers protection from NK and CTL lytic activity. This suggests that HLA-G expression may impede the elimination of malignant cells by anti-tumour immune effector cells, constituting a newly described mechanism by which tumour cells may evade immunosurveillance. From there on E.D. Carosella introduced the breakthrough concept of 'HLA a tolerance molecule' in the heart of histocompatibility antigens, which had been described up till then as antigenes of defence and rejection, and the dramatic role of HLA-G in immunotolerance.

Hybridoma cell agglutination as a novel test to detect circulating antigen of Schistosoma japonicum.

PubMed

Li, Yong-Long; Liu, Wenqi; Ruppel, Andreas

2003-01-01

We developed a serodiagnostic test which is based on the agglutination of hybridoma cells. In the presence of specific antigen, agglutination of the fixed and stained cells occurs and can be visualized in analogy to traditional erythrocyte agglutination. The procedures were developed with a murine cell line producing a monoclonal antibody against a schistosome gut protein and sera of patients and mice infected with Schistosoma japonicum. This test is capable of detecting circulating antigen during pre-patency in mice infected with 50 cercariae. Its sensitivity was high with acute schistosomiasis japonica (97%, n = 32) and moderate with chronic cases (75%, n = 57). No positive reactions were obtained with healthy persons (n = 78) or patients infected with other parasites (Chlonorchis sinensis, n = 20; Paragonimus westermani, n = 20; Plasmodium vivax, n = 10) or suffering from lupus erythomatodus (n = 5) or mononucleosis (n = 10).

Dynamically correlated mutations drive human Influenza A evolution.

PubMed

Tria, F; Pompei, S; Loreto, V

2013-01-01

Human Influenza A virus undergoes recurrent changes in the hemagglutinin (HA) surface protein, primarily involved in the human antibody recognition. Relevant antigenic changes, enabling the virus to evade host immune response, have been recognized to occur in parallel to multiple mutations at antigenic sites in HA. Yet, the role of correlated mutations (epistasis) in driving the molecular evolution of the virus still represents a challenging puzzle. Further, though circulation at a global geographic level is key for the survival of Influenza A, its role in shaping the viral phylodynamics remains largely unexplored. Here we show, through a sequence based epidemiological model, that epistatic effects between amino acids substitutions, coupled with a reservoir that mimics worldwide circulating viruses, are key determinants that drive human Influenza A evolution. Our approach explains all the up-to-date observations characterizing the evolution of H3N2 subtype, including phylogenetic properties, nucleotide fixation patterns, and composition of antigenic clusters.

Development and Regulation of Novel Influenza Virus Vaccines: A United States Young Scientist Perspective.

PubMed

Khurana, Surender

2018-04-27

Vaccination against influenza is the most effective approach for reducing influenza morbidity and mortality. However, influenza vaccines are unique among all licensed vaccines as they are updated and administered annually to antigenically match the vaccine strains and currently circulating influenza strains. Vaccine efficacy of each selected influenza virus vaccine varies depending on the antigenic match between circulating strains and vaccine strains, as well as the age and health status of the vaccine recipient. Low vaccine effectiveness of seasonal influenza vaccines in recent years provides an impetus to improve current seasonal influenza vaccines, and for development of next-generation influenza vaccines that can provide broader, long-lasting protection against both matching and antigenically diverse influenza strains. This review discusses a perspective on some of the issues and formidable challenges facing the development and regulation of the next-generation influenza vaccines.

Vaccine-associated enhanced respiratory disease is influenced by hemagglutinin and neuraminidase in whole inactivated influenza virus vaccines

USDA-ARS?s Scientific Manuscript database

Multiple subtypes and many antigenic variants of influenza A virus (IAV) co-circulate in swine in the USA, complicating effective use of commercial vaccines to control disease and transmission. Whole inactivated virus (WIV) vaccines may provide partial protection against IAV with substantial antigen...

Antigenic and genetic evolution of contemporary swine H1 influenza viruses in the United States

USDA-ARS?s Scientific Manuscript database

Several lineages of influenza A viruses (IAV) currently circulate in North American pigs. Genetic diversity is further increased by the bidirectional transmission of IAV between swine and humans and the subsequent processes of antigenic shift and drift. Such evolution can be the basis for changes in...

Transmission of lymphocystis disease virus to cultured gilthead seabream, Sparus aurata L., larvae.

PubMed

Cano, I; Valverde, E J; Garcia-Rosado, E; Alonso, M C; Lopez-Jimena, B; Ortiz-Delgado, J B; Borrego, J J; Sarasquete, C; Castro, D

2013-06-01

The transmission of lymphocystis disease virus (LCDV) to gilthead seabream, Sparus aurata L., larvae was investigated using fertilized eggs from a farm with previous reports of lymphocystis disease. LCDV genome was detected by PCR-hybridization in blood samples from 17.5% of the asymptomatic gilthead seabream broodstock analysed. Using the same methodology, eggs spawned from these animals were LCDV positive, as well as larvae hatched from them. The presence of infective viral particles was confirmed by cytopathic effects development on SAF-1 cells. Whole-mount in situ hybridization (ISH) and immunohistochemistry (IHC) showed the presence of LCDV in the epidermis of larvae hatched from LCDV-positive eggs. When fertilized eggs were disinfected with iodine, no viral DNA was detected either in eggs (analysed by PCR-hybridization) or in larvae (PCR-hybridization and ISH). These results suggest the vertical transmission of LCDV, the virus being transmitted on the egg surface. Larvae hatched from disinfected eggs remain LCDV negative during the endotrophic phase, as showed by PCR-hybridization, ISH and IHC. After feeding on LCDV-positive rotifers, viral antigens were observed in the digestive tract, which suggests that viral entry could be achieved via the alimentary canal, and that rotifers can act as a vector in LCDV transmission to gilthead seabream larvae. © 2012 Blackwell Publishing Ltd.

The antigenic complex in HIT binds to B cells via complement and complement receptor 2 (CD21)

PubMed Central

Khandelwal, Sanjay; Lee, Grace M.; Hester, C. Garren; Poncz, Mortimer; McKenzie, Steven E.; Sachais, Bruce S.; Rauova, Lubica; Kelsoe, Garnett; Cines, Douglas B.; Frank, Michael

2016-01-01

Heparin-induced thrombocytopenia is a prothrombotic disorder caused by antibodies to platelet factor 4 (PF4)/heparin complexes. The mechanism that incites such prevalent anti-PF4/heparin antibody production in more than 50% of patients exposed to heparin in some clinical settings is poorly understood. To investigate early events associated with antigen exposure, we first examined the interaction of PF4/heparin complexes with cells circulating in whole blood. In healthy donors, PF4/heparin complexes bind preferentially to B cells (>90% of B cells bind to PF4/heparin in vitro) relative to neutrophils, monocytes, or T cells. Binding of PF4 to B cells is heparin dependent, and PF4/heparin complexes are found on circulating B cells from some, but not all, patients receiving heparin. Given the high proportion of B cells that bind PF4/heparin, we investigated complement as a mechanism for noncognate antigen recognition. Complement is activated by PF4/heparin complexes, co-localizes with antigen on B cells from healthy donors, and is present on antigen-positive B cells in patients receiving heparin. Binding of PF4/heparin complexes to B cells is mediated through the interaction between complement and complement receptor 2 (CR2 [CD21]). To the best of our knowledge, these are the first studies to demonstrate complement activation by PF4/heparin complexes, opsonization of PF4/heparin to B cells via CD21, and the presence of complement activation fragments on circulating B cells in some patients receiving heparin. Given the critical contribution of complement to humoral immunity, our observations provide new mechanistic insights into the immunogenicity of PF4/heparin complexes. PMID:27412887

Predominance of influenza A(H3N2) viruses during the 2016/2017 season in Bulgaria.

PubMed

Korsun, Neli; Angelova, Svetla; Trifonova, Ivelina; Tzotcheva, Iren; Mileva, Sirma; Voleva, Silvia; Georgieva, Irina; Perenovska, Penka

2018-02-01

Influenza viruses are characterised by high variability, which makes them able to cause annual epidemics. The aim of this study is to determine the antigenic and genetic characteristics of influenza viruses circulating in Bulgaria during the 2016/2017 season. The detection and typing/subtyping of influenza viruses were performed using real time RT-PCR. Results of antigenic characterisation, phylogenetic and amino acid sequence analyses of representative influenza strains are presented herein. The 2016/2017 season was characterised by an early start, an exclusive dominance of A(H3N2) viruses accounting for 93 % of total influenza virus detections, and a low circulation of A(H1N1)pdm09 (4.2 %) and type B (2.5 %) viruses. The analysed A(H3N2) viruses belonged to subclades 3C.2a (52 %) and 3C.2a1 (48 %); all studied A(H1N1)pdm09 and B/Victoria-lineage viruses belonged to subclades 6B.1 and 1A, respectively. The amino acid sequence analysis of 56 A(H3N2) isolates revealed the presence of substitutions in 18 positions in haemagglutinin (HA) as compared to the A/Hong Kong/4801/2014 vaccine virus, seven of which occurred in four antigenic sites, together with changes in 23 positions in neuraminidase (NA), and a number of substitutions in internal proteins PB2, PB1, PB1-F2, PA, NP and NS1. Despite the many amino acid substitutions, A(H3N2) viruses remained antigenically similar to the vaccine strain. Substitutions in HA and NA sequences of A(H1N1)pdm09 and B/Victoria-lineage strains were also identified, including in antigenic sites. The results of this study confirm the genetic variability of circulating influenza viruses, particularly A(H3N2), and the need for continued antigenic and molecular surveillance.

Pathogenesis and spectrum of autoimmunity.

PubMed

Perl, Andras

2012-01-01

The immune system specifically recognizes and eliminates foreign antigens and, thus, protects integrity of the host. During maturation of the immune system, tolerance mechanisms develop that prevent or inhibit potentially harmful reactivities to self-antigens. Autoreactive B and T cells that are generated during immune responses are eliminated by apoptosis in the thymus, lymph nodes, or peripheral circulation or actively suppressed by regulatory T cells. However, autoreactive cells may survive due to failure of apoptosis or molecular mimicry, i.e., presentation and recognition of cryptic epitopes of self-antigens, or aberrant lymphokine production. Preservation of the host requires the development of immune responses to foreign antigen and tolerance to self-antigens. Autoimmunity results from a breakdown of tolerance to self-antigens through an interplay of genetic and environmental factors.One of the basic functions of the immune system is to specifically recognize and eliminate foreign antigens and, thus, protect integrity of the host. Through rearrangements and somatic mutations of various gene segments encoding T and B cell receptors and antibody molecules, the immune system acquires tremendous diversity. During maturation of the immune system, recognition of self-antigens plays an important role in shaping the repertoires of immune receptors. Tolerance mechanisms develop that prevent or inhibit potentially harmful reactivities to self-antigens. These self-defense mechanisms are mediated on the levels of central and peripheral tolerance, i.e., autoreactive T cells are either eliminated by apoptosis in the thymus, lymph nodes, or peripheral circulation or actively suppressed by regulatory T cells. Likewise, autoreactive B cells are eliminated in the bone marrow or peripheral lymphoid organs. However, immune responses triggered by foreign antigens may be sustained by molecular mimicry, i.e., presentation and recognition of cryptic epitopes of self-antigens. Further downstream, execution of immune responses depends on the functioning of intracellular signaling networks and the cooperation of many cell types communicating via surface receptors, cytokines, chemokines, and antibody molecules. Therefore, autoimmunity represents the end result of the breakdown of one or multiple basic mechanisms of immune tolerance (Table 1).

Isolation and preliminary characterization of circulating immune complexes from rabbits with experimental syphilis.

PubMed Central

Baughn, R E; Musher, D M

1983-01-01

Immune complexes isolated from sera of rabbits with experimental, disseminated syphilis were found to have sedimentation coefficients greater than 19s. By radioimmunoblot assays, materials precipitated with 2.5% polyethylene glycol or chromatographed on DEAE-Affi-Gel Blue were found to contain albumin, C3, immunoglobulin M (IgM), IgG, and treponemal antigen(s), whereas control materials contained only albumin and IgG. When polyethylene glycol precipitation of immune complexes from syphilitic rabbits was followed by immobilization on protein A and acid elution, radioimmunoblots detected only IgG and treponemal antigen(s). Images PMID:6358025

Multivariate immune defences and fitness in the wild: complex but ecologically important associations among plasma antibodies, health and survival

PubMed Central

Nussey, Daniel H.; Watt, Kathryn A.; Clark, Abigail; Pilkington, Jill G.; Pemberton, Josephine M.; Graham, Andrea L.; McNeilly, Tom N.

2014-01-01

Despite our rapidly advancing mechanistic understanding of vertebrate immunity under controlled laboratory conditions, the links between immunity, infection and fitness under natural conditions remain poorly understood. Antibodies are central to acquired immune responses, and antibody levels circulating in vivo reflect a composite of constitutive and induced functional variants of diverse specificities (e.g. binding antigens from prevalent parasites, self tissues or novel non-self sources). Here, we measured plasma concentrations of 11 different antibody types in adult females from an unmanaged population of Soay sheep on St Kilda. Correlations among antibody measures were generally positive but weak, and eight of the measures independently predicted body mass, strongyle parasite egg count or survival over the subsequent winter. These independent and, in some cases, antagonistic relationships point to important multivariate immunological heterogeneities affecting organismal health and fitness in natural systems. Notably, we identified a strong positive association between anti-nematode immunoglobulin (Ig) G antibodies in summer and subsequent over-winter survival, providing rare evidence for a fitness benefit of helminth-specific immunity under natural conditions. Our results highlight both the evolutionary and ecological importance and the complex nature of the immune phenotype in the wild. PMID:24500168

The cooling time of fertile chicken eggs at different stages of incubation.

PubMed

Mortola, Jacopo P; Gaonac'h-Lovejoy, Vanda

2016-01-01

We asked whether or not the thermal characteristics of fertile avian eggs changed throughout incubation. The cooling and warming times, expressed by the time constant τ of the egg temperature response to a rapid change in ambient temperature, were measured in fertile chicken eggs at early (E7), intermediate (E11) and late (E20) stages of embryonic development. Same measurements were conducted on eggs emptied of their content and refilled with water by various amounts. The results indicated that (1) the τ of a freshly laid egg was ~50 min; (2) τ decreased linearly with the drop in egg water volume; (3) the dry eggshell had almost no thermal resistance but its wet inner membrane contributed about one-third to the stability of egg temperature; (4) the egg constituents (yolk, albumen and embryonic tissues) and the chorioallantoic circulation had no measurable effect on τ; (5) the presence of an air pocket equivalent in volume to the air cell of fertile eggs reduced τ by about 3 min (E7), 5 min (E11) and 11 min (E20). Hence, in response to warming the egg τ at E20 was slightly shorter than at E7. In response to cooling, the egg τ at E20 was similar to, or longer than, E7 because embryonic thermogenesis (evaluated by measurements of oxygen consumption during cold) offset the reduction in τ introduced by the air cell. In conclusion, until the onset of thermogenesis the thermal behavior of a fertile egg is closely approximated by that of a water-filled egg with an air volume equivalent to the air cell. It is possible to estimate the cooling τ of avian eggs of different species from their weight and incubation time. Copyright © 2015 Elsevier Ltd. All rights reserved.

Detection of rabies-specific antigens by egg yolk antibody (IgY) to the recombinant rabies virus proteins produced in Escherichia coli.

PubMed

Motoi, Yurie; Inoue, Satoshi; Hatta, Hajime; Sato, Kozue; Morimoto, Kinjiro; Yamada, Akio

2005-04-01

We obtained rabies-specific egg yolk antibodies (IgY) by immunizing hens with recombinant His-tagged nucleoprotein and phosphoprotein (rN, rP) of the rabies virus (CVS-11 strain) expressed in Escherichia coli. The anti-rN and rP IgY were shown to bind specifically to the respective proteins of the CVS-11 strain of rabies virus by Western blotting, immune fluorescent assay and immunohistochemistry, indicating that IgY to rabies recombinant proteins could serve as a reagent for diagnosis of rabies virus infection.

Identification of super-infected Aedes triseriatus mosquitoes collected as eggs from the field and partial characterization of the infecting La Crosse viruses

PubMed Central

2010-01-01

Background La Crosse virus (LACV) is a pathogenic arbovirus that is transovarially transmitted by Aedes triseriatus mosquitoes and overwinters in diapausing eggs. However, previous models predicted transovarial transmission (TOT) to be insufficient to maintain LACV in nature. Results To investigate this issue, we reared mosquitoes from field-collected eggs and assayed adults individually for LACV antigen, viral RNA by RT-PCR, and infectious virus. The mosquitoes had three distinct infection phenotypes: 1) super infected (SI+) mosquitoes contained infectious virus, large accumulations of viral antigen and RNA and comprised 17 of 17,825 (0.09%) of assayed mosquitoes, 2) infected mosquitoes (I+) contained no detectable infectious virus, lesser amounts of viral antigen and RNA, and comprised 3.7% of mosquitoes, and 3) non-infected mosquitoes (I-) contained no detectable viral antigen, RNA, or infectious virus and comprised 96.21% of mosquitoes. SI+ mosquitoes were recovered in consecutive years at one field site, suggesting that lineages of TOT stably-infected and geographically isolated Ae. triseriatus exist in nature. Analyses of LACV genomes showed that SI+ isolates are not monophyletic nor phylogenetically distinct and that synonymous substitution rates exceed replacement rates in all genes and isolates. Analysis of singleton versus shared mutations (Fu and Li's F*) revealed that the SI+ LACV M segment, with a large and significant excess of intermediate-frequency alleles, evolves through disruptive selection that maintains SI+ alleles at higher frequencies than the average mutation rate. A QTN in the LACV NSm gene was detected in SI+ mosquitoes, but not in I+ mosquitoes. Four amino acid changes were detected in the LACV NSm gene from SI+ but not I+ mosquitoes from one site, and may condition vector super infection. In contrast to NSm, the NSs sequences of LACV from SI+ and I+ mosquitoes were identical. Conclusions SI+ mosquitoes may represent stabilized infections of Ae. triseriatus mosquitoes, which could maintain LACV in nature. A gene-for-gene interaction involving the viral NSm gene and a vector innate immune response gene may condition stabilized infection. PMID:20412589

Crystal structure of a shark single-domain antibody V region in complex with lysozyme.

PubMed

Stanfield, Robyn L; Dooley, Helen; Flajnik, Martin F; Wilson, Ian A

2004-09-17

Cartilaginous fish are the phylogenetically oldest living organisms known to possess components of the vertebrate adaptive immune system. Key to their immune response are heavy-chain, homodimeric immunoglobulins called new antigen receptors (IgNARs), in which the variable (V) domains recognize antigens with only a single immunoglobulin domain, akin to camelid heavy-chain V domains. The 1.45 angstrom resolution crystal structure of the type I IgNAR V domain in complex with hen egg-white lysozyme (HEL) reveals a minimal antigen-binding domain that contains only two of the three conventional complementarity-determining regions but still binds HEL with nanomolar affinity by means of a binding interface comparable in size to conventional antibodies.

Maturation of Shark Single-Domain (IgNAR) Antibodies: Evidence for Induced-Fit Binding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stanfield, R.L.; Dooley, H.; Verdino, P.

2007-07-13

Sharks express an unusual heavy-chain isotype called IgNAR, whose variable regions bind antigen as independent soluble domains. To further probe affinity maturation of the IgNAR response, we structurally characterized the germline and somatically matured versions of a type II variable (V) region, both in the presence and absence of its antigen, hen egg-white lysozyme. Despite a disulfide bond linking complementarity determining regions (CDRs) 1 and 3, both germline and somatically matured V regions displayed significant structural changes in these CDRs upon complex formation with antigen. Somatic mutations in the IgNAR V region serve to increase the number of contacts withmore » antigen, as reflected by a tenfold increase in affinity, and one of these mutations appears to stabilize the CDR3 region. In addition, a residue in the HV4 loop plays an important role in antibody-antigen interaction, consistent with the high rate of somatic mutations in this non-CDR loop.« less

Selection and characterization of naturally occurring single-domain (IgNAR) antibody fragments from immunized sharks by phage display.

PubMed

Dooley, Helen; Flajnik, Martin F; Porter, Andrew J

2003-09-01

The novel immunoglobulin isotype novel antigen receptor (IgNAR) is found in cartilaginous fish and is composed of a heavy-chain homodimer that does not associate with light chains. The variable regions of IgNAR function as independent domains similar to those found in the heavy-chain immunoglobulins of Camelids. Here, we describe the successful cloning and generation of a phage-displayed, single-domain library based upon the variable domain of IgNAR. Selection of such a library generated from nurse sharks (Ginglymostoma cirratum) immunized with the model antigen hen egg-white lysozyme (HEL) enabled the successful isolation of intact antigen-specific binders matured in vivo. The selected variable domains were shown to be functionally expressed in Escherichia coli, extremely stable, and bind to antigen specifically with an affinity in the nanomolar range. This approach can therefore be considered as an alternative route for the isolation of minimal antigen-binding fragments with favorable characteristics.

A structural basis for antigen recognition by the T cell-like lymphocytes of sea lamprey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deng, Lu; Velikovsky, C. Alejandro; Xu, Gang

Adaptive immunity in jawless vertebrates is mediated by leucine-rich repeat proteins called 'variable lymphocyte receptors' (VLRs). Two types of VLR (A and B) are expressed by mutually exclusive lymphocyte populations in lamprey. VLRB lymphocytes resemble the B cells of jawed vertebrates; VLRA lymphocytes are similar to T cells. We determined the structure of a high-affinity VLRA isolated from lamprey immunized with hen egg white lysozyme (HEL) in unbound and antigen-bound forms. The VLRA-HEL complex demonstrates that certain VLRAs, like {gamma}{delta} T-cell receptors (TCRs) but unlike {alpha}{beta} TCRs, can recognize antigens directly, without a requirement for processing or antigen-presenting molecules. Thus,more » these VLRAs feature the nanomolar affinities of antibodies, the direct recognition of unprocessed antigens of both antibodies and {gamma}{delta} TCRs, and the exclusive expression on the lymphocyte surface that is unique to {alpha}{beta} and {gamma}{delta} TCRs.« less

Isolation and Characterization of a Novel Tembusu Virus Circulating in Muscovy Ducks in South China.

PubMed

Yan, Z; Shen, H; Wang, Z; Lin, W; Xie, Q; Bi, Y; Chen, F

2017-10-01

Duck Tembusu virus (DTMUV) is an infectious pathogen that can cause epidemics in egg-laying ducks. Here, we isolated and characterized a DTMUV, designated GDLH01, thought to be responsible for the noticeable egg drop in Muscovy duck flocks in South China since 2011. The genome sequence of GDLH01 shared 97-99% homology with other avian-origin Tembusu viruses, and 99.5% homology with the mosquito-borne strain SDMS recently reported in China. Phylogenetic analysis based on the nucleotide sequence of the entire open reading frame confirmed that the isolate was of avian origin and closely related to a mosquito-borne strain. Our findings characterize a novel Tembusu virus circulating in Muscovy ducks in South China and emphasize the importance of reinforcing biosecurity measures and developing vaccines to prevent the spread of this viral pathogen. © 2016 Blackwell Verlag GmbH.

Schistosoma mansoni and HIV infection in a Ugandan population with high HIV and helminth prevalence.

PubMed

Sanya, Richard E; Muhangi, Lawrence; Nampijja, Margaret; Nannozi, Victoria; Nakawungu, Prossy Kabuubi; Abayo, Elson; Webb, Emily L; Elliott, Alison M

2015-09-01

Recent reports suggest that Schistosoma infection may increase the risk of acquiring human immunodeficiency virus (HIV). We used data from a large cross-sectional study to investigate whether Schistosoma mansoni infection is associated with increased HIV prevalence. We conducted a household survey of residents in island fishing communities in Mukono district, Uganda, between October 2012 and July 2013. HIV status was assessed using rapid test kits. Kato-Katz (KK) stool tests and urine-circulating cathodic antigen (CCA) were used to test for Schistosoma infection. Multivariable logistic regression, allowing for the survey design, was used to investigate the association between S. mansoni infection and HIV infection. Data from 1412 participants aged 13 years and older were analysed (mean age 30.3 years, 45% female). The prevalence of HIV was 17.3%. Using the stool Kato-Katz technique on a single sample, S. mansoni infection was detected in 57.2% (719/1257) of participants; urine CCA was positive in 73.8% (478/650) of those tested. S. mansoni infection was not associated with HIV infection. [KK (aOR = 1.04; 95% CI: 0.74-1.47, P = 0.81), CCA (aOR = 1.53; 95% CI: 0.78-3.00, P = 0.19)]. The median S. mansoni egg count per gram was lower in the HIV-positive participants (P = 0.005). These results add to the evidence that S. mansoni has little effect on HIV transmission, but may influence egg excretion. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

Detection of schistosomiasis in an area directly affected by the São Francisco River large-scale water transposition project in the Northeast of Brazil.

PubMed

Silva, José Damião da; Pinheiro, Marta Cristhiany Cunha; Sousa, Mariana Silva; Gomes, Vivian da Silva; Castro, Issis Maria Nogueira de; Ramos, Alberto Novaes; Bezerra, Fernando Schemelzer de Moraes

2017-01-01

The development of the São Francisco River Integration Project [Projeto de Integração do Rio São Francisco (PISF)] in the State of Ceará, Brazil, has resulted in environmental and socioeconomic changes with potential risks to public health. We aimed to determine the presence of Schistosoma mansoni infections in schoolchildren (aged 7-14 years) and workers from the construction site in an area under the direct influence of the PISF in the municipality of Brejo Santo-CE, to aid in the prevention and control of schistosomiasis. We conducted a cross-sectional study using two S. mansoni-detection methods: detection of S. mansoni eggs by the Kato-Katz parasitological method in stool samples (assessed in triplicate for each sample) and S. mansoni circulating cathodic antigen by the point-of-care immunochromatographic rapid test (POC-CCA) in urine. In general, the positivity rates for S. mansoni detection were 1.9% (2/106) among schoolchildren and 2.9% (4/138) among workers. No child had evidence of S. mansoni eggs in their stools; 1.9% tested positive by the POC-CCA method. Among workers, two (1.4%) tested positive by the Kato-Katz test and three (2.2%) by the POC-CCA test. If the POC-CCA test results that were scored as traces were considered negative, then the positivity rates dropped to 0.9% and 0.7% for schoolchildren and workers, respectively. The active transmission of schistosomiasis in a region covered by the PISF was recognized, reinforcing the necessity to consolidate surveillance and control actions, as well as structural sanitation measures to reverse the social determinants of the disease.

Nonclassical T Cells and Their Antigens in Tuberculosis

PubMed Central

De Libero, Gennaro; Singhal, Amit; Lepore, Marco; Mori, Lucia

2014-01-01

T cells that recognize nonpeptidic antigens, and thereby are identified as nonclassical, represent important yet poorly characterized effectors of the immune response. They are present in large numbers in circulating blood and tissues and are as abundant as T cells recognizing peptide antigens. Nonclassical T cells exert multiple functions including immunoregulation, tumor control, and protection against infections. They recognize complexes of nonpeptidic antigens such as lipid and glycolipid molecules, vitamin B2 precursors, and phosphorylated metabolites of the mevalonate pathway. Each of these antigens is presented by antigen-presenting molecules other than major histocompatibility complex (MHC), including CD1, MHC class I–related molecule 1 (MR1), and butyrophilin 3A1 (BTN3A1) molecules. Here, we discuss how nonclassical T cells participate in the recognition of mycobacterial antigens and in the mycobacterial-specific immune response. PMID:25059739

Genetic Analyses Reveal Differences in the VP7 and VP4 Antigenic Epitopes between Human Rotaviruses Circulating in Belgium and Rotaviruses in Rotarix and RotaTeq

PubMed Central

Zeller, Mark; Patton, John T.; Heylen, Elisabeth; De Coster, Sarah; Ciarlet, Max; Van Ranst, Marc

2012-01-01

Two live-attenuated rotavirus group A (RVA) vaccines, Rotarix (G1P[8]) and RotaTeq (G1-G4, P[8]), have been successfully introduced in many countries worldwide, including Belgium. The parental RVA strains used to generate the vaccines were isolated more than 20 years ago in France (G4 parental strain in RotaTeq) and the United States (all other parental strains). At present, little is known about the relationship between currently circulating human RVAs and the vaccine strains. In this study, we determined sequences for the VP7 and VP4 outer capsid proteins of representative G1P[8], G2P[4], G3P[8], G4P[8], G9P[8], and G12P[8] RVAs circulating in Belgium during 2007 to 2009. The analyses showed that multiple amino acid differences existed between the VP7 and VP4 antigenic epitopes of the vaccine viruses and the Belgian isolates, regardless of their G and P genotypes. However, the highest variability was observed among the circulating G1P[8] RVA strains and the G1 and P[8] components of both RVA vaccines. In particular, RVA strains of the P[8] lineage 4 (OP354-like) showed a significant number of amino acid differences with the P[8] VP4 of both vaccines. In addition, the circulating Belgian G3 RVA strains were found to possibly possess an extra N-linked glycosylation site compared to the G3 RVA vaccine strain of RotaTeq. These results indicate that the antigenic epitopes of RVA strains contained in the vaccines differ substantially from those of the currently circulating RVA strains in Belgium. Over time, these differences might result in selection for strains that escape the RVA neutralizing-antibody pressure induced by vaccines. PMID:22189107

Genetic analyses reveal differences in the VP7 and VP4 antigenic epitopes between human rotaviruses circulating in Belgium and rotaviruses in Rotarix and RotaTeq.

PubMed

Zeller, Mark; Patton, John T; Heylen, Elisabeth; De Coster, Sarah; Ciarlet, Max; Van Ranst, Marc; Matthijnssens, Jelle

2012-03-01

Two live-attenuated rotavirus group A (RVA) vaccines, Rotarix (G1P[8]) and RotaTeq (G1-G4, P[8]), have been successfully introduced in many countries worldwide, including Belgium. The parental RVA strains used to generate the vaccines were isolated more than 20 years ago in France (G4 parental strain in RotaTeq) and the United States (all other parental strains). At present, little is known about the relationship between currently circulating human RVAs and the vaccine strains. In this study, we determined sequences for the VP7 and VP4 outer capsid proteins of representative G1P[8], G2P[4], G3P[8], G4P[8], G9P[8], and G12P[8] RVAs circulating in Belgium during 2007 to 2009. The analyses showed that multiple amino acid differences existed between the VP7 and VP4 antigenic epitopes of the vaccine viruses and the Belgian isolates, regardless of their G and P genotypes. However, the highest variability was observed among the circulating G1P[8] RVA strains and the G1 and P[8] components of both RVA vaccines. In particular, RVA strains of the P[8] lineage 4 (OP354-like) showed a significant number of amino acid differences with the P[8] VP4 of both vaccines. In addition, the circulating Belgian G3 RVA strains were found to possibly possess an extra N-linked glycosylation site compared to the G3 RVA vaccine strain of RotaTeq. These results indicate that the antigenic epitopes of RVA strains contained in the vaccines differ substantially from those of the currently circulating RVA strains in Belgium. Over time, these differences might result in selection for strains that escape the RVA neutralizing-antibody pressure induced by vaccines.

Ovarian tumor antigens.

PubMed

Bhattacharya, M; Barlow, J J

1978-09-01

Evidence has been reported for at least two common tumor-associated antigens, or antigenic determinants, in human cystadenocarcinomas of the ovary that are apparently absent in tissues of normal reproductive organs. These antigenic determinants are immunologically distinct from carcinoembryonic antigen, alpha-fetoprotein, ferritins and histocompatibility antigens. One of these two ovarian cystadenocarcinoma-associated antigens (OCAA) is not detectable in any ovarian carcinomas except serous or mucinous types, other gynecologic or nongynecologic malignancies thus far tested, while the second antigen is present in about 90% of all gynecologic tumors and occasionally in breast and colon tumors. OCAA has been purified and partially characterized. It is a high molecular weight glycoprotein which carries the unique ovarian tumor-specific antigenic determinant along with some normal cross-reacting determinants. High levels of this glycoprotein antigen have been detected in the sera of ovarian cancer patients with advanced disease by the radioimmunoassay inhibition technique. The serial determination of circulating OCAA appeared to correlate with tumor volume as well as the clinical status of the patients.

CK2 phosphorylation of Schistosoma mansoni HMGB1 protein regulates its cellular traffic and secretion but not its DNA transactions.

PubMed

de Abreu da Silva, Isabel Caetano; Carneiro, Vitor Coutinho; Maciel, Renata de Moraes; da Costa, Rodrigo Furtado Madeiro; Furtado, Daniel Rodrigues; de Oliveira, Francisco Meirelles Bastos; da Silva-Neto, Mário Alberto Cardoso; Rumjanek, Franklin David; Fantappié, Marcelo Rosado

2011-01-01

The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1), a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1) is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space. We showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated. We showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis.

Genotypic evolution and antigenicity of H9N2 influenza viruses in Shanghai, China.

PubMed

Ge, Feifei; Li, Xin; Ju, Houbin; Yang, Dequan; Liu, Jian; Qi, Xinyong; Wang, Jian; Yang, Xianchao; Qiu, Yafeng; Liu, Peihong; Zhou, Jinping

2016-06-01

H9N2 influenza viruses have been circulating in China since 1994, but a systematic investigation of H9N2 in Shanghai has not previously been undertaken. Here, using 14 viruses we isolated from poultry and pigs in Shanghai during 2002 and 2006-2014, together with the commercial vaccine A/chicken/Shanghai/F/1998 (Ck/SH/F/98), we analyzed the evolution of H9N2 influenza viruses in Shanghai and showed that all 14 isolates originated from Ck/SH/F/98 antigenically. We evaluated the immune protection efficiency of the vaccine. Our findings demonstrate that H9N2 viruses in Shanghai have undergone extensive reassortment. Various genotypes emerged in 2002, 2006 and 2007, while during 2009-2014 only one genotype was found. Four antigenic groups, A-D, could be identified among the 14 isolates and a variety of antigenically distinct H9N2-virus-derived avian influenza viruses (AIVs) circulated simultaneously in Shanghai during this period. Challenge experiments using vaccinated chickens indicated that the vaccine prevented shedding of antigenic group A and B viruses, but not those of the more recent groups C and D. Genetic analysis showed that compared to the vaccine strain, representative viruses of antigenic groups C and D possess greater numbers of amino acid substitutions in the hemagglutinin (HA) protein than viruses in antigenic groups A and B. Many of these substitutions are located in antigenic sites. Our results indicate that the persistence of H9N2 AIV in China might be due to incomplete vaccine protection and that the avian influenza vaccine should be regularly evaluated and updated to maintain optimal protection.

Technology transfer and scale-up of the Flublok recombinant hemagglutinin (HA) influenza vaccine manufacturing process.

PubMed

Buckland, Barry; Boulanger, Robert; Fino, Mireli; Srivastava, Indresh; Holtz, Kathy; Khramtsov, Nikolai; McPherson, Clifton; Meghrous, Jamal; Kubera, Paul; Cox, Manon M J

2014-09-22

Multiple different hemagglutinin (HA) protein antigens have been reproducibly manufactured at the 650L scale by Protein Sciences Corporation (PSC) based on an insect cell culture with baculovirus infection. Significantly, these HA protein antigens were produced by the same Universal Manufacturing process as described in the biological license application (BLA) for the first recombinant influenza vaccine approved by the FDA (Flublok). The technology is uniquely designed so that a change in vaccine composition can be readily accommodated from one HA protein antigen to another one. Here we present a vaccine candidate to combat the recently emerged H7N9 virus as an example starting with the genetic sequence for the required HA, creation of the baculovirus and ending with purified protein antigen (or vaccine component) at the 10L scale accomplished within 38 days under GMP conditions. The same process performance is being achieved at the 2L, 10L, 100L, 650L and 2500L scale. An illustration is given of how the technology was transferred from the benchmark 650L scale facility to a retrofitted microbial facility at the 2500L scale within 100 days which includes the time for facility engineering changes. The successful development, technology transfer and scale-up of the Flublok process has major implications for being ready to make vaccine rapidly on a worldwide scale as a defense against pandemic influenza. The technology described does not have the same vulnerability to mutations in the egg adapted strain, and resulting loss in vaccine efficacy, faced by egg based manufacture. Copyright © 2014 Elsevier Ltd. All rights reserved.

Use of recombinant calreticulin and cercarial transformation fluid (CTF) in the serodiagnosis of Schistosoma mansoni.

PubMed

El Aswad, Bahaa El Deen Wade; Doenhoff, Michael J; El Hadidi, Abeer Shawky; Schwaeble, Wilhelm J; Lynch, Nicholas J

2011-03-01

Schistosomiasis is traditionally diagnosed by microscopic detection of ova in stool samples, but this method is labour intensive and its sensitivity is limited by low and variable egg secretion in many patients. An alternative is an ELISA using Schistosoma mansoni soluble egg antigen (SEA) to detect anti-schistosome antibody in patient samples. SEA is a good diagnostic marker in non-endemic regions but is of limited value in endemic regions, mainly because of its high cost and limited specificity. Here we assess seven novel antigens for the detection of S. mansoni antibody in an endemic region (the Northern Nile Delta). Using recombinant S. mansoni calreticulin (CRT) and fragments thereof, anti-CRT antibodies were detected in the majority of 97 patients sera. The diagnostic value of some of these antigens was, however, limited by the presence of cross-reacting antibody in the healthy controls, even those recruited in non-endemic areas. Cercarial transformation fluid (CTF), a supernatant that contains soluble material released by the cercariae upon transformation to the schistosomula, is cheaper and easier to produce than SEA. An ELISA using CTF as the detection antigen had a sensitivity of 89.7% and an estimated specificity of 100% when used in non-endemic regions, matching the performance of the established SEA ELISA. CTF was substantially more specific than SEA for diagnosis in the endemic region, and less susceptible than SEA to cross-reacting antibody in the sera of controls with other protozoan and metazoan infections. Copyright © 2010 Elsevier GmbH. All rights reserved.

Ovarian Cancer, Stem Cells, and Bioreactors

DTIC Science & Technology

2009-10-01

also indirectly assessed by measuring CEA and CA125 levels in the circulating medium. CEA and CA125, belonging to the CEA antigen family, are...with OVC#6 could not be detected. The low level of CA125 may be due to a dilution of the protein in the circulating medium as protein concentrations...lower than 8.7U/ml are below the assay sensitivity. Unfortunately, we have been unable to obtain the CA125 circulating level for either patient so

Antigenic Distance Measurements for Seasonal Influenza Vaccine Selection

PubMed Central

Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

2011-01-01

Influenza vaccination is one of the major options to counteract the effects of influenza diseases. Selection of an effective vaccine strain is the key to the success of an effective vaccination program since vaccine protection can only be achieved when the selected influenza vaccine strain matches the antigenic variants causing future outbreaks. Identification of an antigenic variant is the first step to determine whether vaccine strain needs to be updated. Antigenic distance derived from immunological assays, such as hemagglutination inhibition, is commonly used to measure the antigenic closeness between circulating strains and the current influenza vaccine strain. Thus, consensus on an explicit and robust antigenic distance measurement is critical in influenza surveillance. Based on the current seasonal influenza surveillance procedure, we propose and compare three antigenic distance measurements, including Average antigenic distance (A-distance), Mutual antigenic distance (M-distance), and Largest antigenic distance (L-distance). With the assistance of influenza antigenic cartography, our simulation results demonstrated that M-distance is a robust influenza antigenic distance measurement. Experimental results on both simulation and seasonal influenza surveillance data demonstrate that M-distance can be effectively utilized in influenza vaccine strain selection. PMID:22063385

Mass spectrometric characterization of circulating and functional antigens derived from piperacillin in patients with cystic fibrosis1

PubMed Central

Whitaker, Paul; Meng, Xiaoli; Lavergne, Sidonie N.; El-Ghaiesh, Sabah; Monshi, Manal; Earnshaw, Caroline; Peckham, Daniel; Gooi, Jimmy; Conway, Steve; Pirmohamed, Munir; Jenkins, Rosalind E.; Naisbitt, Dean J.; Park, B. Kevin

2011-01-01

A mechanistic understanding of the relationship between the chemistry of drug antigen formation and immune function is lacking. Thus, mass spectrometric methods were employed to detect and fully characterize circulating antigens derived from piperacillin in patients undergoing therapy and the nature of the drug derived-epitopes on protein which can function as an antigen to stimulate T-cells. Albumin modification with piperacillin in vitro resulted in the formation of two distinct haptens, one formed directly from piperacillin and a second in which the dioxopiperazine ring had undergone hydrolysis. Modification was time- and concentration-dependent, with selective modification of Lys541 observed at low concentrations, whereas at higher concentrations up to 13/59 lysine residues were modified, four of which (Lys190, 195, 432 and 541) were detected in patients’ plasma. Piperacillin-specific T-lymphocyte responses (proliferation, cytokines and granzyme-B release) were detected ex vivo with cells from hypersensitive patients, and analysis of incubation medium showed that modification of the same lysine residues in albumin occurred in situ. The antigenicity of piperacillin-modified albumin was confirmed by stimulation of T-cells with characterized synthetic conjugates. Analysis of minimally-modified T-cell stimulatory albumin conjugates revealed peptide sequences incorporating Lys190, 432 and 541 as principal functional epitopes for T-cells. This study has characterized the multiple haptenic structures on albumin in patients, and showed that they constitute functional antigenic determinants for T-cells. PMID:21606251

Stress and parental care in a wild Teleost fish: insights from exogenous supraphysiological cortisol implants.

PubMed

O'Connor, Constance M; Gilmour, Kathleen M; Arlinghaus, Robert; Van Der Kraak, Glen; Cooke, Steven J

2009-01-01

Male largemouth bass (Micropterus salmoides) provide sole parental care over a 4-6-wk period to a single brood, fanning the eggs to keep them oxygenated and free of silt and defending the brood until the offspring develop antipredator tactics. During this period, fish are highly active and have few opportunities for feeding, so this activity is energetically costly. To understand some of the consequences of stress during this challenging period, we injected fish with cortisol suspended in coconut oil to experimentally raise circulating cortisol in parental males for the first week of the parental care period. We compared parental care behavior between cortisol-treated, sham-treated (injected only with coconut oil), and control parental males. We further compared physiological parameters associated with metabolism and reproductive function between cortisol-treated and control males. The cortisol injections resulted in supraphysiological levels of circulating plasma cortisol, giving us insight into potential maximal effects of stress during parental care. At these supraphysiological levels, the cortisol-treated fish displayed higher concentrations of circulating glucose and cholesterol and lower concentrations of circulating triglycerides when compared with control fish, with no change in plasma concentrations of total protein. Plasma concentrations of androgen were similarly unaffected by cortisol treatment. In the short term (initial 1-2 wk), parental care of eggs and egg-sac fry was maintained by all groups, with no differences observed in behavior (e.g., tending, vigilance, defense) among the groups. However, the cortisol-treated fish abandoned their offspring at a higher rate than in the control or sham groups. The fish treated with cortisol also tended to develop external Saprolegnian infections, indicative of compromised immune function. These data demonstrate that exogenous cortisol elevation during parental care results in changes in energy use and a decrease in immune function. Interestingly, the data also suggest resistance to stress during parental care in largemouth bass, with no changes in parental care behavior before abandonment.

Transfer of Maternal Antibodies against Avian Influenza Virus in Mallards (Anas platyrhynchos)

PubMed Central

van Dijk, Jacintha G. B.; Mateman, A. Christa; Klaassen, Marcel

2014-01-01

Maternal antibodies protect chicks from infection with pathogens early in life and may impact pathogen dynamics due to the alteration of the proportion of susceptible individuals in a population. We investigated the transfer of maternal antibodies against avian influenza virus (AIV) in a key AIV host species, the mallard (Anas platyrhynchos). Combining observations in both the field and in mallards kept in captivity, we connected maternal AIV antibody concentrations in eggs to (i) female body condition, (ii) female AIV antibody concentration, (iii) egg laying order, (iv) egg size and (v) embryo sex. We applied maternity analysis to the eggs collected in the field to account for intraspecific nest parasitism, which is reportedly high in Anseriformes, detecting parasitic eggs in one out of eight clutches. AIV antibody prevalence in free-living and captive females was respectively 48% and 56%, with 43% and 24% of the eggs receiving these antibodies maternally. In both field and captive study, maternal AIV antibody concentrations in egg yolk correlated positively with circulating AIV antibody concentrations in females. In the captive study, yolk AIV antibody concentrations correlated positively with egg laying order. Female body mass and egg size from the field and captive study, and embryos sex from the field study were not associated with maternal AIV antibody concentrations in eggs. Our study indicates that maternal AIV antibody transfer may potentially play an important role in shaping AIV infection dynamics in mallards. PMID:25386907

Evaluation of Gastrothylax crumenifer antigenic preparation in serodiagnosis of paramphistomiasis in sheep.

PubMed

Ahmad, Tariq; Reshi, Mohammad Latif; Cheshti, M Z; Tanveer, Syed; Shah, Zaffar Amin; Fomada, Bashir Ahmad; Raina, O K

2014-04-01

An evaluation of Gastrothylax crumenifer crude antigen preparation viz., Somatic Antigen (SAg), Excretory Secretory Antigen (ESAg) and Egg Antigen (EAg) in serodiagnosis of disease was undertaken. Test sera samples were obtained from 30 Paramphistomiasis Positive and 30 Gastrothylax free sheep slaughtered at Hazratbal Kashmir. The referral antigenic preparation were evaluated against Paramphistomiasis positive sera, via., control negative sera, using double immunodiffusion test (DID), (IEP) Immunoelectrophoretic assay and ELISA. The performance of referral antigens, as assessed from percent sensitivity and specificity, revealed an increasing trend from DID (Double immunodiffusion-An immunological technique used in the detection, identification and quantification of antibodies and antigens) to IEP (immunoelectrophoresis-A general name for a number of biochemical methods for separation and characterization of proteins based on electrophoresis and reaction with antibodies), followed by ELISA, detecting higher number of sheep positive for paramphistomiasis. In ELISA the ESAg and SAg were evaluated as most reactive antigens with no significant difference and EAg was the least antigenic. In IEP, EAg had the higher sensitivity (60%) and analogous specificity of SAg and ESAg. The formation of the preceptin lines in the proximity to EAg containing wells (cathode end) in IEP was suggestive of higher molecular weight of G. crumenifer specific protein molecules with slower rate of migration. Purification and characterization of G. crumenifer and identification of specific antigenic molecules, particularly in EAg has been suggested for qualitative improvement of diagnostic value of the antigens in the tests used here in.

The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection

PubMed Central

Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

2017-01-01

The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC. PMID:28795022

The potency of chicken egg yolk immunoglobulin (IgY) specific as immunotherapy to Mycobacterium tuberculosis infection.

PubMed

Sudjarwo, Sri Agus; Eraiko, Koerniasari; Sudjarwo, Giftania Wardani; Koerniasari

2017-01-01

The aim of this study was to characterize of chicken egg yolk immunoglobulins (IgYs) specific as immunotherapy to Mycobacterium tuberculosis complex (MTBC) infection. Lohmann laying hens were immunized intramuscularly with antigenic of MTBC. Egg yolk was separated from egg white, and IgY antibody was then purified by multiple polyethylene glycols 6000 extraction and ammonium sulfate purification steps. The IgY anti-MTBC concentration in egg yolk increased at 2 weeks and it reached a maximum at 4 weeks after immunization. After 6 weeks, the levels of IgY anti-MTBC decreased gradually. The antibody of MTBC was detected and produces a specific line of precipitation in agar gel precipitation test beginning the week 2 after the first immunization. Analysis of results obtained with ELISA showed a significant increase in the MTBC specific antibodies after 2 weeks and reached a plateau at 4 weeks from the booster immunization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the IgY preparation to be pure and dissociated into protein bands with molecular weights of 112, 78, 69, 49, and 28 kDa and Western blot analysis shown the presence of anti-MTBC IgY in egg yolks, with molecular weights of approximately 78 kDa. These results suggested that egg yolk could be a practical strategy in large-scale production of specific anti-MTBC IgY for immunotherapy of TBC.

Antigenicity and Immunogenicity in HIV-1 Antibody-Based Vaccine Design

PubMed Central

Kong, Leopold; Sattentau, Quentin J

2012-01-01

Neutralizing antibodies can protect from infection by immunodeficiency viruses. However, the induction by active vaccination of antibodies that can potently neutralize a broad range of circulating virus strains is a goal not yet achieved, despite more than 2 decades of research. Here we review progress made in the field, from early empirical studies to today’s rational structure-based vaccine antigen design. We discuss the existence of broadly neutralizing antibodies, their implications for epitope discovery and recent progress made in antigen design. Finally, we consider the relationship between antigenicity and immunogenicity for B cell recognition and antibody production, a major hurdle for rational vaccine design to overcome. PMID:23227445

IgY Technology: Extraction of Chicken Antibodies from Egg Yolk by Polyethylene Glycol (PEG) Precipitation

PubMed Central

Pauly, Diana; Chacana, Pablo A.; Calzado, Esteban G.; Brembs, Björn; Schade, Rüdiger

2011-01-01

Hens can be immunized by means of i.m. vaccination (Musculus pectoralis, left and right, injection volume 0.5-1.0 ml) or by means of Gene-Gun plasmid-immunization. Dependent on the immunogenicity of the antigen, high antibody-titres (up to 1:100,000 - 1:1,000,000) can be achieved after only one or 3 - 4 boost immunizations. Normally, a hen lays eggs continuously for about 72 weeks, thereafter the laying capacity decreases. This protocol describes the extraction of total IgY from egg yolk by means of a precipitation procedure (PEG. Polson et al. 1980). The method involves two important steps. The first one is the removal of lipids and the second is the precipitation of total IgY from the supernatant of step one. After dialysis against a buffer (normally PBS) the IgY-extract can be stored at -20°C for more than a year. The purity of the extract is around 80 %, the total IgY per egg varies from 40-80 mg, dependent on the age of the laying hen. The total IgY content increases with the age of the hen from around 40 mg/egg up to 80 mg/egg (concerning PEG precipitation). The laying capacity of a hen per year is around 325 eggs. That means a total potential harvest of 20 g total IgY/year based on a mean IgY content of 60 mg total IgY/egg (see Table 1). PMID:21559009

Vaccine efficacy of live-attenuated virus, whole inactivated virus and alphavirus vectored subunit vaccines against antigenically distinct H3N2 swine influenza A viruses

USDA-ARS?s Scientific Manuscript database

Introduction Influenza A virus (IAV) is an important pathogen in swine, and the main intervention strategy is vaccination to induce neutralizing antibodies against the hemagglutinin (HA). Three major antigenic clusters, cyan, red, and green, were identified among H3N2 viruses circulating in pigs in ...

Induction of cancer testis antigen expression in circulating acute myeloid leukemia blasts following hypomethylating agent monotherapy

PubMed Central

Srivastava, Pragya; Paluch, Benjamin E.; Matsuzaki, Junko; James, Smitha R.; Collamat-Lai, Golda; Blagitko-Dorfs, Nadja; Ford, Laurie Ann; Naqash, Rafeh; Lübbert, Michael; Karpf, Adam R.; Nemeth, Michael J.; Griffiths, Elizabeth A.

2016-01-01

Cancer testis antigens (CTAs) are promising cancer associated antigens in solid tumors, but in acute myeloid leukemia, dense promoter methylation silences their expression. Leukemia cell lines exposed to HMAs induce expression of CTAs. We hypothesized that AML patients treated with standard of care decitabine (20mg/m2 per day for 10 days) would demonstrate induced expression of CTAs. Peripheral blood blasts serially isolated from AML patients treated with decitabine were evaluated for CTA gene expression and demethylation. Induction of NY-ESO-1 and MAGEA3/A6, were observed following decitabine. Re-expression of NY-ESO-1 and MAGEA3/A6 was associated with both promoter specific and global (LINE-1) hypomethylation. NY-ESO-1 and MAGEA3/A6 mRNA levels were increased irrespective of clinical response, suggesting that these antigens might be applicable even in patients who are not responsive to HMA therapy. Circulating blasts harvested after decitabine demonstrate induced NY-ESO-1 expression sufficient to activate NY-ESO-1 specific CD8+ T-cells. Induction of CTA expression sufficient for recognition by T-cells occurs in AML patients receiving decitabine. Vaccination against NY-ESO-1 in this patient population is feasible. PMID:26883197

Antigenic analysis of genetic variants of Canine distemper virus.

PubMed

Anis, Eman; Holford, Amy L; Galyon, Gina D; Wilkes, Rebecca P

2018-06-01

Canine distemper virus (CDV) is an RNA virus of the genus Morbillivirus within the family Paramyxoviridae. CDV produces multi-systemic disease in dogs and other terrestrial carnivores. With the development of modified live vaccines in the 1950s and 1960s, the disease, with a few exceptions, has been successfully controlled. However, recently the cases of CDV in vaccinated dogs have been increasing throughout the world, including the United States. There are many reasons that can lead to vaccine failure, including antigenic differences between the vaccine strains and the currently circulating wild-type strains. Currently, there are at least three genetically different CDV lineages circulating in the US. Therefore, in this study, we evaluated various wild-type CDV and vaccine isolates to determine if the genetic differences observed among various strains result in significant antigenic differences based on changes to the neutralizing epitopes. The results of a cross-neutralization assay revealed that there are antigenic differences among the tested CDV wild-type isolates as well as between the tested isolates and the vaccine strains currently used in the US. Therefore, these results suggest the need to develop an updated CDV vaccine. Copyright © 2018 Elsevier B.V. All rights reserved.

Hemagglutinin-specific neutralization of subacute sclerosing panencephalitis viruses

PubMed Central

Muller, Claude P.; Russell, Stephen J.

2018-01-01

Subacute sclerosing panencephalitis (SSPE) is a progressive, lethal complication of measles caused by particular mutants of measles virus (MeV) that persist in the brain despite high levels of neutralizing antibodies. We addressed the hypothesis that antigenic drift is involved in the pathogenetic mechanism of SSPE by analyzing antigenic alterations in the MeV envelope hemagglutinin protein (MeV-H) found in patients with SSPE in relation to major circulating MeV genotypes. To this aim, we obtained cDNA for the MeV-H gene from tissue taken at brain autopsy from 3 deceased persons with SSPE who had short (3–4 months, SMa79), average (3.5 years, SMa84), and long (18 years, SMa94) disease courses. Recombinant MeVs with a substituted MeV-H gene were generated by a reverse genetic system. Virus neutralization assays with a panel of anti-MeV-H murine monoclonal antibodies (mAbs) or vaccine-immunized mouse anti-MeV-H polyclonal sera were performed to determine the antigenic relatedness. Functional and receptor-binding analysis of the SSPE MeV-H showed activity in a SLAM/nectin-4–dependent manner. Similar to our panel of wild-type viruses, our SSPE viruses showed an altered antigenic profile. Genotypes A, G3, and F (SSPE case SMa79) were the exception, with an intact antigenic structure. Genotypes D7 and F (SSPE SMa79) showed enhanced neutralization by mAbs targeting antigenic site IIa. Genotypes H1 and the recently reported D4.2 were the most antigenically altered genotypes. Epitope mapping of neutralizing mAbs BH015 and BH130 reveal a new antigenic site on MeV-H, which we designated Φ for its intermediate position between previously defined antigenic sites Ia and Ib. We conclude that SSPE-causing viruses show similar antigenic properties to currently circulating MeV genotypes. The absence of a direct correlation between antigenic changes and predisposition of a certain genotype to cause SSPE does not lend support to the proposed antigenic drift as a pathogenetic mechanism in SSPE. PMID:29466428

Hemagglutinin-specific neutralization of subacute sclerosing panencephalitis viruses.

PubMed

Muñoz-Alía, Miguel Ángel; Muller, Claude P; Russell, Stephen J

2018-01-01

Subacute sclerosing panencephalitis (SSPE) is a progressive, lethal complication of measles caused by particular mutants of measles virus (MeV) that persist in the brain despite high levels of neutralizing antibodies. We addressed the hypothesis that antigenic drift is involved in the pathogenetic mechanism of SSPE by analyzing antigenic alterations in the MeV envelope hemagglutinin protein (MeV-H) found in patients with SSPE in relation to major circulating MeV genotypes. To this aim, we obtained cDNA for the MeV-H gene from tissue taken at brain autopsy from 3 deceased persons with SSPE who had short (3-4 months, SMa79), average (3.5 years, SMa84), and long (18 years, SMa94) disease courses. Recombinant MeVs with a substituted MeV-H gene were generated by a reverse genetic system. Virus neutralization assays with a panel of anti-MeV-H murine monoclonal antibodies (mAbs) or vaccine-immunized mouse anti-MeV-H polyclonal sera were performed to determine the antigenic relatedness. Functional and receptor-binding analysis of the SSPE MeV-H showed activity in a SLAM/nectin-4-dependent manner. Similar to our panel of wild-type viruses, our SSPE viruses showed an altered antigenic profile. Genotypes A, G3, and F (SSPE case SMa79) were the exception, with an intact antigenic structure. Genotypes D7 and F (SSPE SMa79) showed enhanced neutralization by mAbs targeting antigenic site IIa. Genotypes H1 and the recently reported D4.2 were the most antigenically altered genotypes. Epitope mapping of neutralizing mAbs BH015 and BH130 reveal a new antigenic site on MeV-H, which we designated Φ for its intermediate position between previously defined antigenic sites Ia and Ib. We conclude that SSPE-causing viruses show similar antigenic properties to currently circulating MeV genotypes. The absence of a direct correlation between antigenic changes and predisposition of a certain genotype to cause SSPE does not lend support to the proposed antigenic drift as a pathogenetic mechanism in SSPE.

Quantification of antibody (IgY) titers in hen eggs following immunization and their use in detecting cell surface molecules on nitrocellulose membranes.

PubMed

Ruan, Guang-Ping; Ma, Li; Meng, Xiao-Jing; Meng, Min-Jie; Wang, Xiao-Ning; Lin, Ying; Wu, Zheng-Qiang; He, Xiao-Wei; Wang, Ju-Fang; Zhu, Yong

2007-01-01

HLA-A*0201 alpha chain and beta2m were expressed from a prokaryotic system, and after refolding and purification, the alpha chain and beta2m were used to immunize eight laying hens. The titer of egg yolk antibody against alpha chain increased from 10(2) to 10(5.3) The titer of egg yolk antibody against beta2m increased from 10(1) to 10(4.7). The extent of titer increase is similar between the two antigens. An average of 135 mg purified polyclonal antibody (IgY) can be easily obtained from one egg yolk. The use of egg collection rather than serum collection is compatible with modern animal protection regulations. An average of 28 eggs were obtained from a laying hen every month, with a total amount of 3780 mg immunoglobulin extracted from one immunized hen every month, which would be equivalent to 630 mL of serum or 1260 mL of blood per month. Chickens are an optimal host for the production of polyclonal antibodies with high titer and high yield. Purified IgY was labeled with horseradish peroxidase and reacted with PBMC on nitrocellulose membranes indicating that the antibody can bind to the native conformation of class I HLA molecule on PBMC.

Avian influenza pandemic preparedness: developing prepandemic and pandemic vaccines against a moving target

PubMed Central

Singh, Neetu; Pandey, Aseem; Mittal, Suresh K.

2010-01-01

The unprecedented global spread of highly pathogenic avian H5N1 influenza viruses within the past ten years and their extreme lethality to poultry and humans has underscored their potential to cause an influenza pandemic. Combating the threat of an impending H5N1 influenza pandemic will require a combination of pharmaceutical and nonpharmaceutical intervention strategies. The emergence of the H1N1 pandemic in 2009 emphasised the unpredictable nature of a pandemic influenza. Undoubtedly, vaccines offer the most viable means to combat a pandemic threat. Current egg-based influenza vaccine manufacturing strategies are unlikely to be able to cater to the huge, rapid global demand because of the anticipated scarcity of embryonated eggs in an avian influenza pandemic and other factors associated with the vaccine production process. Therefore, alternative, egg-independent vaccine manufacturing strategies should be evaluated to supplement the traditional egg-derived influenza vaccine manufacturing. Furthermore, evaluation of dose-sparing strategies that offer protection with a reduced antigen dose will be critical for pandemic influenza preparedness. Development of new antiviral therapeutics and other, nonpharmaceutical intervention strategies will further supplement pandemic preparedness. This review highlights the current status of egg-dependent and egg-independent strategies against an avian influenza pandemic. PMID:20426889

Effect of microgravity on primordial germ cells (PGCs) in silk chicken offspring ( Gallus gallus domesticus)

NASA Astrophysics Data System (ADS)

Zhou, Zhenming; Li, Zandong

2011-08-01

Primordial germ cells (PGCs), precursors of germline cells, display a variety of antigens during their migration to target gonads. Here, we used silk chicken offspring ( Gallus gallus domesticus) embryos subjected to space microgravity to investigate the influence of microgravity on PGCs. The ShenZhou-3 unmanned spaceship carried nine fertilized silk chicken eggs, named the flight group, returned to Earth after 7 days space flight. And the control group has the same clan with the flight group. PGCs from flight and control group silk chicken offspring embryos were examined during migration by using two antibodies (2C9 and anti-SSEA-1), in combination with the horseradish peroxidase detection system, and using periodic acid-Schiff's solution (PAS) reaction. After incubation for about 30 h, SSEA-1 and 2C9 positive cells were detected in the germinal crescent of flight and control group silk chicken offspring embryos. After incubation of eggs for 2-2.5 days, SSEA-1 and 2C9 positive cells were detected in embryonic blood vessels of flight and control group silk chicken offspring embryos. After incubation of eggs for 5.5 days, PGCs in the dorsal mesentery and gonad could also be identified in flight and control group silk chicken offspring embryos by using SSEA-1 and 2C9 antibodies. Based on location and PAS staining, these cells were identified as PGCs. Meanwhile, at the stage of PGCs migration and then becoming established in the germinal ridges, no difference in SSEA-1 or 2C9 staining was detected between female and male PGCs in flight and control group silk chicken offspring embryos. Although there were differences in the profiles of PGC concentration between male and female embryos during the special circulating stage, changing profile of PGCs concentration was similar in same sex between flight and control group offspring embryos. We concluded that there is little effect on PGCs in offspring embryos of microgravity-treated chicken and that PGC development appears to be normal.

Vaccination of lambs against Taenia ovis infection using antigens collected during in vitro cultivation of larvae: passive protection via colostrum from vaccinated ewes and the duration of immunity from a single vaccination.

PubMed

Rickard, M D; Boddington, E B; McQuade, N

1977-11-01

Fifty Merino-cross ewes were vaccinated approximately four weeks before parturition with antigens collected during in vitro cultivation of Taenia ovis larvae. A further 50 pregnant ewes were sham-vaccinated at the same time. When the first 20 lambs from each group of ewes were one to two weeks old they were placed, with the ewes, on an experimental paddock heavily contaminated with T ovis eggs. After six weeks the lambs were killed and their total carcase musculature and hearts examined for cysticerci. The results showed that the ewes vaccinated in late pregnancy had conferred a very high degree of transcolostral immunity upon their lambs against the T ovis challenge infection. Eighty T ovis-free Merino-cross weaner lambs, four months old, were divided into two groups of 40. One group was vaccinated with T ovis culture antigens and the other group was sham-vaccinated. At intervals of one, four, eight and 12 months after vaccination 10 lambs from each group were allowed to graze on the plot contaminated with T ovis eggs. After six weeks the lambs were killed and examined for cysticerci of T ovis. The results indicated that the single vaccination had stimulated a high level of immunity which persisted for at least 12 months.

[Prokaryotic expression and histological localization of the Taenia solium CDC37 gene].

PubMed

Huang, Jiang; Li, Bo; Dai, Jia-Lin; Zhang, Ai-Hua

2013-02-01

To express Taenia solium gene encoding cell division cycle 37 protein (TsCDC37) and investigate its antigenicity and localization in adults of Taenia solium. The complete coding sequence of TsCDC37 was amplified by PCR based on the recombinant plasmid clone from the cDNA library of adult Taenia solium. The PCR product was cloned into a prokaryotic expression vector pET-28a (+). The recombinant expression plasmid was identified by PCR, double endonuclease digestion and sequencing. The recombinant plasmid was transformed into E. coli BL21/DE3 and followed by expression of the protein induced by IPTG. The mice were immunized subcutaneously with purified recombinant TsCDC37 formulated in Freund's adjuvant. The antigenicity of the recombinant protein was examined by Western blotting. The localization of TsCDC37 in adult worms was demonstrated by immunofluorescent technique. The recombinant expression vector was constructed successfully. The recombinant protein was about M(r) 52 000, it was then purified and specifically recognized by immuno sera of SD rats and sera from patients infected with Taenia solium, Taenia saginata or Taenia asiatica. The immunofluorescence assay revealed that TsCDC37 located at the tegument of T. solium adult and the eggs. TsCDC37 gene has been expressed with immunoreactivity. The recombinant protein is mainly expressed in tegument and egg, and is a common antigen of the three human taenia cestodes.

[Molecular characterization of human influenza viruses--a look back on the last 10 years].

PubMed

Schweiger, Brunhilde

2006-01-01

Influenza A (H3N2) viruses and influenza B viruses have caused more than 90% of influenza infections in Germany during the last then years. Continuous and extensive antigenic variation was evident for both the hemagglutinin (HA) and neuraminidase (NA) surface proteins of H3N2 and influenza B viruses. Molecular characterisation revealed an ongoing genetic drift even in years when the antigenic profiles of circulating strains were indistinguishable from those of the previous season. Retrospective phylogenetic studies showed that viruses similar to vaccine strains circulated one or two years before a given strain was recommended as vaccine strain. New drift variants of H3N2 viruses with significantly changed antigenic features appeared during the seasons 1997/1998 and 2002/2003. Most influenza seasons were characterised by a co-circulation of at least two different lineages of H3N2 viruses. Genetic reassortment between H3N2 viruses belonging to separate lineages caused the different evolutionary pathways of the HA and viruses was responsible for the occurrence of H1N2 viruses during the season 2001/02. This new subtype has been detected only sporadically in Germany. The evolution of influenza B viruses was characterised by the re-emergence of B/Victoria/2/87-lineage viruses and their co-circulation with viruses of the B/Yamagata/16/88-lineage. Reassortant B viruses possessing a Victoria/87-lineage HA and a Yamagata/88-like NA were predominant in Germany during 2002/03 and 2004/05.

Activation of maternal centrosomes in unfertilized sea urchin eggs

NASA Technical Reports Server (NTRS)

Schatten, H.; Walter, M.; Biessmann, H.; Schatten, G.

1992-01-01

Centrosomes are undetectable in unfertilized sea urchin eggs, and normally the sperm introduces the cell's microtubule-organizing center (MTOC) at fertilization. However, artificial activation or parthenogenesis triggers microtubule assembly in the unfertilized egg, and this study explores the reappearance and behavior of the maternal centrosome. During activation with A23187 or ammonia, microtubules appear first at the cortex; centrosomal antigen is detected diffusely throughout the entire cytoplasm. Later, the centrosome becomes more distinct and organizes a radial microtubule shell, and eventually a compact centrosome at the egg center organizes a monaster. In these activated eggs, centrosomes undergo cycles of compaction and decompaction in synchrony with the chromatin, which also undergoes cycles of condensation and decondensation. Parthenogenetic activation with heavy water (50% D2O) or the microtubule-stabilizing drug taxol (10 microM) induces numerous centrosomal foci in the unfertilized sea urchin egg. Within 15 min after incubation in D2O, numerous fine centrosomal foci are detected, and they organize a connected network of numerous asters which fill the entire egg. Taxol induces over 100 centrosomal foci by 15 min after treatment, which organize a corresponding number of asters. The centrosomal material in either D2O- or taxol-treated eggs aggregates with time to form fewer but denser foci, resulting in fewer and larger asters. Fertilization of eggs pretreated with either D2O or taxol shows that the paternal centrosome is dominant over the maternal centrosome. The centrosomal material gradually becomes associated with the enlarged sperm aster. These experiments demonstrate that maternal centrosomal material is present in the unfertilized egg, likely as dispersed undetectable material, which can be activated without paternal contributions. At fertilization, paternal centrosomes become dominant over the maternal centrosomal material.

Antigenic and genetic evolution of contemporary swine H1 influenza viruses in the United States.

PubMed

Rajao, Daniela S; Anderson, Tavis K; Kitikoon, Pravina; Stratton, Jered; Lewis, Nicola S; Vincent, Amy L

2018-05-01

Several lineages of influenza A viruses (IAV) currently circulate in North American pigs. Genetic diversity is further increased by transmission of IAV between swine and humans and subsequent evolution. Here, we characterized the genetic and antigenic evolution of contemporary swine H1N1 and H1N2 viruses representing clusters H1-α (1A.1), H1-β (1A.2), H1pdm (1A.3.3.2), H1-γ (1A.3.3.3), H1-δ1 (1B.2.2), and H1-δ2 (1B.2.1) currently circulating in pigs in the United States. The δ1-viruses diversified into two new genetic clades, H1-δ1a (1B.2.2.1) and H1-δ1b (1B.2.2.2), which were also antigenically distinct from the earlier H1-δ1-viruses. Further characterization revealed that a few key amino acid changes were associated with antigenic divergence in these groups. The continued genetic and antigenic evolution of contemporary H1 viruses might lead to loss of vaccine cross-protection that could lead to significant economic impact to the swine industry, and represents a challenge to public health initiatives that attempt to minimize swine-to-human IAV transmission. Published by Elsevier Inc.

Evaluation of the sensitivity of IgG and IgM ELISA in detecting Schistosoma mansoni infections in a low endemicity setting.

PubMed

Espirito-Santo, M C C; Sanchez, M C A; Sanchez, A R; Alvarado-Mora, M V; Castilho, V L P; Gonçalves, E M N; Luna, E J A; Gryschek, R C B

2014-12-01

Schistosomiasis is a major public health concern, with 200 million people infected worldwide. In Brazil, this disease has been reported in 19 states, and its prevalence in the city of Barra Mansa in Rio de Janeiro State is 1 %. The parasitological diagnostic methods currently available in these areas lack sensitivity; however, enzyme-linked immunosorbent assays (ELISAs) have been employed successfully for the diagnosis of schistosomiasis by using antibodies against antigens of Schistosoma mansoni adult worms and eggs, and for the detection of circulating antigens. The objective of this study was to determine systematically the prevalence of S. mansoni infection in the peripheral areas of Barra Mansa. A cross-sectional study was conducted from April to December 2011 by using probabilistic sampling that collected 610 fecal samples and 612 serum samples. ELISA-IgG with total extracts and ELISA-IgM with trichloroacetic acid-soluble fractions were employed to detect antibodies against S. mansoni and were compared with the Kato-Katz and Hoffman parasitological techniques. Among the individuals studied, anti-S. mansoni antibodies were detected in 11.16 % (n = 71) by ELISA-IgG and in 20.75 % (n = 132) by ELISA-IgM, while the parasitological techniques showed 0.82 % (n = 5) positivity. The agreement between the two ELISA tests was 85.38 % (n = 543), and 8.65 % (n = 55) of the serum samples showed positive results in both tests. The higher positivity of the ELISA-IgM test corroborates the results of previous reports and indicates that the test may be a useful tool in epidemiological studies, particularly in areas of low endemicity for S. mansoni.

Laboratory Surveillance of Rabies in Humans, Domestic Animals, and Bats in Madagascar from 2005 to 2010

PubMed Central

Reynes, Jean-Marc; Andriamandimby, Soa Fy; Razafitrimo, Girard Marcelin; Razainirina, Josette; Jeanmaire, Elisabeth Marie; Bourhy, Hervé; Heraud, Jean-Michel

2011-01-01

Background. Rabies virus (RABV) has circulated in Madagascar at least since the 19th century. Objectives. To assess the circulation of lyssavirus in the island from 2005 to 2010. Materials and Methods. Animal (including bats) and human samples were tested for RABV and other lyssavirus using antigen, ribonucleic acid (RNA), and antibodies detection and virus isolation. Results. Half of the 437 domestic or tame wild terrestrial mammal brains tested were found RABV antigen positive, including 54% of the 341 dogs tested. This percentage ranged from 26% to 75% across the period. Nine of the 10 suspected human cases tested were laboratory confirmed. RABV circulation was confirmed in 34 of the 38 districts sampled. No lyssavirus RNA was detected in 1983 bats specimens. Nevertheless, antibodies against Lagos bat virus were detected in the sera of 12 among 50 Eidolon dupreanum specimens sampled. Conclusion. More than a century after the introduction of the vaccine, rabies still remains endemic in Madagascar. PMID:21991442

Molecular Epidemiology of Influenza A/H3N2 Viruses Circulating in Mexico from 2003 to 2012

PubMed Central

Escalera-Zamudio, Marina; Nelson, Martha I.; Cobián Güemes, Ana Georgina; López-Martínez, Irma; Cruz-Ortiz, Natividad; Iguala-Vidales, Miguel; García, Elvia Rodríguez; Barrera-Badillo, Gisela; Díaz-Quiñonez, Jose Alberto; López, Susana; Arias, Carlos F.; Isa, Pavel

2014-01-01

In this work, nineteen influenza A/H3N2 viruses isolated in Mexico between 2003 and 2012 were studied. Our findings show that different human A/H3N2 viral lineages co-circulate within a same season and can also persist locally in between different influenza seasons, increasing the chance for genetic reassortment events. A novel minor cluster was also identified, named here as Korea, that circulated worldwide during 2003. Frequently, phylogenetic characterization did not correlate with the determined antigenic identity, supporting the need for the use of molecular evolutionary tools additionally to antigenic data for the surveillance and characterization of viral diversity during each flu season. This work represents the first long-term molecular epidemiology study of influenza A/H3N2 viruses in Mexico based on the complete genomic sequences and contributes to the monitoring of evolutionary trends of A/H3N2 influenza viruses within North and Central America. PMID:25075517

TGF-Beta Gene Polymorphisms in Food Allergic versus Non-Food Allergic Eosinophilic Esophagitis

DTIC Science & Technology

2013-10-01

our EE subjects are male, Caucasian, and have another atopic disorder (asthma, allergy, eczema and/or food allergy) (n=142, analysis is ongoing...Rhinitis (%) Eczema (%) 43% 66% 30% Table 3: Food IgE Sensitization Pattern Food Antigen IgE Positive (% patients, 95% CI) (n=122-129) Egg 39

Amblyomma imitator Ticks as Vectors of Rickettsia rickettsii, Mexico

PubMed Central

Oliveira, Karla A.; Pinter, Adriano; Medina-Sanchez, Aaron; Boppana, Venkata D.; Wikel, Stephen K.; Saito, Tais B.; Shelite, Thomas; Blanton, Lucas; Popov, Vsevolod; Teel, Pete D.; Walker, David H.; Galvao, Marcio A.M.; Mafra, Claudio

2010-01-01

Real-time PCR of Amblyomma imitator tick egg masses obtained in Nuevo Leon State, Mexico, identified a Rickettsia species. Sequence analyses of 17-kD common antigen and outer membrane protein A and B gene fragments showed to it to be R. rickettsii, which suggested a potential new vector for this bacterium. PMID:20678325

Hot spot computational identification: Application to the complex formed between the hen egg white lysozyme (HEL) and the antibody HyHEL-10

NASA Astrophysics Data System (ADS)

Moreira, I. S.; Fernandes, P. A.; Ramos, M. J.

The definition and comprehension of the hot spots in an interface is a subject of primary interest for a variety of fields, including structure-based drug design. Therefore, to achieve an alanine mutagenesis computational approach that is at the same time accurate and predictive, capable of reproducing the experimental mutagenesis values is a major challenge in the computational biochemistry field. Antibody/protein antigen complexes provide one of the greatest models to study protein-protein recognition process because they have three fundamentally features: specificity, high complementary association and a small epitope restricted to the diminutive complementary determining regions (CDR) region, while the remainder of the antibody is largely invariant. Thus, we apply a computational mutational methodological approach to the study of the antigen-antibody complex formed between the hen egg white lysozyme (HEL) and the antibody HyHEL-10. A critical evaluation that focuses essentially on the limitations and advantages between different computational methods for hot spot determination, as well as between experimental and computational methodological approaches, is presented.

Immune complex orchitis in vasectomized rabbits

PubMed Central

1976-01-01

The results of the present study show that bilaterally vasectomized rabbits with high levels of antibodies to sperm antigens frequently develop an orchitis associated with granular deposits of rabbit IgG and C3 in the basement membranes of seminiferous tubules. The immune deposits correspond in location to electron-opaque deposits seen by electron microscopy. The "membranous orchitis" is characterized by thickening of tubular basement membranes, acc-mulation of macrophages and a few polymorphonuclear leukocytes, and destruction of the basal lamina, of the Sertoli and spermatogenetic cells. The pathogenetic role of the immune deposits and the possibility that they contain antigen- antibody complexes is indicated by: (a) selective accumulation of IgG and C3 granular deposits along the basement membranes of seminiferous tubules in rabbits producing high and persistent levels of antibodies to sperm antigens; (b) the elution of immunoglobulins from tissues with chaotropic ion-containing buffers, acid buffers, or heat; (c) the observation that the immuno-globulins accumulated in the testis contain antibody to sperm antigens; and (d) the demonstration of sperm antigens in a location similar to that of IgG and C3. It is postulated that sperm antigen-antibody complexes are formed in the basement membranes of seminiferous tubules when antigens leaking out of the tubules react with specific antibody coming from the circulation. In two rabbits with higher levels of circulating antisperm antibodies and severe orchitis, granular deposits of IgG and C3 were also present in renal glomeruli. Immunoglobulins eluted from the kidneys contained antibody with antisperm activity. These findings are consistent with the hypothesis that in some vasectomized rabbits extratesticular lesions may develop by a mechanism comparable to that of chronic serum sickness. PMID:129498

Naturally occurring tolerance acquisition to foods in previously allergic children is characterized by antigen specificity and associated with increased subsets of regulatory T cells.

PubMed

Qamar, N; Fishbein, A B; Erickson, K A; Cai, M; Szychlinski, C; Bryce, P J; Schleimer, R P; Fuleihan, R L; Singh, A M

2015-11-01

Food allergy affects approximately 6-8% of children, and increasing in prevalence. Some children naturally outgrow their food allergy without intervention, but the mechanisms by which this occurs remain poorly understood. We sought to investigate the role of regulatory T cells in the development of naturally acquired tolerance. Fifty-eight children (1-18 years) with either egg or peanut allergy, recent acquisition of natural tolerance to egg or peanut, or no food allergy were studied. Peripheral blood mononuclear cells (PBMC) from these groups were stimulated with relevant antigen for 48 h and flow cytometry performed to characterize both surface (CD3, CD4, CD25, CD14, CD19, and CD127) and intracellular markers (IL-10, Foxp3, and IL-5). Resting PBMC from naturally tolerant patients had significantly increased CD3+CD4+CD25+CD127loFoxp3+ cells, when compared to allergic or control patients (mean 6.36 vs. 2.37 vs. 2.62%, respectively, P < 0.05). Upon stimulation with relevant antigen, naturally tolerant patients also had increased IL-10-expressing CD25+CD127lo cells (6.33 vs. 1.65 vs. 0.7, P < 0.01), Foxp3+ cells (mean 12.6 vs. 5.42 vs. 3%, P < 0.01), and CD4+ cells (mean 4.48 vs. 1.59 vs. 0.87%, P < 0.01); the increase was not observed in PBMCs from allergic or control patients. Additionally, this upregulation was only seen with relevant antigen stimulation and not upon stimulation with unrelated antigen. The increased CD3+CD4+CD25+CD127lo cells at baseline and upon stimulation and increased induction of IL-10-producing cells of several types, including Tr1 cells, from naturally tolerant patients suggests an important role for regulatory T cell subsets in the acquisition of natural tolerance. © 2015 John Wiley & Sons Ltd.

Naturally Occurring Tolerance Acquisition to Foods in Previously Allergic Children is Characterized by Antigen Specificity and Associated with Increased Subsets of Regulatory T cells

PubMed Central

Qamar, Nashmia; Fishbein, Anna B.; Erickson, Kristin A.; Cai, Miao; Szychlinski, Christine; Bryce, Paul J.; Schleimer, Robert P.; Fuleihan, Ramsay L.; Singh, Anne Marie

2015-01-01

Background Food allergy affects approximately 6–8% of children, and increasing in prevalence. Some children naturally outgrow their food allergy without intervention but the mechanisms by which this occurs remain poorly understood. We sought to investigate the role of regulatory T cells in the development of naturally acquired tolerance. Methods Fifty-eight children (1 to 18 years) with either egg or peanut allergy, recent acquisition of natural tolerance to egg or peanut, or no food allergy were studied. Peripheral blood mononuclear cells (PBMC) from these groups were stimulated with relevant antigen for 48 hours and flow cytometry performed to characterize both surface (CD3, CD4, CD25, CD14, CD19, CD127) and intracellular markers (IL-10, Foxp3, and IL-5). Results Resting PBMC from naturally tolerant patients had significantly increased CD3+CD4+CD25+CD127loFoxp3+ cells, when compared to allergic or control patients [mean 6.36 vs 2.37 vs 2.62%, respectively, p<0.05]. Upon stimulation with relevant antigen, naturally tolerant patients also had increased IL-10-expressing CD25+CD127lo cells [6.33 vs 1.65 vs 0.7, p<0.01], Foxp3+ cells [mean 12.6 vs 5.42 vs 3%, p<0.01] and CD4+ cells [mean 4.48 vs 1.59 vs 0.87%, p<0.01]; the increase was not observed in PBMCs from allergic or control patients. Additionally, this upregulation was only seen with relevant antigen stimulation and not upon stimulation with unrelated antigen. Conclusion The increased CD3+CD4+CD25+CD127lo cells at baseline and upon stimulation and increased induction of IL-10-producing cells of several types, including Tr1 cells, from naturally tolerant patients suggests an important role for regulatory T cell subsets in the acquisition of natural tolerance. PMID:25989379

Assessing humoral and cell-mediated immune response in Hawaiian green turtles, Chelonia mydas

USGS Publications Warehouse

Work, Thierry M.; Balazs, George H.; Rameyer, Robert; Chang, S.P.; Berestecky, J.

2000-01-01

Seven immature green turtles, Chelonia mydas, captured from Kaneohe Bay on the island of Oahu were used to evaluate methods for assessing their immune response. Two turtles each were immunized intramuscularly with egg white lysozyme (EWL) in Freund’s complete adjuvant, Gerbu, or ISA-70; a seventh turtle was immunized with saline only and served as a control. Humoral immune response was measured with an indirect enzyme linked immunosorbent assay (ELISA). Cell-mediated immune response was measured using in vitro cell proliferation assays (CPA) using whole blood or peripheral blood mononuclear cells (PBM) cultured with concanavalin A (ConA), phytohaemagglutinin (PHA), or soluble egg EWL antigen. All turtles, except for one immunized with Gerbu and the control, produced a detectable humoral immune response by 6 weeks which persisted for at least 14 weeks after a single immunization. All turtles produced an anamnestic humoral immune response after secondary immunization. Antigen specific cell-mediated immune response in PBM was seen in all turtles either after primary or secondary immunization, but it was not as consistent as humoral immune response; antigen specific cell-mediated immune response in whole blood was rarely seen. Mononuclear cells had significantly higher stimulation indices than whole blood regardless of adjuvant, however, results with whole blood had lower variability. Both Gerbu and ISA-70 appeared to potentiate the cell-mediated immune response when PBM or whole blood were cultured with PHA. This is the first time cell proliferation assays have been compared between whole blood and PBM for reptiles. This is also the first demonstration of antigen specific cell-mediated response in reptiles. Cell proliferation assays allowed us to evaluate the cell-mediated immune response of green turtles. However, CPA may be less reliable than ELISA for detecting antigen specific immune response. Either of the three adjuvants appears suitable to safely elicit a detectable immune response in green turtles.

The glycosphingolipid P₁ is an ovarian cancer-associated carbohydrate antigen involved in migration.

PubMed

Jacob, F; Anugraham, M; Pochechueva, T; Tse, B W C; Alam, S; Guertler, R; Bovin, N V; Fedier, A; Hacker, N F; Huflejt, M E; Packer, N; Heinzelmann-Schwarz, V A

2014-10-14

The level of plasma-derived naturally circulating anti-glycan antibodies (AGA) to P1 trisaccharide has previously been shown to significantly discriminate between ovarian cancer patients and healthy women. Here we aim to identify the Ig class that causes this discrimination, to identify on cancer cells the corresponding P1 antigen recognised by circulating anti-P1 antibodies and to shed light into the possible function of this glycosphingolipid. An independent Australian cohort was assessed for the presence of anti-P1 IgG and IgM class antibodies using suspension array. Monoclonal and human derived anti-glycan antibodies were verified using three independent glycan-based immunoassays and flow cytometry-based inhibition assay. The P1 antigen was detected by LC-MS/MS and flow cytometry. FACS-sorted cell lines were studied on the cellular migration by colorimetric assay and real-time measurement using xCELLigence system. Here we show in a second independent cohort (n=155) that the discrimination of cancer patients is mediated by the IgM class of anti-P1 antibodies (P=0.0002). The presence of corresponding antigen P1 and structurally related epitopes in fresh tissue specimens and cultured cancer cells is demonstrated. We further link the antibody and antigen (P1) by showing that human naturally circulating and affinity-purified anti-P1 IgM isolated from patients ascites can bind to naturally expressed P1 on the cell surface of ovarian cancer cells. Cell-sorted IGROV1 was used to obtain two study subpopulations (P1-high, 66.1%; and P1-low, 33.3%) and observed that cells expressing high P1-levels migrate significantly faster than those with low P1-levels. This is the first report showing that P1 antigen, known to be expressed on erythrocytes only, is also present on ovarian cancer cells. This suggests that P1 is a novel tumour-associated carbohydrate antigen recognised by the immune system in patients and may have a role in cell migration. The clinical value of our data may be both diagnostic and prognostic; patients with low anti-P1 IgM antibodies present with a more aggressive phenotype and earlier relapse.

Two SmDLC antigens as potential vaccines against schistosomiasis.

PubMed

Diniz, Patricia Placoná; Nakajima, Erika; Miyasato, Patricia Aoki; Nakano, Eliana; de Oliveira Rocha, Márcia; Martins, Elizabeth Angelica Leme

2014-12-01

The Schistosoma mansoni transcriptome revealed new members of the dynein light chain family (DLC/LC8). The antigenicity and immunogenicity of these proteins, and their potential as vaccine candidates were investigated. Two DLC genes (DLC12_JI392413.1 and DLC13_JI387686.1) were cloned and the recombinant proteins produced in E. coli. The immunization of mice with the rDLCs, using alhydrogel as adjuvant, resulted in high titers of antibodies, indicated that these proteins are highly immunogenic. The anti-DLCs antibodies presented cross reactivity with both recombinant antigens and also recognized proteins from S. mansoni adult worm extracts. The DLC12 and DLC13 immunized animals were challenged by infection with cercariae and a protective profile was observed in three different assays, with a significant decreased in worm burden, of 43% and 51% respectively, when compared to the non-vaccinated group. The granulomas formation due to egg retention in the hepatic tissues was evaluated 45 days after infection. Smaller granulomas were observed in the liver of DLC immunized animals, up to 70% reduction in comparison to the granulomas size in the non-vaccinated animals. Fifty-five days after infection, the average size of the hepatic granulomas was still 25-35% smaller in the DLCs vaccinated groups. The interference of DLC immunization on the hepatic granuloma formation may reflect the lower worm burden and consequent decrease on the number of eggs retained in the liver, resulting in lower pro-inflammatory level in the tissue. The protective effect of DLCs immunization, decreasing the worm burden and delaying the rate of granuloma formation, suggests that these antigens should be further studied as potential vaccine candidates. Copyright © 2014 Elsevier B.V. All rights reserved.

Phylogeny of Immune Recognition: Processing and Presentation of Structurally Defined Proteins in Channel Catfish Immune Responses

PubMed Central

Vallejo, Abbe N.; Miller, Norman W.

1991-01-01

This work was undertaken to investigate whether or not antigen processing and presentation are important in channel catfish in vitro secondary immune responses elicited with structurally defined proteins, namely, pigeon heart cytochrome C (pCytC), hen egg lysozyme, and horse myoglobin. The use of in vitro antigen-pulsed and fixed B cells or monocytes as antigen presenting cells (APC) resulted in autologous peripheral blood leukocytes (PBL) responding with vigorous proliferation and antibody production in vitro. In addition, several long-term catfish monocyte lines have been found to function as efficient APC with autologous but not allogeneic responders. Subsequent separation of the responding PBL into sIg- (T-cell-enriched) and B (sIg+) cell subsets showed that both underwent proliferative responses to antigen-pulsed and fixed APC. Moreover, allogeneic cells used as APC were found to induce only strong mixed leukocyte reactions without specific in vitro antibody production. Initial attempts at identifying the immunogenic region(s) of the protein antigens for catfish indicated there are two such regions for pCytC, namely, peptides 66-80 and 81-104. PMID:1668258

Membranous Nephropathy and Anti-Podocytes Antibodies: Implications for the Diagnostic Workup and Disease Management.

PubMed

Pozdzik, Agnieszka; Brochériou, Isabelle; David, Cristina; Touzani, Fahd; Goujon, Jean Michel; Wissing, Karl Martin

2018-01-01

The discovery of circulating antibodies specific for native podocyte antigens has transformed the diagnostic workup and greatly improved management of idiopathic membranous nephropathy (iMN). In addition, their identification has clearly characterized iMN as a largely autoimmune disorder. Anti-PLA2R1 antibodies are detected in approximately 70% to 80% and anti-THSD7A antibodies in only 2% of adult patients with iMN. The presence of anti-THSD7A antibodies is associated with increased risk of malignancy. The assessment of PLA2R1 and THSD7A antigen expression in glomerular immune deposits has a better sensitivity than measurement of the corresponding autoantibodies. Therefore, in the presence of circulating anti-podocytes autoantibodies and/or enhanced expression of PLA2R1 and THSD7A antigens MN should be considered as primary MN (pMN). Anti-PLA2R1 or anti-THSD7A autoantibodies have been proposed as biomarkers of autoimmune disease activity and their blood levels should be regularly monitored in pMN to evaluate disease activity and predict outcomes. We propose a revised clinical workup flow for patients with MN that recommends assessment of kidney biopsy for PLA2R1 and THSD7A antigen expression, screening for circulating anti-podocytes antibodies, and assessment for secondary causes, especially cancer, in patients with THSD7A antibodies. Persistence of anti-podocyte antibodies for 6 months or their increase in association with nephrotic proteinuria should lead to the introduction of immunosuppressive therapies. Recent data have reported the efficacy and safety of new specific therapies targeting B cells (anti-CD20 antibodies, inhibitors of proteasome) in pMN which should lead to an update of currently outdated treatment guidelines.

Membranous Nephropathy and Anti-Podocytes Antibodies: Implications for the Diagnostic Workup and Disease Management

PubMed Central

Brochériou, Isabelle; David, Cristina; Touzani, Fahd; Goujon, Jean Michel; Wissing, Karl Martin

2018-01-01

The discovery of circulating antibodies specific for native podocyte antigens has transformed the diagnostic workup and greatly improved management of idiopathic membranous nephropathy (iMN). In addition, their identification has clearly characterized iMN as a largely autoimmune disorder. Anti-PLA2R1 antibodies are detected in approximately 70% to 80% and anti-THSD7A antibodies in only 2% of adult patients with iMN. The presence of anti-THSD7A antibodies is associated with increased risk of malignancy. The assessment of PLA2R1 and THSD7A antigen expression in glomerular immune deposits has a better sensitivity than measurement of the corresponding autoantibodies. Therefore, in the presence of circulating anti-podocytes autoantibodies and/or enhanced expression of PLA2R1 and THSD7A antigens MN should be considered as primary MN (pMN). Anti-PLA2R1 or anti-THSD7A autoantibodies have been proposed as biomarkers of autoimmune disease activity and their blood levels should be regularly monitored in pMN to evaluate disease activity and predict outcomes. We propose a revised clinical workup flow for patients with MN that recommends assessment of kidney biopsy for PLA2R1 and THSD7A antigen expression, screening for circulating anti-podocytes antibodies, and assessment for secondary causes, especially cancer, in patients with THSD7A antibodies. Persistence of anti-podocyte antibodies for 6 months or their increase in association with nephrotic proteinuria should lead to the introduction of immunosuppressive therapies. Recent data have reported the efficacy and safety of new specific therapies targeting B cells (anti-CD20 antibodies, inhibitors of proteasome) in pMN which should lead to an update of currently outdated treatment guidelines. PMID:29511687

7 CFR 58.422 - Brine tank.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AGRICULTURAL MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT (CONTINUED) GRADING AND INSPECTION, GENERAL SPECIFICATIONS FOR APPROVED PLANTS AND STANDARDS FOR GRADES OF DAIRY PRODUCTS 1 General... clean, well circulated, and of the proper strength and temperature for the variety of cheese being made. ...

Quail egg homogenate alleviates food allergy induced eosinophilic esophagitis like disease through modulating PAR-2 transduction pathway in peanut sensitized mice.

PubMed

Lianto, Priscilia; Han, Shiwen; Li, Xinrui; Ogutu, Fredrick Onyango; Zhang, Yani; Fan, Zhuoyan; Che, Huilian

2018-01-18

The present pharmacotherapy for eosinophilic esophagitis (EoE) fundamentally depend on inhaled corticosteroids. Despite the fact that oral intake of topical steroids can be successful in restricting EoE-related inflammation, there are concerns with respect to the long term utilization of steroids, especially in kids. In the current research, we assess the effect of quail egg, which is reportedly a known serine protease inhibitor, on symptomatology and immune responses in a peanut-sensitized mouse model of food allergy induced EoE. Daily oral treatment with quail egg attenuated mice symptomatology and immune response. Treatment with quail egg inhibited antigen-prompted increments in mouse tryptase and eosinophil cationic protein (ECP) in serum and eosinophil in inflamed tissues like oesophagus, lung, and digestive system. Quail egg treatment resulted in decreased antibody specific IgE and IgG1 and a variety of inflammatory genes that were abnormally expressed in EoE. Other effects included increased IL-10, decreased PAR-2 activation and NF-kB p65 in inflamed tissues. Our results suggest that quail egg treatment may have therapeutic potential in attenuating the symptoms of food allergy induced EoE like disease through regulating PAR-2 downstream pathway by blocking the activation of the transcription factor NF-kB p65 activity.

Intermittent IL-7 Signaling Essential for T cell Homeostasis | Center for Cancer Research

Cancer.gov

In order for the immune system to mount an appropriate response to foreign antigens throughout a person’s life, the body must maintain a sufficient population of circulating mature, naïve T cells, a process known as T cell homeostasis. Previous studies revealed that this process depends upon signaling from the cytokine interleukin-7 (IL-7) as well as from the T cell antigen

Genetic and antigenic characterisation of serotype A FMD viruses from East Africa to select new vaccine strains

PubMed Central

Bari, Fufa D.; Parida, Satya; Tekleghiorghis, Tesfaalem; Dekker, Aldo; Sangula, Abraham; Reeve, Richard; Haydon, Daniel T.; Paton, David J.; Mahapatra, Mana

2014-01-01

Vaccine strain selection for emerging foot-and-mouth disease virus (FMDV) outbreaks in enzootic countries can be addressed through antigenic and genetic characterisation of recently circulating viruses. A total of 56 serotype A FMDVs isolated between 1998 and 2012, from Central, East and North African countries were characterised antigenically by virus neutralisation test using antisera to three existing and four candidate vaccine strains and, genetically by characterising the full capsid sequence data. A Bayesian analysis of the capsid sequence data revealed the viruses to be of either African or Asian topotypes with subdivision of the African topotype viruses into four genotypes (Genotypes I, II, IV and VII). The existing vaccine strains were found to be least cross-reactive (good matches observed for only 5.4–46.4% of the sampled viruses). Three bovine antisera, raised against A-EA-2007, A-EA-1981 and A-EA-1984 viruses, exhibited broad cross-neutralisation, towards more than 85% of the circulating viruses. Of the three vaccines, A-EA-2007 was the best showing more than 90% in-vitro cross-protection, as well as being the most recent amongst the vaccine strains used in this study. It therefore appears antigenically suitable as a vaccine strain to be used in the region in FMD control programmes. PMID:25171846

Assessment of the repeatability and border-plate effects of the B158/B60 enzyme-linked-immunosorbent assay for the detection of circulating antigens (Ag-ELISA) of Taenia saginata.

PubMed

Jansen, Famke; Dorny, Pierre; Berkvens, Dirk; Van Hul, Anke; Van den Broeck, Nick; Makay, Caroline; Praet, Nicolas; Gabriël, Sarah

2016-08-30

The monoclonal antibody-based circulating antigen detecting ELISA (B158/B60 Ag-ELISA) has been used elaborately in several studies for the diagnosis of human, bovine and porcine cysticercosis. Interpretation of test results requires a good knowledge of the test characteristics, including the repeatability and the effect of the borders of the ELISA plates. Repeatability was tested for 4 antigen-negative and 5 antigen-positive reference bovine serum samples by calculating the Percentage Coefficient of Variation (%CV) within and between plates, within and between runs, overall, for two batches of monoclonal antibodies and by 2 laboratory technicians. All CV values obtained were below 20% (except one: 24.45%), which indicates a good repeatability and a negligible technician error. The value of 24.45% for indicating the variability between batches of monoclonal antibodies for one positive sample is still acceptable for repeatability measures. Border effects were determined by calculating the %CV values between the inner and outer wells of one plate for 2 positive serum samples. Variability is a little more present in the outer wells but this effect is very small and no significant border effect was found. Copyright © 2016 Elsevier B.V. All rights reserved.

The Molecular Determinants of Antibody Recognition and Antigenic Drift in the H3 Hemagglutinin of Swine Influenza A Virus

PubMed Central

Abente, Eugenio J.; Santos, Jefferson; Lewis, Nicola S.; Gauger, Phillip C.; Stratton, Jered; Skepner, Eugene; Rajao, Daniela S.

2016-01-01

ABSTRACT Influenza A virus (IAV) of the H3 subtype is an important respiratory pathogen that affects both humans and swine. Vaccination to induce neutralizing antibodies against the surface glycoprotein hemagglutinin (HA) is the primary method used to control disease. However, due to antigenic drift, vaccine strains must be periodically updated. Six of the 7 positions previously identified in human seasonal H3 (positions 145, 155, 156, 158, 159, 189, and 193) were also indicated in swine H3 antigenic evolution. To experimentally test the effect on virus antigenicity of these 7 positions, substitutions were introduced into the HA of an isogenic swine lineage virus. We tested the antigenic effect of these introduced substitutions by using hemagglutination inhibition (HI) data with monovalent swine antisera and antigenic cartography to evaluate the antigenic phenotype of the mutant viruses. Combinations of substitutions within the antigenic motif caused significant changes in antigenicity. One virus mutant that varied at only two positions relative to the wild type had a >4-fold reduction in HI titers compared to homologous antisera. Potential changes in pathogenesis and transmission of the double mutant were evaluated in pigs. Although the double mutant had virus shedding titers and transmissibility comparable to those of the wild type, it caused a significantly lower percentage of lung lesions. Elucidating the antigenic effects of specific amino acid substitutions at these sites in swine H3 IAV has important implications for understanding IAV evolution within pigs as well as for improved vaccine development and control strategies in swine. IMPORTANCE A key component of influenza virus evolution is antigenic drift mediated by the accumulation of amino acid substitutions in the hemagglutinin (HA) protein, resulting in escape from prior immunity generated by natural infection or vaccination. Understanding which amino acid positions of the HA contribute to the ability of the virus to avoid prior immunity is important for understanding antigenic evolution and informs vaccine efficacy predictions based on the genetic sequence data from currently circulating strains. Following our previous work characterizing antigenic phenotypes of contemporary wild-type swine H3 influenza viruses, we experimentally validated that substitutions at 6 amino acid positions in the HA protein have major effects on antigenicity. An improved understanding of the antigenic diversity of swine influenza will facilitate a rational approach for selecting more effective vaccine components to control the circulation of influenza in pigs and reduce the potential for zoonotic viruses to emerge. PMID:27384658

A role for mitochondria in antigen processing and presentation

PubMed Central

Bonifaz, Laura C; Cervantes-Silva, Mariana P; Ontiveros-Dotor, Elizabeth; López-Villegas, Edgar O; Sánchez-García, F Javier

2015-01-01

Immune synapse formation is critical for T-lymphocyte activation, and mitochondria have a role in this process, by localizing close to the immune synapse, regulating intracellular calcium concentration, and providing locally required ATP. The interaction between antigen-presenting cells (APCs) and T lymphocytes is a two-way signalling process. However, the role of mitochondria in APCs during this process remains unknown. For APCs to be able to activate T lymphocytes, they must first engage in an antigen-uptake, -processing and -presentation process. Here we show that hen egg white lysozyme (HEL) -loaded B lymphocytes, as a type of APC, undergo a small but significant mitochondrial depolarization by 1–2 hr following antigen exposure, suggesting an increase in their metabolic demands. Inhibition of ATP synthase (oligomycin) or mitochondrial Ca2+ uniporter (MCU) (Ruthenium red) had no effect on antigen uptake. Therefore, antigen processing and antigen presentation were further analysed. Oligomycin treatment reduced the amount of specific MHC–peptide complexes but not total MHC II on the cell membrane of B lymphocytes, which correlated with a decrease in antigen presentation. However, oligomycin also reduced antigen presentation by B lymphocytes, which endogenously express HEL and by B lymphocytes loaded with the HEL48–62 peptide, although to a lesser extent. ATP synthase inhibition and MCU inhibition had a clear inhibitory effect on antigen processing (DQ-OVA). Taken together these results suggest that ATP synthase and MCU are relevant for antigen processing and presentation. Finally, APC mitochondria were found to re-organize towards the APC–T immune synapse. PMID:25251370

Development of high-yield influenza B virus vaccine viruses

PubMed Central

Ping, Jihui; Lopes, Tiago J. S.; Neumann, Gabriele; Kawaoka, Yoshihiro

2016-01-01

The burden of human infections with influenza A and B viruses is substantial, and the impact of influenza B virus infections can exceed that of influenza A virus infections in some seasons. Over the past few decades, viruses of two influenza B virus lineages (Victoria and Yamagata) have circulated in humans, and both lineages are now represented in influenza vaccines, as recommended by the World Health Organization. Influenza B virus vaccines for humans have been available for more than half a century, yet no systematic efforts have been undertaken to develop high-yield candidates. Therefore, we screened virus libraries possessing random mutations in the six “internal” influenza B viral RNA segments [i.e., those not encoding the major viral antigens, hemagglutinin (HA) and neuraminidase NA)] for mutants that confer efficient replication. Candidate viruses that supported high yield in cell culture were tested with the HA and NA genes of eight different viruses of the Victoria and Yamagata lineages. We identified combinations of mutations that increased the titers of candidate vaccine viruses in mammalian cells used for human influenza vaccine virus propagation and in embryonated chicken eggs, the most common propagation system for influenza viruses. These influenza B virus vaccine backbones can be used for improved vaccine virus production. PMID:27930325

Generation and protective efficacy of a cold-adapted attenuated avian H9N2 influenza vaccine.

PubMed

Wei, Yandi; Qi, Lu; Gao, Huijie; Sun, Honglei; Pu, Juan; Sun, Yipeng; Liu, Jinhua

2016-07-26

To prevent H9N2 avian influenza virus infection in chickens, a long-term vaccination program using inactivated vaccines has been implemented in China. However, the protective efficacy of inactivated vaccines against antigenic drift variants is limited, and H9N2 influenza virus continues to circulate in vaccinated chicken flocks in China. Therefore, developing a cross-reactive vaccine to control the impact of H9N2 influenza in the poultry industry remains a high priority. In the present study, we developed a live cold-adapted H9N2 influenza vaccine candidate (SD/01/10-ca) by serial passages in embryonated eggs at successively lower temperatures. A total of 13 amino acid mutations occurred during the cold-adaptation of this H9N2 virus. The candidate was safe in chickens and induced robust hemagglutination-inhibition antibody responses and influenza virus-specific CD4(+) and CD8(+) T cell immune responses in chickens immunized intranasally. Importantly, the candidate could confer protection of chickens from homologous and heterogenous H9N2 viruses. These results demonstrated that the cold-adapted attenuated H9N2 virus would be selected as a vaccine to control the infection of prevalent H9N2 influenza viruses in chickens.

Development of high-yield influenza B virus vaccine viruses.

PubMed

Ping, Jihui; Lopes, Tiago J S; Neumann, Gabriele; Kawaoka, Yoshihiro

2016-12-20

The burden of human infections with influenza A and B viruses is substantial, and the impact of influenza B virus infections can exceed that of influenza A virus infections in some seasons. Over the past few decades, viruses of two influenza B virus lineages (Victoria and Yamagata) have circulated in humans, and both lineages are now represented in influenza vaccines, as recommended by the World Health Organization. Influenza B virus vaccines for humans have been available for more than half a century, yet no systematic efforts have been undertaken to develop high-yield candidates. Therefore, we screened virus libraries possessing random mutations in the six "internal" influenza B viral RNA segments [i.e., those not encoding the major viral antigens, hemagglutinin (HA) and neuraminidase NA)] for mutants that confer efficient replication. Candidate viruses that supported high yield in cell culture were tested with the HA and NA genes of eight different viruses of the Victoria and Yamagata lineages. We identified combinations of mutations that increased the titers of candidate vaccine viruses in mammalian cells used for human influenza vaccine virus propagation and in embryonated chicken eggs, the most common propagation system for influenza viruses. These influenza B virus vaccine backbones can be used for improved vaccine virus production.

Generation and protective efficacy of a cold-adapted attenuated avian H9N2 influenza vaccine

PubMed Central

Wei, Yandi; Qi, Lu; Gao, Huijie; Sun, Honglei; Pu, Juan; Sun, Yipeng; Liu, Jinhua

2016-01-01

To prevent H9N2 avian influenza virus infection in chickens, a long-term vaccination program using inactivated vaccines has been implemented in China. However, the protective efficacy of inactivated vaccines against antigenic drift variants is limited, and H9N2 influenza virus continues to circulate in vaccinated chicken flocks in China. Therefore, developing a cross-reactive vaccine to control the impact of H9N2 influenza in the poultry industry remains a high priority. In the present study, we developed a live cold-adapted H9N2 influenza vaccine candidate (SD/01/10-ca) by serial passages in embryonated eggs at successively lower temperatures. A total of 13 amino acid mutations occurred during the cold-adaptation of this H9N2 virus. The candidate was safe in chickens and induced robust hemagglutination-inhibition antibody responses and influenza virus–specific CD4+ and CD8+ T cell immune responses in chickens immunized intranasally. Importantly, the candidate could confer protection of chickens from homologous and heterogenous H9N2 viruses. These results demonstrated that the cold-adapted attenuated H9N2 virus would be selected as a vaccine to control the infection of prevalent H9N2 influenza viruses in chickens. PMID:27457755

A new rapid diagnostic test for detection of anti-Schistosoma mansoni and anti-Schistosoma haematobium antibodies

PubMed Central

2013-01-01

Background Parasitological methods are widely used for the diagnosis of schistosomiasis. However, they are insensitive, particularly in areas of low endemicity, and labour-intensive. Immunoassays based on detection of anti-schistosome antibodies have the merit of high sensitivity and recently a rapid diagnostic test (RDT), incorporating Schistosoma mansoni cercarial transformation fluid (SmCTF) for detection of anti-schistosome antibodies in blood has been developed. Here, we assessed the diagnostic performance of the SmCTF-RDT for S. mansoni and S. haematobium infections by comparing it with microscopy for egg detection. Methods A cross-sectional survey was carried out in Azaguié, south Côte d’Ivoire. 118 pre-school-aged children submitted two stool and two urine samples, which were subjected to the Kato-Katz and urine filtration methods for the detection of S. mansoni and S. haematobium eggs, respectively. Urine was also subjected to a commercially available cassette test for S. mansoni, which detects circulating cathodic antigen. A finger-prick blood sample was used for the SmCTF-RDT for detection of anti-S. mansoni and anti-S. haematobium antibodies. Results The prevalence of both anti-S. mansoni and anti-S. haematobium antibodies was more than three times higher than the prevalence of infection estimated by egg detection under a microscope. Using quadruplicate Kato-Katz as the reference standard for the diagnosis of S. mansoni infection, the sensitivity, negative predictive value (NPV), and positive predictive value (PPV) of the SmCTF-RDT was 75.0%, 84.2% and 22.5%, respectively. When two urine filtrations were considered as the reference standard for the diagnosis of S. haematobium infection, the sensitivity, NPV and PPV of SmCTF-RDT was 66.7%, 94.9% and 5.1%, respectively. The specificity of SmCTF-RDT, when using egg-detection as the reference standard, was estimated to be 34.4%. This low specificity may be a reflection of the relative insensitivity of the direct diagnostic approaches using microscopy. Conclusions The SmCTF-RDT is at least as sensitive as duplicate Kato-Katz and a single urine filtration for detection of S. mansoni and S. haematobium, respectively. Further investigations into the specificity of the test for anti-schistosome antibodies are necessary, but our results suggest that it may be a useful tool for mapping the prevalence of anti-schistosome antibodies in a given population pending intervention. PMID:23360734

The Drosophila cell adhesion molecule Neuroglian regulates Lissencephaly-1 localisation in circulating immunosurveillance cells.

PubMed

Williams, Michael J

2009-03-25

When the parasitoid wasp Leptopilina boulardi lays its eggs in Drosophila larvae phagocytic cells called plasmatocytes and specialized cells known as lamellocytes encapsulate the egg. This requires these circulating immunosurveillance cells (haemocytes) to change from a non-adhesive to an adhesive state enabling them to bind to the invader. Interestingly, attachment of leukocytes, platelets, and insect haemocytes requires the same adhesion complexes as epithelial and neuronal cells. Here evidence is presented showing that the Drosophila L1-type cell adhesion molecule Neuroglian (Nrg) is required for haemocytes to encapsulate L. boulardi wasp eggs. The amino acid sequence FIGQY containing a conserved phosphorylated tyrosine is found in the intracellular domain of all L1-type cell adhesion molecules. This conserved tyrosine is phosphorylated at the cell periphery of plasmatocytes and lamellocytes prior to parasitisation, but dephosphorylated after immune activation. Intriguingly, another pool of Nrg located near the nucleus of plasmatocytes remains phosphorylated after parasitisation. In mammalian neuronal cells phosphorylated neurofascin, another L1-type cell adhesion molecule interacts with a nucleokinesis complex containing the microtubule binding protein lissencephaly-1 (Lis1) 1. Interestingly in plasmatocytes from Nrg mutants the nucleokinesis regulating protein Lissencephaly-1 (Lis1) fails to localise properly around the nucleus and is instead found diffuse throughout the cytoplasm and at unidentified perinuclear structures. After attaching to the wasp egg control plasmatocytes extend filopodia laterally from their cell periphery; as well as extending lateral filopodia plasmatocytes from Nrg mutants also extend many filopodia from their apical surface. The Drosophila cellular adhesion molecule Neuroglian is expressed in haemocytes and its activity is required for the encapsulation of L. boularli eggs. At the cell periphery of haemocytes Neuroglian may be involved in cell-cell interactions, while at the cell centre Neuroglian regulates the localisation of the nucleokinesis complex protein lissencephaly-1.

The Drosophila cell adhesion molecule Neuroglian regulates Lissencephaly-1 localisation in circulating immunosurveillance cells

PubMed Central

Williams, Michael J

2009-01-01

Background When the parasitoid wasp Leptopilina boulardi lays its eggs in Drosophila larvae phagocytic cells called plasmatocytes and specialized cells known as lamellocytes encapsulate the egg. This requires these circulating immunosurveillance cells (haemocytes) to change from a non-adhesive to an adhesive state enabling them to bind to the invader. Interestingly, attachment of leukocytes, platelets, and insect haemocytes requires the same adhesion complexes as epithelial and neuronal cells. Results Here evidence is presented showing that the Drosophila L1-type cell adhesion molecule Neuroglian (Nrg) is required for haemocytes to encapsulate L. boulardi wasp eggs. The amino acid sequence FIGQY containing a conserved phosphorylated tyrosine is found in the intracellular domain of all L1-type cell adhesion molecules. This conserved tyrosine is phosphorylated at the cell periphery of plasmatocytes and lamellocytes prior to parasitisation, but dephosphorylated after immune activation. Intriguingly, another pool of Nrg located near the nucleus of plasmatocytes remains phosphorylated after parasitisation. In mammalian neuronal cells phosphorylated neurofascin, another L1-type cell adhesion molecule interacts with a nucleokinesis complex containing the microtubule binding protein lissencephaly-1 (Lis1) [1]. Interestingly in plasmatocytes from Nrg mutants the nucleokinesis regulating protein Lissencephaly-1 (Lis1) fails to localise properly around the nucleus and is instead found diffuse throughout the cytoplasm and at unidentified perinuclear structures. After attaching to the wasp egg control plasmatocytes extend filopodia laterally from their cell periphery; as well as extending lateral filopodia plasmatocytes from Nrg mutants also extend many filopodia from their apical surface. Conclusion The Drosophila cellular adhesion molecule Neuroglian is expressed in haemocytes and its activity is required for the encapsulation of L. boularli eggs. At the cell periphery of haemocytes Neuroglian may be involved in cell-cell interactions, while at the cell centre Neuroglian regulates the localisation of the nucleokinesis complex protein lissencephaly-1. PMID:19320973

New vaccines against influenza virus

PubMed Central

Lee, Young-Tae; Kim, Ki-Hye; Ko, Eun-Ju; Lee, Yu-Na; Kim, Min-Chul; Kwon, Young-Man; Tang, Yinghua; Cho, Min-Kyoung; Lee, Youn-Jeong

2014-01-01

Vaccination is one of the most effective and cost-benefit interventions that prevent the mortality and reduce morbidity from infectious pathogens. However, the licensed influenza vaccine induces strain-specific immunity and must be updated annually based on predicted strains that will circulate in the upcoming season. Influenza virus still causes significant health problems worldwide due to the low vaccine efficacy from unexpected outbreaks of next epidemic strains or the emergence of pandemic viruses. Current influenza vaccines are based on immunity to the hemagglutinin antigen that is highly variable among different influenza viruses circulating in humans and animals. Several scientific advances have been endeavored to develop universal vaccines that will induce broad protection. Universal vaccines have been focused on regions of viral proteins that are highly conserved across different virus subtypes. The strategies of universal vaccines include the matrix 2 protein, the hemagglutinin HA2 stalk domain, and T cell-based multivalent antigens. Supplemented and/or adjuvanted vaccination in combination with universal target antigenic vaccines would have much promise. This review summarizes encouraging scientific advances in the field with a focus on novel vaccine designs. PMID:24427759

A dual purpose universal influenza vaccine candidate confers protective immunity against anthrax.

PubMed

Arévalo, Maria T; Li, Junwei; Diaz-Arévalo, Diana; Chen, Yanping; Navarro, Ashley; Wu, Lihong; Yan, Yongyong; Zeng, Mingtao

2017-03-01

Preventive influenza vaccines must be reformulated annually because of antigen shift and drift of circulating influenza viral strains. However, seasonal vaccines do not always match the circulating strains, and there is the ever-present threat that avian influenza viruses may adapt to humans. Hence, a universal influenza vaccine is needed to provide protective immunity against a broad range of influenza viruses. We designed an influenza antigen consisting of three tandem M2e repeats plus HA2, in combination with a detoxified anthrax oedema toxin delivery system (EFn plus PA) to enhance immune responses. The EFn-3×M2e-HA2 plus PA vaccine formulation elicited robust, antigen-specific, IgG responses; and was protective against heterologous influenza viral challenge when intranasally delivered to mice three times. Moreover, use of the detoxified anthrax toxin system as an adjuvant had the additional benefit of generating protective immunity against anthrax. Hence, this novel vaccine strategy could potentially address two major emerging public health and biodefence threats. © 2016 John Wiley & Sons Ltd.

[Extramembranous glomerulonephritis of acquired syphilis in a patient recently infected by the hepatitis B virus. Demonstration of the treponemal antigen in the kidney by indirect immunofluorescence].

PubMed

Schillinger, F; Montagnac, R; Goclowski, C; Dine, G; Alessandri, E; Hopfner, C; Birembaut, P

1983-01-22

A 38 years old male homosexual with active secondary syphilis presented with pure nephrotic syndrome while HBs and HBe tests were positive without clinical hepatitis. He had circulating immune complexes, IgG--IgM cryoglobulinemia and high IgA, IgM and IgE levels; the C3 and C4 complement constituents were normal. Examination of renal biopsy sections under light, fluorescent and electronic microscopy showed stage I membranous glomerulonephritis the syphilitic origin of which was confirmed by indirect immunofluorescence and by rapid cure under penicillin treatment. This case calls for the following comments: (1) glomerular deposits are extramembranous rather than subendothelial in syphilitic nephrosis, a disease now classified among circulating immune complexes diseases; (2) in the kidney, the treponema antigen can be demonstrated by indirect immunofluorescence and the anti-treponema antibody, by elution; (3) the outcome of the nephrotic syndrome is always favourable, either spontaneously or after penicillin treatment; (4) syphilis and HBs antigens are frequently associated, particularly in homosexual patients; one should be looked for when the other is discovered.

Factors regulating early life history dispersal of Atlantic cod (Gadus morhua) from coastal Newfoundland.

PubMed

Stanley, Ryan R E; deYoung, Brad; Snelgrove, Paul V R; Gregory, Robert S

2013-01-01

To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1) with a net mortality of 27%•day(-1). Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

Preparation and mass spectrometric study of egg yolk antibody (IgY) against rabies virus.

PubMed

Sun, S; Mo, W; Ji, Y; Liu, S

2001-01-01

Rabies virus was used as the antigen to immunize laying chickens. Anti-rabies virus immunoglobulin Y(IgY) was isolated from yolks of the eggs laid by these chickens using a two-step salt precipitation and one-step gel filtration protocol. The purified IgY was reduced with dithiothreitol, and heavy chains (HC) and light chains (LC) were obtained. In addition, the purified IgY was digested with pepsin and the fragment with specific antigen binding properties (Fab) was produced. Using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOFMS), the average molecular weights of IgY, HC, LC, and Fab were determined as 167 250, 65 105, 18 660, and 45,359 Da, respectively. IgY has two structural differences compared with mammalian IgGs. First, the molecular weight of the heavy chain of IgY is larger than that of its mammalian counterpart, while the molecular weight of the light chain of IgY is smaller. Second, upon pepsin digestion, anti-rabies virus IgY is degraded into Fab, in contrast to mammalian IgG, which has been reported to be degraded into F(ab')(2) under the same conditions. Copyright 2001 John Wiley & Sons, Ltd.

The Effect of In Vivo Hydrocortisone on Subpopulations of Human Lymphocytes

PubMed Central

Fauci, Anthony S.; Dale, David C.

1974-01-01

This study was designed to determine the effect of in vivo hydrocortisone on subpopulations of lymphoid cells in normal humans. Subjects received a single intravenous dose of either 100 mg or 400 mg of hydrocortisone, and blood was drawn at hourly intervals for 6 h, and then again at 10 and 24 h after injection. Profound decreases in absolute numbers of circulating lymphocytes and monocytes occurred at 4-6 h after both 100 mg and 400 mg of hydrocortisone. Counts returned to normal by 24 h. The relative proportion of circulating thymus-derived lymphocytes as measured by the sheep red blood cell rosette assay decreased maximally by 4 h and returned to base line 24 h after hydrocortisone. There was a selective depletion of functional subpopulations of lymphocytes as represented by differential effects on in vitro stimulation with various mitogens and antigens. Phytohaemagglutinin response was relatively unaffected, while responses to concanavalin A were significantly diminished. Responses to pokeweed mitogen were unaffected by 100 mg of hydrocortisone, but greatly diminished by 400 mg of hydrocortisone. In vitro responses to the antigens streptokinase-streptodornase and tetanus toxoid were markedly diminished by in vivo hydrocortisone. Reconstitution of monocyte-depleted cultures with autologous monocytes partially corrected the diminished response to antigens. This transient selective depletion of monocytes and subsets of human lymphocytes by a single dose of hydrocortisone is most compatible with a redistribution of these cells out of the circulation into other body compartments. Images PMID:4808638

Molecular and serological survey on taeniasis and cysticercosis in Kanchanaburi Province, Thailand.

PubMed

Anantaphruti, Malinee T; Okamoto, Munehiro; Yoonuan, Tippayarat; Saguankiat, Surapol; Kusolsuk, Teera; Sato, Megumi; Sato, Marcello O; Sako, Yasuhito; Waikagul, Jitra; Ito, Akira

2010-09-01

A community-based field survey on taeniasis and cysticercosis was performed in two villages in Thong Pha Phum District, Kanchanaburi Province, central Thailand, where 3 Taenia species, T. solium, T. saginata and T. asiatica, are sympatrically occurring. Four (0.6%) out of 667 stool samples were egg-positive for Taenia sp. by Kato-Katz technique. Three out of those four persons and other three persons who were Taenia egg-negative but having a recent (<1 year) history of discharging worms in stool were treated with niclosamide. One Taenia egg-positive woman was not treated because of severe ascites. After treatment, three persons expelled long strobilae with scolices and two persons expelled strobilae without scolex. One Taenia egg-positive person did not expel any worms post-treatment. Among 5 persons, four expelled a single worm, whereas one expelled multiple worms, may be 6 worms but not confirmed by detection of scolices. One scolex was armed with hooklets, whereas 2 others did not. Multiplex PCR of 10 expelled proglottids (including 6 estimated worms from one patient) revealed that one sample was T. solium, one T. saginata, and 8 T. asiatica. A total of 159 residents agreed to receive a serological test for cysticercosis. By ELISA using partially purified glycoprotein antigen, 9 cases, 5 and 4 from villages A and B respectively, were found to be sero-positive. The five and an additional sample on the border line from village A were evaluated using confirmative immunoblot using recombinant chimeric antigen. Among the six samples, four including the border line sample were confirmed to be cysticercosis by immunoblotting. One of the 4 persons had neurological symptoms with nodular lesions in the brain by computed tomography. These 4 confirmed or suspected cysticercosis cases were free of T. solium worms, but two of them including confirmed NCC case had a past (>1 year) history of expelling proglottids in the stool.

The Diagnosis of Human Fascioliasis by Enzyme-Linked Immunosorbent Assay (ELISA) Using Recombinant Cathepsin L Protease

PubMed Central

Gonzales Santana, Bibiana; Vasquez Camargo, Fabio; Parkinson, Michael

2013-01-01

Background Fascioliasis is a worldwide parasitic disease of domestic animals caused by helminths of the genus Fasciola. In many parts of the world, particularly in poor rural areas where animal disease is endemic, the parasite also infects humans. Adult parasites reside in the bile ducts of the host and therefore diagnosis of human fascioliasis is usually achieved by coprological examinations that search for parasite eggs that are carried into the intestine with the bile juices. However, these methods are insensitive due to the fact that eggs are released sporadically and may be missed in low-level infections, and fasciola eggs may be misclassified as other parasites, leading to problems with specificity. Furthermore, acute clinical symptoms as a result of parasites migrating to the bile ducts appear before the parasite matures and begins egg laying. A human immune response to Fasciola antigens occurs early in infection. Therefore, an immunological method such as ELISA may be a more reliable, easy and cheap means to diagnose human fascioliasis than coprological analysis. Methodology/Principal findings Using a panel of serum from Fasciola hepatica-infected patients and from uninfected controls we have optimized an enzyme-linked immunosorbent assay (ELISA) which employs a recombinant form of the major F. hepatica cathepsin L1 as the antigen for the diagnosis of human fascioliasis. We examined the ability of the ELISA test to discern fascioliasis from various other helminth and non-helminth parasitic diseases. Conclusions/Significance A sensitive and specific fascioliasis ELISA test has been developed. This test is rapid and easy to use and can discriminate fasciola-infected individuals from patients harbouring other parasites with at least 99.9% sensitivity and 99.9% specificity. This test will be a useful standardized method not only for testing individual samples but also in mass screening programs to assess the extent of human fascioliasis in regions where this zoonosis is suspected. PMID:24069474

The diagnosis of human fascioliasis by enzyme-linked immunosorbent assay (ELISA) using recombinant cathepsin L protease.

PubMed

Gonzales Santana, Bibiana; Dalton, John P; Vasquez Camargo, Fabio; Parkinson, Michael; Ndao, Momar

2013-01-01

Fascioliasis is a worldwide parasitic disease of domestic animals caused by helminths of the genus Fasciola. In many parts of the world, particularly in poor rural areas where animal disease is endemic, the parasite also infects humans. Adult parasites reside in the bile ducts of the host and therefore diagnosis of human fascioliasis is usually achieved by coprological examinations that search for parasite eggs that are carried into the intestine with the bile juices. However, these methods are insensitive due to the fact that eggs are released sporadically and may be missed in low-level infections, and fasciola eggs may be misclassified as other parasites, leading to problems with specificity. Furthermore, acute clinical symptoms as a result of parasites migrating to the bile ducts appear before the parasite matures and begins egg laying. A human immune response to Fasciola antigens occurs early in infection. Therefore, an immunological method such as ELISA may be a more reliable, easy and cheap means to diagnose human fascioliasis than coprological analysis. Using a panel of serum from Fasciola hepatica-infected patients and from uninfected controls we have optimized an enzyme-linked immunosorbent assay (ELISA) which employs a recombinant form of the major F. hepatica cathepsin L1 as the antigen for the diagnosis of human fascioliasis. We examined the ability of the ELISA test to discern fascioliasis from various other helminth and non-helminth parasitic diseases. A sensitive and specific fascioliasis ELISA test has been developed. This test is rapid and easy to use and can discriminate fasciola-infected individuals from patients harbouring other parasites with at least 99.9% sensitivity and 99.9% specificity. This test will be a useful standardized method not only for testing individual samples but also in mass screening programs to assess the extent of human fascioliasis in regions where this zoonosis is suspected.

Global circulation patterns of seasonal influenza viruses vary with antigenic drift

PubMed Central

Bedford, Trevor; Riley, Steven; Barr, Ian G.; Broor, Shobha; Chadha, Mandeep; Cox, Nancy J.; Daniels, Rodney S.; Gunasekaran, C. Palani; Hurt, Aeron C.; Kelso, Anne; Lewis, Nicola S.; Li, Xiyan; McCauley, John W.; Odagiri, Takato; Potdar, Varsha; Rambaut, Andrew; Shu, Yuelong; Skepner, Eugene; Smith, Derek J.; Suchard, Marc A.; Tashiro, Masato; Wang, Dayan; Xu, Xiyan; Lemey, Philippe; Russell, Colin A.

2015-01-01

Understanding the spatio-temporal patterns of emergence and circulation of new human seasonal influenza virus variants is a key scientific and public health challenge. The global circulation patterns of influenza A/H3N2 viruses are well-characterized1-7 but the patterns of A/H1N1 and B viruses have remained largely unexplored. Here, based on analyses of 9,604 hemagglutinin sequences of human seasonal influenza viruses from 2000–2012, we show that the global circulation patterns of A/H1N1 (up to 2009), B/Victoria, and B/Yamagata viruses differ substantially from those of A/H3N2 viruses. While genetic variants of A/H3N2 viruses did not persist locally between epidemics and were reseeded from East and Southeast (E-SE) Asia, genetic variants of A/H1N1 and B viruses persisted across multiple seasons and exhibited complex global dynamics with E-SE Asia playing a limited role in disseminating new variants. The less frequent global movement of influenza A/H1N1 and B viruses coincided with slower rates of antigenic evolution, lower ages of infection, and smaller less frequent epidemics compared to A/H3N2 viruses. Detailed epidemic models support differences in age of infection, combined with the less frequent travel of children, as likely drivers of the differences in the patterns of global circulation, suggesting a complex interaction between virus evolution, epidemiology and human behavior. PMID:26053121

Global circulation patterns of seasonal influenza viruses vary with antigenic drift

NASA Astrophysics Data System (ADS)

Bedford, Trevor; Riley, Steven; Barr, Ian G.; Broor, Shobha; Chadha, Mandeep; Cox, Nancy J.; Daniels, Rodney S.; Gunasekaran, C. Palani; Hurt, Aeron C.; Kelso, Anne; Klimov, Alexander; Lewis, Nicola S.; Li, Xiyan; McCauley, John W.; Odagiri, Takato; Potdar, Varsha; Rambaut, Andrew; Shu, Yuelong; Skepner, Eugene; Smith, Derek J.; Suchard, Marc A.; Tashiro, Masato; Wang, Dayan; Xu, Xiyan; Lemey, Philippe; Russell, Colin A.

2015-07-01

Understanding the spatiotemporal patterns of emergence and circulation of new human seasonal influenza virus variants is a key scientific and public health challenge. The global circulation patterns of influenza A/H3N2 viruses are well characterized, but the patterns of A/H1N1 and B viruses have remained largely unexplored. Here we show that the global circulation patterns of A/H1N1 (up to 2009), B/Victoria, and B/Yamagata viruses differ substantially from those of A/H3N2 viruses, on the basis of analyses of 9,604 haemagglutinin sequences of human seasonal influenza viruses from 2000 to 2012. Whereas genetic variants of A/H3N2 viruses did not persist locally between epidemics and were reseeded from East and Southeast Asia, genetic variants of A/H1N1 and B viruses persisted across several seasons and exhibited complex global dynamics with East and Southeast Asia playing a limited role in disseminating new variants. The less frequent global movement of influenza A/H1N1 and B viruses coincided with slower rates of antigenic evolution, lower ages of infection, and smaller, less frequent epidemics compared to A/H3N2 viruses. Detailed epidemic models support differences in age of infection, combined with the less frequent travel of children, as probable drivers of the differences in the patterns of global circulation, suggesting a complex interaction between virus evolution, epidemiology, and human behaviour.

Circulating precursor CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells indicate Tfh cell activity and promote antibody responses upon antigen reexposure.

PubMed

He, Jing; Tsai, Louis M; Leong, Yew Ann; Hu, Xin; Ma, Cindy S; Chevalier, Nina; Sun, Xiaolin; Vandenberg, Kirsten; Rockman, Steve; Ding, Yan; Zhu, Lei; Wei, Wei; Wang, Changqi; Karnowski, Alexander; Belz, Gabrielle T; Ghali, Joanna R; Cook, Matthew C; Riminton, D Sean; Veillette, André; Schwartzberg, Pamela L; Mackay, Fabienne; Brink, Robert; Tangye, Stuart G; Vinuesa, Carola G; Mackay, Charles R; Li, Zhanguo; Yu, Di

2013-10-17

Follicular B helper T (Tfh) cells support high affinity and long-term antibody responses. Here we found that within circulating CXCR5⁺ CD4⁺ T cells in humans and mice, the CCR7(lo)PD-1(hi) subset has a partial Tfh effector phenotype, whereas CCR7(hi)PD-1(lo) cells have a resting phenotype. The circulating CCR7(lo)PD-1(hi) subset was indicative of active Tfh differentiation in lymphoid organs and correlated with clinical indices in autoimmune diseases. Thus the CCR7(lo)PD-1(hi) subset provides a biomarker to monitor protective antibody responses during infection or vaccination and pathogenic antibody responses in autoimmune diseases. Differentiation of both CCR7(hi)PD-1(lo) and CCR7(lo)PD-1(hi) subsets required ICOS and BCL6, but not SAP, suggesting that circulating CXCR5⁺ helper T cells are primarily generated before germinal centers. Upon antigen reencounter, CCR7(lo)PD-1(hi) CXCR5⁺ precursors rapidly differentiate into mature Tfh cells to promote antibody responses. Therefore, circulating CCR7(lo)PD-1(hi) CXCR5⁺ CD4⁺ T cells are generated during active Tfh differentiation and represent a new mechanism of immunological early memory. Copyright © 2013 Elsevier Inc. All rights reserved.

Circulating rotavirus-specific T cells have a poor functional profile

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parra, Miguel; Herrera, Daniel; Jácome, María Fernanda

Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ{sup +} cells, while influenza-CD4 and tetanus toxoid-CD4more » T cell responses were enriched in multifunctional T cells. Moreover, rIL-2 – unlike rIL-12 or DGKα-i – increased the frequencies of RV-CD4 TNF-α{sup +}, CD4 IFN-γ{sup +}, and CD8 IFN-γ{sup +} cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. - Highlights: • The quality and magnitude of circulating RV-T cell responses are relatively poor. • Circulating RV-CD4 T cells are enriched in monofunctional IFN-γ+ cells. • Treatment with rIL-2 increased the frequencies of cytokine secreting RV-T cells.« less

Indirect presentation in the thymus limits naive and regulatory T-cell differentiation by promoting deletion of self-reactive thymocytes.

PubMed

Yap, Jin Yan; Wirasinha, Rushika C; Chan, Anna; Howard, Debbie R; Goodnow, Christopher C; Daley, Stephen R

2018-02-07

Acquisition of T-cell central tolerance involves distinct pathways of self-antigen presentation to thymocytes. One pathway termed indirect presentation requires a self-antigen transfer step from thymic epithelial cells (TECs) to bone marrow-derived cells before the self-antigen is presented to thymocytes. The role of indirect presentation in central tolerance is context-dependent, potentially due to variation in self-antigen expression, processing and presentation in the thymus. Here, we report experiments in mice in which TECs expressed a membrane-bound transgenic self-antigen, hen egg lysozyme (HEL), from either the insulin (insHEL) or thyroglobulin (thyroHEL) promoter. Intrathymic HEL expression was less abundant and more confined to the medulla in insHEL mice compared with thyroHEL mice. When indirect presentation was impaired by generating mice lacking MHC class II expression in bone marrow-derived antigen-presenting cells, insHEL-mediated thymocyte deletion was abolished, whereas thyroHEL-mediated deletion occurred at a later stage of thymocyte development and Foxp3 + regulatory T-cell differentiation increased. Indirect presentation increased the strength of T-cell receptor signalling that both self-antigens induced in thymocytes, as assessed by Helios expression. Hence, indirect presentation limits the differentiation of naive and regulatory T cells by promoting deletion of self-reactive thymocytes. © 2018 John Wiley & Sons Ltd.

Analysis of antigen-induced changes in pulmonary mechanics in sensitized inbred rats.

PubMed

Holroyde, M C; Smith, S Y; Holme, G

1982-05-01

An inbred line of rats was derived which develop marked and consistent dyspnea following sensitization and then exposure to aerosolized antigen. This pulmonary response was investigated in detail by determining forced pulmonary mechanics to derive respiratory rate, peak expiratory flow rate (PEFR), forced vital capacity (FVC), forced expiratory volume in 0.1 s (FEV0.1), and maximal midexpiratory flow rate (MMFR). Challenging anesthetized rats for 5 min with an aerosol of 3% egg albumin produced minimal change in respiratory rate, a 20% fall in PEFR, a 50% fall in FVC, and a 30% decrease in FEV0.1 and MMFR. The response could be inhibited or reversed by salbutamol (0.5 mg/kg, i.v.) and aminophylline (25 mg/kg, i.v.) administered either before or after challenge. The pulmonary changes are consistent with antigen-induced asthma in the rats. The response shows similarities to human asthma and may provide a relevant experimental model.

Immunoblot patterns of Taenia asiatica taeniasis.

PubMed

Jeon, Hyeong-Kyu; Eom, Keeseon S

2009-03-01

Differential diagnosis of Taenia asiatica infection from other human taeniases by serology has been tested. An enzyme-linked immunoelectrotransfer blot (EITB) was applied to subjected human sera and tapeworm materials. Thirty-eight proteins reactive to serum IgG were observed between 121 and 10 kDa in adult worms, and more than 22 serum-reactive components between 97 kDa and 21.5 kDa were observed in eggs of T. asiatica. Antigens of adult T. asiatica revealed immunoblot bands between 120 and 21.5 kDa against T. asiatica infected sera. Antigens of adult Taenia saginata revealed 110-100, 66, 58-56, and 46 kDa immunoblot bands against T. asiatica infected sera. Antigens of adult Taenia solium also revealed 99-97, 68-66, and 46 kDa bands against T. asiatica infected sera. The immunoblot band of 21.5 kDa exhibited specificity to T. asiatica.

Immunoblot Patterns of Taenia asiatica Taeniasis

PubMed Central

Jeon, Hyeong-Kyu

2009-01-01

Differential diagnosis of Taenia asiatica infection from other human taeniases by serology has been tested. An enzyme-linked immunoelectrotransfer blot (EITB) was applied to subjected human sera and tapeworm materials. Thirty-eight proteins reactive to serum IgG were observed between 121 and 10 kDa in adult worms, and more than 22 serum-reactive components between 97 kDa and 21.5 kDa were observed in eggs of T. asiatica. Antigens of adult T. asiatica revealed immunoblot bands between 120 and 21.5 kDa against T. asiatica infected sera. Antigens of adult Taenia saginata revealed 110-100, 66, 58-56, and 46 kDa immunoblot bands against T. asiatica infected sera. Antigens of adult Taenia solium also revealed 99-97, 68-66, and 46 kDa bands against T. asiatica infected sera. The immunoblot band of 21.5 kDa exhibited specificity to T. asiatica. PMID:19290097

[Evaluation of an ELISA test with Fasciola hepatica metabolic antigen for diagnosis of human fascioliasis in Cajamarca, Peru].

PubMed

Cornejo, Hernán; Oblitas, Fátima; Cruzado, Sandro; Quispe, William

2010-01-01

Metabolic (excretion/secretion) antigen was obtained from sheep infected with Fasciola hepatica, with a 1005 μg/μL of protein concentration, composed principally by proteins of molecular weight between 1.2 and 170 KDa. Bands of 170, 150, 31, 24, 18-14 and 10 kDa were detected. With this antigen an ELISA test was developed and the cut off was determined in 0.140. We evaluated 33 serums of patient with fascioliasis confirmed by visualization of eggs in feces, 177 serums of persons without fascioliasis from endemic rural areas of Cajamarca and 88 serums of patients with others parasitic and bacterial infections. We found a 97.0% of sensitivity, 96.6 specificity, 78.1% predictive positive value, 99.6 % predictive negative value. In 9/88 serums was found cross reactions. We recommended the implementation and use of this test for the fascioliasis diagnosis.

Discrete microfluidics for the isolation of circulating tumor cell subpopulations targeting fibroblast activation protein alpha and epithelial cell adhesion molecule.

PubMed

Witek, Małgorzata A; Aufforth, Rachel D; Wang, Hong; Kamande, Joyce W; Jackson, Joshua M; Pullagurla, Swathi R; Hupert, Mateusz L; Usary, Jerry; Wysham, Weiya Z; Hilliard, Dawud; Montgomery, Stephanie; Bae-Jump, Victoria; Carey, Lisa A; Gehrig, Paola A; Milowsky, Matthew I; Perou, Charles M; Soper, John T; Whang, Young E; Yeh, Jen Jen; Martin, George; Soper, Steven A

2017-01-01

Circulating tumor cells consist of phenotypically distinct subpopulations that originate from the tumor microenvironment. We report a circulating tumor cell dual selection assay that uses discrete microfluidics to select circulating tumor cell subpopulations from a single blood sample; circulating tumor cells expressing the established marker epithelial cell adhesion molecule and a new marker, fibroblast activation protein alpha, were evaluated. Both circulating tumor cell subpopulations were detected in metastatic ovarian, colorectal, prostate, breast, and pancreatic cancer patients and 90% of the isolated circulating tumor cells did not co-express both antigens. Clinical sensitivities of 100% showed substantial improvement compared to epithelial cell adhesion molecule selection alone. Owing to high purity (>80%) of the selected circulating tumor cells, molecular analysis of both circulating tumor cell subpopulations was carried out in bulk, including next generation sequencing, mutation analysis, and gene expression. Results suggested fibroblast activation protein alpha and epithelial cell adhesion molecule circulating tumor cells are distinct subpopulations and the use of these in concert can provide information needed to navigate through cancer disease management challenges.

Investigation of vesicle-capsular plague antigen complex formation by elastic laser radiation scattering

NASA Astrophysics Data System (ADS)

Guseva, N. P.; Maximova, Irina S.; Romanov, Sergey V.; Shubochkin, L. P.; Tatarintsev, Sergey N.

1991-05-01

Recently a great deal of attention has been given to the investigation artificial lipid liposomes, due to their application as "containers" for directed transport of biologically active compounds into particular cells, organs and tissues for prophylaxis and therapy of infectious diseases. The use of traditional methods of liposome investigation, such as sedimentation, electrophoresis and chromatography is impeded by low liposome resistivity to different deformations. In conjunction with this, optical methods of laser light scattering are promising as they allow nondisturbing, precise and quick investigations. This paper describes the investigation of vesicle systems prepared from egg lecithin of Serva Corporation and their complexes with the capsular antigen of the plague microbe. The capsular antigen Fl was obtained from EV plague microbe grown at 37° C on Huttinger agar. Fl was isolated by gel-filtration on ASA-22 followed by freeze drying of the preparation. Angular dependences of polarized radiation scattering were measured for several liposome suspension samples in a saline solution before and after the interaction with the plague microbe capsular antigen. The aim of the investigation was to analyze the nature of mutual antigen arrangement in a liposome and to develop methods for measuring its inclusion percentage.

Integrated Magneto-Chemical Sensor For On-Site Food Allergen Detection.

PubMed

Lin, Hsing-Ying; Huang, Chen-Han; Park, Jongmin; Pathania, Divya; Castro, Cesar M; Fasano, Alessio; Weissleder, Ralph; Lee, Hakho

2017-10-24

Adverse food reactions, including food allergies, food sensitivities, and autoimmune reaction (e.g., celiac disease) affect 5-15% of the population and remain a considerable public health problem requiring stringent food avoidance and epinephrine availability for emergency events. Avoiding problematic foods is practically difficult, given current reliance on prepared foods and out-of-home meals. In response, we developed a portable, point-of-use detection technology, termed integrated exogenous antigen testing (iEAT). The system consists of a disposable antigen extraction device coupled with an electronic keychain reader for rapid sensing and communication. We optimized the prototype iEAT system to detect five major food antigens in peanuts, hazelnuts, wheat, milk, and eggs. Antigen extraction and detection with iEAT requires <10 min and achieves high-detection sensitivities (e.g., 0.1 mg/kg for gluten, lower than regulatory limits of 20 mg/kg). When testing under restaurant conditions, we were able to detect hidden food antigens such as gluten within "gluten-free" food items. The small size and rapid, simple testing of the iEAT system should help not only consumers but also other key stakeholders such as clinicians, food industries, and regulators to enhance food safety.

In vitro antigen-induced, antigen-specific antibody production in man. Specific and polyclonal components, kinetics, and cellular requirements

PubMed Central

1981-01-01

A highly specific and reproducible antigen-induced, antigen-specific culture and assay system for antibody production by human peripheral blood B lymphocytes has been developed. The system is clearly T cell and monocyte dependent and is independent of exogenous mitogens. The major factors in our ability to trigger specific antibody production with antigen alone have been the use of extremely low concentrations of antigen in vitro (doses several orders of magnitude below those inducing a peak blastogenic response), careful attention to in vitro cell density and culture vessel geometry, and appreciation of the kinetics of the circulating antigen-inducible B cell repertoire. A dichotomy and overlap between antigen-induced, antigen-specific and antigen-induced, polyclonal responses was observed in the study of doubly immunized individuals. Whereas antibody responses highly specific for the antigen in culture were observed under one set of culture conditions (flat-bottomed vessels, 1.5 x 10(6) cells), switching to another culture system (round-bottomed vessels, 5 x 10(5) cells) resulted in polyclonal responses to antigen. Despite these culture condition-related differences in the induction of antibody synthesis, the suppression of specific antibody production that occurred at high concentrations of antigen was specific only for the antigen in culture. The capability to easily and reproducibly look at truly antigen-induced, antigen specific antibody production should be a major tool in furthering the understanding of human B cell activation and immunoregulation. PMID:6169778

Definition of Drosophila hemocyte subsets by cell-type specific antigens.

PubMed

Kurucz, Eva; Váczi, B; Márkus, R; Laurinyecz, Barbara; Vilmos, P; Zsámboki, J; Csorba, Kinga; Gateff, Elisabeth; Hultmark, D; Andó, I

2007-01-01

We analyzed the heterogeneity of Drosophila hemocytes on the basis of the expression of cell-type specific antigens. The antigens characterize distinct subsets which partially overlap with those defined by morphological criteria. On the basis of the expression or the lack of expression of blood cell antigens the following hemocyte populations have been defined: crystal cells, plasmatocytes, lamellocytes and precursor cells. The expression of the antigens and thus the different cell types are developmentally regulated. The hemocytes are arranged in four main compartments: the circulating blood cells, the sessile tissue, the lymph glands and the posterior hematopoietic tissue. Each hemocyte compartment has a specific and characteristic composition of the various cell types. The described markers represent the first successful attempt to define hemocyte lineages by immunological markers in Drosophila and help to define morphologically, functionally, spatially and developmentally distinct subsets of hemocytes.

Systemic cell-mediated reactions in vivo. Effect of the interaction of circulating antigen with sensitized lymphocytes on glomeruli and pulmonary alveoli.

PubMed Central

Bhan, A. K.; Schneeberger, E. E.; Collins, A. B.; McCluskey, R. T.

1984-01-01

The effects of systemic cell-mediated hypersensitivity reactions on glomeruli and lungs were investigated in rats. The animals were given an intravenous injection of antigen 7 days after sensitization or were given an intravenous injection of lymph node cells from sensitized syngeneic donors 1 day after antigen injection. Control animals were given an irrelevant antigen or saline. All animals received three injections of 3H-thymidine during the course of the experiments. The animals were sacrificed 2 or 3 days after antigen injection. Autoradiographs of renal and pulmonary tissue showed significantly more labeled mononuclear cells in glomeruli and pulmonary alveolar walls in the experimental groups than in the control groups. Immunofluorescence studies did not reveal antigen, rat IgG, or C3 in glomeruli. The results indicate that systemic cell-mediated reactions can lead to an accumulation of mononuclear cells in glomeruli and lungs, an effect that may contribute to tissue injury. Images Figure 1 Figure 2 Figure 3 PMID:6611090

Monitoring Spawning Activity in a Southern California Marine Protected Area Using Molecular Identification of Fish Eggs

PubMed Central

Harada, Alice E.; Lindgren, Elise A.; Hermsmeier, Maiko C.; Rogowski, Peter A.; Terrill, Eric; Burton, Ronald S.

2015-01-01

In order to protect the diverse ecosystems of coastal California, a series of marine protected areas (MPAs) have been established. The ability of these MPAs to preserve and potentially enhance marine resources can only be assessed if these habitats are monitored through time. This study establishes a baseline for monitoring the spawning activity of fish in the MPAs adjacent to Scripps Institution of Oceanography (La Jolla, CA, USA) by sampling fish eggs from the plankton. Using vertical plankton net tows, 266 collections were made from the Scripps Pier between 23 August 2012 and 28 August 2014; a total of 21,269 eggs were obtained. Eggs were identified using DNA barcoding: the COI or 16S rRNA gene was amplified from individual eggs and sequenced. All eggs that were successfully sequenced could be identified from a database of molecular barcodes of California fish species, resulting in species-level identification of 13,249 eggs. Additionally, a surface transport model of coastal circulation driven by current maps from high frequency radar was used to construct probability maps that estimate spawning locations that gave rise to the collected eggs. These maps indicated that currents usually come from the north but water parcels tend to be retained within the MPA; eggs sampled at the Scripps Pier have a high probability of having been spawned within the MPA. The surface transport model also suggests that although larvae have a high probability of being retained within the MPA, there is also significant spillover into nearby areas outside the MPA. This study provides an important baseline for addressing the extent to which spawning patterns of coastal California species may be affected by future changes in the ocean environment. PMID:26308928

Monitoring Spawning Activity in a Southern California Marine Protected Area Using Molecular Identification of Fish Eggs.

PubMed

Harada, Alice E; Lindgren, Elise A; Hermsmeier, Maiko C; Rogowski, Peter A; Terrill, Eric; Burton, Ronald S

2015-01-01

In order to protect the diverse ecosystems of coastal California, a series of marine protected areas (MPAs) have been established. The ability of these MPAs to preserve and potentially enhance marine resources can only be assessed if these habitats are monitored through time. This study establishes a baseline for monitoring the spawning activity of fish in the MPAs adjacent to Scripps Institution of Oceanography (La Jolla, CA, USA) by sampling fish eggs from the plankton. Using vertical plankton net tows, 266 collections were made from the Scripps Pier between 23 August 2012 and 28 August 2014; a total of 21,269 eggs were obtained. Eggs were identified using DNA barcoding: the COI or 16S rRNA gene was amplified from individual eggs and sequenced. All eggs that were successfully sequenced could be identified from a database of molecular barcodes of California fish species, resulting in species-level identification of 13,249 eggs. Additionally, a surface transport model of coastal circulation driven by current maps from high frequency radar was used to construct probability maps that estimate spawning locations that gave rise to the collected eggs. These maps indicated that currents usually come from the north but water parcels tend to be retained within the MPA; eggs sampled at the Scripps Pier have a high probability of having been spawned within the MPA. The surface transport model also suggests that although larvae have a high probability of being retained within the MPA, there is also significant spillover into nearby areas outside the MPA. This study provides an important baseline for addressing the extent to which spawning patterns of coastal California species may be affected by future changes in the ocean environment.

Cross-reactions with Ascaris suum antigens of sera from mice infected with A. suum, Toxocara canis, and Angiostrongylus cantonensis.

PubMed

Fan, Chia-Kwung; Su, Kua-Eyre

2004-09-01

Ascaris suum larval excretory-secretory (AsES) antigen and larval (AsLA) as well as adult somatic antigen (AsAA) which were thought to be possibly helpful in the diagnosis of visceral larva migrans (VLM) due to A. suum infection were investigated in the present study. Serum taken from mice orally inoculated with approximately 250 embryonated eggs of A. suum or Toxocara canis, or 40 third-stage larvae of Angiostrongylus cantonensis were assessed by enzyme-linked immunosorbent assay (ELISA) using the AsES antigen, AsLA or AsAA at 1, 2, 3, 4, 6 and 8 weeks post infection (WPI). The titer of serum IgG from mice infected with A. suum increased from 1 WPI and a peak at 4 WPI was observed when it reached approximately three times the level of uninfected control mice. Thereafter, it decreased gradually but remained high as found from 6 to 8 WPI. No cross-reactions of heterologous serum IgG against AsES antigen was observed, whereas heterologous serum IgM exhibited significant cross-reactions to AsES antigen. Cross-reactivities to AsLA and AsAA by heterologous serum IgG as well as IgM antibodies were also observed in the trial. Altogether, the AsES antigen apparently seemed to be superior to the other two somatic antigens when used in the diagnosis of A. suum-induced VLM with serum IgG as tested by ELISA. Moreover, it was the first report to test the possibly antigenic cross-reactivity between A. suum and A. cantonensis.

Specific T-cell activation in an unspecific T-cell repertoire.

PubMed

Van Den Berg, Hugo A; Molina-París, Carmen; Sewell, Andrew K

2011-01-01

T-cells are a vital type of white blood cell that circulate around our bodies, scanning for cellular abnormalities and infections. They recognise disease-associated antigens via a surface receptor called the T-cell antigen receptor (TCR). If there were a specific TCR for every single antigen, no mammal could possibly contain all the T-cells it needs. This is clearly absurd and suggests that T-cell recognition must, to the contrary, be highly degenerate. Yet highly promiscuous TCRs would appear to be equally impossible: they are bound to recognise self as well as non-self antigens. We review how contributions from mathematical analysis have helped to resolve the paradox of the promiscuous TCR. Combined experimental and theoretical work shows that TCR degeneracy is essentially dynamical in nature, and that the T-cell can differentially adjust its functional sensitivity to the salient epitope, "tuning up" sensitivity to the antigen associated with disease and "tuning down" sensitivity to antigens associated with healthy conditions. This paradigm of continual modulation affords the TCR repertoire, despite its limited numerical diversity, the flexibility to respond to almost any antigenic challenge while avoiding autoimmunity.

The Use of "Kryptolebias marmoratus" Eggs as an Educational Tool for Embryology Education

ERIC Educational Resources Information Center

Genade, Tyrone

2016-01-01

Plastic embryological models lack the excitement of seeing real, live embryos. Chick embryos are often used to demonstrate embryological development and blood circulation to students but this necessitates the death of the organism. "Kryptolebias marmoratus" embryos are large and can be viewed by means of a light microscope without need…

Transdifferentiation and Proliferation in Two Distinct Hemocyte Lineages in Drosophila melanogaster Larvae after Wasp Infection

PubMed Central

Ihalainen, Teemu O.; Vanha-aho, Leena-Maija; Andó, István; Rämet, Mika

2016-01-01

Cellular immune responses require the generation and recruitment of diverse blood cell types that recognize and kill pathogens. In Drosophila melanogaster larvae, immune-inducible lamellocytes participate in recognizing and killing parasitoid wasp eggs. However, the sequence of events required for lamellocyte generation remains controversial. To study the cellular immune system, we developed a flow cytometry approach using in vivo reporters for lamellocytes as well as for plasmatocytes, the main hemocyte type in healthy larvae. We found that two different blood cell lineages, the plasmatocyte and lamellocyte lineages, contribute to the generation of lamellocytes in a demand-adapted hematopoietic process. Plasmatocytes transdifferentiate into lamellocyte-like cells in situ directly on the wasp egg. In parallel, a novel population of infection-induced cells, which we named lamelloblasts, appears in the circulation. Lamelloblasts proliferate vigorously and develop into the major class of circulating lamellocytes. Our data indicate that lamellocyte differentiation upon wasp parasitism is a plastic and dynamic process. Flow cytometry with in vivo hemocyte reporters can be used to study this phenomenon in detail. PMID:27414410

Transdifferentiation and Proliferation in Two Distinct Hemocyte Lineages in Drosophila melanogaster Larvae after Wasp Infection.

PubMed

Anderl, Ines; Vesala, Laura; Ihalainen, Teemu O; Vanha-Aho, Leena-Maija; Andó, István; Rämet, Mika; Hultmark, Dan

2016-07-01

Cellular immune responses require the generation and recruitment of diverse blood cell types that recognize and kill pathogens. In Drosophila melanogaster larvae, immune-inducible lamellocytes participate in recognizing and killing parasitoid wasp eggs. However, the sequence of events required for lamellocyte generation remains controversial. To study the cellular immune system, we developed a flow cytometry approach using in vivo reporters for lamellocytes as well as for plasmatocytes, the main hemocyte type in healthy larvae. We found that two different blood cell lineages, the plasmatocyte and lamellocyte lineages, contribute to the generation of lamellocytes in a demand-adapted hematopoietic process. Plasmatocytes transdifferentiate into lamellocyte-like cells in situ directly on the wasp egg. In parallel, a novel population of infection-induced cells, which we named lamelloblasts, appears in the circulation. Lamelloblasts proliferate vigorously and develop into the major class of circulating lamellocytes. Our data indicate that lamellocyte differentiation upon wasp parasitism is a plastic and dynamic process. Flow cytometry with in vivo hemocyte reporters can be used to study this phenomenon in detail.

Subtyping Salmonella enterica serovar enteritidis isolates from different sources by using sequence typing based on virulence genes and clustered regularly interspaced short palindromic repeats (CRISPRs).

PubMed

Liu, Fenyun; Kariyawasam, Subhashinie; Jayarao, Bhushan M; Barrangou, Rodolphe; Gerner-Smidt, Peter; Ribot, Efrain M; Knabel, Stephen J; Dudley, Edward G

2011-07-01

Salmonella enterica subsp. enterica serovar Enteritidis is a major cause of food-borne salmonellosis in the United States. Two major food vehicles for S. Enteritidis are contaminated eggs and chicken meat. Improved subtyping methods are needed to accurately track specific strains of S. Enteritidis related to human salmonellosis throughout the chicken and egg food system. A sequence typing scheme based on virulence genes (fimH and sseL) and clustered regularly interspaced short palindromic repeats (CRISPRs)-CRISPR-including multi-virulence-locus sequence typing (designated CRISPR-MVLST)-was used to characterize 35 human clinical isolates, 46 chicken isolates, 24 egg isolates, and 63 hen house environment isolates of S. Enteritidis. A total of 27 sequence types (STs) were identified among the 167 isolates. CRISPR-MVLST identified three persistent and predominate STs circulating among U.S. human clinical isolates and chicken, egg, and hen house environmental isolates in Pennsylvania, and an ST that was found only in eggs and humans. It also identified a potential environment-specific sequence type. Moreover, cluster analysis based on fimH and sseL identified a number of clusters, of which several were found in more than one outbreak, as well as 11 singletons. Further research is needed to determine if CRISPR-MVLST might help identify the ecological origins of S. Enteritidis strains that contaminate chickens and eggs.

Infection with Paragonimus westermani of boar-hunting dogs in Western Japan maintained via artificial feeding with wild boar meat by hunters.

PubMed

Irie, Takao; Yamaguchi, Yohei; Doanh, Pham Ngoc; Guo, Zhi Hong; Habe, Shigehisa; Horii, Yoichiro; Nonaka, Nariaki

2017-08-18

Infection of boar-hunting dogs with Paragonimus westermani was investigated in Western Japan. Blood and rectal feces were collected from 441 dogs in the three districts (205 in Kinki, 131 in Chugoku and 105 in Shikoku District). In a screening ELISA for serum antibody against P. westermani antigen, 195 dogs (44.2%) showed positive reaction. In the 195 dogs, 8 dogs were found excreting P. westermani eggs after molecular analysis of fecal eggs, and additional 7 were identified serologically for the parasite infection because of their stronger reactivity against P. westermani antigen than against antigens of other species of Paragonimus. A spatial analysis showed that all of the P. westermani infections were found in Kinki and Chugoku Districts. In this area, dogs' experience of being fed with raw boar meat showed high odds ratio (3.35) to the sero-positivity in the screening ELISA, and the frequency of such experiences was significantly higher in sero-positive dogs. While clear relationship was not obtained between predation of boars by dogs during hunting and their sero-positivity. Therefore, it is suggested that human activity of feeding with wild boar meat is the risk factor for P. westermani infection in boar-hunting dogs. Considering that hunting dogs could play as a major definitive host and maintain the present distribution of P. westermani in Western Japan, control measures for the infection in hunting dogs, such as prohibition of raw meat feeding and regular deworming, should be undertaken.

Species-Specific Serological Detection for Schistosomiasis by Serine Protease Inhibitor (SERPIN) in Multiplex Assay.

PubMed

Tanigawa, Chihiro; Fujii, Yoshito; Miura, Masashi; Nzou, Samson Muuo; Mwangi, Anne Wanjiru; Nagi, Sachiyo; Hamano, Shinjiro; Njenga, Sammy M; Mbanefo, Evaristus Chibunna; Hirayama, Kenji; Mwau, Matilu; Kaneko, Satoshi

2015-01-01

Both Schistosoma mansoni and Schistosoma haematobium cause schistosomiasis in sub-Saharan Africa. We assessed the diagnostic value of selected Schistosoma antigens for the development of a multiplex serological immunoassay for sero-epidemiological surveillance. Diagnostic ability of recombinant antigens from S. mansoni and S. haematobium was assessed by Luminex multiplex immunoassay using plasma from school children in two areas of Kenya, endemic for different species of schistosomiasis. S. mansoni serine protease inhibitor (SERPIN) and Sm-RP26 showed significantly higher reactivity to patient plasma as compared to the control group. Sm-Filamin, Sm-GAPDH, Sm-GST, Sm-LAP1, Sm-LAP2, Sm-Sm31, Sm-Sm32 and Sm-Tropomyosin did not show difference in reactivity between S. mansoni infected and uninfected pupils. Sm-RP26 was cross-reactive to plasma from S. haematobium patients, whereas Sm-SERPIN was species-specific. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. ROC analysis for Sm-RP26, Sm-SERPIN and Sh-SERPIN showed AUC values of 0.833, 0.888 and 0.947, respectively. Using Spearman's rank correlation coefficient analysis, we also found significant positive correlation between the number of excreted eggs and median fluorescence intensity (MFI) from the multiplex immunoassays for Sm-SERPIN (ρ = 0.430, p-value = 0.003) and Sh-SERPIN (ρ = 0.433, p-value = 0.006). Sm-SERPIN is a promising species-specific diagnostic antigen. Sh-SEPRIN was partially cross-reactive to S. mansoni infected patients. SERPINs showed correlation with the number of excreted eggs. These indicate prospects for inclusion of SERPINs in the multiplex serological immunoassay system.

Identification, sequence analysis, and characterization of serine/threonine protein kinase 17A from Clonorchis sinensis.

PubMed

Huang, Lisi; Lv, Xiaoli; Huang, Yan; Hu, Yue; Yan, Haiyan; Zheng, Minghui; Zeng, Hua; Li, Xuerong; Liang, Chi; Wu, Zhongdao; Yu, Xinbing

2014-05-01

This is the first report of a novel protein from Clonorchis sinensis (C. sinensis), serine/threonine protein kinase 17A (CsSTK17A), which belongs to a member of the death-associated protein kinase (DAPK) family known to regulate diverse biological processes. The full-length sequence encoding CsSTK17A was isolated from C. sinensis adult cDNA plasmid library. Two transcribed isoforms of the gene were identified from the genome of C. sinensis. CsSTK17A contains a kinase domain at the N-terminus that shares a degree of conservation with the DAPK families. Besides, the catalytic domain contains 11 subdomains conserved among STKs and shares the highest identity with STK from Schistosoma mansoni (55.9%). Three-dimensional structure of CsSTK17A displays the canonical STK fold, including the helix C, P-loop, and the activation loop. We obtained recombinant CsSTK17A (rCsSTK17A) and anti-rCsSTK17A IgG. The rCsSTK17A could be probed by anti-rCsSTK17A rat serum, C. sinensis-infected rat serum and the sera from rats immunized with C. sinensis excretory-secretory products, indicating that it is a circulating antigen possessing a strong immunocompetence. Moreover, quantitative RT-PCR and western blotting analyses revealed that CsSTK17A exhibited the highest mRNA and protein expression level in eggs, followed by metacercariae and adult worms. Intriguingly, in the immunolocalization assay, CsSTK17A was intensively localized to the operculum region of eggs in uterus, as well as the vitelline gland of both adult worm and metacercaria, implying that the protein was associated with the reproduction and development of C. sinensis. Overall, these fundamental studies might contribute to further researches on signaling systems of the parasite.

Circulating gluten-specific FOXP3+CD39+ regulatory T cells have impaired suppressive function in patients with celiac disease.

PubMed

Cook, Laura; Munier, C Mee Ling; Seddiki, Nabila; van Bockel, David; Ontiveros, Noé; Hardy, Melinda Y; Gillies, Jana K; Levings, Megan K; Reid, Hugh H; Petersen, Jan; Rossjohn, Jamie; Anderson, Robert P; Zaunders, John J; Tye-Din, Jason A; Kelleher, Anthony D

2017-12-01

Celiac disease is a chronic immune-mediated inflammatory disorder of the gut triggered by dietary gluten. Although the effector T-cell response in patients with celiac disease has been well characterized, the role of regulatory T (Treg) cells in the loss of tolerance to gluten remains poorly understood. We sought to define whether patients with celiac disease have a dysfunction or lack of gluten-specific forkhead box protein 3 (FOXP3) + Treg cells. Treated patients with celiac disease underwent oral wheat challenge to stimulate recirculation of gluten-specific T cells. Peripheral blood was collected before and after challenge. To comprehensively measure the gluten-specific CD4 + T-cell response, we paired traditional IFN-γ ELISpot with an assay to detect antigen-specific CD4 + T cells that does not rely on tetramers, antigen-stimulated cytokine production, or proliferation but rather on antigen-induced coexpression of CD25 and OX40 (CD134). Numbers of circulating gluten-specific Treg cells and effector T cells both increased significantly after oral wheat challenge, peaking at day 6. Surprisingly, we found that approximately 80% of the ex vivo circulating gluten-specific CD4 + T cells were FOXP3 + CD39 + Treg cells, which reside within the pool of memory CD4 + CD25 + CD127 low CD45RO + Treg cells. Although we observed normal suppressive function in peripheral polyclonal Treg cells from patients with celiac disease, after a short in vitro expansion, the gluten-specific FOXP3 + CD39 + Treg cells exhibited significantly reduced suppressive function compared with polyclonal Treg cells. This study provides the first estimation of FOXP3 + CD39 + Treg cell frequency within circulating gluten-specific CD4 + T cells after oral gluten challenge of patients with celiac disease. FOXP3 + CD39 + Treg cells comprised a major proportion of all circulating gluten-specific CD4 + T cells but had impaired suppressive function, indicating that Treg cell dysfunction might be a key contributor to disease pathogenesis. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Oral peptide specific egg antibody to intestinal sodium-dependent phosphate co-transporter-2b is effective at altering phosphate transport in vitro and in vivo.

PubMed

Bobeck, Elizabeth A; Hellestad, Erica M; Sand, Jordan M; Piccione, Michelle L; Bishop, Jeff W; Helvig, Christian; Petkovich, Martin; Cook, Mark E

2015-06-01

Hyperimmunized hens are an effective means of generating large quantities of antigen specific egg antibodies that have use as oral supplements. In this study, we attempted to create a peptide specific antibody that produced outcomes similar to those of the human pharmaceutical, sevelamer HCl, used in the treatment of hyperphosphatemia (a sequela of chronic renal disease). Egg antibodies were generated against 8 different human intestinal sodium-dependent phosphate cotransporter 2b (NaPi2b) peptides, and hNaPi2b peptide egg antibodies were screened for their ability to inhibit phosphate transport in human intestinal Caco-2 cell line. Antibody produced against human peptide sequence TSPSLCWT (anti-h16) was specific for its peptide sequence, and significantly reduced phosphate transport in human Caco-2 cells to 25.3±11.5% of control nonspecific antibody, when compared to nicotinamide, a known inhibitor of phosphate transport (P≤0.05). Antibody was then produced against the mouse-specific peptide h16 counterpart (mouse sequence TSPSYCWT, anti-m16) for further analysis in a murine model. When anti-m16 was fed to mice (1% of diet as dried egg yolk powder), egg yolk immunoglobulin (IgY) was detected using immunohistochemical staining in mouse ileum, and egg anti-m16 IgY colocalized with a commercial goat anti-NaPi2b antibody. The effectiveness of anti-m16 egg antibody in reducing serum phosphate, when compared to sevelamer HCl, was determined in a mouse feeding study. Serum phosphate was reduced 18% (P<0.02) in mice fed anti-m16 (1% as dried egg yolk powder) and 30% (P<0.0001) in mice fed sevelamer HCl (1% of diet) when compared to mice fed nonspecific egg immunoglobulin. The methods described and the findings reported show that oral egg antibodies are useful and easy to prepare reagents for the study and possible treatment of select diseases. © 2015 Poultry Science Association Inc.

Divergent genetic evolution of hemagglutinin in influenza A H1N1 and A H1N2 subtypes isolated in the south-France since the winter of 2001-2002.

PubMed

Al Faress, Shaker; Cartet, Gaëlle; Ferraris, Olivier; Norder, Helene; Valette, Martine; Lina, Bruno

2005-07-01

Influenza A viruses are divided into subtypes based on their hemagglutinin (H1 to H15) and neuraminidase (N1 to N9) glycoproteins. Of these, three A subtypes H1N1, H3N2 and H1N2 circulate in the human population. Influenza A viruses display a high antigenic variability called "antigenic drift" which allows the virus to escape antibody neutralization. Evaluate the mutations apparition that might predict a divergent antigenic evolution of hemagglutinin in influenza A H1N1 and A H1N2 viruses. During the three winters of 2001-2002 to 2003-2004, 58 A H1N1 and 23 A H1N2 subtypes have been isolated from patients with influenza-like illness in the south of France. The HA1 region was analyzed by RT-PCR and subsequently sequenced to compare the HA1 genetic evolution of influenza A H1N1 and A H1N2 subtypes. Our results showed that 28 amino acid substitutions have accumulated in the HA1 region since the circulation of A/New Caledonia/20/99-like viruses in France. Of these, fifteen were located in four antigenic sites (B, C, D and E). Six of them were observed only in the A H1N2 isolates, six only in the A H1N1 isolates and three in both subtypes. Furthermore, nine of twenty two A H1N2 isolates from the winter of 2002-2003 shared a T90A amino acid change which has not been observed in any A H1N1 isolate; resulting in the introduction of a new glycosylation site close to the antigenic site E. This might mask some antigenic E determinants and therefore, modify the A H1N2 antigenicity. The divergent genetic evolution of hemagglutinin may ultimately lead to a significant different antigenicity between A H1N1 and A H1N2 subtypes that would require the introduction of a new subtype in the vaccine batches.

Detection of Circulating Paracoccidioides brasiliensis Antigen in Urine of Paracoccidioidomycosis Patients before and during Treatment

PubMed Central

Salina, Margarete Aparecida; Shikanai-Yasuda, Maria Aparecida; Mendes, Rinaldo Poncio; Barraviera, Benedito; Mendes Giannini, Maria José Soares

1998-01-01

For the diagnosis and follow-up of paracoccidioidomycosis patients undergoing therapy, we evaluated two methods (immunoblotting and competition enzyme immunoassay) for the detection of circulating antigen in urine samples. A complex pattern of reactivity was observed in the immunoblot test. Bands of 70 and 43 kDa were detected more often in urine samples from patients before treatment. The immunoblot method detected gp43 and gp70 separately or concurrently in 11 (91.7%) of 12 patients, whereas the competition enzyme immunoassay detected antigenuria in 9 (75%) of 12 patients. Both tests appeared to be highly specific (100%), considering that neither fraction detectable by immunoblotting was present in urine samples from the control group. gp43 remained present in the urine samples collected during the treatment period, with a significant decrease in reactivity in samples collected during clinical recovery and increased reactivity in samples collected during relapses. Reactivity of some bands was also detected in urine specimens from patients with “apparent cure.” The detection of Paracoccidioides brasiliensis antigens in urine appears to be a promising method for diagnosing infection, for evaluating the efficacy of treatment, and for detecting relapse. PMID:9620407

Coral snake antivenom produced in chickens (Gallus domesticus).

PubMed

Aguilar, Irma; Sánchez, Elda E; Girón, María E; Estrella, Amalid; Guerrero, Belsy; Rodriguez-Acosta, F Alexis

2014-01-01

The production of anti-snake venom from large mammal's blood has been found to be low-yielding and arduous, consequently, antivenom immunoglobulins for treatment are achieved regularly as polyvalent serum. We have standardized an undemanding technique for making purified immunoglobulin IgY antivenom consisting of polyclonal antibodies against coral snake venom in the egg yolk of immunized hens. We have adapted a reported process of antibody purification from egg yolks, and achieved 90% antibody purity. The customized technique consisted of the removal of lipids from distilled water-diluted egg yolks by a freeze-thaw sequence. The specific immunoglobulins were present in the egg yolk for up to 180 days postimmunization. Therefore, by means of small venom quantities, a significant amount of immunoglobulins were found in an adequately purified state (The obtained material contained about 90% pure IgY). The antigen binding of the immunoglobulins was detected by a double immunodiffusion test. Titers of antibodies in the yolk were estimated with a serum protection assay (Median effective dose = ED50) (ED50= 477 mg/kg). Given that breeding hens is economically feasible, egg gathering is noninvasive and the purification of IgY antibodies is quick and easy, chicken immunization is an excellent alternative for the production of polyclonal antibodies. To the best of our knowledge, this is the first coral snake antivenom prepared in birds.

CORAL SNAKE ANTIVENOM PRODUCED IN CHICKENS (Gallus domesticus)

PubMed Central

Aguilar, Irma; Sánchez, Elda E.; Girón, María E.; Estrella, Amalid; Guerrero, Belsy; Rodriguez-Acosta, F. Alexis

2014-01-01

The production of anti-snake venom from large mammal's blood has been found to be low-yielding and arduous, consequently, antivenom immunoglobulins for treatment are achieved regularly as polyvalent serum. We have standardized an undemanding technique for making purified immunoglobulin IgY antivenom consisting of polyclonal antibodies against coral snake venom in the egg yolk of immunized hens. We have adapted a reported process of antibody purification from egg yolks, and achieved 90% antibody purity. The customized technique consisted of the removal of lipids from distilled water-diluted egg yolks by a freeze–thaw sequence. The specific immunoglobulins were present in the egg yolk for up to 180 days postimmunization. Therefore, by means of small venom quantities, a significant amount of immunoglobulins were found in an adequately purified state (The obtained material contained about 90% pure IgY). The antigen binding of the immunoglobulins was detected by a double immunodiffusion test. Titers of antibodies in the yolk were estimated with a serum protection assay (Median effective dose = ED50) (ED50= 477 mg/kg). Given that breeding hens is economically feasible, egg gathering is noninvasive and the purification of IgY antibodies is quick and easy, chicken immunization is an excellent alternative for the production of polyclonal antibodies. To the best of our knowledge, this is the first coral snake antivenom prepared in birds. PMID:24553610

Loss of endothelial barrier antigen immunoreactivity as a marker of Clostridium perfringens type D epsilon toxin-induced microvascular damage in rat brain.

PubMed

Finnie, J W; Manavis, J; Chidlow, G

2014-01-01

The epsilon toxin elaborated by Clostridium perfringens type D in the intestine of domestic livestock is principally responsible for the neurological disease produced after its absorption in excessive quantities into the systemic circulation. The fundamental basis of the cerebral damage induced by epsilon toxin appears to be microvascular injury with ensuing severe, diffuse vasogenic oedema. Endothelial barrier antigen (EBA), which is normally expressed by virtually all capillaries and venules in the rat brain, was used in this study as a marker of blood-brain barrier (BBB) integrity. After exposure to high levels of circulating epsilon toxin, there was substantial loss of EBA in many brain microvessels, attended by widespread plasma albumin extravasation. These results support microvascular injury and subsequent BBB breakdown as a key factor in the pathogenesis of epsilon toxin-induced neurological disease. Copyright © 2014 Elsevier Ltd. All rights reserved.

Antigen-Specific lgA B Memory Cell Responses to Shigella Antigens Elicited in Volunteers Immunized with Live Attenuated Shigella flexneri 2a Oral Vaccine Candidates

DTIC Science & Technology

2011-01-01

parenterally (e.g. small· pox vaccine [33]) and orally (e.g., rotavirus vaccines [34]) and parenteral conjugate vaccines consisting of bacterial polysacchar...Angel, Evaluation of circulating intestinally committed memory B cells in children vaccinated with attenuated human rotavirus vaccine, Viral lmmunol...Soler, E. C. Butcher, D. Bass, J. Angel, M.A. Franco, H.B. Greenberg, Maturation and trafficking markers on rotavirus -specific B cells during

Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on intensity of infection and antibody responses to schistosome antigens: results of a randomised, placebo-controlled trial

PubMed Central

2009-01-01

Background Praziquantel treatment of schistosomiasis during pregnancy was only recommended in 2002; hence the effects of treatment during pregnancy are not fully known. We have therefore evaluated the effects on infection intensity and the immunological effects of praziquantel treatment against Schistosoma mansoni during pregnancy, compared with treatment after delivery. Methods A nested cohort of 387 Schistosoma mansoni infected women was recruited within a larger trial of de-worming during pregnancy. Women were randomised to receive praziquantel or placebo during pregnancy. All women were treated after delivery. Infection intensity after treatment was assessed by a single Kato-Katz examination of stool samples with duplicate slides and categorised as undetected, light (1–99 eggs per gram (epg)), moderate (100–399 epg) or heavy (≥400 epg). Antibodies against S. mansoni worm and egg antigens were measured by ELISA. Results were compared between women first treated during pregnancy and women first treated after delivery. Results At enrolment, 252 (65.1%) of the women had light infection (median (IQR) epg: 35 (11, 59)), 75 (19.3%) moderate (median (IQR) epg: 179(131, 227)) and 60 (15.5%) had heavy infection (median (IQR) epg: 749 (521, 1169)) with S. mansoni. At six weeks after praziquantel treatment during pregnancy S. mansoni infection was not detectable in 81.9% of the women and prevalence and intensity had decreased to 11.8% light, 4.7% moderate and 1.6% heavy a similar reduction when compared with those first treated after delivery (undetected (88.5%), light (10.6%), moderate (0.9%) and heavy (0%), p = 0.16). Parasite specific antibody levels were lower during pregnancy than after delivery. Praziquantel treatment during pregnancy boosted anti-worm IgG isotypes and to a lesser extent IgE, but these boosts were less pronounced than in women whose treatment was delayed until after delivery. Praziquantel had limited effects on antibodies against egg antigens. Conclusion S mansoni antigen-specific antibody levels and praziquantel-induced boosts in antibody levels were broadly suppressed during pregnancy, but this was not associated with major reduction in the efficacy of praziquantel. Long-term implications of these findings in relation to resistance to re-infection remain to be explored. Trial registration International Standard Randomised Controlled Trial Number for the current study: ISRCTN32849447 http://www.controlled-trials.com/ISRCTN32849447/elliott PMID:19296834

[Humoral immune diseases: Cutaneous vasculitis and auto-immune bullous dermatoses].

PubMed

Wechsler, Janine

2018-02-01

Humoral immunity is the cause of multiple diseases related to antibodies (IgA, IgG, IgM) produced by the patient. Two groups of diseases are identified. The first group is related to circulating antigen-antibody complexes. The antigens are various. They are often unknown. These immune complexes cause a vascular inflammation due to the complement fixation. Consequently, this group is dominated by inflammatory vasculitis. In the second group, the pathology is due to the fixation in situ of antibodies to a target antigen of the skin that is no more recognized by the patient. This group is represented by the auto-immune bullous dermatoses. Copyright © 2017. Published by Elsevier Masson SAS.

PATHOGENETIC MECHANISMS IN EXPERIMENTAL IMMUNE FEVER

PubMed Central

Root, Richard K.; Wolff, Sheldon M.

1968-01-01

When rabbits sensitized to human serum albumin (HSA) are challenged intravenously with specific antigen, fever develops and two transferable pyrogens can be demonstrated in the circulation. The first appears prior to the development of fever and has properties consistent with soluble antigen-antibody complexes. These have been shown to be pyrogenic when prepared in vitro and to produce a state of febrile tolerance when repeatedly administered. The second pyrogen, demonstrable during fever in donor rabbits, appears to be similar to endogenous pyrogen described in other experimental fevers. It is postulated that the formation of antigen-antibody complexes constitutes an important initial phase of the febrile reaction in this type of immune fever. PMID:4873023

Circulating rotavirus-specific T cells have a poor functional profile.

PubMed

Parra, Miguel; Herrera, Daniel; Jácome, María Fernanda; Mesa, Martha C; Rodríguez, Luz-Stella; Guzmán, Carolina; Angel, Juana; Franco, Manuel A

2014-11-01

Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ(+) cells, while influenza-CD4 and tetanus toxoid-CD4 T cell responses were enriched in multifunctional T cells. Moreover, rIL-2--unlike rIL-12 or DGKα-i--increased the frequencies of RV-CD4 TNF-α(+), CD4 IFN-γ(+), and CD8 IFN-γ(+) cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. Copyright © 2014 Elsevier Inc. All rights reserved.

Molecular Epidemiology and Antigenic Characterization of Seasonal Influenza Viruses Circulating in Nepal.

PubMed

Upadhyay, B P; Ghimire, P; Tashiro, M; Banjara, M R

2017-01-01

Influenza is one of the public health burdens in Nepal and its epidemiology is not clearly understood. The objective of this study was to explore the molecular epidemiology and the antigenic characteristics of the circulating influenza viruses in Nepal. A total of 1495 throat swab specimens were collected from January to December, 2014. Real time PCR assay was used for identification of influenza virus types and subtypes. Ten percent of the positive specimens were randomly selected and inoculated onto Madin-Darby Canine Kidney Epithelial cells (MDCK) for influenza virus isolation. All viruses were characterized by the hemagglutination inhibition (HI) assay. Influenza viruses were detected in 421/1495 (28.2%) specimens. Among positive cases, influenza A virus was detected in 301/421 (71.5%); of which 120 (39.9%) were influenza A/H1N1 pdm09 and 181 (60.1%) were influenza A/H3 subtype. Influenza B viruses were detected in 119/421 (28.3%) specimens. Influenza A/H1N1 pdm09, A/H3 and B viruses isolated in Nepal were antigenically similar to the vaccine strain influenza A/California/07/2009(H1N1pdm09), A/Texas/50/2012(H3N2), A/New York/39/2012(H3N2) and B/Massachusetts/2/2012, respectively. Influenza viruses were reported year-round in different geographical regions of Nepal which was similar to other tropical countries. The circulating influenza virus type and subtypes of Nepal were similar to vaccine candidate virus which could be prevented by currently used influenza vaccine.

Circulation of the rabies virus in non-hematophagous bats in the city of Rio de Janeiro, Brazil, during 2001-2010.

PubMed

Cabral, Claudius Couto; Morais, Ana Carolina Nunes de; Dias, Alba Valéria de Almeida Barcelos; Araújo, Marcela Garcia; Moreira, Wildeberg Cal; Mattos, Gláucio Luis Mata

2012-01-01

Rabies is one of the most known lethal zoonosis, responsible for 55,000 human deaths per year. It is transmitted to humans mainly by the bite of domestic or wild animals infected with the virus. This paper shows the circulation of this virus in non-hematophagous bats in the City of Rio de Janeiro, Brazil. A survey was performed on the number of bats that had been sent for diagnosis by the Seção de Virologia of the Instituto Municipal de Medicina Veterinária Jorge Vaitsman and were positive for rabies. The positive animals were identified, and the isolated viruses were sent for antigenic typification with indirect immunofluorescence. The results were compared with the antigenic panel of the Centers for Disease Control and Prevention. During 2001-2010, the laboratory received 555 non-hematophagous bats for rabies diagnosis, with 198 (35.7%) from Rio de Janeiro City. A total of 11 (5.5%) animals were positive for this disease. Antigenic typification revealed the predominance of variant 3 in 9 (81.8%) of the isolated viruses; 1 virus was classified as variant 4 and 1 variant was identified that segregated with the viruses in insectivorous bats. The data obtained in this study showed the presence of the rabies virus in synanthropic populations of non-hematophagous bats in the City of Rio de Janeiro. The circulation of this agent in these animals represents a serious risk to human and animal health and requires attention and control measures by the authorities.

Factors Regulating Early Life History Dispersal of Atlantic Cod (Gadus morhua) from Coastal Newfoundland

PubMed Central

Stanley, Ryan R. E.; deYoung, Brad; Snelgrove, Paul V. R.; Gregory, Robert S.

2013-01-01

To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day−1 with a net mortality of 27%•day–1. Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10–20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic. PMID:24058707

Costs of counterdefenses to host resistance in a parasitoid of Drosophila.

PubMed

Kraaijeveld, A R; Hutcheson, K A; Limentani, E C; Godfray, H C

2001-09-01

The ability of a parasitoid to evolve enhanced counterdefenses against host resistance and its possible costs were studied in a Drosophila-parasitoid system. We reared Asobara tabida (Braconidae, Hymenoptera) exclusively on D. melanogaster to impose artificial selection for improved counterdefenses against cellular encapsulation, the main host defense against parasitism. Controls were reared on D. subobscura, the main host of the population of wasps from which the laboratory culture was derived and a species that never encapsulates parasitoids. We observed improved survival and avoidance of encapsulation in all five selection lines compared to their paired control lines, although there was unexpected variation among pairs. Improved survival was associated with parasitoid eggs becoming embedded in host tissue, where they were protected from circulating haemocytes. There were no differences among lines in average adult size, fat content, egg load, or performance on D. subobscura. However, the duration of the egg stage in selection lines was longer than that of control lines, probably because of reduced nutrient and/or oxygen supply when eggs are embedded in host tissue. We suggest that this delay in hatching reduces the probability of parasitoid survival if another parasitoid egg is laid in the same host (superparasitism or multiparasitism) and hence is a cost of enhanced counterdefenses against host resistance.

PERSISTENCE OF HAPTEN-ANTIBODY COMPLEXES IN THE CIRCULATION OF IMMUNIZED ANIMALS AFTER A SINGLE INTRAVENOUS INJECTION OF HAPTEN

PubMed Central

Schmidt, Donald H.; Kaufman, Bette M.; Butler, Vincent P.

1974-01-01

To study the fate of a low molecular weight antigen (hapten) in the circulation of animals whose sera contain antibodies specific for that low molecular weight antigen, a single injection of digoxin-3H (0.4 mg/kg) was administered intravenously to 18 rabbits. Thirteen animals (nine nonimmunized and four immunized with bovine serum albumin) served as control animals. In five rabbits which had been immunized with a digoxin-bovine serum albumin conjugate and whose sera contained digoxin-specific antibodies, the mean 12-h serum digoxin concentration was 8,300 ng/ml (control: 92 ng/ml) and the mean serum concentration 12 mo after the single injection of digoxin-3H was 85 ng/ml. In digoxin-immunized rabbits, less than 10% of the digoxin-3H was excreted in the first 10 days (control: 77% recovered in urine and feces) and the mean biological half-life of digoxin, as calculated from serum digoxin-3H disappearance curves, was 72 days (control: 3.4 days). In sera of digoxin-immunized rabbits, more than 90% of the circulating digoxin-3H was immunoglobulin bound, as determined by the double-antibody and dextran-coated charcoal methods. The serum disappearance rate of 125I-antidigoxin antibodies was similar in nonimmunized and in immunized animals and in the presence or absence of digoxin. It is concluded that the biological half-life of a hapten may be markedly prolonged when the hapten is bound to specific antibody. The persistence of antibody-hapten complexes in the circulation suggests that these complexes may not be deposited in tissues and raises the possibility that low molecular weight determinants may be capable of preventing or reversing the deposition of immune complexes, containing macromolecular antigens, in the tissues of experimental animals and man. PMID:4129823

Comparative evaluation of the diagnostic potential of recombinant envelope proteins and native cell culture purified viral antigens of Chikungunya virus.

PubMed

Khan, Mohsin; Dhanwani, Rekha; Kumar, Jyoti S; Rao, P V Lakshmana; Parida, Manmohan

2014-07-01

Despite the fact that Chikungunya resurgence is associated with epidemic of unprecedented magnitude, there are challenges in the field of its clinical diagnosis. However, serological tests in an ELISA format provide a rapid tool for the diagnosis of Chikungunya infection. Indeed, ELISAs based on recombinant proteins hold a great promise as these methods are cost effective and are free from the risk of handling biohazardous material. In this study, the performance of recombinant CHIKV antigens was compared in various ELISA formats for the diagnosis of Chikungunya. Two recombinant antigens derived from the envelope proteins of Chikungunya virus were prepared and evaluated by comparing their competence for detecting circulating antibodies in serum samples of patients infected with CHIKV using MAC-ELISA and indirect IgM-ELISA. The efficacy of the recombinant antigens was also compared with the native antigen. The indirect antibody capture IgM microplate ELISA revealed ≥90% concordance with the native antigen in detecting the CHIKV specific IgM antibodies whereas the recombinant antigen based MAC-ELISA showed 100% specificity. The recombinant antigens used in this study were effective and reliable targets for the diagnosis of CHIKV infection and also provide an alternative for native antigen use which is potentially biohazardous. © 2013 Wiley Periodicals, Inc.

Characterization of the carbohydrate components of Taenia solium oncosphere proteins and their role in the antigenicity.

PubMed

Arana, Yanina; Verastegui, Manuela; Tuero, Iskra; Grandjean, Louis; Garcia, Hector H; Gilman, Robert H

2013-10-01

This study examines the carbohydrate composition of Taenia solium whole oncosphere antigens (WOAs), in order to improve the understanding of the antigenicity of the T. solium. Better knowledge of oncosphere antigens is crucial to accurately diagnose previous exposure to T. solium eggs and thus predict the development of neurocysticercosis. A set of seven lectins conjugates with wide carbohydrate specificity were used on parasite fixations and somatic extracts. Lectin fluorescence revealed that D-mannose, D-glucose, D-galactose and N-acetyl-D-galactosamine residues were the most abundant constituents of carbohydrate chains on the surface of T. solium oncosphere. Lectin blotting showed that posttranslational modification with N-glycosylation was abundant while little evidence of O-linked carbohydrates was observed. Chemical oxidation and enzymatic deglycosylation in situ were performed to investigate the immunoreactivity of the carbohydrate moieties. Linearizing or removing the carbohydrate moieties from the protein backbones did not diminish the immunoreactivity of these antigens, suggesting that a substantial part of the host immune response against T. solium oncosphere is directed against the peptide epitopes on the parasite antigens. Finally, using carbohydrate probes, we demonstrated for the first time that the presence of several lectins on the surface of the oncosphere was specific to carbohydrates found in intestinal mucus, suggesting a possible role in initial attachment of the parasite to host cells.

CHARACTERIZATION OF THE CARBOHYDRATE COMPONENTS OF Taenia solium ONCOSPHERE PROTEINS AND THEIR ROLE IN THE ANTIGENICITY

PubMed Central

Arana, Yanina; Verastegui, Manuela; Tuero, Iskra; Grandjean, Louis; Garcia, Hector H.; Gilman, Robert H.

2015-01-01

This study examines the carbohydrate composition of Taenia solium whole oncosphere antigens (WOAs), in order to improve the understanding of the antigenicity of the T. solium. Better knowledge of oncosphere antigens is crucial to accurately diagnose previous exposure to T. solium eggs and thus predict the development of neurocysticercosis. A set of seven lectins conjugates with wide carbohydrate specificity were used on parasite fixations and somatic extracts. Lectin fluorescence revealed that D-mannose, D-glucose, D-galactose and N-acetyl-D-galactosamine residues were the most abundant constituents of carbohydrate chains on the surface of T. solium oncosphere. Lectin blotting showed that post-translational modification with N-glycosylation was abundant while little evidence of O-linked carbohydrates was observed. Chemical oxidation and enzymatic deglycosylation in situ were performed to investigate the immunoreactivity of the carbohydrate moieties. Linearizing or removing the carbohydrate moieties from the protein backbones did not diminish the immunoreactivity of these antigens, suggesting that a substantial part of the host immune response against T. solium oncosphere is directed against the peptide epitopes on the parasite antigens. Finally, using carbohydrate probes, we demonstrated for the first time that the presence of several lectins on the surface of the oncosphere was specific to carbohydrates found in intestinal mucus, suggesting a possible role in initial attachment of the parasite to host cells. PMID:23982308

[Establishment of A1E3 and B1C4 monoclonal antibody-based ELISA for detecting circulating antigen of Schistosoma japonicum and its preliminary application].

PubMed

Cai, Yu-Chun; Chen, Shao-Hong; Tian, Li-Guang; Chu, Yan-Hong; Lu, Yan; Chen, Mu-Xin; Ai, Lin; Zhou, Yang; Chen, Jia-Xu

2014-02-01

To establish A1E3 and B1C4 monoclonal antibody-based ELISA for detecting circulating antigen of Schistosoma japonicum and explore its application value in the field. The characteristics of A1E3 and B1C4 monoclonal antibodies were analyzed by SDS-PAGE and Western blotting. The SEA-based ELISA was used to evaluate the titers of A1E3 and B1C4. The orthogonal test was used to determine the best concentration of coating antibody B1C4 and optimal working concentration of A1E3-HRP. Under the optimal conditions, the serum samples of 20 acute schistosomiasis cases, 46 chronic schistosomiasis cases, and 20 control sera were tested to evaluate its detection sensitivity and specificity. Seventy-two antibody positive serum samples from Jiangling County of Hubei Province were detected and compared to a commercially available ELISA kit, to evaluate the detection effects of this method. The results of SDS-PAGE demonstrated that the purified A1E3 and B1C4 contained a clear heavy chain with molecular weight of 88,000 and 52,000 respectively and had the same light chain with molecular weight of 20,000; while Western blotting demonstrated that A1E3 and B1C4 could be recognized by SEA and serum samples of acute schistosomiasis cases. The SEA-based ELISA demonstrated the titers of B1C4 and A1E3 were 1:10(5) and 1:30,000, respectively. The serum samples from all the acute cases and 86.9% of the chronic cases showed a positive reaction. All of the control sera from healthy persons gave a negative response. The positive rates of the double monoclonal antibody ELISA and commercial ELISA for detecting the circulating antigen were 45.8% and 43.1% respectively, and there was no significant difference between the results of the two methods. A1E3 and B1C4 monoclonal antibody-based ELISA is established successfully. It exhibits a high sensitivity and specificity in detecting circulating antigen of Schistosoma japonicum.

Dynamic Convergent Evolution Drives the Passage Adaptation across 48 Years' History of H3N2 Influenza Evolution.

PubMed

Chen, Hui; Deng, Qiang; Ng, Sock Hoon; Lee, Raphael Tze Chuen; Maurer-Stroh, Sebastian; Zhai, Weiwei

2016-12-01

Influenza viruses are often propagated in a diverse set of culturing media and additional substitutions known as passage adaptation can cause extra evolution in the target strain, leading to ineffective vaccines. Using 25,482 H3N2 HA1 sequences curated from Global Initiative on Sharing All Influenza Data and National Center for Biotechnology Information databases, we found that passage adaptation is a very dynamic process that changes over time and evolves in a seesaw like pattern. After crossing the species boundary from bird to human in 1968, the influenza H3N2 virus evolves to be better adapted to the human environment and passaging them in embryonated eggs (i.e., an avian environment) leads to increasingly stronger positive selection. On the contrary, passage adaptation to the mammalian cell lines changes from positive selection to negative selection. Using two statistical tests, we identified 19 codon positions around the receptor binding domain strongly contributing to passage adaptation in the embryonated egg. These sites show strong convergent evolution and overlap extensively with positively selected sites identified in humans, suggesting that passage adaptation can confound many of the earlier studies on influenza evolution. Interestingly, passage adaptation in recent years seems to target a few codon positions in antigenic surface epitopes, which makes it difficult to produce antigenically unaltered vaccines using embryonic eggs. Our study outlines another interesting scenario whereby both convergent and adaptive evolution are working in synchrony driving viral adaptation. Future studies from sequence analysis to vaccine production need to take careful consideration of passage adaptation. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Physicochemical properties of anti Vibrio harveyi egg yolk antibody (IgY) and its immunological influence in Indian white shrimp Fenneropenaeus indicus.

PubMed

Kumaran, Thankamani; Thirumalaikumar, Eswaramoorthy; Lelin, Chinnadurai; Palanikumar, Pandi; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

2018-03-01

Edible antibodies specific to host pathogens is an attractive approach to establish protective immunity, especially against gastrointestinal pathogens both in humans and animals. The edible antibody of anti-Vibrio harveyi IgY (anti-V. h IgY) was produced by antigen mixed with immunoadjuvant Asparagus racemosus and Glycine max. Hens were immunized and eggs were collected five weeks after the immunization. Anti-V. harveyi IgY stability in different digestive enzymes such as trypsin and chymotrypsin were evaluated to determine its ability to withstand in the gastrointestinal tract of F. indicus. Specific binding activity and concentration (average 9.5% of total IgY content) of the anti-V. h IgY were determined by the ELISA using V. harveyi antigen. Further the anti-V. h IgY diets including V.h wo, V.h A, V.h G and control diets were fed to F. indicus for 60 days. After 30 and 60 of feeding, group of shrimps were challenged with virulent V. harveyi. After the respective days of feeding, haematological and immunological changes were studied. The parameters including total haemocyte count (THC), coagulase activity, oxyhaemocyanin level, prophenoloxidase, intracellular superoxide anion production, lysozyme, phagocytosis and bacterial agglutinin had significantly (P ≤ .001) increased in the experimental groups in comparission with the control diet fed shrimps. The anti-V. h IgY coated diets helped to reduce the Vibrio load and boosted the immune system in F. indicus's against V. harveyi challenge. The research work shows the potential applications of egg yolk antibodies as anti-bacterial prophylactic uses for infectious diseases and suggests an edible antibody concept as an alternative to conventional antibiotics. Copyright © 2018 Elsevier Ltd. All rights reserved.

Exosomes Derived from Dendritic Cells Treated with Schistosoma japonicum Soluble Egg Antigen Attenuate DSS-Induced Colitis

PubMed Central

Wang, Lifu; Yu, Zilong; Wan, Shuo; Wu, Feng; Chen, Wei; Zhang, Beibei; Lin, Datao; Liu, Jiahua; Xie, Hui; Sun, Xi; Wu, Zhongdao

2017-01-01

Exosomes are 30–150 nm small membrane vesicles that are released into the extracellular medium via cells that function as a mode of intercellular communication. Dendritic cell (DC)-derived exosomes modulate immune responses and prevent the development of autoimmune diseases. Moreover, Schistosoma japonicum eggs show modulatory effects in a mouse model of colitis. Therefore, we hypothesized that exosomes derived from DCs treated with S. japonicum soluble eggs antigen (SEA; SEA-treated DC exosomes) would be useful for treating inflammatory bowel disease (IBD). Exosomes were purified from the supernatant of DCs treated or untreated with SEA and identified via transmission electron microscopy, western blotting and NanoSight. Acute colitis was induced via the administration of dextran sulfate sodium (DSS) in drinking water (5.0%, wt/vol). Treatment with exosomes was conducted via intraperitoneal injection (i.p.; 50 μg per mouse) from day 0 to day 6. Clinical scores were calculated based on weight loss, stool type, and bleeding. Colon length was measured as an indirect marker of inflammation, and colon macroscopic characteristics were determined. Body weight loss and the disease activity index of DSS-induced colitis mice decreased significantly following treatment with SEA-treated DC exosomes. Moreover, the colon lengths of SEA-treated DC exosomes treated colitis mice improved, and their mean colon macroscopic scores decreased. In addition, histologic examinations and histological scores showed that SEA-treated DC exosomes prevented colon damage in acute DSS-induced colitis mice. These results indicate that SEA-treated DC exosomes attenuate the severity of acute DSS-induced colitis mice more effectively than DC exosomes. The current work suggests that SEA-treated DC exosomes may be useful as a new approach to treat IBD. PMID:28959207

Immunotherapy Plus Cryotherapy: Potential Augmented Abscopal Effect for Advanced Cancers

PubMed Central

Abdo, Joe; Cornell, David L.; Mittal, Sumeet K.; Agrawal, Devendra K.

2018-01-01

Since the 1920s the gold standard for treating cancer has been surgery, which is typically preceded or followed with chemotherapy and/or radiation, a process that perhaps contributes to the destruction of a patient’s immune defense system. Cryosurgery ablation of a solid tumor is mechanistically similar to a vaccination where hundreds of unique antigens from a heterogeneous population of tumor cells derived from the invading cancer are released. However, releasing tumor-derived self-antigens into circulation may not be sufficient enough to overcome the checkpoint escape mechanisms some cancers have evolved to avoid immune responses. The potentiated immune response caused by blocking tumor checkpoints designed to prevent programmed cell death may be the optimal treatment method for the immune system to recognize these new circulating cryoablated self-antigens. Preclinical and clinical evidence exists for the complementary roles for Cytotoxic T-lymphocyte-associated protein (CTLA-4) and PD-1 antagonists in regulating adaptive immunity, demonstrating that combination immunotherapy followed by cryosurgery provides a more targeted immune response to distant lesions, a phenomenon known as the abscopal effect. We propose that when the host’s immune system has been “primed” with combined anti-CTLA-4 and anti-PD-1 adjuvants prior to cryosurgery, the preserved cryoablated tumor antigens will be presented and processed by the host’s immune system resulting in a robust cytotoxic CD8+ T-cell response. Based on recent investigations and well-described biochemical mechanisms presented herein, a polyvalent autoinoculation of many tumor-specific antigens, derived from a heterogeneous population of tumor cancer cells, would present to an unhindered yet pre-sensitized immune system yielding a superior advantage in locating, recognizing, and destroying tumor cells throughout the body. PMID:29644213

Novel reassortant H9N2 viruses in pigeons and evidence for antigenic diversity of H9N2 viruses isolated from quails in Egypt.

PubMed

Kandeil, Ahmed; El-Shesheny, Rabeh; Maatouq, Asmaa; Moatasim, Yassmin; Cai, Zhipeng; McKenzie, Pamela; Webby, Richard; Kayali, Ghazi; Ali, Mohamed A

2017-04-01

The endemicity of avian influenza viruses (AIVs) among Egyptian poultry represents a public health risk. Co-circulation of low pathogenic AIV H9N2 subtype with highly pathogenic AIV H5N1 subtype in Egyptian farms provides a possibility to generate novel reassortant viruses. Here, the genetic characteristics of surface glycoproteins of 59 Egyptian H9N2 viruses, isolated between 2013 and 2015, were analysed. To elucidate the potential of genetic reassortment, 10 H9N2 isolates were selected based on different avian hosts (chickens, ducks, pigeons and quails) and phylogenetic analyses of their full genome sequences were conducted. Additionally, we performed antigenic analysis to further investigate the antigenic evolution of H9N2 viruses isolated during 2011-2015. Different viral characteristics including receptor-binding affinity and drug resistance of representative Egyptian H9N2 viruses were further investigated. The surface glycoproteins of current Egyptian H9N2 viruses were closely related to viruses of the G1-like lineage isolated from Egypt. Several genetic markers that enhance virulence in poultry and transmission to humans were detected. Analysis of the full genome of 10 H9N2 isolates indicated that two pigeon isolates inherited five internal genes from Eurasian AIVs circulating in wild birds. Antigenic conservation of different Egyptian H9N2 isolates from chickens, pigeons and ducks was observed, whereas quail isolates showed antigenic drift. The Egyptian H9N2 viruses preferentially bound to the human-like receptor rather than to the avian-like receptor. Our results suggest that the endemic H9N2 viruses in Egypt contain elements that may favour avian-to-human transmission and thus represent a public health risk.

Prediction and characterization of novel epitopes of serotype A foot-and-mouth disease viruses circulating in East Africa using site-directed mutagenesis

PubMed Central

Bari, Fufa Dawo; Parida, Satya; Asfor, Amin S.; Haydon, Daniel T.; Reeve, Richard; Paton, David J.

2015-01-01

Epitopes on the surface of the foot-and-mouth disease virus (FMDV) capsid have been identified by monoclonal antibody (mAb) escape mutant studies leading to the designation of four antigenic sites in serotype A FMDV. Previous work focused on viruses isolated mainly from Asia, Europe and Latin America. In this study we report on the prediction of epitopes in African serotype A FMDVs and testing of selected epitopes using reverse genetics. Twenty-four capsid amino acid residues were predicted to be of antigenic significance by analysing the capsid sequences (n = 56) using in silico methods, and six residues by correlating capsid sequence with serum–virus neutralization data. The predicted residues were distributed on the surface-exposed capsid regions, VP1–VP3. The significance of residue changes at eight of the predicted epitopes was tested by site-directed mutagenesis using a cDNA clone resulting in the generation of 12 mutant viruses involving seven sites. The effect of the amino acid substitutions on the antigenic nature of the virus was assessed by virus neutralization (VN) test. Mutations at four different positions, namely VP1-43, VP1-45, VP2-191 and VP3-132, led to significant reduction in VN titre (P value = 0.05, 0.05, 0.001 and 0.05, respectively). This is the first time, to our knowledge, that the antigenic regions encompassing amino acids VP1-43 to -45 (equivalent to antigenic site 3 in serotype O), VP2-191 and VP3-132 have been predicted as epitopes and evaluated serologically for serotype A FMDVs. This identifies novel capsid epitopes of recently circulating serotype A FMDVs in East Africa. PMID:25614587

Intramuscular Therapeutic Vaccination Targeting HPV16 Induces T Cell Responses That Localize in Mucosal Lesions

PubMed Central

Jotova, Iveta; Wu, T. C.; Wang, Chenguang; Desmarais, Cindy; Boyer, Jean D.; Tycko, Benjamin; Robins, Harlan S.; Clark, Rachael A.; Trimble, Cornelia L.

2014-01-01

About 25% of high-grade cervical intraepithelial neoplasias (CIN2/3) caused by human papillomavirus serotype 16 (HPV16) undergo complete spontaneous regression. However, to date, therapeutic vaccination strategies for HPV disease have yielded limited success when measured by their ability to induce robust peripheral blood T cell responses to vaccine antigen. We report marked immunologic changes in the target lesion microenvironment after intramuscular therapeutic vaccination targeting HPV16 E6/E7 antigens, in subjects with CIN2/3 who had modest detectable responses in circulating T lymphocytes. Histologic and molecular changes, including markedly (average threefold) increased intensity of CD8+ T cell infiltrates in both the stromal and epithelial compartments, suggest an effector response to vaccination. Postvaccination cervical tissue immune infiltrates included organized tertiary lymphoid-like structures in the stroma subjacent to residual intraepithelial lesions and, unlike infiltrates in unvaccinated lesions, showed evidence of proliferation induced by recognition of cognate antigen. At a molecular level, these histologic changes in the stroma were characterized by increased expression of genes associated with immune activation (CXCR3) and effector function (Tbet and IFNβ), and were also associated with an immunologic signature in the overlying dysplastic epithelium. High-throughput T cell receptor sequencing of unmanipulated specimens identified clonal expansions in the tissue that were not readily detectable in peripheral blood. Together, these findings indicate that peripheral therapeutic vaccination to HPV antigens can induce a robust tissue-localized effector immune response, and that analyses of immune responses at sites of antigen are likely to be much more informative than analyses of cells that remain in the circulation. PMID:24477000

Whole-genome sequencing and antigenic analysis of the first equine influenza virus identified in Turkey.

PubMed

Gahan, Jacinta; Garvey, Marie; Gildea, Sarah; Gür, Emre; Kagankaya, Anil; Cullinane, Ann

2018-05-01

In 2013, there was an outbreak of acute respiratory disease in racehorses in Turkey. The clinical signs were consistent with equine influenza (EI). The aim was to confirm the cause of the outbreak and characterise the causal virus. A pan-reactive influenza type A real-time RT-PCR and a rapid antigen detection kit were used for confirmatory diagnosis of equine influenza virus (EIV). Immunological susceptibility to EIV was examined using single radial haemolysis and ELISA. Antigenic characterisation was completed by haemagglutinin inhibition using a panel of specific ferret antisera. Genetic characterisation was achieved by whole-genome sequencing using segment-specific primers with M13 tags. A H3N8 EIV of the Florida clade 2 sublineage (FC2) was confirmed as the causal agent. The index cases were unvaccinated and immunologically susceptible. Phylogenetic analysis of the HA1 and NA genes demonstrated that A/equine/Ankara/1/2013 clustered with the FC2 strains circulating in Europe. Antigenic characterisation confirmed the FC2 classification and demonstrated the absence of significant drift. Whole-genome sequencing indicated that A/equine/Ankara/1/2013 is most closely related to the viruses described as the 179 group based on the substitution I179V in HA1, for example A/equine/East Renfrewshire/2/2011, A/equine/Cambremer/1/2012 and A/equine/Saone et Loire/1/2015. The greatest diversity was observed in the NS1 segment and the polymerase complex. The first recorded outbreak of EI in Turkey was caused by an FC2 virus closely related to viruses circulating in Europe. Antigenic and genetic characterisation gave no indication that the current OIE recommendations for EI vaccine composition require modification. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

Environmental proxies of antigen exposure explain variation in immune investment better than indices of pace of life.

PubMed

Horrocks, Nicholas P C; Hegemann, Arne; Ostrowski, Stéphane; Ndithia, Henry; Shobrak, Mohammed; Williams, Joseph B; Matson, Kevin D; Tieleman, B I

2015-01-01

Investment in immune defences is predicted to covary with a variety of ecologically and evolutionarily relevant axes, with pace of life and environmental antigen exposure being two examples. These axes may themselves covary directly or inversely, and such relationships can lead to conflicting predictions regarding immune investment. If pace of life shapes immune investment then, following life history theory, slow-living, arid zone and tropical species should invest more in immunity than fast-living temperate species. Alternatively, if antigen exposure drives immune investment, then species in antigen-rich tropical and temperate environments are predicted to exhibit higher immune indices than species from antigen-poor arid locations. To test these contrasting predictions we investigated how variation in pace of life and antigen exposure influence immune investment in related lark species (Alaudidae) with differing life histories and predicted risks of exposure to environmental microbes and parasites. We used clutch size and total number of eggs laid per year as indicators of pace of life, and aridity, and the climatic variables that influence aridity, as correlates of antigen abundance. We quantified immune investment by measuring four indices of innate immunity. Pace of life explained little of the variation in immune investment, and only one immune measure correlated significantly with pace of life, but not in the predicted direction. Conversely, aridity, our proxy for environmental antigen exposure, was predictive of immune investment, and larks in more mesic environments had higher immune indices than those living in arid, low-risk locations. Our study suggests that abiotic environmental variables with strong ties to environmental antigen exposure can be important correlates of immunological variation.

Vaccination of sheep against haemonchosis with H11, a gut membrane-derived protective antigen from the adult parasite: prevention of the periparturient rise and colostral transfer of protective immunity.

PubMed

Andrews, S J; Hole, N J; Munn, E A; Rolph, T P

1995-07-01

Pregnant ewes were immunised with a fraction highly enriched in the membrane glycoprotein antigen H11, isolated from the intestinal brush border of adult Haemonchus contortus. Immunity induced by immunisation was able to abolish almost completely (98-99%) the worm egg output from pregnant ewes challenged with ca. 10,000 infective larvae of H. contortus during the last trimester. Furthermore, lambs born and reared on vaccinated ewes had substantial antibody levels to H11 derived from maternal transfer. This antibody conferred moderate protection against a bolus challenge of ca. 3000 infective larvae of H. contortus in 5-week-old lambs.

Do intestinal parasites interfere with the seroepidemiologic surveillance of Schistosoma mansoni infection?

PubMed Central

Alarcón de Noya, B.; Colmenares, C.; Losada, S.; Fermin, Z.; Masroua, G.; Ruiz, L.; Soto, L.; Noya, O.

1996-01-01

In view of the known cross-reactivity of sera from patients with intestinal parasites to some Schistosoma mansoni antigens, field work was conducted in an area of Venezuela non-endemic for schistosomiasis using the routine immunoenzymatic assay (ELISA) with soluble egg antigen (SEA). False positive reactions represented 15.3% of the total population as determined by SEA-ELISA. SEA-immunoblotting of the false positive sera indicated that protein fractions of 91 and 80 kDa appear to be responsible for cross-reactivity. Sera from hookworm infected individuals produced a higher frequency and intensity of cross-reaction than other sera. SEA-fractions of 105, 54, 46, 42, 32, 25 and 15 kDa were the most specific. Images Fig. 2 PMID:8666077

Production, characterization and applications for Toxoplasma gondii-specific polyclonal chicken egg yolk immunoglobulins.

PubMed

Ferreira Júnior, Álvaro; Santiago, Fernanda M; Silva, Murilo V; Ferreira, Flávia B; Macêdo Júnior, Arlindo G; Mota, Caroline M; Faria, Matheus S; Silva Filho, Hercílio H; Silva, Deise A O; Cunha-Júnior, Jair P; Mineo, José R; Mineo, Tiago W P

2012-01-01

Toxoplasma gondii may cause abortions, ocular and neurological disorders in warm-blood hosts. Immunized mammals are a wide source of hyperimmune sera used in different approaches, including diagnosis and the study of host-parasite interactions. Unfortunately, mammalian antibodies present limitations for its production, such as the necessity for animal bleeding, low yield, interference with rheumatoid factor, complement activation and affinity to Fc mammalian receptors. IgY antibodies avoid those limitations; therefore they could be an alternative to be applied in T. gondii model. In this study we immunized hens with soluble tachyzoite antigens of T. gondii (STAg) and purified egg yolk antibodies (IgY) by an inexpensive and simple method, with high yield and purity degree. IgY anti-STAg antibodies presented high avidity and were able to recognize a broad range of parasite antigens, although some marked differences were observed in reactivity profile between antibodies produced in immunized hens and mice. Interestingly, IgY antibodies against Neospora caninum and Eimeria spp. did not react to STAg. We also show that IgY antibodies were suitable to detect T. gondii forms in paraffin-embedded sections and culture cell monolayers. Due to its cost-effectiveness, high production yield and varied range of possible applications, polyclonal IgY antibodies are useful tools for studies involving T. gondii.

Stabilized filter-supported bilayer lipid membranes (BLMs) for automated flow monitoring of compounds of clinical, pharmaceutical, environmental and industrial interest

PubMed Central

Siontorou, Christina G.

1997-01-01

This paper describes the results of analytical applications of electrochemical biosensors based on bilayer lipid membranes (BLMs) for the automated rapid and sensitive flow monitoring of substrates of hydrolytic enzymes, antigens and triazine herbicides. BLMs, composed of mixtures of egg phosphatidylcholine (egg PC) and dipalmitoylphosphatidic acid (DPPA), were supported on ultrafiltration membranes (glass microfibre or polycarbonate filters) which were found to enhance their stability for flow experiments. The proteins (enzymes, antibodies) were incorporated into a floating lipid matrix at an air-electrolyte interface, and then a casting procedure was used to deliver the lipid onto the filter supports for BLM formation. Injections of the analyte were made into flowing streams of the carrier electrolyte solution and a current transient signal was obtained with a magnitude related to the analyte concentration. Substrates of hydrolytic enzyme reactions (acetylcholine, urea and penicillin) could be determined at the micromolar level with a maximum rate of 220 samples/h, whereas antigens (thyroxin) and triazine herbicides (simazine, atrazine and propazine) could be monitored at the nanomolar level in less than 2 min. The time of appearance of the transient response obtained for herbicides was increased to the order of simazine, atrazine and propazine which has permitted analysis of these triazines in mixtures. PMID:18924789

FluBlok, a next generation influenza vaccine manufactured in insect cells.

PubMed

Cox, Manon M J; Hollister, Jason R

2009-06-01

FluBlok, a recombinant trivalent hemagglutinin (rHA) vaccine produced in insect cell culture using the baculovirus expression system, provides an attractive alternative to the current egg-based trivalent inactivated influenza vaccine (TIV). Its manufacturing process presents the possibility for safe and expeditious vaccine production. FluBlok contains three times more HA than TIV and does not contain egg-protein or preservatives. The high purity of the antigen enables administration at higher doses without a significant increase in side-effects in human subjects. The insect cell-baculovirus production technology is particularly suitable for influenza where annual adjustment of the vaccine is required. The baculovirus-insect expression system is generally considered a safe production system, with limited growth potential for adventitious agents. Still regulators question and challenge the safety of this novel cell substrate as FluBlok continues to advance toward product approval. This review provides an overview of cell substrate characterization for expresSF cell line used for the manufacturing of FluBlok. In addition, this review includes an update on the clinical development of FluBlok. The highly purified protein vaccine, administered at three times higher antigen content than TIV, is well tolerated and results in stronger immunogenicity, a long lasting immune response and provides cross-protection against drift influenza viruses.

Routinely used immunoassays do not detect circulating anti-GBM antibodies against native NC1 hexamer and EA epitope of the α3 chain of type IV collagen.

PubMed

Clavarino, Giovanna; Gauthier, Arnaud; Hellmark, Thomas; Carron, Pierre-Louis; Giovannini, Diane; Colliard, Sophie; Dragon-Durey, Marie-Agnès; Segelmark, Mårten; Cesbron, Jean-Yves; Dumestre-Pérard, Chantal

2018-04-12

Detection of circulating anti-GBM antibodies has a key role for the diagnosis of Goodpasture syndrome but immunoassays using purified or recombinant alpha3(IV)NC1 as antigen do not recognize all anti-GBM antibodies. We show that anti-GBM antibodies directed against epitopes in their native conformation or cryptic epitopes are detected by indirect immunofluorescence. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermodynamics of antibody-antigen interaction revealed by mutation analysis of antibody variable regions.

PubMed

Akiba, Hiroki; Tsumoto, Kouhei

2015-07-01

Antibodies (immunoglobulins) bind specific molecules (i.e. antigens) with high affinity and specificity. In order to understand their mechanisms of recognition, interaction analysis based on thermodynamic and kinetic parameters, as well as structure determination is crucial. In this review, we focus on mutational analysis which gives information about the role of each amino acid residue in antibody-antigen interaction. Taking anti-hen egg lysozyme antibodies and several anti-small molecule antibodies, the energetic contribution of hot-spot and non-hot-spot residues is discussed in terms of thermodynamics. Here, thermodynamics of the contribution from aromatic, charged and hydrogen bond-forming amino acids are discussed, and their different characteristics have been elucidated. The information gives fundamental understanding of the antibody-antigen interaction. Furthermore, the consequences of antibody engineering are analysed from thermodynamic viewpoints: humanization to reduce immunogenicity and rational design to improve affinity. Amino acid residues outside hot-spots in the interface play important roles in these cases, and thus thermodynamic and kinetic parameters give much information about the antigen recognition. Thermodynamic analysis of mutant antibodies thus should lead to advanced strategies to design and select antibodies with high affinity. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

The effects of a deleterious mutation load on patterns of influenza A/H3N2's antigenic evolution in humans

PubMed Central

Koelle, Katia; Rasmussen, David A

2015-01-01

Recent phylogenetic analyses indicate that RNA virus populations carry a significant deleterious mutation load. This mutation load has the potential to shape patterns of adaptive evolution via genetic linkage to beneficial mutations. Here, we examine the effect of deleterious mutations on patterns of influenza A subtype H3N2's antigenic evolution in humans. By first analyzing simple models of influenza that incorporate a mutation load, we show that deleterious mutations, as expected, act to slow the virus's rate of antigenic evolution, while making it more punctuated in nature. These models further predict three distinct molecular pathways by which antigenic cluster transitions occur, and we find phylogenetic patterns consistent with each of these pathways in influenza virus sequences. Simulations of a more complex phylodynamic model further indicate that antigenic mutations act in concert with deleterious mutations to reproduce influenza's spindly hemagglutinin phylogeny, co-circulation of antigenic variants, and high annual attack rates. DOI: http://dx.doi.org/10.7554/eLife.07361.001 PMID:26371556

Genotype distribution of norovirus around the emergence of Sydney_2012 and the antigenic drift of contemporary GII.4 epidemic strains.

PubMed

Zhang, Jun; Shen, Zhen; Zhu, Zhaoqin; Zhang, Wanju; Chen, Huifen; Qian, Fangxing; Chen, Haili; Wang, Gang; Wang, Moying; Hu, Yunwen; Yuan, Zhenghong

2015-11-01

The pattern of epochal evolution of NoV is ongoing, while novel GII.4 variants emerge and cause new pandemics. Since, the emergence in March 2012, Sydney_2012 had replaced GII.4-2009 as the primary NoV strain in most countries in the northern hemisphere by November 2012. To determine the genotype distribution around the emergence of Sydney_2012 and to investigate the underlying evolution mechanisms of the contemporary GII.4 strains. From January 2012 to December 2013, molecular epidemiology of norovirus in 846 adults (≥16 years) in Shanghai were conducted. The VP1 proteins of the contemporary GII.4 strains (Den_Haag_2006b, New_Orleans_2009 and Sydney_2012) were expressed in vitro and purified. Receptor binding patterns of these three epidemic strains were determined through histo-blood group antigen (HBGA) binding assays. Convalescent serum from patients infected with GII.4 epidemic strains were employed to investigate the role of antigenic drift in the persistence of GII.4 epidemic strains through receptor-binding blockade assays. Epidemiological studies revealed that Sydeny_2012 has completely replaced Den_Haag_2006b and New_Orleans_2009 and has been the dominant circulating strain in Shanghai since its emergence in October 2012. Interestingly, Den_Haag_2006b and New_Orleans_2009 have been co-circulating in Shanghai before the emergence of Sydeny_2012. The contemporary GII.4 epidemic norovirus strains displayed commonly high tropism to the histo-blood group antigen receptors, whereas Sydeny_2012 was antigenically different from Den_Haag_2006b and New_Orleans_2009. Antigenic drift, rather than receptor switch, played a key role in the emergence and spreading of Sydney_2012. The contemporary GII.4 strains were evolving via epochal evolution without altered ligand binding profiles. Copyright © 2015 Elsevier B.V. All rights reserved.

Schistosome-derived omega-1 drives Th2 polarization by suppressing protein synthesis following internalization by the mannose receptor

PubMed Central

Everts, Bart; Hussaarts, Leonie; Driessen, Nicole N.; Meevissen, Moniek H.J.; Schramm, Gabriele; van der Ham, Alwin J.; van der Hoeven, Barbara; Scholzen, Thomas; Burgdorf, Sven; Mohrs, Markus; Pearce, Edward J.; Hokke, Cornelis H.; Haas, Helmut; Smits, Hermelijn H.

2012-01-01

Omega-1, a glycosylated T2 ribonuclease (RNase) secreted by Schistosoma mansoni eggs and abundantly present in soluble egg antigen, has recently been shown to condition dendritic cells (DCs) to prime Th2 responses. However, the molecular mechanisms underlying this effect remain unknown. We show in this study by site-directed mutagenesis of omega-1 that both the glycosylation and the RNase activity are essential to condition DCs for Th2 polarization. Mechanistically, we demonstrate that omega-1 is bound and internalized via its glycans by the mannose receptor (MR) and subsequently impairs protein synthesis by degrading both ribosomal and messenger RNA. These experiments reveal an unrecognized pathway involving MR and interference with protein synthesis that conditions DCs for Th2 priming. PMID:22966004

[Antigens (CEA and CA 19-9) in diagnosis and prognosis colorectal cancer].

PubMed

Grotowski, Maciej

2002-01-01

carcinoembryonic antigen (CEA) was first described more than three decades ago, when its presence was demonstrated in fetal gut tissue and in tumors from gastrointestinal tract. Subsequently, CEA was detected in the circulation of patients and recognized as a serum marker for colorectal cancer. This tumor marker has not been advocated as a screening test for colorectal cancer, however a preoperative CEA serum level is useful for diagnosis and prognosis of recurrence and survival in colorectal cancer patients. The levels of CEA increased with increasing tumor stage. Expression of carbohydrate antigen (CA 19-9) has been described in various malignancies and also in colorectal cancer. This antigen also has not been advocated as a screening test for colorectal cancer. The levels of CA 19-9 increased in advanced stages of colorectal cancer. Despite its lower sensitivity than CEA in early stages of colorectal cancer, the combination of both antigens can provided more information than CEA alone for prognosis of recurrence and survival in those patients.

[Production, specificity and structure of immunoglobulins].

PubMed

Goujard, C; Delfraissy, J F

1991-03-21

Immunoglobulin is a key factor of the immune response resulting from B-cell activation and associated with T-cell stimulation. Because of its structure, this antibody has a dual function: it specifically recognizes the inducer antigen in the variable region and eliminates it by a constant portion which is responsible for effector properties. Surface immunoglobulin, therefore, is the B-cell antigen receptor; it differs from the T-cell receptor in that it recognizes the antigen unbound to the major istocompatibility complex; binding the antigen results in direct signal transduction first in the cytoplasm, then in the nucleus. This receptor can be secreted in the body: it is made up of circulating immunoglobulins. Human immunoglobulins are divided into 5 classes, each of them with its own response kinetics, distribution and functions. The variability of the antibody response accounts for a genetic organization involving numerous genes which may be associated with each other, or mutate, or recombine during maturation of the lymphocytes. Altogether, this system has a theoretical capacity of response to three hundred million different antigens.

Surveillance of intestinal schistosomiasis during control: a comparison of four diagnostic tests across five Ugandan primary schools in the Lake Albert region.

PubMed

Al-Shehri, Hajri; Koukounari, Artemis; Stanton, Michelle C; Adriko, Moses; Arinaitwe, Moses; Atuhaire, Aaron; Kabatereine, Narcis B; Stothard, J Russell

2018-03-21

Programmatic surveillance of intestinal schistosomiasis during control can typically use four diagnostic tests, either singularly or in combination, but these have yet to be cross-compared directly. Our study assembled a complete diagnostic dataset, inclusive of infection intensities, from 258 children from five Ugandan primary schools. The schools were purposely selected as typical of the endemic landscape near Lake Albert and reflective of high- and low-transmission settings. Overall prevalence was: 44.1% (95% CI 38.0-50.2) by microscopy of duplicate Kato-Katz smears from two consecutive stools, 56.9% (95% CI 50.8-63.0) by urine-circulating cathodic antigen (CCA) dipstick, 67.4% (95% CI 61.6-73.1) by DNA-TaqMan® and 75.1% (95% CI 69.8-80.4) by soluble egg antigen enzyme-linked immunosorbent assay (SEA-ELISA). A cross-comparison of diagnostic sensitivities, specificities, positive and negative predictive values was undertaken, inclusive of a latent class analysis (LCA) with a LCA-model estimate of prevalence by each school. The latter ranged from 9.6% to 100.0%, and prevalence by school for each diagnostic test followed a static ascending order or monotonic series of Kato-Katz, urine-CCA dipstick, DNA-TaqMan® and SEA-ELISA. We confirm that Kato-Katz remains a satisfactory diagnostic standalone in high-transmission settings but in low-transmission settings should be augmented or replaced by urine-CCA dipsticks. DNA-TaqMan® appears suitable in both endemic settings though is only implementable if resources permit. In low-transmission settings, SEA-ELISA remains the method of choice to evidence an absence infection. We discuss the pros and cons of each method concluding that future surveillance of intestinal schistosomiasis would benefit from a flexible, context-specific approach both in choice and application of each diagnostic method, rather than a single one-size fits all approach.

Histological study of cell migration in the dermis of hamsters after immunisation with two different vaccines against visceral leishmaniasis.

PubMed

Moreira, Nádia das Dores; Giunchetti, Rodolfo Cordeiro; Carneiro, Cláudia Martins; Vitoriano-Souza, Juliana; Roatt, Bruno Mendes; Malaquias, Luiz Cosme Cotta; Corrêa-Oliveira, Rodrigo; Reis, Alexandre Barbosa

2009-04-15

Vaccine candidates, including live and/or killed parasites, Leishmania-purified fractions, defined recombinant antigens and antigen-encoding DNA-plasmids have been proposed to use as vaccine anti-Leishmania. More recently, the hamsters have been used to pre-selection of antigens candidate to apply in further experiments using canine model. In this report we evaluated the kinetics of cell migration in dermal inflammatory infiltrate, circulating leukocytes and the presence of nitric oxide (NO)/induced nitric oxide synthase during the early (1-24h) and late (48-168h) periods following inoculation of hamsters with antigenic components of anti-canine visceral leishmaniasis vaccines Leishmune and Leishmania braziliensis antigen (LB) with and without saponin (Sap) adjuvant. Our results show that LB caused an early reduction of lymphocytes in the dermis while Sap and LBSap triggered a late recruitment, suggesting the role of the adjuvant in the traffic of antigen-presenting cells and the induction of lymphocyte migration. In that manner our results suggest that the kinetics of cell migration on hamster model may be of value in the selection of vaccine antigens prior the tests in dogs particularly in respect of the toxicity of the preparations.

Decreased egg production in laying hens associated with infection with genotype 3 avian hepatitis E virus strain from China.

PubMed

Zhao, Qin; Liu, Baoyuan; Sun, Yani; Du, Taofeng; Chen, Yiyang; Wang, Xinjie; Li, Huixia; Nan, Yuchen; Zhang, Gaiping; Zhou, En-Min

2017-05-01

To determine the relationship between decreased egg production and avian HEV infection, thirty healthy 23-week-old Hy-Line Variety Brown layer hens were randomly divided into 3 groups with 10 hens per group. Next, a genotype 3 avian HEV strain from China was used to inoculate laying hens via oronasal or intravenous routes using a 50% chicken infectious dose of 500. All hens were necropsied at 14 weeks postinoculation (wpi). Fecal virus shedding, viremia, seroconversion, serum alanine aminotransferase (ALT) increases and liver lesions showed that after intravenous (i.v.) and oronasal inoculation, the laying hens were successfully infected. Compared with the uninoculated group, the i.v. and oronasally inoculated groups exhibited egg production decreases at 1wpi and 2wpi, reaching peak production at 3wpi and 8wpi, respectively. In both groups, decreased production was evident for 12 weeks and overall decreases ranged from 10% to 30%. In addition, in the 7 field layer farms exhibiting decreased egg production, vaccination regimens had been completed against Newcastle disease, infectious bronchitis, avian influenza H9N2 and H5N1 and egg drop syndrome virus. However, circulating avian HEV was confirmed on these farms using tests to detect avian HEV IgG antibodies and RNA. Therefore, the experimental and field data indicate that avian HEV infection acting alone could account for observed decreases in egg production in laying hens. Copyright © 2017 Elsevier B.V. All rights reserved.

Chandipura virus growth kinetics in vertebrate cell lines, insect cell lines & embryonated eggs.

PubMed

Jadi, R S; Sudeep, A B; Kumar, Satyendra; Arankalle, V A; Mishra, A C

2010-08-01

Since not much information on Chandipura virus is available, an attempt was made to study the growth kinetics of the virus in certain vertebrate, invertebrate cell lines and embryonated chicken eggs. Comparative study of Chandipura virus (CHPV) growth kinetics in three vertebrate cell lines [Vero E6, Rhabdo myosarcoma (RD), Porcine stable kidney (PS) cell lines], two insect cell lines [Aedes aegypti (AA) and Phlebotomus papatasi (PP-9) cell lines] and embryonated pathogen free chicken eggs was conducted, by tissue culture infective dose 50 per cent (TCID(50)) and indirect immunofluorescence assay (IFA). All the cell lines and embryonated egg supported the growth of CHPV and yielded high virus titre. The vertebrate cell lines showed distinct cytopathic effect (CPE) within 4-6 h post infection (PI), while no CPE was observed in insect cell lines. PP-9 cell line was the most sensitive system to CHPV as viral antigen could be detected at 1 h PI by IFA. Our results demonstrated that all the systems were susceptible to CHPV and achieved high yield of virus. However, the PP-9 cell line had an edge over the others due to its high sensitivity to the virus which might be useful for detection and isolation of the virus during epidemics.

Subunit influenza vaccines produced from cell culture or in embryonated chicken eggs: comparison of safety, reactogenicity, and immunogenicity.

PubMed

Reisinger, Keith S; Block, Stanley L; Izu, Allen; Groth, Nicola; Holmes, Sandra J

2009-09-15

This study assessed the safety, reactogenicity, and immunogenicity of an injectable cell culture-derived influenza vaccine (CCIV), compared with those of an injectable egg-based trivalent inactivated influenza vaccine (TIV). Adult subjects (n = 613; 18 to <50 years of age) were randomized (1:1) to receive either CCIV or TIV. The safety and reactogenicity of the 2 vaccines were assessed on the basis of solicited indicators and other adverse events (AEs) within 7 days of vaccination. All serious AEs and those AEs resulting in withdrawal were recorded throughout the study. Antibody titers were determined by the hemagglutination inhibition assay, using egg- and cell-derived antigens. Immunogenicity was assessed on the basis of the ratio of postvaccination (day 22) geometric mean titers (GMTs) between the 2 vaccines, seroprotection rates, and seroconversion rates. There was no clinically relevant difference between the safety and reactogenicity profiles of the 2 vaccines. The immunogenicity of CCIV was demonstrated to be noninferior to that of TIV on the basis of the ratio of postvaccination GMTs between the 2 vaccines. GMTs, seroprotection rates, and seroconversion rates were comparable between the 2 vaccines. The safety, reactogenicity, and immunogenicity of the CCIV and the egg-based TIV are comparable.

Expression of the hemagglutinin HA1 subunit of the equine influenza virus using a baculovirus expression system.

PubMed

Sguazza, Guillermo H; Fuentealba, Nadia A; Tizzano, Marco A; Galosi, Cecilia M; Pecoraro, Marcelo R

2013-01-01

Equine influenza virus is a leading cause of respiratory disease in horses worldwide. Disease prevention is by vaccination with inactivated whole virus vaccines. Most current influenza vaccines are generated in embryonated hens' eggs. Virions are harvested from allantoic fluid and chemically inactivated. Although this system has served well over the years, the use of eggs as the substrate for vaccine production has several well-recognized disadvantages (cost, egg supply, waste disposal and yield in eggs). The aim of this study was to evaluate a baculovirus system as a potential method for producing recombinant equine influenza hemagglutinin to be used as a vaccine. The hemagglutinin ectodomain (HA1 subunit) was cloned and expressed using a baculovirus expression vector. The expression was determined by SDS-PAGE and immunoblotting. A high yield, 20μg/ml of viral protein, was obtained from recombinant baculovirus-infected cells. The immune response in BALB/c mice was examined following rHA1 inoculation. Preliminary results show that recombinant hemagglutinin expressed from baculovirus elicits a strong antibody response in mice; therefore it could be used as an antigen for subunit vaccines and diagnostic tests. Copyright © 2013 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

Isolation of chicken embryonic stem cell and preparation of chicken chimeric model.

PubMed

Zhang, Yani; Yang, Haiyan; Zhang, Zhentao; Shi, Qingqing; Wang, Dan; Zheng, Mengmeng; Li, Bichun; Song, Jiuzhou

2013-03-01

Chicken embryonic stem cells (ESCs) were separated from blastoderms at stage-X and cultured in vitro. Alkaline phosphatase activity and stage-specific embryonic antigen-1 staining was conducted to detect ESCs. Then, chicken ESCs were transfected with linearized plasmid pEGFP-N1 in order to produce chimeric chicken. Firstly, the optimal electrotransfection condition was compared; the results showed the highest transfection efficiency was obtained when the field strength and pulse duration was 280 V and 75 μs, respectively. Secondly, the hatchability of shedding methods, drilling a window at the blunt end of egg and drilling a window at the lateral shell of egg was compared, the results showed that the hatchability was the highest for drilling a window at the lateral shell of egg. Thirdly, the hatchability of microinjection (ESCs was microinjected into chick embryo cavity) was compared too, the results showed there were significant difference between the injection group transfected with ESCs and that of other two groups. In addition, five chimeric chickens were obtained in this study and EGFP gene was expressed in some organs, but only two chimeric chicken expressed EGFP gene in the gonad, indicating that the chimeric chicken could be obtained through chick embryo cavity injection by drilling a window at the lateral shell of egg.

Femtogram Mass Biosensor Using Self-Sensing Cantilever for Allergy Check

NASA Astrophysics Data System (ADS)

Sone, Hayato; Ikeuchi, Ayumi; Izumi, Takashi; Okano, Haruki; Hosaka, Sumio

2006-03-01

A self-sensing mass biosensor with a femtogram mass sensitivity has been developed using a piezoresistive microcantilever. The mass change due to antigen and antibody adsorption on the cantilever in water was detected by the resonance frequency shift of the cantilever. We constructed a prototype harmonic vibration sensor using a commercial piezoresistive cantilever, Wheatstone bridge circuits, a positive feedback controller, an exciting piezoactuator and a phase-locked loop (PLL) demodulator. As experimental results, a mass sensitivity of about 190 fg/Hz, and a mass resolution of about 500 fg were obtained in water. The mass sensitivity is 100 times higher than that of a quartz crystal oscillation method. We demonstrated that the sensor can detect the reaction between an antibody of immunoglobulin (IgG) and an antigen of egg albumen (OVA). We confirmed that the binding ratio between the antibody and the antigen was about 1 : 2. The detection method is available for allergy check because the measured reaction ratio occurring on the cantilever concurs with the theoretical method.

Isolation and Characterization of Circulating Tumor Cells in Squamous Cell Carcinoma of the Lung Using a Non-EpCAM-Based Capture Method.

PubMed

Bozzetti, Cecilia; Quaini, Federico; Squadrilli, Anna; Tiseo, Marcello; Frati, Caterina; Lagrasta, Costanza; Azzoni, Cinzia; Bottarelli, Lorena; Galetti, Maricla; Alama, Angela; Belletti, Silvana; Gatti, Rita; Passaro, Antonio; Gradilone, Angela; Cavazzoni, Andrea; Alfieri, Roberta; Petronini, Pier Giorgio; Bonelli, Mara; Falco, Angela; Carubbi, Cecilia; Pedrazzi, Giuseppe; Nizzoli, Rita; Naldi, Nadia; Pinto, Carmine; Ardizzoni, Andrea

2015-01-01

The exclusion of circulating tumor cells (CTCs) that have lost epithelial antigens during the epithelial-to-mesenchymal transition (EMT) process by using Epithelial Cell Adhesion Molecule (EpCAM) based capture methods is still a matter of debate. In this study, cells obtained after depletion procedure from blood samples of squamous cell lung cancer (SQCLC) patients were identified based on morphology and characterized with the combination of FISH assessment and immunophenotypic profile. Five mL blood samples, collected from 55 advanced SQCLC patients, were analyzed by a non-EpCAM-based capture method. After depletion of leukocytes and erythroid cells, the negative fraction was characterized by both FISH using a fibroblast growth factor receptor 1 (FGFR1) probe and by immunocytochemistry. Thirty healthy donors were also tested. Based on morphology (nuclear dimension ≥10 μm, shape and hypercromatic aspect) suspicious circulating cells clearly distinguishable from contaminant leukocytes were observed in 49/55 (89%) SQCLC patients. Thirty-four of the 44 (77%) samples evaluable for FGFR1 FISH showed ≥ 6 FGFR1 gene copy number on average per cell. Vimentin expression involved 43% (18/42) of pooled circulating SQCLC cells, whereas only 29% (14/48) were EpCAM positive. Confocal microscopy confirmed the localization of FGFR1 probe in suspicious circulating cells. Suspicious circulating elements were also observed in healthy donors and did not show any epithelial associated antigens. A significantly lower number of suspicious circulating cells in healthy donors compared to SQCLC patients was found. Among the heterogeneous cell population isolated by depletion procedure, the coexistence of cells with epithelial and/or mesenchymal phenotype suggests that EMT may participate to transendothelial invasion and migration of tumor cells in advanced SQCLC. The finding of cells with neither EpCAM or EMT phenotype, retrieved after non-EpCAM-based systems, underlines the presence of suspicious elements in the blood of both SQCLC patients and healthy donors. Further phenotyping and molecular analyses are necessary to fully characterize these circulating elements.

Substitutions near the hemagglutinin receptor-binding site determine the antigenic evolution of influenza A H3N2 viruses in U.S. swine.

PubMed

Lewis, Nicola S; Anderson, Tavis K; Kitikoon, Pravina; Skepner, Eugene; Burke, David F; Vincent, Amy L

2014-05-01

Swine influenza A virus is an endemic and economically important pathogen in pigs, with the potential to infect other host species. The hemagglutinin (HA) protein is the primary target of protective immune responses and the major component in swine influenza A vaccines. However, as a result of antigenic drift, vaccine strains must be regularly updated to reflect currently circulating strains. Characterizing the cross-reactivity between strains in pigs and seasonal influenza virus strains in humans is also important in assessing the relative risk of interspecies transmission of viruses from one host population to the other. Hemagglutination inhibition (HI) assay data for swine and human H3N2 viruses were used with antigenic cartography to quantify the antigenic differences among H3N2 viruses isolated from pigs in the United States from 1998 to 2013 and the relative cross-reactivity between these viruses and current human seasonal influenza A virus strains. Two primary antigenic clusters were found circulating in the pig population, but with enough diversity within and between the clusters to suggest updates in vaccine strains are needed. We identified single amino acid substitutions that are likely responsible for antigenic differences between the two primary antigenic clusters and between each antigenic cluster and outliers. The antigenic distance between current seasonal influenza virus H3 strains in humans and those endemic in swine suggests that population immunity may not prevent the introduction of human viruses into pigs, and possibly vice versa, reinforcing the need to monitor and prepare for potential incursions. Influenza A virus (IAV) is an important pathogen in pigs and humans. The hemagglutinin (HA) protein is the primary target of protective immune responses and the major target of vaccines. However, vaccine strains must be updated to reflect current strains. Characterizing the differences between seasonal IAV in humans and swine IAV is important in assessing the relative risk of interspecies transmission of viruses. We found two primary antigenic clusters of H3N2 in the U.S. pig population, with enough diversity to suggest updates in swine vaccine strains are needed. We identified changes in the HA protein that are likely responsible for these differences and that may be useful in predicting when vaccines need to be updated. The difference between human H3N2 viruses and those in swine is enough that population immunity is unlikely to prevent new introductions of human IAV into pigs or vice versa, reinforcing the need to monitor and prepare for potential introductions.

Multiplexed immunophenotyping of human antigen-presenting cells in whole blood by polychromatic flow cytometry

PubMed Central

Fung, Erik; Esposito, Laura; Todd, John A.; Wicker, Linda S.

2010-01-01

We describe two modular protocols for immunostaining and multiparameter flow cytometric analysis of major human antigen-presenting cells (dendritic cells, monocytes, B lymphocytes) in minimally manipulated whole blood. Simultaneous detection of up to eight colors is enabled by careful selection and testing of cell-subset-defining monoclonal antibodies (anchor markers) in the appropriate fluorochrome combinations, to demonstrate the quantification of surface expression levels of molecules involved in chemotaxis (e.g. CX3CR1, CCR2), adhesion (e.g. CD11b, CD62L), antigen presentation (e.g. CD83, CD86, CD209) and immune regulation (e.g. CD101) on circulating antigen-presenting cells. Each immunostaining reaction requires as little as 50–100 μl of peripheral whole blood, no density-gradient separation, and the entire procedure from preparation of reagents to flow cytometry can be completed in <5 h. PMID:20134434

HCG-. beta. -subunit radioimmunoassay: potential error in HCG measurement related to choice of labeled antigen. [/sup 125/I

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tyrey, L.; Hammond, C.B.

1976-05-15

Antiserum generated against the hormone-specific ..beta..-subunit of hCG was used with different labeled antigens to measure circulating hCG in patients having trophoblastic disease. When /sup 125/I-hCG..beta.. served as the labeled antigen, a small number of patient sera failed to show parallelism with the second IS-hCG reference and erroneous estimates of hormone concentrations were obtained. Replacement of the /sup 125/I-hCG..beta.. with labeled hCG corrected the nonparallelism exhibited by these samples. Inhibition curves obtained with purified hCG and hCG..beta.. suggested that both the nonparallelism and its correction with the change in labeled antigen would be consistent with the possibility that this assaymore » aberration may result from the presence of free hCG..beta.. in these sera. (auth)« less

Antibody localization in the glomerular basement membrane may precede in situ immune deposit formation in rat glomeruli.

PubMed

Agodoa, L Y; Gauthier, V J; Mannik, M

1985-02-01

The administration of cationized antibodies, specific to human serum albumin, into the renal artery of rats caused transient presence of IgG in glomeruli by immunofluorescence microscopy. Intravenous infusion of appropriate doses of antigen after the injection of cationized antibodies resulted in immune deposit formation in glomeruli that persisted through 96 hr. By electron microscopy, these deposits were located in the subepithelial area. The injection of large doses of antigen produced immune deposits which were present in glomeruli for only a few hours, presumably due to formation of only small-latticed immune complexes. The presented data indicate that cationic antibodies bound to the fixed negative charges of the glomerular basement membrane can interact with circulating antigen to form immune deposits in glomeruli. This mechanism may be important because anionic antigens have been shown to induce the synthesis of cationic antibodies.

Universal influenza vaccines, a dream to be realized soon.

PubMed

Zhang, Han; Wang, Li; Compans, Richard W; Wang, Bao-Zhong

2014-04-29

Due to frequent viral antigenic change, current influenza vaccines need to be re-formulated annually to match the circulating strains for battling seasonal influenza epidemics. These vaccines are also ineffective in preventing occasional outbreaks of new influenza pandemic viruses. All these challenges call for the development of universal influenza vaccines capable of conferring broad cross-protection against multiple subtypes of influenza A viruses. Facilitated by the advancement in modern molecular biology, delicate antigen design becomes one of the most effective factors for fulfilling such goals. Conserved epitopes residing in virus surface proteins including influenza matrix protein 2 and the stalk domain of the hemagglutinin draw general interest for improved antigen design. The present review summarizes the recent progress in such endeavors and also covers the encouraging progress in integrated antigen/adjuvant delivery and controlled release technology that facilitate the development of an affordable universal influenza vaccine.

Population structuring of multi-copy, antigen-encoding genes in Plasmodium falciparum

PubMed Central

Artzy-Randrup, Yael; Rorick, Mary M; Day, Karen; Chen, Donald; Dobson, Andrew P; Pascual, Mercedes

2012-01-01

The coexistence of multiple independently circulating strains in pathogen populations that undergo sexual recombination is a central question of epidemiology with profound implications for control. An agent-based model is developed that extends earlier ‘strain theory’ by addressing the var gene family of Plasmodium falciparum. The model explicitly considers the extensive diversity of multi-copy genes that undergo antigenic variation via sequential, mutually exclusive expression. It tracks the dynamics of all unique var repertoires in a population of hosts, and shows that even under high levels of sexual recombination, strain competition mediated through cross-immunity structures the parasite population into a subset of coexisting dominant repertoires of var genes whose degree of antigenic overlap depends on transmission intensity. Empirical comparison of patterns of genetic variation at antigenic and neutral sites supports this role for immune selection in structuring parasite diversity. DOI: http://dx.doi.org/10.7554/eLife.00093.001 PMID:23251784

Antigen size and charge in immune complex glomerulonephritis. II. Passive induction of immune deposits with dextran-anti-dextran immune complexes.

PubMed Central

Isaacs, K. L.; Miller, F.

1983-01-01

Utilizing dextrans of restricted sizes (10,000, 70,000, 500,000 daltons), modified with regard to charge (neutral, polycationic, polyanionic) and an anti-dextran murine IgA myeloma, W3129, the authors have examined a model that may be used in the study of the combined effect of size and charge on renal deposition of immune complexes. Polycationic DEAE dextran complexes, using the 10,000 dalton antigen, showed a mesangiocapillary pattern of deposition. The other antigens showed focal to diffuse mesangial localization of varying degree. This indicates the potential usefulness of this system in examining the factors important in glomerular immune injury. The relevance to other observations, importance of polysaccharide antigens, and role in circulating versus in situ or "planted" immune complex models are considered. Images Figure 3 Figure 4 Figure 5 Figure 6 PMID:6190406

Universal Influenza Vaccines, a Dream to Be Realized Soon

PubMed Central

Zhang, Han; Wang, Li; Compans, Richard W.; Wang, Bao-Zhong

2014-01-01

Due to frequent viral antigenic change, current influenza vaccines need to be re-formulated annually to match the circulating strains for battling seasonal influenza epidemics. These vaccines are also ineffective in preventing occasional outbreaks of new influenza pandemic viruses. All these challenges call for the development of universal influenza vaccines capable of conferring broad cross-protection against multiple subtypes of influenza A viruses. Facilitated by the advancement in modern molecular biology, delicate antigen design becomes one of the most effective factors for fulfilling such goals. Conserved epitopes residing in virus surface proteins including influenza matrix protein 2 and the stalk domain of the hemagglutinin draw general interest for improved antigen design. The present review summarizes the recent progress in such endeavors and also covers the encouraging progress in integrated antigen/adjuvant delivery and controlled release technology that facilitate the development of an affordable universal influenza vaccine. PMID:24784572

Sublethal responses of avian embryos exposed to polybrominated diphenyl ether flame retardants

USGS Publications Warehouse

Rattner, B.A.; McKernan, M.A.; Ottinger, M.

2007-01-01

Polybrominated diphenyl ethers PBDEs) have been detected in bird eggs worldwide, and despite increasing concentrations over the past 25 years, toxicological thresholds have yet to be established. We previously reported embryonic survival, and pipping and hatching success in chicken (Gallus gallus), mallard (Anas platyrhynchos) and American kestrel (Falco sparverius) embryos receiving 0.01-20 :g PBDE/g egg. Survival, pipping and hatching success were decreased in kestrels, suggesting that they are more sensitive to PBDEs than chickens and mallards. Adverse effects were detected in kestrels at levels (> 1 :g/g egg) believed to approach environmentally relevant PBDE concentrations. Polychlorinated biphenyl congener 126 (PCB 126) was used as a positive control (1000 pg/g egg) in this study, and survival endpoints in chicken and kestrel were decreased at this dose. Some PBDE and PCB congeners are structurally similar to thyroid hormones and have been demonstrated to affect thyroid homeostasis in laboratory rodents. In the present study, thyroid glands collected from day old hatchling chickens, mallards, and kestrels and were analyzed for thryoxine (T4) using a solid phase radioimmunoassay (DPC, Inc.) specifically validated for each of these species. Results indicated that thyroid gland T4 stores (total gland content and T4 /mg thyroid) in these species were relatively consistent and not significantly affected by PBDE exposure. In contrast, glandular T4 stores were significantly lower (P < 0.01) in PCB 126 treated kestrels. Decreases in circulating T4 levels in response to contaminants (e.g., PCBs, ammonium perchlorate) may lead to greater release of glandular T4 to maintain a euthyroid state, which could decrease thyroidal T4 stores. While PBDEs have been suggested to influence circulating T4 in kestrel fledglings (Fernie et al., 2005), it appears that glandular T4 was not affected in chicken, mallard or kestrel hatchlings exposed in ovo. Histopathological changes in liver, kidney and immune organs, bone length, and potential skeletal deformities are currently being examined.

Effects of in-feed egg yolk antibodies on Salmonella shedding, bacterial antibiotic resistance, and health of pigs.

PubMed

Mathew, Alan G; Rattanatabtimtong, Sukanya; Nyachoti, Charles M; Fang, Lin

2009-02-01

To determine effects of anti-Salmonella egg yolk antibodies on shedding and antibiotic resistance of Salmonella enterica Typhimurium, newly weaned pigs were randomly assigned to six dietary treatments. These treatment groups were (i) a control (basal) diet without additives and similar diets with (ii) egg yolk powder derived from chickens challenged with Salmonella Typhimurium antigens, (iii) a commercial egg yolk powder control, (iv) apramycin for 14 days followed by carbadox, (v) oxytetracycline, or (vi) spray-dried plasma protein. Treatments were provided beginning on day 3 of the trial, and all pigs were challenged with 5 ml of 10(8) CFU/ml Salmonella Typhimurium on day 7. Fecal samples were collected on days 0, 7, 8, 12, 14, 21, 58, 88, and 118 for isolation of Salmonella and Escherichia coli to determine shedding and antibiotic resistance patterns. Body weights, white blood cell counts, and plasma concentrations of anti-Salmonella immunoglobulin G and porcine interleukin 1beta were analyzed as indicators of animal health. The percentage of pigs shedding Salmonella was lower for antibiotic treatment groups compared with other groups; however, resistance was greater in E. coli from pigs fed antibiotics than in pigs in other treatment groups. Health and performance indicators (pig weight gains, white blood cell counts, and plasma concentrations of anti-Salmonella antibodies) did not differ between treatment groups. These studies indicate that feeding egg yolk containing anti-Salmonella immunoglobulin Y may not be effective in controlling shedding of Salmonella in pigs.

EVOLUTION OF THE IMMUNE RESPONSE

PubMed Central

Papermaster, Ben W.; Condie, Richard M.; Finstad, Joanne; Good, Robert A.

1964-01-01

1. The California hagfish, Eptatretus stoutii, seems to be completely lacking in adaptive immunity: it forms no detectable circulating antibody despite intensive stimulation with a range of antigens; it does not show reactivity to old tuberculin following sensitization with BCG; and gives no evidence of homograft immunity. 2. Studies on the sea lamprey, Petromyzon marinus, have been limited to the response to bacteriophage T2 and hemocyanin in small groups of spawning animals. They suggest that the lamprey may have a low degree of immunologic reactivity. 3. One holostean, the bowfin (Amia calva) and the guitarfish (Rhinobatos productus), an elasmobranch, showed a low level of primary response to phage and hemocyanin. The response is slow and antibody levels low. Both the bowfin and the guitarfish showed a vigorous secondary response to phage, but neither showed much enhancement of reactivity to hemocyanin in the secondary response. The bowfin formed precipitating antibody to hemocyanin, but the guitarfish did not. Both hemagglutinating and precipitating antibody to hemocyanin were also observed in the primary response of the black bass. 4. The bowfin was successfully sensitized to Ascaris antigen, and lesions of the delayed type developed after challenge at varying intervals following sensitization. 5. The horned shark (Heterodontus franciscii) regularly cleared hemocyanin from the circulation after both primary and secondary antigenic stimulation, and regularly formed hemagglutinating antibody, but not precipitating antibody, after both primary and secondary stimulation with this antigen. These animals regularly cleared bacteriophage from the circulation after both the primary and secondary stimulation with bacteriophage T2. Significant but small amounts of antibody were produced in a few animals in the primary response, and larger amounts in the responding animals after secondary antigenic stimulation. 6. Studies by starch gel and immunoelectrophoresis show that the hagfish has no bands with mobilities of mammalian gamma globulins; that the lamprey has a single, relatively faint band of this type; and that multiple gamma bands are characteristic of the holostean, elasmobranchs, and teleosts studied. By this method of study, the bowfin appeared to have substantial amounts of gamma2 globulin. 7. We conclude that adaptive immunity and its cellular and humoral correlates developed in the lowest vertebrates, and that a rising level of immunologic reactivity and an increasingly differentiated and complex immunologic mechanism are observed going up the phylogenetic scale from the hagfish, to the lamprey, to the elasmobranchs, to the holosteans, and finally the teleosts. PMID:14113107

[Circulation of porcine enteroviruses and determination of their antigenic relations with human enteroviruses].

PubMed

Bozhok, L V; Derev'ianko, S V; Soroka, V I; Hrytsenko, L M; Zadorozhna, V I

2003-01-01

Strains of porcine enteroviruses (PEV) (n = 50), have been isolated from different animal species and environment objects: from pigs--19, mice--16, cats--3, rabbits--3, poultry--2, from objects of cattle-breeding premises--7. This testifies to PEV capacity to reproduction in the organism of hosts which are not characteristic of them. Some PEV strains cause cytopathogenic effect in human cell culture. No antigenic relations between 16 investigated strains of porcine enteroviruses and polimyelitis viruses of serotypes 1-3 and Coxsackie B5 were established.

Experimental autologous immune deposit nephritis in rats associated with mercuric chloride administration.

PubMed

Kelchner, J; McIntosh, J R; Boedecker, E; Guggenheim, S; McIntosh, R M

1976-09-15

Serial administration of mercuric chloride to rats was followed by development of antibodies to tubular basement membrane and renal tubular epithelial antigen (RTE) and glomerulonephritis characterized by granular deposits of hosts IgG, C3 and RTE along the glomerular capillary walls. The glomerular fixed antibody was directed against RTE. These studies suggest that tubular injury by mercury may lead to release of RTE and autosensitization and subsequent antibody production to this antigen result in formation of and glomerular deposition of circulating immunopathogenic complexes (RTE-anti-RTE) and glomerular morphologic alterations.

Soya protein antibodies in man: their occurrence and possible relevance in coeliac disease.

PubMed Central

Haeney, M R; Goodwin, B J; Barratt, M E; Mike, N; Asquith, P

1982-01-01

Circulating antibodies to soya-derived protein antigens have been measured in patients with duodenitis, Crohn's disease, ulcerative colitis and coeliac disease. Significantly raised antibody titres were found frequently in the coeliac group, particularly those patients showing a suboptimal response to a gluten-free diet, but rarely in subjects with other gastrointestinal diseases. Antisoya activity was not necessarily accompanied by antibodies to other common dietary antigens. We suggest that some coeliacs may have an associated dietary soya sensitivity which could adversely influence their response to gluten withdrawal. PMID:7040491

Immunological aspects of circulating DNA.

PubMed

Anker, Philippe; Stroun, Maurice

2006-09-01

Nude mice were injected with DNA released by T lymphocytes previously exposed to inactivated herpes symplex type 1 or polio viruses. The serum of these mice was tested for its neutralizing activity. Injected nude mice synthesized antiherpetic or antipolio antibodies, depending on the antigen used to sensitize the T lymphocytes. Mice injected with DNA released by human T cells produced antibodies carrying human allotypes as they could be neutralized by antiallotype sera. However, mice that were injected with DNA released by antigen-stimulated murine T lymphocytes produced antiviral antibodies, which were not neutralized by anti-human allotype sera.

DELAYED HYPERSENSITIVITY

PubMed Central

Uhr, Jonathan W.; Salvin, S. B.; Pappenheimer, A. M.

1957-01-01

A general method for induction of the delayed hypersensitive state directed against single protein antigens is described. The method consists of intradermal injection of minute amounts of washed immune precipitates containing the antigen in question. Provided the specific precipitates are formed in the region of antibody excess, maximal sensitivity develops at least 2 to 3 weeks before detectable circulating antibody is formed in guinea pigs against the sensitizing antigen. Neither adjuvant nor killed acid-fast bacteria are required for induction of the delayed hypersensitive state although the degree of sensitization is considerably increased when the sensitizing material is incorporated in Freund's complete adjuvant. Characteristics of the "delayed" as opposed to the "immediate" hypersensitive states in the guinea pig are described and implications of the findings are discussed. PMID:13385403

Anti-Vibriocholerae IgY Antibody Inhibits Mortality in Suckling Mice Model.

PubMed

Akbari, Mohammad Reza; Ahmadi, Ali; Mirkalantari, Shiva; Salimian, Jafar

2018-02-01

Regarding to the importance of cholera in Iran and the potential advantages of egg yolk antibody (IgY) for immunotherapy, the aim of this study was to produce IgY antibody against V. cholerae Lipopolysaccharide (LPS) and determine its potential for V. cholerae treatment. LPS was prepared, and the Anti-V. cholerae LPS IgY was purified from egg yolk and serially diluted in phosphate-buffered saline (PBS), mixed with V. cholerae and then gavaged into several groups of suckling mice. The yield of Anti-LPS IgY extraction was 40 mg/Egg yolk. The results demonstrated that up to approximately 75 ng of IgY can detect specifically V. cholerae. The lowest protective dose of anti-V. cholerae LPS IgY was 2.5 μg. The produced anti-Vibrio LPS specific IgY showed a good reactivity with its specific antigen and it may use as a complimentary oral immunotherapy for cholera disease. Copyright © 2018. Published by Elsevier Inc.

Egg yolks inhibit activation of NF-κB and expression of its target genes in adipocytes after partial delipidation

PubMed Central

Shen, Qiwen; Riedl, Ken M.; Cole, Rachel M.; Lehman, Christopher; Xu, Lu; Alder, Hansjuerg; Belury, Martha A.; Schwartz, Steven J.; Ziouzenkova, Ouliana

2015-01-01

How composition of egg yolk (EY) influences NF-κB, a key transcription pathway in inflammation, remains unclear. We performed partial delipidation of EY that removed 20–30% of cholesterol and triglycerides. The resulting polar and non-polar fractions were termed EY-P and EY-NP. NF-κB activation in response to EY from different suppliers and their fractions was examined in 3T3-L1 adipocytes using a NF-κB response element reporter assay and by analyzing expression of 248 inflammatory genes. Although EY-P and EY contained similar level of vitamins, carotenoids, and fatty acids, only delipidated EY-P fraction suppressed NF-κB via down-regulation of toll like receptor-2 and up-regulation of inhibitory toll interacting protein (Tollip) and lymphocyte antigen 96 (Ly96). Our data suggest that anti-inflammatory activity of lutein and retinol were blunted by non-polar lipids in EY likely via crosstalk between SREBP and NF-κB pathways in adipocytes. Thus, moderate delipidation may improve their beneficial properties of regular eggs. PMID:25620076

Effect of addition of a detoxifying agent to laying hen diets containing uncontaminated or Fusarium toxin-contaminated maize on performance of hens and on carryover of zearalenone.

PubMed

Dänicke, S; Ueberschär, K H; Halle, I; Matthes, S; Valenta, H; Flachowsky, G

2002-11-01

16-wk experiment with laying hens was carried out to examine the effects of feeding of mycotoxin-contaminated maize (CM) on performance, nutrient digestibility, weight of organs, serum chemical parameters, and antibody titers to Newcastle disease virus (NDV) in serum. Also tested were fimbrien antigen K88 in egg yolk and zearalenone (ZON) residues in eggs and tissues. The Fusarium-toxin-contaminated maize contained 17,630 microg deoxynivalenol and 1,580 microg ZON/kg. Moreover, Mycofix Plus (MP), a so-called detoxifying agent, was added to both the uncontaminated control (UCM) and to the CM diet (70% dietary maize inclusion). Each of the four resulting diets (UCM, UCM-MP, CM, CM-MP) was tested on 25 laying hybrids (Lohmann Brown). Feeding of the CM diets significantly depressed feed intake compared to the control groups by approximately 5%. This was mainly due to the effects observed at the beginning of the experiment. Daily egg mass production/hen was 56.6, 58.4, 53.9, and 55.2 g in groups UCM, UCM-MP, CM and CM-MP, respectively. Nutrient digestibility and metabolizability of gross energy were slightly depressed by feeding the CM diets and improved by MP addition. Feeding of the CM diets resulted in a significant decrease in serum titers to NDV and to an increase in yolk titers to antigen K88. No residues of ZON or of its metabolites were found in yolk, albumen, abdominal fat, breast meat, follicles greater than 1 cm in diameter, ovaries including follicles smaller than 1 cm in diameter, magnum, and serum. ZON and alpha-zearalenol (alpha-ZOL) were detected in livers of hens fed the CM diets at mean concentrations of 2.1 and 3.7 microg/kg, respectively. It was concluded that feeding maize which was highly contaminated with Fusarium mycotoxins adversely influenced performance of hens and modulated immune response. At the given level of zearalenone and at the indicated detection limits, no residues of ZON and its metabolites were found in eggs. The effects of the tested detoxifying agent were quite mycotoxin-independent.

Intercontinental circulation of human influenza A(H1N2) reassortant viruses during the 2001-2002 influenza season.

PubMed

Xu, Xiyan; Smith, Catherine B; Mungall, Bruce A; Lindstrom, Stephen E; Hall, Henrietta E; Subbarao, Kanta; Cox, Nancy J; Klimov, Alexander

2002-11-15

Reassortant influenza A viruses bearing the H1 subtype of hemagglutinin (HA) and the N2 subtype of neuraminidase (NA) were isolated from humans in the United States, Canada, Singapore, Malaysia, India, Oman, Egypt, and several countries in Europe during the 2001-2002 influenza season. The HAs of these H1N2 viruses were similar to that of the A/New Caledonia/20/99(H1N1) vaccine strain both antigenically and genetically, and the NAs were antigenically and genetically related to those of recent human H3N2 reference strains, such as A/Moscow/10/99(H3N2). All 6 internal genes of the H1N2 reassortants examined originated from an H3N2 virus. This article documents the first widespread circulation of H1N2 reassortants on 4 continents. The current influenza vaccine is expected to provide good protection against H1N2 viruses, because it contains the A/New Caledonia/20/99(H1N1) and A/Moscow/10/99(H3N2)-like viruses, which have H1 and N2 antigens that are similar to those of recent H1N2 viruses.

Non-covalent pomegranate (Punica granatum) hydrolyzable tannin-protein complexes modulate antigen uptake, processing and presentation by a T-cell hybridoma line co-cultured with murine peritoneal macrophages.

PubMed

Madrigal-Carballo, Sergio; Haas, Linda; Vestling, Martha; Krueger, Christian G; Reed, Jess D

2016-12-01

In this work we characterize the interaction of pomegranate hydrolyzable tannins (HT) with hen egg-white lysozyme (HEL) and determine the effects of non-covalent tannin-protein complexes on macrophage endocytosis, processing and presentation of antigen. We isolated HT from pomegranate and complex to HEL, the resulting non-covalent tannin-protein complex was characterized by gel electrophoresis and MALDI-TOF MS. Finally, cell culture studies and confocal microscopy imaging were conducted on the non-covalent pomegranate HT-HEL protein complexes to evaluate its effect on macrophage antigen uptake, processing and presentation to T-cell hybridomas. Our results indicate that non-covalent pomegranate HT-HEL protein complexes modulate uptake, processing and antigen presentation by mouse peritoneal macrophages. After 4 h of pre-incubation, only trace amounts of IL-2 were detected in the co-cultures treated with HEL alone, whereas a non-covalent pomegranate HT-HEL complex had already reached maximum IL-2 expression. Pomegranate HT may increase rate of endocytose of HEL and subsequent expression of IL-2 by the T-cell hybridomas.

Amino Acids in Hemagglutinin Antigenic Site B Determine Antigenic and Receptor Binding Differences between A(H3N2)v and Ancestral Seasonal H3N2 Influenza Viruses

PubMed Central

Wang, Xiaoquan; Ilyushina, Natalia A.; Lugovtsev, Vladimir Y.; Bovin, Nicolai V.; Couzens, Laura K.; Gao, Jin

2016-01-01

ABSTRACT Influenza A H3N2 variant [A(H3N2)v] viruses, which have caused human infections in the United States in recent years, originated from human seasonal H3N2 viruses that were introduced into North American swine in the mid-1990s, but they are antigenically distinct from both the ancestral and current circulating H3N2 strains. A reference A(H3N2)v virus, A/Minnesota/11/2010 (MN/10), and a seasonal H3N2 strain, A/Beijing/32/1992 (BJ/92), were chosen to determine the molecular basis for the antigenic difference between A(H3N2)v and the ancestral viruses. Viruses containing wild-type and mutant MN/10 or BJ/92 hemagglutinins (HAs) were constructed and probed for reactivity with ferret antisera against MN/10 and BJ/92 in hemagglutination inhibition assays. Among the amino acids that differ between the MN/10 and BJ/92 HAs, those in antigenic site A had little impact on the antigenic phenotype. Within antigenic site B, mutations at residues 156, 158, 189, and 193 of MN/10 HA to those in BJ/92 switched the MN/10 antigenic phenotype to that of BJ/92. Mutations at residues 156, 157, 158, 189, and 193 of BJ/92 HA to amino acids present in MN/10 were necessary for BJ/92 to become antigenically similar to MN/10. The HA amino acid substitutions responsible for switching the antigenic phenotype also impacted HA binding to sialyl receptors that are usually present in the human respiratory tract. Our study demonstrates that antigenic site B residues play a critical role in determining both the unique antigenic phenotype and receptor specificity of A(H3N2)v viruses, a finding that may facilitate future surveillance and risk assessment of novel influenza viruses. IMPORTANCE Influenza A H3N2 variant [A(H3N2)v] viruses have caused hundreds of human infections in multiple states in the United States since 2009. Most cases have been children who had contact with swine in agricultural fairs. These viruses originated from human seasonal H3N2 viruses that were introduced into the U.S. swine population in the mid-1990s, but they are different from both these ancestral viruses and current circulating human seasonal H3N2 strains in terms of their antigenic characteristics as measured by hemagglutination inhibition (HI) assay. In this study, we identified amino acids in antigenic site B of the surface glycoprotein hemagglutinin (HA) that explain the antigenic difference between A(H3N2)v and the ancestral H3N2 strains. These amino acid mutations also alter binding to minor human-type glycans, suggesting that host adaptation may contribute to the selection of antigenically distinct H3N2 variants which pose a threat to public health. PMID:27807224

Isolation of circulating immune complexes using Raji cells. Separation of antigens from immune complexes and production of antiserum.

PubMed Central

Theofilopoulos, A N; Eisenberg, R A; Dixon, F J

1978-01-01

Raji cells were used for the isolation of complement-fixing antigen-antibody complexes from serum. Immune complexes bound to these cells were radiolabeled at the cell surface with lactoperoxidase. The complexes were then eluted from the cells with isotonic citrate buffer pH 3.2 or recovered by immunoprecipitation of cell lysates. The antigen and antibody moieties of the complexes were isolated by dissociating sucrose density gradient centrifugation or by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A variety of preformed immune complexes were successfully isolated from serum with this approach. In addition, these techniques were used to isolate and identify the antigens in immune complexes in the serum of rabbits with chronic serum sickness and rats with Moloney virus-induced sarcomas. Methods were also developed for the production of antisera against the antigenic moiety of immune complexes isolated from serum. Repeated challenge of rabbits with whole Raji cells with bound complexes or eluates from such cells resulted in antibody production against the antigens of the immune complexes, although reactivity against cellular and serum components was also elicited. Monospecific antisera against the antigens in immune complexes were produced by immunizing rabbits with the alum-precipitated antigen isolated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These techniques may be useful in isolating antigens in immune complex-associated diseases of unknown etiology. Images PMID:659616

Adjuvants and alternative routes of administration towards the development of the ideal influenza vaccine.

PubMed

Durando, Paolo; Iudici, Rocco; Alicino, Cristiano; Alberti, Marisa; de Florentis, Daniela; Ansaldi, Filippo; Icardi, Giancarlo

2011-01-01

Vaccination is universally considered as the principal measure for the control of influenza, which represents a significant burden worldwide, both from a health-care and a socio-economic viewpoint. Conventional non-adjuvanted trivalent influenza vaccines (TIVs) have been recognized as having some deficiencies, such as suboptimal immunogenicity particularly in the elderly, in patients with severe chronic diseases and immunocompromized, indeed, those groups of the population at higher risk of developing severe complications following influenza infection, when compared to healthy adults. Moreover, the protection offered by conventional vaccines may be reduced by periodic antigenic drifts, resulting in a mismatch between the circulating and vaccinal viral strains. Another gap regarding currently available vaccines is related to the egg-based manufacturing system for their production: not only the length of time involved with the latter but also the limited capacity of this platform technology represent a major limitation for the active prevention of influenza, which is particularly important in the case of a new pandemic strain. New technologies used in vaccine composition, administration and manufacture have led to major advances during the last few years, and clinical researchers have continued to work hard, investigating several different strategies to improve the performance of influenza vaccines: namely, the addition of different adjuvants (i.e., MF59- and AS03-vaccines, virosomal formulations), the use of alternative routes of administration or manufacture (i.e., intradermal, nasal and oral vaccines and cell culture- and reverse genetic-based vaccines) or of high doses of antigen, and the development of DNA-vaccines, or the use of conserved viral epitopes (i.e., the extracellular portion of the M2 protein, the nucleoprotein and some domains of the hemagglutinin), in the attempt to produce a "universal target" antigen vaccine. The knowledge acquired represents a fundamental challenge for the control of influenza. An overview of the most recent and interesting results, some of which gained from our own research experience, particularly concerning two successful approaches, of those outlined above, namely the use of: (i) the oil-in-water MF59-adjuvant, and (ii) the intradermal (ID) route for vaccine administration, through a novel microinjection system, will be reported and discussed, together with the possible implications and perspectives to optimize immunization policies against influenza in the near future.

LBSapSal-vaccinated dogs exhibit increased circulating T-lymphocyte subsets (CD4+ and CD8+) as well as a reduction of parasitism after challenge with Leishmania infantum plus salivary gland of Lutzomyia longipalpis

PubMed Central

2014-01-01

Background The development of a protective vaccine against canine visceral leishmaniasis (CVL) is an alternative approach for interrupting the domestic cycle of Leishmania infantum. Given the importance of sand fly salivary proteins as potent immunogens obligatorily co-deposited during transmission of Leishmania parasites, their inclusion in an anti-Leishmania vaccine has been investigated in the last few decades. In this context, we previously immunized dogs with a vaccine composed of L. braziliensis antigens plus saponin as the adjuvant and sand fly salivary gland extract (LBSapSal vaccine). This vaccine elicited an increase in both anti-saliva and anti-Leishmania IgG isotypes, higher counts of specific circulating CD8+ T cells, and high NO production. Methods We investigated the immunogenicity and protective effect of LBSapSal vaccination after intradermal challenge with 1 × 107 late-log-phase L. infantum promastigotes in the presence of sand fly saliva of Lutzomyia longipalpis. The dogs were followed for up to 885 days after challenge. Results The LBSapSal vaccine presents extensive antigenic diversity with persistent humoral and cellular immune responses, indicating resistance against CVL is triggered by high levels of total IgG and its subtypes (IgG1 and IgG2); expansion of circulating CD5+, CD4+, and CD8+ T lymphocytes and is Leishmania-specific; and reduction of splenic parasite load. Conclusions These results encourage further study of vaccine strategies addressing Leishmania antigens in combination with proteins present in the saliva of the vector. PMID:24507702

Analysis of influenza A viruses of subtype H1 from wild birds, turkeys and pigs in Germany reveals interspecies transmission events.

PubMed

Starick, Elke; Fereidouni, Sasan R; Lange, Elke; Grund, Christian; Vahlenkamp, Thomas; Beer, Martin; Harder, Timm C

2011-07-01

Despite considerable host species barriers, interspecies transmissions of influenza A viruses between wild birds, poultry and pigs have been demonstrated repeatedly. In particular, viruses of the subtypes H1 and H3 were transmitted between pigs and poultry, predominantly turkeys, in regions with a high population density of both species. The recovery of a swine influenza H1N1 virus from a turkey flock in Germany in 2009 prompted us to investigate molecularly the subtype H1 viruses recently detected in wild birds, pigs and poultry. The goal of this study was to investigate the relationship between H1N1 viruses originating from wild and domestic animals of Germany and to identify potential trans-species transmission or reassortment events. Hemagglutinin and neuraminidase gene or full-length genome sequences were generated from selected, current H1N1 viruses from wild birds, pigs and turkeys. Phylogenetic analyses were combined with genotyping and analyses of the deduced amino acid sequences with respect to biologically active sites. Antigenic relationships were assessed by hemagglutination inhibition reactions. Phylogenetic analysis of the hemagglutinin sequences showed that viruses from distinct H1 subgroups co-circulate among domestic animals and wild birds. In addition, these viruses comprised different genotypes and were distinguishable antigenically. An H1N1 virus isolated from a turkey farm in northern Germany in 2009 showed the highest similarity with the avian-like porcine H1N1 influenza viruses circulating in Europe since the late 1970s. The data demonstrate the genetic and antigenic heterogeneity of H1 viruses currently circulating in domestic and wild animals in Germany and points to turkeys as a possible bridge between avian and mammalian hosts. © 2011 Blackwell Publishing Ltd.

Loss of sensitivity of immunochromatographic test (ICT) for lymphatic filariasis diagnosis in low prevalence settings: consequence in the monitoring and evaluation procedures.

PubMed

Gounoue-Kamkumo, Raceline; Nana-Djeunga, Hugues C; Bopda, Jean; Akame, Julie; Tarini, Ann; Kamgno, Joseph

2015-12-23

Diagnostic tools for lymphatic filariasis (LF) elimination programs are useful in mapping the distribution of the disease, delineating areas where mass drug administrations (MDA) are required, and determining when to stop MDA. The prevalence and burden of LF have been drastically reduced following mass treatments, and the evaluation of the performance of circulating filarial antigen (CFA)-based assays was acknowledged to be of high interest in areas with low residual LF endemicity rates after multiple rounds of MDA. The objective of this study was therefore to evaluate the immunochromatographic test (ICT) sensitivity in low endemicity settings and, specifically, in individuals with low intensity of lymphatic filariasis infection. To perform this study, calibrated thick blood smears, ICT and Og4C3 enzyme-linked immunosorbent assay (ELISA) were carried out by night to identify Wuchereria bancrofti microfilarial and circulating filarial antigen carriers. A threshold determination assay regarding ICT and ELISA was performed using serial plasma dilutions from individuals with positive microfilarial counts. All individuals harbouring microfilariae (positive blood films) were detected by ICT and ELISA, but among individuals positive for ELISA, only 35.7 % of them were detected using ICT (Chi square: 4.57; p-value = 0.03), indicating a moderate agreement between both tests (kappa statistics = 0.49). Threshold determination analyses showed that ELISA was still positive at the last plasma dilution with negative ICT result. These findings suggest a loss of sensitivity for ICT in low endemicity settings, especially in people exhibiting low levels of circulating filarial antigen, raising serious concern regarding the monitoring and evaluation procedures in the framework of LF elimination program.

Comparative efficacy of storage bags, storability and damage potential of bruchid beetle.

PubMed

Harish, G; Nataraja, M V; Ajay, B C; Holajjer, Prasanna; Savaliya, S D; Gedia, M V

2014-12-01

Groundnut during storage is attacked by number of stored grain pests and management of these insect pests particularly bruchid beetle, Caryedon serratus (Oliver) is of prime importance as they directly damage the pod and kernels. In this regard different storage bags that could be used and duration up to which we can store groundnut has been studied. Super grain bag recorded minimum number of eggs laid and less damage and minimum weight loss in pods and kernels in comparison to other storage bags. Analysis of variance for multiple regression models were found to be significant in all bags for variables viz, number of eggs laid, damage in pods and kernels, weight loss in pods and kernels throughout the season. Multiple comparison results showed that there was a high probability of eggs laid and pod damage in lino bag, fertilizer bag and gunny bag, whereas super grain bag was found to be more effective in managing the C. serratus owing to very low air circulation.

Ambiguities in the relationship between gonadal steroids and reproduction in axolotls (Ambystoma mexicanum).

PubMed

Eisthen, Heather L; Krause, Brianne Chung

2012-05-01

Axolotls (Ambystoma mexicanum) are aquatic salamanders that are widely used in research. Axolotls have been bred in laboratories for nearly 150 years, yet little is known about the basic biology of reproduction in these animals. We investigated the effects of changing day length, time of year, and food availability on levels of circulating estradiol and androgens in adult female and male axolotls, respectively. In addition, we examined the effects of these variables on the mass of ovaries, oviducts, and eggs in females and on mass of testes in males relative to each individual's body weight, to calculate a form of gonadosomatic index (GSI). In both sexes, GSI was not correlated with levels of circulating steroids. In female axolotls, estradiol levels were influenced by food availability, changes in day length, and season, even when animals were held at a constant temperature and day length was decorrelated with calendar date. In addition, the mass of ovaries, oviducts, and eggs varied seasonally, peaking in the winter months and declining during the summer months, even though our animals were not breeding and shedding eggs. In males, levels of androgens appeared to vary independently of external conditions, but GSI varied dramatically with changes in day length. These results suggest that reproduction in axolotls may vary seasonally, as it does in many other ambystomid species, although both male and female axolotls are capable of reproducing several times each year. The physiological basis of this ability remains enigmatic, given the indications of seasonality contained in our data. Copyright © 2012 Elsevier Inc. All rights reserved.

Potentiation of pH-sensitive polymer-modified liposomes with cationic lipid inclusion as antigen delivery carriers for cancer immunotherapy.

PubMed

Yoshizaki, Yuta; Yuba, Eiji; Sakaguchi, Naoki; Koiwai, Kazunori; Harada, Atsushi; Kono, Kenji

2014-09-01

Cationic lipid-incorporated liposomes modified with pH-sensitive polymers were prepared by introducing 3, 5-didodecyloxybenzamidine as a cationic lipid to egg yolk phosphatidylcholine liposomes modified with 3-methylglutarylated hyperbranched poly(glycidol) (MGlu-HPG) as a pH-sensitive polymer. These liposomes were stable at neutral pH, but were destabilized below pH 6.0 because MGlu-HPG changed its characteristics from hydrophilic to hydrophobic in response to the pH decrease. Cationic lipid inclusion improved their pH sensitivity at weakly acidic pH and association of liposomes with murine dendritic cell (DC) lines. Cationic lipid-incorporated liposomes delivered entrapped ovalbumin (OVA) molecules not only to cytosol but also to endosome/lysosome. Treatment with cationic lipid-incorporated liposomes induced up-regulation of antigen presentation-involved molecules on DCs, the promotion of cytokine production, and antigen presentation via both major histocompatibility complex (MHC) class I and II molecules. Especially, antigen presentation via MHC class II was promoted by cationic lipid inclusion, which might correspond to efficient endosome/lysosome delivery of OVA. Subcutaneous administration of OVA-loaded cationic lipid-incorporated liposomes induced antigen-specific antibody production in serum and Th1-dominant immune responses in the spleen. Furthermore, administration of the cationic lipid-incorporated liposomes to mice bearing E.G7-OVA tumor more significantly reduced the tumor volume than liposomes without cationic lipids. Therefore, cationic lipid inclusion into pH-sensitive polymer-modified liposomes, which can achieve both efficient antigen intracellular delivery and activation of antigen presenting cell, is an effective approach to develop antigen carriers for efficient cancer immunotherapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

Specific Fluorine Labeling of the HyHEL10 Antibody Affects Antigen Binding and Dynamics

PubMed Central

Acchione, Mauro; Lee, Yi-Chien; DeSantis, Morgan E.; Lipschultz, Claudia A.; Wlodawer, Alexander; Li, Mi; Shanmuganathan, Aranganathan; Walter, Richard L.; Smith-Gill, Sandra; Barchi, Joseph J.

2012-01-01

To more fully understand the molecular mechanisms responsible for variations in binding affinity with antibody maturation, we explored the use of site specific fluorine labeling and 19F nuclear magnetic resonance (NMR). Several single-chain (scFv) antibodies, derived from an affinity-matured series of anti-hen egg white lysozyme (HEL) mouse IgG1, were constructed with either complete or individual replacement of tryptophan residues with 5-fluorotryptophan (5FW). An array of biophysical techniques was used to gain insight into the impact of fluorine substitution on the overall protein structure and antigen binding. SPR measurements indicated that 5FW incorporation lowered binding affinity for the HEL antigen. The degree of analogue impact was residue-dependent, and the greatest decrease in affinity was observed when 5FW was substituted for residues near the binding interface. In contrast, corresponding crystal structures in complex with HEL were essentially indistinguishable from the unsubstituted antibody. 19F NMR analysis showed severe overlap of signals in the free fluorinated protein that was resolved upon binding to antigen, suggesting very distinct chemical environments for each 5FW in the complex. Preliminary relaxation analysis suggested the presence of chemical exchange in the antibody–antigen complex that could not be observed by X-ray crystallography. These data demonstrate that fluorine NMR can be an extremely useful tool for discerning structural changes in scFv antibody–antigen complexes with altered function that may not be discernible by other biophysical techniques. PMID:22769726

Epidemiological evolution of canine parvovirus in the Portuguese domestic dog population.

PubMed

Miranda, Carla; Parrish, Colin R; Thompson, Gertrude

2016-02-01

Since its emergence, canine parvovirus type 2 (CPV-2) has caused disease pandemics with severe gastroenteritis signs, infecting especially puppies. As a consequence of CPV rapid evolution a variety of genetic and antigenic variants have been reported circulating worldwide. The detection of additional variants of CPV circulating in the dog population in Portugal suggests monitoring of the disease is useful. The objectives of this study were to further detect and characterize circulating field variants from suspected CPV diseased dogs that were admitted to veterinary clinics distributed throughout the country, during 2012-2014. Of the 260 fecal samples collected, 198 were CPV positive by PCR, and CPV antigen was detected in 61/109 samples by Immunochromatographic (IC) test. The restriction fragment length polymorphism (RFLP) analysis of 167 samples revealed that 86 were the CPV-2c. Sequence analysis of the 198 strains confirmed that CPV-2c were the dominant variant (51.5%), followed by CPV-2b (47.5%) and CPV-2a (1%). The variants were irregularly distributed throughout the country and some were detected with additional non-synonymous mutations in the VP2 gene. Phylogenetic analysis demonstrated that the isolates were similar to other European strains, and that this virus continues to evolve. Copyright © 2015 Elsevier B.V. All rights reserved.

Immunodiagnostic monoclonal antibody-based sandwich ELISA of fasciolosis by detection of Fasciola gigantica circulating fatty acid binding protein.

PubMed

Anuracpreeda, Panat; Chawengkirttikul, Runglawan; Sobhon, Prasert

2016-09-01

Up to now, parasitological diagnosis of fasciolosis is often unreliable and possesses low sensitivity. Hence, the detection of circulating parasite antigens is thought to be a better alternative for diagnosis of fasciolosis, as it reflects the real parasite burden. In the present study, a monoclonal antibody (MoAb) against recombinant Fasciola gigantica fatty acid binding protein (rFgFABP) has been produced. As well, a reliable sandwich enzyme-linked immunosorbent assay (sandwich ELISA) has been developed for the detection of circulating FABP in the sera of mice experimentally and cattle naturally infected with F. gigantica. MoAb 3A3 and biotinylated rabbit anti-recombinant FABP antibody were selected due to their high reactivities and specificities. The lower detection limit of sandwich ELISA was 5 pg mL-1, and no cross-reaction with other parasite antigens was observed. This assay could detect F. gigantica infection from day 1 post infection. In experimental mice, the sensitivity, specificity and accuracy of this assay were 93·3, 100 and 98·2%, while in natural cattle they were 96·7, 100 and 99·1%. Hence, this sandwich ELISA method showed high efficiencies and precisions for diagnosis of fasciolosis by F. gigantica.

[Genetic variants of the Crimean-Congo hemorrhagic fever virus circulating in endemic areas of the southern Tajikistan in 2009].

PubMed

Petrova, I D; Kononova, Iu V; Chausov, E V; Shestopalov, A M; Tishkova, F Kh

2013-01-01

506 Hyalomma anatolicum ticks were collected and assayed in two Crimean-Congo hemorrhagic fever (CCHF) endemic regions of Tajikistan. Antigen and RNA of CCHF virus were detected in 3.4% of tick pools from Rudaki district using ELISA and RT-PCR tests. As of Tursunzade district, viral antigen was identified in 9.0% of samples and viral RNA was identified in 8.1% of samples. The multiple alignment of the obtained nucleotide sequences of CCHF virus genome S-segment 287-nt region (996-1282) and multiple alignment of deduced amino acid sequences of the samples, carried out to compare with CCHF virus strains from the GenBank database, as well as phylogenetic analysis, enabled us to conclude that Asia 1 and Asia 2 genotypes of CCHF virus are circulating in Tajikistan. It is important to note that the genotype Asia 1 virus was detected for the first time in Tajikistan.

Concurrent detection of secreted products from human lymphocytes by microengraving: cytokines and antigen-reactive antibodies

PubMed Central

Bradshaw, Elizabeth M.; Kent, Sally C.; Tripuraneni, Vinay; Orban, Tihamer; Ploegh, Hidde L.; Hafler, David A.; Love, J. Christopher

2008-01-01

Cell surface determinants, cytokines and antibodies secreted by hematopoietic cells are used to classify their lineage and function. Currently available techniques are unable to elucidate multiple secreted proteins while also assigning phenotypic surface-displayed markers to the individual living cells. Here, a soft lithographic method, microengraving, was adapted for the multiplexed interrogation of populations of individual human peripheral blood mononuclear cells for secreted cytokines (IFN-γ and IL-6), antigen-specific antibodies, and lineage-specific surface-expressed markers. Application of the method to a clinical sample from a recent onset Type 1 diabetic subject with a positive titer of anti-insulin antibodies showed that ~0.58% of circulating CD19+ B cells secreted proinsulin-reactive antibodies of the IgG isotype and 2–3% of circulating cells secreted IL-6. These data demonstrate the utility of microengraving for interrogating multiple phenotypes of single human cells concurrently and for detecting rare populations of cells by their secreted products. PMID:18675591

A review of the value of quadrivalent influenza vaccines and their potential contribution to influenza control

PubMed Central

Ray, Riju; Dos Santos, Gaël; Buck, Philip O.; Claeys, Carine; Matias, Gonçalo; Innis, Bruce L.; Bekkat-Berkani, Rafik

2017-01-01

ABSTRACT The contribution of influenza B to the seasonal influenza burden varies from year-to-year. Although 2 antigenically distinct influenza B virus lineages have co-circulated since 2001, trivalent influenza vaccines (TIVs) contain antigens from only one influenza B virus. B-mismatch or co-circulation of both B lineages results in increased morbidity and mortality attributable to the B lineage absent from the vaccine. Quadrivalent vaccines (QIVs) contain both influenza B lineages. We reviewed currently licensed QIVs and their value by focusing on the preventable disease burden. Modeling studies support that QIVs are expected to prevent more influenza cases, hospitalisations and deaths than TIVs, although estimates of the case numbers prevented vary according to local specificities. The value of QIVs is demonstrated by their capacity to broaden the immune response and reduce the likelihood of a B-mismatched season. Some health authorities have preferentially recommended QIVs over TIVs in their influenza prevention programmes. PMID:28532276

A survey of helminthic infections in the residents of rural areas near Ulaanbaatar, Mongolia

PubMed Central

Lee, Do-Sung; Chung, Byung-Ha; Lee, Nam-Seok; Kim, Joong-Ho

1999-01-01

A total of 738 samples was collected to survey the helminthic infections of residents in two rural areas near Ulaanbaatar, Mongolia for 2 weeks from July 23 to August 2, 1998. Among 391 scotch-taped slides of anal swabs of children and of young teenagers, Enterobius vermicularis eggs were detected in 138 cases (35.3%). With the fecal samples of 206 Kato-Katz thick smear slides from adults, the eggs of E. vermicularis were observed in 9 cases and Taenia sp. in one case, respectively. And by ELISA on 141 blood samples absorbed to blood sampling paper, 12 cases (8.5%) were found to be positive against the hydatid cyst antigen. Enterobiasis and hydatidosis are two major endemic diseases which are related closely to the life style of Mongolian. PMID:10507221

The Third International Reference Preparation of Egg Lecithin

PubMed Central

Krag, P.; Bentzon, M. Weis

1961-01-01

The Third International Reference Preparation of Egg Lecithin was produced (in a quantity of 5000 ml) at the WHO Serological Reference Centre, Copenhagen, and assayed in 1958 against the Second International Reference Preparation by four laboratories in three countries. Complement-fixation and slide-flocculation tests were used. The new preparation was found acceptable, and its establishment was authorized by the WHO Expert Committee on Biological Standardization. The average log10 titres and results of analyses of variances are shown. The variances were of the usual order of magnitude, and the differences in titre between antigens containing the Second and the Third International Reference Preparations varied from -0.011 to 0.116; only one of the differences exceeded the 5% limit of significance. The use of the Third International Reference Preparation in tests for the acceptability of lecithin preparations is described. PMID:13753864

Aflatoxin Contamination in Food and Body Fluids in Relation to Malnutrition and Cancer Status in Cameroon

PubMed Central

Tchana, Angele N.; Moundipa, Paul F.; Tchouanguep, Félicité M.

2010-01-01

Aflatoxins are food contaminants usually associated with hepatitis, immunodepression, impairment of fertility and cancer. The present work was to determine the presence of aflatoxins in eggs, milk, urine, and blood samples that were collected from various sources and periods; and hepatitis B virus antigen in blood samples. Aflatoxin was found in eggs (45.2%), cow raw milk (15.9%), breast milk (4.8%), urine from kwashiorkor and marasmic kwashiorkor children (45.5%), and sera from primary liver cancer patients (63.9%); HbsAg was also detected in 69.4% of the serum samples, but there was no association between both factors. Both AF and hepatitis B virus seem to be risk factors that could increase the incidence and prevalence rates of malnutrition and cancer in Cameroon. PMID:20195440

Automated Microfluidic Filtration and Immunocytochemistry Detection System for Capture and Enumeration of Circulating Tumor Cells and Other Rare Cell Populations in Blood.

PubMed

Pugia, Michael; Magbanua, Mark Jesus M; Park, John W

2017-01-01

Isolation by size using a filter membrane offers an antigen-independent method for capturing rare cells present in blood of cancer patients. Multiple cell types, including circulating tumor cells (CTCs), captured on the filter membrane can be simultaneously identified via immunocytochemistry (ICC) analysis of specific cellular biomarkers. Here, we describe an automated microfluidic filtration method combined with a liquid handling system for sequential ICC assays to detect and enumerate non-hematologic rare cells in blood.

The Influence of Socio-economic, Behavioural and Environmental Factors on Taenia spp. Transmission in Western Kenya: Evidence from a Cross-Sectional Survey in Humans and Pigs.

PubMed

Wardrop, Nicola A; Thomas, Lian F; Atkinson, Peter M; de Glanville, William A; Cook, Elizabeth A J; Wamae, C Njeri; Gabriël, Sarah; Dorny, Pierre; Harrison, Leslie J S; Fèvre, Eric M

2015-12-01

Taenia spp. infections, particularly cysticercosis, cause considerable health impacts in endemic countries. Despite previous evidence of spatial clustering in cysticercosis and the role of environmental factors (e.g. temperature and humidity) in the survival of eggs, little research has explored these aspects of Taenia spp. In addition, there are significant gaps in our understanding of risk factors for infection in humans and pigs. This study aimed to assess the influence of socio-economic, behavioural and environmental variables on human and porcine cysticercosis. A cross-sectional survey for human taeniasis (T. solium and T. saginata), human cysticercosis (T. solium) and pig cysticercosis (T. solium) in 416 households in western Kenya was carried out. These data were linked to questionnaire responses and environmental datasets. Multi-level regression was used to examine the relationships between covariates and human and porcine cysticercosis. The HP10 Ag-ELISA sero-prevalence (suggestive of cysticercosis) was 6.6% for humans (95% CI 5.6%-7.7%), and 17.2% for pigs (95% CI 10.2%-26.4%). Human taeniasis prevalence, based on direct microscopic observation of Taenia spp. eggs (i.e. via microscopy results only) was 0.2% (95% CI 0.05%-0.5%). Presence of Taenia spp. antigen in both humans and pigs was significantly associated with a range of factors, including positive correlations with land cover. The presence of HP10 antigen in humans was correlated (non-linearly) with the proportion of land within a 1 km buffer that was flooding agricultural land and grassland (odds ratio [OR] = 1.09 and 0.998; p = 0.03 and 0.03 for the linear and quadratic terms respectively), gender (OR = 0.58 for males compared to females, p = 0.02), level of education (OR = 0.62 for primary level education versus no formal education, p = 0.09), use of well water for drinking (OR = 2.76 for those who use well water versus those who do not, p = 0.02) and precipitation (OR = 0.998, p = 0.02). Presence of Taenia spp. antigen in pigs was significantly correlated with gender and breeding status of the pig (OR = 10.35 for breeding sows compared to boars, p = 0.01), and the proportion of land within a 1 km buffer that was flooding agricultural land and grassland (OR = 1.04, p = 0.004). These results highlight the role of multiple socio-economic, behavioural and environmental factors in Taenia spp. transmission patterns. Environmental contamination with Taenia spp. eggs is a key issue, with landscape factors influencing presence of Taenia spp. antigens in both pigs and humans.

The Influence of Socio-economic, Behavioural and Environmental Factors on Taenia spp. Transmission in Western Kenya: Evidence from a Cross-Sectional Survey in Humans and Pigs

PubMed Central

Wardrop, Nicola A.; Thomas, Lian F.; Atkinson, Peter M.; de Glanville, William A.; Cook, Elizabeth A. J.; Wamae, C. Njeri; Gabriël, Sarah; Dorny, Pierre; Harrison, Leslie J. S.; Fèvre, Eric M.

2015-01-01

Taenia spp. infections, particularly cysticercosis, cause considerable health impacts in endemic countries. Despite previous evidence of spatial clustering in cysticercosis and the role of environmental factors (e.g. temperature and humidity) in the survival of eggs, little research has explored these aspects of Taenia spp. epidemiology. In addition, there are significant gaps in our understanding of risk factors for infection in humans and pigs. This study aimed to assess the influence of socio-economic, behavioural and environmental variables on human and porcine cysticercosis. A cross-sectional survey for human taeniasis (T. solium and T. saginata), human cysticercosis (T. solium) and pig cysticercosis (T. solium) in 416 households in western Kenya was carried out. These data were linked to questionnaire responses and environmental datasets. Multi-level regression was used to examine the relationships between covariates and human and porcine cysticercosis. The HP10 Ag-ELISA sero-prevalence (suggestive of cysticercosis) was 6.6% for humans (95% CI 5.6%–7.7%), and 17.2% for pigs (95% CI 10.2%–26.4%). Human taeniasis prevalence, based on direct microscopic observation of Taenia spp. eggs (i.e. via microscopy results only) was 0.2% (95% CI 0.05%–0.5%). Presence of Taenia spp. antigen in both humans and pigs was significantly associated with a range of factors, including positive correlations with land cover. The presence of HP10 antigen in humans was correlated (non-linearly) with the proportion of land within a 1 km buffer that was flooding agricultural land and grassland (odds ratio [OR] = 1.09 and 0.998; p = 0.03 and 0.03 for the linear and quadratic terms respectively), gender (OR = 0.58 for males compared to females, p = 0.02), level of education (OR = 0.62 for primary level education versus no formal education, p = 0.09), use of well water for drinking (OR = 2.76 for those who use well water versus those who do not, p = 0.02) and precipitation (OR = 0.998, p = 0.02). Presence of Taenia spp. antigen in pigs was significantly correlated with gender and breeding status of the pig (OR = 10.35 for breeding sows compared to boars, p = 0.01), and the proportion of land within a 1 km buffer that was flooding agricultural land and grassland (OR = 1.04, p = 0.004). These results highlight the role of multiple socio-economic, behavioural and environmental factors in Taenia spp. transmission patterns. Environmental contamination with Taenia spp. eggs is a key issue, with landscape factors influencing presence of Taenia spp. antigens in both pigs and humans. PMID:26641459

Anergic self-reactive B cells present self antigen and respond normally to CD40-dependent T-cell signals but are defective in antigen-receptor-mediated functions.

PubMed Central

Eris, J M; Basten, A; Brink, R; Doherty, K; Kehry, M R; Hodgkin, P D

1994-01-01

B-cell tolerance to soluble protein self antigens such as hen egg lysozyme (HEL) is mediated by clonal anergy. Anergic B cells fail to mount antibody responses even in the presence of carrier-primed T cells, suggesting an inability to activate or respond to T helper cells. To investigate the nature of this defect, B cells from tolerant HEL/anti-HEL double-transgenic mice were incubated with a membrane preparation from activated T-cell clones expressing the CD40 ligand. These membranes, together with interleukin 4 and 5 deliver the downstream antigen-independent CD40-dependent B-cell-activating signals required for productive T-B collaboration. Anergic B cells responded to this stimulus by proliferating and secreting antibody at levels comparable to or better than control B cells. Furthermore, anergic B cells presented HEL acquired in vivo and could present the unrelated antigen, conalbumin, targeted for processing via surface IgD. In contrast, the low immunoglobulin receptor levels on anergic B cells were associated with reduced de novo presentation of HEL and a failure to upregulate costimulatory ligands for CD28. These defects in immunoglobulin-receptor-mediated functions could be overcome in vivo, suggesting a number of mechanisms for induction of autoantibody responses. Images PMID:7514304

Antigenic variation of H1N1, H1N2 and H3N2 swine influenza viruses in Japan and Vietnam.

PubMed

Takemae, Nobuhiro; Nguyen, Tung; Ngo, Long Thanh; Hiromoto, Yasuaki; Uchida, Yuko; Pham, Vu Phong; Kageyama, Tsutomu; Kasuo, Shizuko; Shimada, Shinichi; Yamashita, Yasutaka; Goto, Kaoru; Kubo, Hideyuki; Le, Vu Tri; Van Vo, Hung; Do, Hoa Thi; Nguyen, Dang Hoang; Hayashi, Tsuyoshi; Matsuu, Aya; Saito, Takehiko

2013-04-01

The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production.

Transformation of lymphocytes by Herpesvirus papio.

PubMed

Falk, L A; Henle, G; Henle, W; Deinhardt, F; Schudel, A

1977-08-15

Cotton-topped (CT) or white-lipped (WL) marmoset lymphocytes were transformed in vitro with herpesvirus papio (HVP) into permanently growing lymphoblastoid cell lines (LCL). Five of 9 HVP-transformed CT cell lines contained cells with antigens reacting with antibodies to Epstein-Barr virus (EBV) capsid antigen (VCA) and/or to EBV-induced early antigens (EA). None of 12 WL LCL revealed such antigen-producing cells. Cells from both groups of cultures failed to react with antibodies to the EBV-specified nuclear antigen (EBNA). Exposure of baboon circulating lymphocytes to X-irradiated HVP or EBV-carring cells, or to suspensions of EBV resulted in establishment of LCL which all contained VCA and/or EA-positive, but no EBNA-positive cells. Nuclear antigens were undetectable also with anti-VCA-positive sera from baboons, chimpanzees, or other non-human primates. DNA-complementary RNA (cRNA) filter hybridization with EBV cRNA showed that with one exception transformed CT or WL marmoset cells contained at least 1-2 virus genome equivalents per cell, while at least 12-25 virus genome equivalents per cell were detected in transformed baboon cells. These data need confirmation by DNA-DNA reassociation kinetics.

Broad blockade antibody responses in human volunteers after immunization with a multivalent norovirus VLP candidate vaccine: immunological analyses from a phase I clinical trial.

PubMed

Lindesmith, Lisa C; Ferris, Martin T; Mullan, Clancy W; Ferreira, Jennifer; Debbink, Kari; Swanstrom, Jesica; Richardson, Charles; Goodwin, Robert R; Baehner, Frank; Mendelman, Paul M; Bargatze, Robert F; Baric, Ralph S

2015-03-01

Human noroviruses (NoVs) are the primary cause of acute gastroenteritis and are characterized by antigenic variation between genogroups and genotypes and antigenic drift of strains within the predominant GII.4 genotype. In the context of this diversity, an effective NoV vaccine must elicit broadly protective immunity. We used an antibody (Ab) binding blockade assay to measure the potential cross-strain protection provided by a multivalent NoV virus-like particle (VLP) candidate vaccine in human volunteers. Sera from ten human volunteers immunized with a multivalent NoV VLP vaccine (genotypes GI.1/GII.4) were analyzed for IgG and Ab blockade of VLP interaction with carbohydrate ligand, a potential correlate of protective immunity to NoV infection and illness. Immunization resulted in rapid rises in IgG and blockade Ab titers against both vaccine components and additional VLPs representing diverse strains and genotypes not represented in the vaccine. Importantly, vaccination induced blockade Ab to two novel GII.4 strains not in circulation at the time of vaccination or sample collection. GII.4 cross-reactive blockade Ab titers were more potent than responses against non-GII.4 VLPs, suggesting that previous exposure history to this dominant circulating genotype may impact the vaccine Ab response. Further, antigenic cartography indicated that vaccination preferentially activated preexisting Ab responses to epitopes associated with GII.4.1997. Study interpretations may be limited by the relevance of the surrogate neutralization assay and the number of immunized participants evaluated. Vaccination with a multivalent NoV VLP vaccine induces a broadly blocking Ab response to multiple epitopes within vaccine and non-vaccine NoV strains and to novel antigenic variants not yet circulating at the time of vaccination. These data reveal new information about complex NoV immune responses to both natural exposure and to vaccination, and support the potential feasibility of an efficacious multivalent NoV VLP vaccine for future use in human populations. ClinicalTrials.gov NCT01168401.

Broad Blockade Antibody Responses in Human Volunteers after Immunization with a Multivalent Norovirus VLP Candidate Vaccine: Immunological Analyses from a Phase I Clinical Trial

PubMed Central

Lindesmith, Lisa C.; Ferris, Martin T.; Mullan, Clancy W.; Ferreira, Jennifer; Debbink, Kari; Swanstrom, Jesica; Richardson, Charles; Goodwin, Robert R.; Baehner, Frank; Mendelman, Paul M.; Bargatze, Robert F.; Baric, Ralph S.

2015-01-01

Background Human noroviruses (NoVs) are the primary cause of acute gastroenteritis and are characterized by antigenic variation between genogroups and genotypes and antigenic drift of strains within the predominant GII.4 genotype. In the context of this diversity, an effective NoV vaccine must elicit broadly protective immunity. We used an antibody (Ab) binding blockade assay to measure the potential cross-strain protection provided by a multivalent NoV virus-like particle (VLP) candidate vaccine in human volunteers. Methods and Findings Sera from ten human volunteers immunized with a multivalent NoV VLP vaccine (genotypes GI.1/GII.4) were analyzed for IgG and Ab blockade of VLP interaction with carbohydrate ligand, a potential correlate of protective immunity to NoV infection and illness. Immunization resulted in rapid rises in IgG and blockade Ab titers against both vaccine components and additional VLPs representing diverse strains and genotypes not represented in the vaccine. Importantly, vaccination induced blockade Ab to two novel GII.4 strains not in circulation at the time of vaccination or sample collection. GII.4 cross-reactive blockade Ab titers were more potent than responses against non-GII.4 VLPs, suggesting that previous exposure history to this dominant circulating genotype may impact the vaccine Ab response. Further, antigenic cartography indicated that vaccination preferentially activated preexisting Ab responses to epitopes associated with GII.4.1997. Study interpretations may be limited by the relevance of the surrogate neutralization assay and the number of immunized participants evaluated. Conclusions Vaccination with a multivalent NoV VLP vaccine induces a broadly blocking Ab response to multiple epitopes within vaccine and non-vaccine NoV strains and to novel antigenic variants not yet circulating at the time of vaccination. These data reveal new information about complex NoV immune responses to both natural exposure and to vaccination, and support the potential feasibility of an efficacious multivalent NoV VLP vaccine for future use in human populations. Trial Registration ClinicalTrials.gov NCT01168401 PMID:25803642

Using the AD12-ICT rapid-format test to detect Wuchereria bancrofti circulating antigens in comparison to Og4C3-ELISA and nucleopore membrane filtration and microscopy techniques.

PubMed

El-Moamly, Amal Abdul-Rasheed; El-Sweify, Mohamed Aly; Hafez, Mohamad Abdul

2012-09-01

Lymphatic filariasis (LF) continues to be a major source of permanent disability and an impediment to socio-economic development in 73 countries where more than 1 billion people are at risk and over 120 millions are infected. The global drive to eliminate LF necessitates an increasing demand for valid, reliable and rapid diagnostic tests. This study aimed to assess the performance of the AD12 rapid format immunochromatographic test (ICT) to detect Wuchereria bancrofti circulating antigens, against the combined gold standard: TropBio Og4C3-ELISA (enzyme-linked immunosorbent assay) which detects circulating filarial antigen (CFA) and the nucleopore membrane filtration and microscopic examination. This prospective case-control study involved 647 asymptomatic migrant workers from filariasis-endemic countries. Of these specimens, 32 were positive for microfilaremia using the membrane filtration and microscopy, 142 positive by ELISA (of which 32 had microfilaremia), and 128 positive by the ICT (of which 31 had microfilaremia). The performance of the ICT was calculated against 32 true-positive and 90 true-negative cases. For the detection of CFA, the ICT had a sensitivity of 97% (95% confidence interval [CI] 91-103), specificity 100% (95% CI 100-100), Positive Predictive Value (PPV) 100% (95% CI 100-100), Negative Predictive Value (NPV) 99% (95% CI 97-101); and the total accuracy of the test was 99% (95% CI 98-101). The agreement between ICT and ELISA in detecting W. bancrofti antigens was excellent (kappa = 0.934; p = 0.000). In conclusion, the AD12-ICT test for the detection of W. bancrofti-CFA was sensitive and specific and comparable to the performance of ELISA. The ICT would be a useful additional test to facilitate the proposed strategies for control and elimination of LF. Because it is rapid, simple to perform, and does not require the use of special equipment, the ICT may be most appropriate in screening programs and in monitoring the possible risk of introducing the disease to the non-endemic countries.

Antigenically Diverse Swine Origin H1N1 Variant Influenza Viruses Exhibit Differential Ferret Pathogenesis and Transmission Phenotypes.

PubMed

Pulit-Penaloza, Joanna A; Jones, Joyce; Sun, Xiangjie; Jang, Yunho; Thor, Sharmi; Belser, Jessica A; Zanders, Natosha; Creager, Hannah M; Ridenour, Callie; Wang, Li; Stark, Thomas J; Garten, Rebecca; Chen, Li-Mei; Barnes, John; Tumpey, Terrence M; Wentworth, David E; Maines, Taronna R; Davis, C Todd

2018-06-01

Influenza A(H1) viruses circulating in swine represent an emerging virus threat, as zoonotic infections occur sporadically following exposure to swine. A fatal infection caused by an H1N1 variant (H1N1v) virus was detected in a patient with reported exposure to swine and who presented with pneumonia, respiratory failure, and cardiac arrest. To understand the genetic and phenotypic characteristics of the virus, genome sequence analysis, antigenic characterization, and ferret pathogenesis and transmissibility experiments were performed. Antigenic analysis of the virus isolated from the fatal case, A/Ohio/09/2015, demonstrated significant antigenic drift away from the classical swine H1N1 variant viruses and H1N1 pandemic 2009 viruses. A substitution in the H1 hemagglutinin (G155E) was identified that likely impacted antigenicity, and reverse genetics was employed to understand the molecular mechanism of antibody escape. Reversion of the substitution to 155G, in a reverse genetics A/Ohio/09/2015 virus, showed that this residue was central to the loss of hemagglutination inhibition by ferret antisera raised against a prototypical H1N1 pandemic 2009 virus (A/California/07/2009), as well as gamma lineage classical swine H1N1 viruses, demonstrating the importance of this residue for antibody recognition of this H1 lineage. When analyzed in the ferret model, A/Ohio/09/2015 and another H1N1v virus, A/Iowa/39/2015, as well as A/California/07/2009, replicated efficiently in the respiratory tract of ferrets. The two H1N1v viruses transmitted efficiently among cohoused ferrets, but respiratory droplet transmission studies showed that A/California/07/2009 transmitted through the air more efficiently. Preexisting immunity to A/California/07/2009 did not fully protect ferrets from challenge with A/Ohio/09/2015. IMPORTANCE Human infections with classical swine influenza A(H1N1) viruses that circulate in pigs continue to occur in the United States following exposure to swine. To understand the genetic and virologic characteristics of a virus (A/Ohio/09/2015) associated with a fatal infection and a virus associated with a nonfatal infection (A/Iowa/39/2015), we performed genome sequence analysis, antigenic testing, and pathogenicity and transmission studies in a ferret model. Reverse genetics was employed to identify a single antigenic site substitution (HA G155E) responsible for antigenic variation of A/Ohio/09/2015 compared to related classical swine influenza A(H1N1) viruses. Ferrets with preexisting immunity to the pandemic A(H1N1) virus were challenged with A/Ohio/09/2015, demonstrating decreased protection. These data illustrate the potential for currently circulating swine influenza viruses to infect and cause illness in humans with preexisting immunity to H1N1 pandemic 2009 viruses and a need for ongoing risk assessment and development of candidate vaccine viruses for improved pandemic preparedness. This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Antigenic characterization of H3 subtypes of avian influenza A viruses from North America

USGS Publications Warehouse

Bailey, Elizabeth; Long, Li-Pong; Zhao, Nan; Hall, Jeffrey S.; Baroch, John A; Nolting, Jaqueline; Senter, Lucy; Cunningham, Frederick L; Pharr, G Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J.; Wan, Xiu-Feng

2016-01-01

Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log 2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable.

Antigenic Characterization of H3 Subtypes of Avian Influenza A Viruses from North America.

PubMed

Bailey, Elizabeth; Long, Li-Ping; Zhao, Nan; Hall, Jeffrey S; Baroch, John A; Nolting, Jacqueline; Senter, Lucy; Cunningham, Frederick L; Pharr, G Todd; Hanson, Larry; Slemons, Richard; DeLiberto, Thomas J; Wan, Xiu-Feng

2016-05-01

Besides humans, H3 subtypes of influenza A viruses (IAVs) can infect various animal hosts, including avian, swine, equine, canine, and sea mammal species. These H3 viruses are both antigenically and genetically diverse. Here, we characterized the antigenic diversity of contemporary H3 avian IAVs recovered from migratory birds in North America. Hemagglutination inhibition (HI) assays were performed on 37 H3 isolates of avian IAVs recovered from 2007 to 2011 using generated reference chicken sera. These isolates were recovered from samples taken in the Atlantic, Mississippi, Central, and Pacific waterfowl migration flyways. Antisera to all the tested H3 isolates cross-reacted with each other and, to a lesser extent, with those to H3 canine and H3 equine IAVs. Antigenic cartography showed that the largest antigenic distance among the 37 avian IAVs is about four units, and each unit corresponds to a 2 log 2 difference in the HI titer. However, none of the tested H3 IAVs cross-reacted with ferret sera derived from contemporary swine and human IAVs. Our results showed that the H3 avian IAVs we tested lacked significant antigenic diversity, and these viruses were antigenically different from those circulating in swine and human populations. This suggests that H3 avian IAVs in North American waterfowl are antigenically relatively stable.

Use of an Sm-p80–Based Therapeutic Vaccine to Kill Established Adult Schistosome Parasites in Chronically Infected Baboons

PubMed Central

Karmakar, Souvik; Zhang, Weidong; Ahmad, Gul; Torben, Workineh; Alam, Mayeen U.; Le, Loc; Damian, Raymond T.; Wolf, Roman F.; White, Gary L.; Carey, David W.; Carter, Darrick; Reed, Steven G.; Siddiqui, Afzal A.

2014-01-01

No vaccines are available for human use for any parasitic infections, including the helminthic disease schistosomiasis. Sm-p80, the large subunit of Schistosoma mansoni calpain, is a leading antigen candidate for a schistosomiasis vaccine. Prophylactic and antifecundity efficacies of Sm-p80 have been tested using a variety of vaccine approaches in both rodent and nonhuman primate models. However, the therapeutic efficacy of a Sm-p80–based vaccine had not been determined. In this study, we evaluated the therapeutic efficacy of Sm-p80 by using 2 different strategies and 3 Sm-p80–based vaccine formulations in baboons. Vaccine formulations were able to decrease established adult worms by 10%–36%, reduce retention of eggs in tissues by 10%–57%, and decrease egg excretion in feces by 13%–33%, compared with control formulations. Marked differences were observed in B and T cell immune correlates between vaccinated and control animals. This is the first report of killing of established adult schistosome worms by a vaccine. In addition to distinct prophylactic efficacy of Sm-p80, this study adds to the evidence that Sm-p80 is a potentially important antigen with both substantial prophylactic and therapeutic efficacies. These data reinforce that Sm-p80 should be moved forward along the path toward human clinical trials. PMID:24436452

Effects of Fab' fragments of specific egg yolk antibody (IgY-Fab') against Shewanella putrefaciens on the preservation of refrigerated turbot.

PubMed

Zhang, Qian; Lin, Hong; Sui, Jianxin; Wang, Jingxue; Cao, Limin

2015-01-01

In our previous studies the specific egg yolk antibody (IgY) against Shewanella putrefaciens (one of the specific spoilage organisms for marine products during aerobic chilling storage) demonstrated significant activity to prolong the shelf life of refrigerated fish. The exploitation of the antigen-binding fragment plus the hinge region (IgY-Fab') is now considered a promising method for improving the efficiency of such natural antimicrobial agents. The antimicrobial activity of IgY-Fab' against S. putrefaciens was investigated using refrigerated turbot as samples. By microbial, chemical and sensory tests, it was shown to be able to effectively inhibit bacterial growth and prolong the shelf life of samples, with an efficiency evaluated significantly higher than that of whole IgY with the same molarity. The interaction between IgY agents and S. putrefaciens cells was also investigated, and the IgY-Fab' showed a much greater ability to damage cell membranes than the whole IgY. Compared to whole IgY with the same molarity, IgY-Fab' demonstrated higher and more durable antimicrobial efficiency. Such a result was assumed to be closely related to its structural properties (such as the much lower molecular weight), which may enhance its ability to influence physiological activities of antigen bacteria, especially the property or/and structure of cell membranes. © 2014 Society of Chemical Industry.

Production, Characterization and Applications for Toxoplasma gondii-Specific Polyclonal Chicken Egg Yolk Immunoglobulins

PubMed Central

Ferreira Júnior, Álvaro; Santiago, Fernanda M.; Silva, Murilo V.; Ferreira, Flávia B.; Macêdo Júnior, Arlindo G.; Mota, Caroline M.; Faria, Matheus S.; Filho, Hercílio H. Silva; Silva, Deise A. O.; Cunha-Júnior, Jair P.; Mineo, José R.; Mineo, Tiago W. P.

2012-01-01

Background Toxoplasma gondii may cause abortions, ocular and neurological disorders in warm-blood hosts. Immunized mammals are a wide source of hyperimmune sera used in different approaches, including diagnosis and the study of host-parasite interactions. Unfortunately, mammalian antibodies present limitations for its production, such as the necessity for animal bleeding, low yield, interference with rheumatoid factor, complement activation and affinity to Fc mammalian receptors. IgY antibodies avoid those limitations; therefore they could be an alternative to be applied in T. gondii model. Methodology/Principal Findings In this study we immunized hens with soluble tachyzoite antigens of T. gondii (STAg) and purified egg yolk antibodies (IgY) by an inexpensive and simple method, with high yield and purity degree. IgY anti-STAg antibodies presented high avidity and were able to recognize a broad range of parasite antigens, although some marked differences were observed in reactivity profile between antibodies produced in immunized hens and mice. Interestingly, IgY antibodies against Neospora caninum and Eimeria spp. did not react to STAg. We also show that IgY antibodies were suitable to detect T. gondii forms in paraffin-embedded sections and culture cell monolayers. Conclusions/Significance Due to its cost-effectiveness, high production yield and varied range of possible applications, polyclonal IgY antibodies are useful tools for studies involving T. gondii. PMID:22808150

Vaccination with Killed but Metabolically Active E. coli Over-expressing Hemagglutinin Elicits Neutralizing Antibodies to H1N1 Swine Origin Influenza A Virus

PubMed Central

Liu, Pei-Feng; Wang, Yanhan; Liu, Yu-Tsueng; Huang, Chun-Ming

2017-01-01

There is a need for a fast and simple method for vaccine production to keep up with the pace of a rapidly spreading virus in the early phases of the influenza pandemic. The use of whole viruses produced in chicken eggs or recombinant antigens purified from various expression systems has presented considerable challenges, especially with lengthy processing times. Here, we use the killed but metabolically active (KBMA) Escherichia coli (E. coli) to harbor the hemagglutinin (HA) of swine origin influenza A (H1N1) virus (S-OIV) San Diego/01/09 (SD/H1N1-S-OIV). Intranasal vaccination of mice with KBMA E. coli SD/H1N1-S-OIV HA without adding exogenous adjuvants provoked detectable neutralizing antibodies against the virus-induced hemagglutination within three weeks. Boosting vaccination enhanced the titers of neutralizing antibodies, which can decrease viral infectivity in Madin-Darby canine kidney (MDCK) cells. The antibodies were found to specifically neutralize the SD/H1N1-S-OIV-, but not seasonal influenza viruses (H1N1 and H3N2), -induced hemagglutination. The use of KBMA E. coli as an egg-free system to produce anti-influenza vaccines makes unnecessary the rigorous purification of an antigen prior to immunization, providing an alternative modality to combat influenza virus in future outbreaks. PMID:28492063

[Various immunological aspects of essential and symptomatic hypertension].

PubMed

Shkhvatsabaia, I K; Rudnev, V I; Suvorov, Iu I; Domba, G Iu; Osipov, S G

1988-01-01

131 patients with essential hypertension (EH) and 30 patients with secondary hypertension (SH) of renal genesis were examined, all of them Russian inhabitants of Moscow, aged 20-56. In patients with EH increased rate of HLA-B13 and B22 antigens was determined. The highest rate of HLA-B13 antigen in this group was registered in patients without IHD, while patients with IHD had the highest rate of HLA-B22 antigen compared to controls. Patients with SH demonstrated no significant difference in HLA antigens distribution from that in controls. Besides, patients with EH had significantly increased serum concentration of circulating immune complexes (CIC), of IgA and beta 2-microglobulins as well as of three complement components (C3c, C4 and B factor). Similar changes were observed in patients with SH, excluding CIC and C3c, concentration of which did not differ from that in the control group. No strict dependence between the level of immunity humoral factors and presence of HLA-B13 and -B22 antigens was observed. The data gained suggest possible association of HLA system with EH development.

A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines.

PubMed

Laws, Thomas R; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F; Webster, Wendy M; Debes, Amanda K; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G; Tsanava, Shota; Dyson, Edward H; Simpson, Andrew J H; Hepburn, Matthew J; Trapaidze, Nino

2016-01-01

Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens.

Inactivation of Salmonella in Shell Eggs by Hot Water Immersion and Its Effect on Quality.

PubMed

Geveke, David J; Gurtler, Joshua B; Jones, Deana R; Bigley, Andrew B W

2016-03-01

Thermal inactivation kinetics of heat resistant strains of Salmonella Enteritidis in shell eggs processed by hot water immersion were determined and the effects of the processing on egg quality were evaluated. Shell eggs were inoculated with a composite of heat resistant Salmonella Enteritidis (SE) strains PT8 C405, 2 (FSIS #OB030832), and 6 (FSIS #OB040159). Eggs were immersed in a circulating hot water bath for various times and temperatures. Come-up time of the coldest location within the egg was 21 min. SE was reduced by 4.5 log at both hot water immersion treatments of 56.7 C for 60 min and 55.6 °C for 100 min. Decimal reduction times (D-values) at 54.4, 55.6, and 56.7 °C were 51.8, 14.6, and 9.33 min, respectively. The z-value was 3.07 °C. Following treatments that resulted in a 4.5 log reduction (56.7 °C/60 min and 55.6 °C/100 min), the surviving population of SE remained static during 4 wk of refrigerated storage. After processing under conditions resulting in 4.5 log reductions, the Haugh unit and albumen height significantly increased (P < 0.01) and yolk index significantly decreased (P < 0.05). The shell dynamic stiffness significantly increased (P < 0.05), while static compression shell strength showed no significant difference (P < 0.05). Vitelline membrane strength significantly increased (P < 0.05); although, no significant difference (P < 0.05) was observed in vitelline membrane elasticity. In summary, the hot water immersion process inactivated heat resistant SE in shell eggs by 4.5 log, but also significantly affected several egg quality characteristics. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Epidemiological and Virological Characteristics of Influenza Viruses Circulating in Cambodia from 2009 to 2011

PubMed Central

Ly, Sovann; Heng, Seng; Vong, Sirenda; Kitsutani, Paul; Ieng, Vannra; Tarantola, Arnaud; Ly, Sowath; Sar, Borann; Chea, Nora; Sokhal, Buth; Barr, Ian; Kelso, Anne; Horwood, Paul F.; Timmermans, Ans; Hurt, Aeron; Lon, Chanthap; Saunders, David; Ung, Sam An; Asgari, Nima; Roces, Maria Concepcion; Touch, Sok; Komadina, Naomi; Buchy, Philippe

2014-01-01

Background The Cambodian National Influenza Center (NIC) monitored and characterized circulating influenza strains from 2009 to 2011. Methodology/Principal Findings Sentinel and study sites collected nasopharyngeal specimens for diagnostic detection, virus isolation, antigenic characterization, sequencing and antiviral susceptibility analysis from patients who fulfilled case definitions for influenza-like illness, acute lower respiratory infections and event-based surveillance. Each year in Cambodia, influenza viruses were detected mainly from June to November, during the rainy season. Antigenic analysis show that A/H1N1pdm09 isolates belonged to the A/California/7/2009-like group. Circulating A/H3N2 strains were A/Brisbane/10/2007-like in 2009 before drifting to A/Perth/16/2009-like in 2010 and 2011. The Cambodian influenza B isolates from 2009 to 2011 all belonged to the B/Victoria lineage represented by the vaccine strains B/Brisbane/60/2008 and B/Malaysia/2506/2004. Sequences of the M2 gene obtained from representative 2009–2011 A/H3N2 and A/H1N1pdm09 strains all contained the S31N mutation associated with adamantanes resistance except for one A/H1N1pdm09 strain isolated in 2011 that lacked this mutation. No reduction in the susceptibility to neuraminidase inhibitors was observed among the influenza viruses circulating from 2009 to 2011. Phylogenetic analysis revealed that A/H3N2 strains clustered each year to a distinct group while most A/H1N1pdm09 isolates belonged to the S203T clade. Conclusions/Significance In Cambodia, from 2009 to 2011, influenza activity occurred throughout the year with peak seasonality during the rainy season from June to November. Seasonal influenza epidemics were due to multiple genetically distinct viruses, even though all of the isolates were antigenically similar to the reference vaccine strains. The drug susceptibility profile of Cambodian influenza strains revealed that neuraminidase inhibitors would be the drug of choice for influenza treatment and chemoprophylaxis in Cambodia, as adamantanes are no longer expected to be effective. PMID:25340711

Thyroid hormone regulates vitellogenin by inducing estrogen receptor alpha in the goldfish liver.

PubMed

Nelson, Erik R; Habibi, Hamid R

2016-11-15

Vitellogenin (Vtg) is an egg-yolk precursor protein that is synthesized in the liver of oviparous species and taken up from the circulation by the ovary. It is well known that Vtg is induced by circulating estrogens. However, other endocrine factors that regulate the expression of Vtg are less well characterized; factors that might play significant roles, especially in seasonal spawners such as the goldfish which require increased quantities of Vtg for the development of hundreds of follicles. In this regard, thyroid hormones have been shown to cycle with the reproductive season. Therefore, we hypothesized that the thyroid hormones might influence the synthesis of Vtg. Treatment of female goldfish with triiodothyronine (T3) resulted in increased Vtg, an observation that was absent in males. Furthermore, T3 failed to induce Vtg in cultured hepatocytes of either sex. Interestingly however, T3 consistently up-regulated the expression of the estrogen receptor alpha (ERα). The T3 mediated upregulation of ERα requires the presence of both thyroid receptor (TR) α-1 and TRβ. When goldfish or cultured hepatocytes were treated with T3 followed by estradiol, there was a synergistic increase in Vtg, a response which is dependent on the presence of ERα. Therefore, by upregulating ERα, T3 serves to prime the liver to subsequent stimuli from estradiol. This cross-talk likely reveals an important physiologic mechanism by which thyroid hormones, whose circulating levels are high during early gonadal recrudescence, facilitate the production of large amounts of Vtg required for egg development. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Low incidence of N-glycolylneuraminic acid in birds and reptiles and its absence in the platypus.

PubMed

Schauer, Roland; Srinivasan, G Vinayaga; Coddeville, Bernadette; Zanetta, Jean-Pierre; Guérardel, Yann

2009-08-17

The sialic acids of the platypus, birds, and reptiles were investigated with regard to the occurrence of N-glycolylneuraminic (Neu5Gc) acid. They were released from tissues, eggs, or salivary mucin samples by acid hydrolysis, and purified and analyzed by thin-layer chromatography, high-performance liquid chromatography, and mass spectrometry. In muscle and liver of the platypus only N-acetylneuraminic (Neu5Ac) acid was found. The nine bird species studied also did not express N-glycolylneuraminic acid with the exception of an egg, but not tissues, from the budgerigar and traces in poultry. Among nine reptiles, including one turtle, N-glycolylneuraminic acid was only found in the egg and an adult basilisk, but not in a freshly hatched animal. BLAST analysis of the genomes of the platypus, the chicken, and zebra finch against the CMP-N-acetylneuraminic acid hydroxylase did not reveal the existence of a similar protein structure. Apparently monotremes (platypus) and sauropsids (birds and reptiles) cannot synthesize Neu5Gc. The few animals where Neu5Gc was found, especially in eggs, may have acquired this from the diet or by an alternative pathway. Since Neu5Gc is antigenic to man, the observation that this monosaccharide does not or at least only rarely occur in birds and reptiles, may be of nutritional and clinical significance.

Respiratory Syncytial Virus (RSV) Infects CD4+ T Cells: Frequency of Circulating CD4+ RSV+ T Cells as a Marker of Disease Severity in Young Children.

PubMed

Raiden, Silvina; Sananez, Inés; Remes-Lenicov, Federico; Pandolfi, Julieta; Romero, Cecilia; De Lillo, Leonardo; Ceballos, Ana; Geffner, Jorge; Arruvito, Lourdes

2017-04-01

Although human airway epithelial cells are the main target of respiratory syncytial virus (RSV), it also infects immune cells, such as macrophages and B cells. Whether T cells are permissive to RSV infection is unknown. We sought to analyze the permissiveness of CD4+ T cells to RSV infection. CD4+ and CD8+ T cells from cord blood, healthy young children, and adults were challenged by RSV or cocultured with infected HEp-2 cells. Infection, phenotype, and cytokine production by T cells were analyzed by flow cytometry or enzyme-linked immunosorbent assay. Expression of RSV antigens by circulating CD4+ T cells from infected children was analyzed by flow cytometry, and disease severity was defined by standard criteria. CD4+ and CD8+ T cells were productively infected by RSV. Infection decreased interleukin 2 and interferon γ production as well as the expression of CD25 and Ki-67 by activated CD4+ T cells. Respiratory syncytial virus antigens were detected in circulating CD4+ and CD8+ T cells during severe RSV infection of young children. Interestingly, the frequency of CD4+ RSV+ T cells positively correlated with disease severity. Respiratory syncytial virus infects CD4+ and CD8+ T cells and compromises T-cell function. The frequency of circulating CD4+ RSV+ T cells might represent a novel marker of severe infection. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

Substitutions near the Hemagglutinin Receptor-Binding Site Determine the Antigenic Evolution of Influenza A H3N2 Viruses in U.S. Swine

PubMed Central

Lewis, Nicola S.; Anderson, Tavis K.; Kitikoon, Pravina; Skepner, Eugene; Burke, David F.

2014-01-01

ABSTRACT Swine influenza A virus is an endemic and economically important pathogen in pigs, with the potential to infect other host species. The hemagglutinin (HA) protein is the primary target of protective immune responses and the major component in swine influenza A vaccines. However, as a result of antigenic drift, vaccine strains must be regularly updated to reflect currently circulating strains. Characterizing the cross-reactivity between strains in pigs and seasonal influenza virus strains in humans is also important in assessing the relative risk of interspecies transmission of viruses from one host population to the other. Hemagglutination inhibition (HI) assay data for swine and human H3N2 viruses were used with antigenic cartography to quantify the antigenic differences among H3N2 viruses isolated from pigs in the United States from 1998 to 2013 and the relative cross-reactivity between these viruses and current human seasonal influenza A virus strains. Two primary antigenic clusters were found circulating in the pig population, but with enough diversity within and between the clusters to suggest updates in vaccine strains are needed. We identified single amino acid substitutions that are likely responsible for antigenic differences between the two primary antigenic clusters and between each antigenic cluster and outliers. The antigenic distance between current seasonal influenza virus H3 strains in humans and those endemic in swine suggests that population immunity may not prevent the introduction of human viruses into pigs, and possibly vice versa, reinforcing the need to monitor and prepare for potential incursions. IMPORTANCE Influenza A virus (IAV) is an important pathogen in pigs and humans. The hemagglutinin (HA) protein is the primary target of protective immune responses and the major target of vaccines. However, vaccine strains must be updated to reflect current strains. Characterizing the differences between seasonal IAV in humans and swine IAV is important in assessing the relative risk of interspecies transmission of viruses. We found two primary antigenic clusters of H3N2 in the U.S. pig population, with enough diversity to suggest updates in swine vaccine strains are needed. We identified changes in the HA protein that are likely responsible for these differences and that may be useful in predicting when vaccines need to be updated. The difference between human H3N2 viruses and those in swine is enough that population immunity is unlikely to prevent new introductions of human IAV into pigs or vice versa, reinforcing the need to monitor and prepare for potential introductions. PMID:24522915

Functional restoration of HCV-specific CD8 T cells by PD-1 blockade is defined by PD-1 expression and compartmentalization.

PubMed

Nakamoto, Nobuhiro; Kaplan, David E; Coleclough, Jennifer; Li, Yun; Valiga, Mary E; Kaminski, Mary; Shaked, Abraham; Olthoff, Kim; Gostick, Emma; Price, David A; Freeman, Gordon J; Wherry, E John; Chang, Kyong-Mi

2008-06-01

The immunoinhibitory receptor programmed death-1 (PD-1) is up-regulated on dysfunctional virus-specific CD8 T cells during chronic viral infections, and blockade of PD-1/PD-ligand (PD-L) interactions can restore their function. As hepatitis C virus (HCV) persists in the liver with immune-mediated disease pathogenesis, we examined the role of PD-1/PD-L pathway in antigen-specific CD8 T-cell dysfunction in the liver and blood of HCV-infected patients. PD-1 expression and function of circulating CD8 T cells specific for HCV, Epstein-Barr virus, and influenza virus were examined ex vivo and following antigenic stimulation in vitro in patients with acute, chronic, and resolved HCV infection using class I tetramers and flow cytometry. Intrahepatic CD8 T cells were examined from liver explants of chronically HCV-infected transplant recipients. Intrahepatic HCV-specific CD8 T cells from chronically HCV-infected patients were highly PD-1 positive, profoundly dysfunctional, and unexpectedly refractory to PD-1/PD-L blockade, contrasting from circulating PD-1-intermediate HCV-specific CD8 T cells with responsiveness to PD-1/PD-L blockade. This intrahepatic functional impairment was HCV-specific and directly associated with the level of PD-1 expression. Highly PD-1-positive intrahepatic CD8 T cells were more phenotypically exhausted with increased cytotoxic T-lymphocyte antigen 4 and reduced CD28 and CD127 expression, suggesting that active antigen-specific stimulation in the liver induces a profound functional exhaustion not reversible by PD-1/PD-L blockade alone. HCV-specific CD8 T-cell dysfunction and responsiveness to PD-1/PD-L blockade are defined by their PD-1 expression and compartmentalization. These findings provide new and clinically relevant insight to differential antigen-specific CD8 T-cell exhaustion and their functional restoration.

Functional restoration of HCV-specific CD8 T-cells by PD1 blockade is defined by PD1 expression and compartmentalization

PubMed Central

Nakamoto, Nobuhiro; Kaplan, David E.; Coleclough, Jennifer; Li, Yun; Kaminski, Mary; Shaked, Abraham; Olthoff, Kim; Gostick, Emma; Price, David A.; Freeman, Gordon J.; Wherry, E. John; Chang, Kyong-Mi

2008-01-01

Background & Aims The immuno-inhibitory receptor Programmed Death-1 (PD-1) is upregulated on dysfunctional virus-specific CD8 T-cells during chronic viral infections and blockade of PD-1:PD-ligand (PD-L) interactions can restore their function. As hepatitis C virus (HCV) persists in the liver with immune-mediated disease pathogenesis, we examined the role of PD1/PD-L pathway in antigen-specific CD8 T-cell dysfunction in the liver and blood of HCV-infected patients. Methods PD-1 expression and function of circulating CD8 T-cells specific for HCV, EBV and Flu were examined ex vivo and following antigenic stimulation in vitro in patients with acute, chronic and resolved HCV infection using class I tetramers and flow cytometry. Intrahepatic CD8 T-cells were examined from liver explants of chronically HCV-infected transplant recipients. Results Intrahepatic HCV-specific CD8 T-cells from chronically HCV-infected patients were highly PD-1-positive, profoundly dysfunctional and unexpectedly refractory to PD-1:PD-L blockade, contrasting from circulating PD-1-intermediate HCV-specific CD8 T-cells with responsiveness to PD-1:PD-L blockade. This intrahepatic functional impairment was HCV-specific and directly associated with the level of PD-1 expression. Highly PD-1-positive intrahepatic CD8 T-cells were more phenotypically exhausted with increased cytotoxic T-lymphocyte antigen 4 (CTLA-4) and reduced CD28 and CD127 expression, suggesting that active antigen-specific stimulation in the liver induces a profound functional exhaustion not reversible by PD-1:PD-L blockade alone. Conclusion HCV-specific CD8 T-cell dysfunction and responsiveness to PD-1:PD-L blockade are defined by their PD-1 expression and compartmentalization. These findings provide new and clinically relevant insight to differential antigen-specific CD8 T-cell exhaustion and their functional restoration. PMID:18549878

Phylogenetic, antigenic and biological characterization of pigeon paramyxovirus type 1 circulating in China.

PubMed

Qiu, Xusheng; Meng, Chunchun; Zhan, Yuan; Yu, Shengqing; Li, Shichao; Ren, Tingting; Yuan, Weifeng; Xu, Shuqin; Sun, Yingjie; Tan, Lei; Song, Cuiping; Liao, Ying; Ding, Zhuang; Liu, Xiufan; Ding, Chan

2017-09-29

For many years, ND has been one of the most important infectious pigeon diseases in China. In recent years, a high mortality has been observed in ND-infected pigeons in China. Mortality is from 40% to 80% or 100% in some cases. The full-length genomes of four pigeon paramyxovirus type 1 (PPMV-1) strains, which were isolated from infected pigeons in China in 2012 and 2013, were sequenced and analyzed to determine the phylogenetic characteristics of PPMV-1 circulating in pigeons of China in recent years. Furthermore, cross hemagglutination inhibition and cross virus neutralization assays, as well as animal experiments were conducted to determine the antigenicity and pathogenicity of those viruses. Proteolytic cleavage sites (residues 112-117) of the F proteins were identified as the typical virulence motif, 112 RRQKR↓F 117 for all four PPMV-1 strains investigated. Phylogenetic analysis based on sequences of complete genomes and F gene revealed that the four PPMV-1 isolates and most of recent isolates in China were highly homologous to European isolates from 1998 to 2011. All those isolates were clustered in one clade of genotype VI NDV, termed as subgroup 4bii f. The R value was calculated based on cross hemagglutination inhibition and cross virus neutralization results, and confirmed antigenic difference of the PPMV-1 strains isolated in 2013 from the LaSota vaccine strain. Several mutations were identified in the surface glycoproteins F and HN, which probably gave rise to those antigenic differences. Our result suggested that the PPMV-1 strain prevailing in China in the last decade diverged from a common ancestor and was presumably transmitted from Europe. PPMV-1 isolates displayed obvious antigenic differences from vaccine strain LaSota. Even though PPMV-1 did not cause high mortality in experimental pigeons, the infected pigeons were exhibiting viral shedding for 3 weeks after infection, suggesting PPMV-1 is a potential threat to NDV control worldwide.

Comparative characteristics of the VP7 and VP4 antigenic epitopes of the rotaviruses circulating in Russia (Nizhny Novgorod) and the Rotarix and RotaTeq vaccines.

PubMed

Morozova, O V; Sashina, T A; Fomina, S G; Novikova, N A

2015-07-01

Two live, attenuated rotavirus A (RVA) vaccines, Rotarix and RotaTeq, have been successfully introduced into national immunization programs worldwide. The parent strains of both vaccines were obtained more than 30 years ago. Nonetheless, only very limited data are available on the molecular similarity of the vaccine strains and their genetic relationships to the wild-type strains circulating within the territory of Russian Federation. In this study, we have determined the nucleotide sequences of the genes encoding the viral proteins VP7 and VP4 (the globular domain VP8*) of vaccine strains and natural isolates of rotaviruses in Nizhny Novgorod, Russia. The VP7 and VP4 proteins contain antigenic sites that are the main targets of neutralizing antibodies. Phylogenetic analysis based on VP4 and VP7 showed that the majority of the natural RVA isolates from Nizhny Novgorod and the vaccine strains belong to different clusters. Four amino acids within the VP7 antigenic sites were common in both the wild-type and vaccine strains. The largest number of amino acid differences was found between the vaccine strain Rotarix and the Nizhny Novgorod G2 strains (19 residues out of 29). From 3 to 5 amino acid differences per strain were identified in the antigenic sites of VP4 (domain VP8*) between wild-type strains and the vaccine RotaTeq, and 6-8 substitutions were found when they were compared with the vaccine strain Rotarix. For the first time, immunodominant T-cell epitopes of VP7 were analyzed, and differences in the sequences between the vaccine and the wild-type strains were found. The accumulation of amino acid substitutions in the VP7 and VP4 antigenic sites may potentially reduce the immune protection of vaccinated children from wild-type strains of rotavirus.

Novel reassortant H9N2 viruses in pigeons and evidence for antigenic diversity of H9N2 viruses isolated from quails in Egypt

PubMed Central

Kandeil, Ahmed; El-Shesheny, Rabeh; Maatouq, Asmaa; Moatasim, Yassmin; Cai, Zhipeng; McKenzie, Pamela; Webby, Richard

2017-01-01

The endemicity of avian influenza viruses (AIVs) among Egyptian poultry represents a public health risk. Co-circulation of low pathogenic AIV H9N2 subtype with highly pathogenic AIV H5N1 subtype in Egyptian farms provides a possibility to generate novel reassortant viruses. Here, the genetic characteristics of surface glycoproteins of 59 Egyptian H9N2 viruses, isolated between 2013 and 2015, were analysed. To elucidate the potential of genetic reassortment, 10 H9N2 isolates were selected based on different avian hosts (chickens, ducks, pigeons and quails) and phylogenetic analyses of their full genome sequences were conducted. Additionally, we performed antigenic analysis to further investigate the antigenic evolution of H9N2 viruses isolated during 2011–2015. Different viral characteristics including receptor-binding affinity and drug resistance of representative Egyptian H9N2 viruses were further investigated. The surface glycoproteins of current Egyptian H9N2 viruses were closely related to viruses of the G1-like lineage isolated from Egypt. Several genetic markers that enhance virulence in poultry and transmission to humans were detected. Analysis of the full genome of 10 H9N2 isolates indicated that two pigeon isolates inherited five internal genes from Eurasian AIVs circulating in wild birds. Antigenic conservation of different Egyptian H9N2 isolates from chickens, pigeons and ducks was observed, whereas quail isolates showed antigenic drift. The Egyptian H9N2 viruses preferentially bound to the human-like receptor rather than to the avian-like receptor. Our results suggest that the endemic H9N2 viruses in Egypt contain elements that may favour avian-to-human transmission and thus represent a public health risk. PMID:27902350

Measurement of Circulating Filarial Antigen Levels in Human Blood with a Point-of-Care Test Strip and a Portable Spectrodensitometer

PubMed Central

Chesnais, Cédric B.; Vlaminck, Johnny; Kunyu-Shako, Billy; Pion, Sébastien D.; Awaca-Uvon, Naomi-Pitchouna; Weil, Gary J.; Mumba, Dieudonné; Boussinesq, Michel

2016-01-01

The Alere Filariasis Test Strip (FTS) is a qualitative, point-of-care diagnostic tool that detects Wuchereria bancrofti circulating filarial antigen (CFA) in human blood, serum, or plasma. The Global Program to Eliminate Lymphatic Filariasis employs the FTS for mapping filariasis-endemic areas and assessing the success of elimination efforts. The objective of this study was to explore the relationship between the intensity of positive test lines obtained by FTS with CFA levels as determined by enzyme-linked immunosorbent assay (ELISA) with blood and plasma samples from 188 individuals who live in a filariasis-endemic area. The intensity of the FTS test line was assessed visually to provide a semiquantitative score (visual Filariasis Test Strip [vFTS]), and line intensity was measured with a portable spectrodensitometer (quantitative Filariasis Test Strip [qFTS]). These results were compared with antigen levels measured by ELISA in plasma from the same subjects. qFTS measurements were highly correlated with vFTS scores (ρ = 0.94; P < 0.001) and with plasma CFA levels (ρ = 0.91; P < 0.001). Thus, qFTS assessment is a convenient method for quantifying W. bancrofti CFA levels in human blood, which are correlated with adult worm burdens. This tool may be useful for assessing the impact of treatment on adult filarial worms in individuals and communities. PMID:27114288

Single gene reassortment of highly pathogenic avian influenza A H5N1 in the low pathogenic H9N2 backbone and its impact on pathogenicity and infectivity of novel reassortant viruses.

PubMed

Moatasim, Yassmin; Kandeil, Ahmed; Mostafa, Ahmed; Elghaffar, Sary Khaleel Abd; El Shesheny, Rabeh; Elwahy, Ahmed Helmy M; Ali, Mohamed Ahmed

2017-10-01

Avian influenza A H5N1 and H9N2 viruses have been extensively circulating in various avian species and frequently infect mammals, including humans. The synchronous circulation of both viruses in Egypt provides an opportunity for possible genetic assortment, posing a probable threat to global public health. To assess the potential risk of the IAV reassortants derived from co-circulation of these two AI subtypes, reverse genetics technology was used to generate a set of IAV reassortants carrying single genetic segments of clade 2.2.1.2 virus A/duck/Egypt/Q4596D/2012 (H5N1), a representative of the most prevalent H5N1 clade in Egypt, in the genetic backbone of A/chicken/Egypt/S4456B/2011 (H9N2), a representative of G1-like H9N2 lineage which is widely circulating in Egypt. Furthermore, the genetic compatibility, growth kinetics and virulence were evaluated in vitro in mammalian systems using the MDCK cell line and avian system using SPF embryonated chicken eggs. Pathogenicity and virus shedding were further tested using SPF chickens. Out of the eight desired H9-reassortants, we could rescue only 5 reassortant viruses, either due to difficulty in cloning (PB1 of H5N1 virus) or genetic incompatibility (NP-H5/H9 and NA-H5/H9). Results revealed higher replication rates for the H9N2 virus having the NS segment of H5N1 virus. The lowest survival rate in both SPF eggs and SPF chickens was associated with the H5N1 parent virus infection, followed by the HA-H5/H9 virus. Our findings also suggest that all other reassortant viruses were of lower pathogenicity than the wild type H5N1 virus.

Specific Fluorine Labeling of the HyHEL10 Antibody Affects Antigen Binding and Dynamics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Acchione, Mauro; Lee, Yi-Chien; DeSantis, Morgan E.

To more fully understand the molecular mechanisms responsible for variations in binding affinity with antibody maturation, we explored the use of site specific fluorine labeling and {sup 19}F nuclear magnetic resonance (NMR). Several single-chain (scFv) antibodies, derived from an affinity-matured series of anti-hen egg white lysozyme (HEL) mouse IgG1, were constructed with either complete or individual replacement of tryptophan residues with 5-fluorotryptophan ({sup 5F}W). An array of biophysical techniques was used to gain insight into the impact of fluorine substitution on the overall protein structure and antigen binding. SPR measurements indicated that {sup 5F}W incorporation lowered binding affinity for themore » HEL antigen. The degree of analogue impact was residue-dependent, and the greatest decrease in affinity was observed when {sup 5F}W was substituted for residues near the binding interface. In contrast, corresponding crystal structures in complex with HEL were essentially indistinguishable from the unsubstituted antibody. {sup 19}F NMR analysis showed severe overlap of signals in the free fluorinated protein that was resolved upon binding to antigen, suggesting very distinct chemical environments for each {sup 5F}W in the complex. Preliminary relaxation analysis suggested the presence of chemical exchange in the antibody-antigen complex that could not be observed by X-ray crystallography. These data demonstrate that fluorine NMR can be an extremely useful tool for discerning structural changes in scFv antibody-antigen complexes with altered function that may not be discernible by other biophysical techniques.« less

Comparison of the changes of the antigenicities of a hen's egg albumin by a gamma and an electron beam irradiation

NASA Astrophysics Data System (ADS)

Lee, Ju-Woon; Seo, Ji-Hyun; Kim, Jae-Hun; Lee, Soo-Young; Byun, Myung-Woo

2007-05-01

The study was conducted to compare the radiation types of a gamma ray and an electron beam for the inhibition and reduction of a food allergy. OVA (2 mg/ml) were irradiated at 3, 5, 7 and 10 kGy. Patterns detected by the SDS-PAGE and an immunoblot showed that the intact OVA band disappeared and that it was dependant upon the radiation doses regardless of the radiation types. Binding abilities of the irradiated OVA against the monoclonal IgG and the egg allergic patients' IgE decreased due to a conformational change of the epitope, but differences from using the two different radiation types were not observed. The results indicate that both the radiation types can be used for an inhibition and a reduction of a food allergy regardless of the radiation types.

Initiation of DNA replication requires actin dynamics and formin activity.

PubMed

Parisis, Nikolaos; Krasinska, Liliana; Harker, Bethany; Urbach, Serge; Rossignol, Michel; Camasses, Alain; Dewar, James; Morin, Nathalie; Fisher, Daniel

2017-11-02

Nuclear actin regulates transcriptional programmes in a manner dependent on its levels and polymerisation state. This dynamics is determined by the balance of nucleocytoplasmic shuttling, formin- and redox-dependent filament polymerisation. Here, using Xenopus egg extracts and human somatic cells, we show that actin dynamics and formins are essential for DNA replication. In proliferating cells, formin inhibition abolishes nuclear transport and initiation of DNA replication, as well as general transcription. In replicating nuclei from transcriptionally silent Xenopus egg extracts, we identified numerous actin regulators, and disruption of actin dynamics abrogates nuclear transport, preventing NLS (nuclear localisation signal)-cargo release from RanGTP-importin complexes. Nuclear formin activity is further required to promote loading of cyclin-dependent kinase (CDK) and proliferating cell nuclear antigen (PCNA) onto chromatin, as well as initiation and elongation of DNA replication. Therefore, actin dynamics and formins control DNA replication by multiple direct and indirect mechanisms. © 2017 The Authors.

Identification, characterization, and quantitation of soluble HLA antigens in the circulation and peritoneal dialysate of renal patients.

PubMed Central

Gelder, F B; McDonald, J C; Landreneau, M D; McMillan, R M; Aultman, D F

1991-01-01

Human lymphocyte antigen (HLA) class I and class II antigens and beta 2 microglobulin (B2M) were identified in peritoneal dialysate (PD) and serum from patients with end-stage renal disease (ESRD) using monoclonal antibodies in an enzyme-linked immunoassay. The HLA class I and class II antigens each exhibited approximate molecular weights of 50,000 to 60,000 daltons by chromatography on Sepharose CL 6B. Class I antigens in serum and PD fluid were associated with B2M. Free B2M (Mr 11,500) also was detected in both sera and PD fluids. Unlike class I antigens, class II antigens were not found to have attached B2M. Class I and class II antigens eluted from 2-diethylaminoethanol ion exchange gradient columns at 0.07 mol/L (molar) phosphate buffer pH 7.2 and migrated with alpha 2-beta 1 mobility in agarose electrophoresis. Class I antigens were purified from ESRD patients' PD fluid by solid-phase immunoaffinity chromatography. Enzyme-linked immunoassay demonstrated that this purified protein was composed of a class I heavy chain and B2M. Class I allospecificity was confirmed by neutralization on known HLA typing antisera in a microcytotoxicity assay. Soluble HLA class I antigen preparations specifically inhibited blast transformation of responder lymphocytes in mixed lymphocyte culture reactions. Inhibition was dose dependent and ranged from 0% to 95%. The presence of soluble HLA antigens in body fluids may play an important part in the immunologic tolerance to self. This study demonstrates a ready source of large quantities of soluble HLA for detailed analysis. Images Fig. 1. PMID:2039290

The selective recognition of antibody IgY for digestive system cancers.

PubMed

Yang, J; Jin, Z; Yu, Q; Yang, T; Wang, H; Liu, L

1997-01-01

Biological methods for cancer therapies are very important. A small and efficient target carrier is the key component for anti-cancer drugs. In our laboratory, the antibody IgY was extracted from egg yolk of a SPF hen. The SPF hen was immunized with an antigene of P110 protein which was purified from human stomach cancer MGC-803 cells. Results indicated that the antibody IgY can specifically recognize gastrointestinal system cancers. It may become an important carrier for antitumorigenic drugs.

In vitro studies of chicken egg yolk antibody (IgY) against Salmonella enteritidis and Salmonella typhimurium.

PubMed

Lee, E N; Sunwoo, H H; Menninen, K; Sim, J S

2002-05-01

Chicken egg yolk antibody (IgY) raised against Salmonella enteritidis or Salmonella typhimurium was found in highly specific activity levels by ELISA. S. enteritidis- and S. typhimurium-specific IgY powder, prepared by freeze-drying the egg yolk water-soluble fraction, contained 15.5 and 10.0% of specific IgY, respectively. Anti-S. enteritidis IgY cross-reacted 55.3% with S. typhimurium. The cross-reactivity of anti-S. typhimurium IgY with S. enteritidis was 42.4%. Salmonella-specific IgY was demonstrated to inhibit Salmonella growth in liquid medium. The growth rate of S. enteritidis incubated with S. enteritidis-specific IgY was fourfold less than that of the control group during a 4-to-6-h incubation. Cell counts of S. typhimurium incubated with S. typhimurium-specific IgY were reduced by 1.6 log cfu/mL in comparison to that of the control group after 6 h of incubation. The specific binding activity of IgY was further evaluated by using immunofluorescence and immunoelectron microscopy. It was found that Salmonella-specific IgY could bind to the antigens expressed on the Salmonella surface, resulting in structural alterations of the bacterial surface.

Improving influenza virological surveillance in Europe: strain-based reporting of antigenic and genetic characterisation data, 11 European countries, influenza season 2013/14

PubMed Central

Broberg, Eeva; Hungnes, Olav; Schweiger, Brunhilde; Prosenc, Katarina; Daniels, Rod; Guiomar, Raquel; Ikonen, Niina; Kossyvakis, Athanasios; Pozo, Francisco; Puzelli, Simona; Thomas, Isabelle; Waters, Allison; Wiman, Åsa; Meijer, Adam

2016-01-01

Influenza antigenic and genetic characterisation data are crucial for influenza vaccine composition decision making. Previously, aggregate data were reported to the European Centre for Disease Prevention and Control by European Union/European Economic Area (EU/EEA) countries. A system for collecting case-specific influenza antigenic and genetic characterisation data was established for the 2013/14 influenza season. In a pilot study, 11 EU/EEA countries reported through the new mechanism. We demonstrated feasibility of reporting strain-based antigenic and genetic data and ca 10% of influenza virus-positive specimens were selected for further characterisation. Proportions of characterised virus (sub)types were similar to influenza virus circulation levels. The main genetic clades were represented by A/StPetersburg/27/2011(H1N1)pdm09 and A/Texas/50/2012(H3N2). A(H1N1)pdm09 viruses were more prevalent in age groups (by years) < 1 (65%; p = 0.0111), 20–39 (50%; p = 0.0046) and 40–64 (55%; p = 0.00001) while A(H3N2) viruses were most prevalent in those ≥ 65 years (62%*; p = 0.0012). Hospitalised patients in the age groups 6–19 years (67%; p = 0.0494) and ≥ 65 years (52%; p = 0.0005) were more frequently infected by A/Texas/50/2012 A(H3N2)-like viruses compared with hospitalised cases in other age groups. Strain-based reporting enabled deeper understanding of influenza virus circulation among hospitalised patients and substantially improved the reporting of virus characterisation data. Therefore, strain-based reporting of readily available data is recommended to all reporting countries within the EU/EEA. PMID:27762211

Prevalence and molecular epidemiology of Canine parvovirus 2 in diarrheic dogs in Colombia, South America: A possible new CPV-2a is emerging?

PubMed

Duque-García, Yeison; Echeverri-Zuluaga, Manuela; Trejos-Suarez, Juanita; Ruiz-Saenz, Julian

2017-03-01

Since its identification in 1978, Canine parvovirus type 2 (CPV-2) has been considered a pathogen of great importance in the canine population because it causes severe enteritis with high mortality rates in pups. CPV-2 is a virus belonging to the family Parvoviridae. Currently, there are three described antigenic variants (CPV-2a, CPV-2b, and CPV-2c). CPV-2c is an emerging virus that is seen as a global health hazard. The objective of this work was to confirm the presence of CPV-2 in dogs with acute gastroenteritis compatible with parvovirus and to molecularly characterize the antigenic variants circulating in two regions of Colombia. An analytical cross-sectional study was conducted with fecal samples collected from 71 dogs showing signs of acute diarrhea. The samples were processed and polymerase chain reaction (PCR), restriction fragment length polymorphism analysis (RFLP), sequencing and phylogenetic analysis was performed to detect and characterize CPV. A total of 70.42% of the individuals were confirmed positive for CPV-2. Statistically differences were found in the presentation of CPV-2 between the evaluated regions. Phylogenetic analyses confirmed the presence of the antigenic variants CPV-2a/2b. Moreover, we found the presence of two conserved substitutions Asn428Asp and Ala514Ser in the VP2 protein suggesting the presence of a possible new CPV-2a variant circulating in Colombia. This study demonstrates the importance of the CPV 2a/2b in the region and highlights the importance of performing molecular studies for the early detection of new antigenic variants of CPV-2. Copyright © 2017 Elsevier B.V. All rights reserved.

Transfer of allogeneic CD4+ T cells rescues CD8+ T cells in anti-PD-L1–resistant tumors leading to tumor eradication

PubMed Central

Arina, Ainhoa; Karrison, Theodore; Galka, Eva; Schreiber, Karin; Weichselbaum, Ralph R.; Schreiber, Hans

2017-01-01

Adoptively transferred CD8+ T cells can stabilize the size of solid tumors over long periods of time by exclusively recognizing antigen cross-presented on tumor stroma. However, these tumors eventually escape T cell–mediated growth control. The aim of this study was to eradicate such persistent cancers. In our model, the SIYRYYGL antigen is expressed by cancer cells that lack the MHC-I molecule Kb needed for direct presentation, but the antigen is picked up and cross-presented by tumor stroma. A single injection of antigen-specific 2C CD8+ T cells caused long-term inhibition of tumor growth, but without further intervention, tumors started to progress after approximately 3 months. Escape was associated with reduced numbers of circulating 2C cells. Tumor-infiltrating 2C cells produced significantly less TNFα and expressed more of the “exhaustion” markers PD-1 and Tim-3 than T cells from lymphoid organs. High-dose local ionizing radiation, depletion of myeloid-derived suppressor cells, infusions of additional 2C cells, and antibodies blocking PD-L1 did not prevent tumor escape. In contrast, adoptive transfer of allogeneic CD4+ T cells restored the numbers of circulating Ag-specific CD8+ T cells and their intratumoral function, resulting in tumor eradication. These CD4+ T cells had no antitumor effects in the absence of CD8+ T cells and recognized the alloantigen cross-presented on tumor stroma. CD4+ T cells might also be effective in cancer patients when PD1/PD-L1 blockade does not rescue intratumoral CD8+ T-cell function and tumors persist. PMID:28077434

Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB.

PubMed

Jackson-Sillah, Dolly; Cliff, Jacqueline M; Mensah, Gloria Ivy; Dickson, Emmanuel; Sowah, Sandra; Tetteh, John K A; Addo, Kwasi K; Ottenhoff, Tom H M; Bothamley, Graham; Dockrell, Hazel M

2013-01-01

Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are Mycobacterium tuberculosis (Mtb)-specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors. Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC) were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest. The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4(+)FoxP3(+)CD25(hi) cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB. These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes.

Circulating Gut-Homing (α4β7+) Plasmablast Responses against Shigella Surface Protein Antigens among Hospitalized Patients with Diarrhea

PubMed Central

Sinha, Anuradha; Dey, Ayan; Saletti, Giulietta; Samanta, Pradip; Chakraborty, Partha Sarathi; Bhattacharya, M. K.; Ghosh, Santanu; Ramamurthy, T.; Kim, Jae-Ouk; Yang, Jae Seung; Kim, Dong Wook

2016-01-01

Developing countries are burdened with Shigella diarrhea. Understanding mucosal immune responses associated with natural Shigella infection is important to identify potential correlates of protection and, as such, to design effective vaccines. We performed a comparative analysis of circulating mucosal plasmablasts producing specific antibodies against highly conserved invasive plasmid antigens (IpaC, IpaD20, and IpaD120) and two recently identified surface protein antigens, pan-Shigella surface protein antigen 1 (PSSP1) and PSSP2, common to all virulent Shigella strains. We examined blood and stool specimens from 37 diarrheal patients admitted to the Infectious Diseases & Beliaghata General Hospital, Kolkata, India. The etiological agent of diarrhea was investigated in stool specimens by microbiological methods and real-time PCR. Gut-homing (α4β7+) antibody-secreting cells (ASCs) were isolated from patient blood by means of combined magnetic cell sorting and two-color enzyme-linked immunosorbent spot (ELISPOT) assay. Overall, 57% (21 of 37) and 65% (24 of 37) of the patients were positive for Shigella infection by microbiological and real-time PCR assays, respectively. The frequency of α4β7+ IgG ASC responders against Ipas was higher than that observed against PSSP1 or PSSP2, regardless of the Shigella serotype isolated from these patients. Thus, α4β7+ ASC responses to Ipas may be considered an indirect marker of Shigella infection. The apparent weakness of ASC responses to PSSP1 is consistent with the lack of cross-protection induced by natural Shigella infection. The finding that ASC responses to IpaD develop in patients with recent-onset shigellosis indicates that such responses may not be protective or may wane too rapidly and/or be of insufficient magnitude. PMID:27193041

Use of AN Eosinophil Specific Monoclonal Antibody in Assessing Eosinophil Function.

NASA Astrophysics Data System (ADS)

Minkoff, Marjorie Sue

A monoclonal antibody to an eosinophil specific determinant is very important in assessing eosinophil function during helminthic infection. Eosinophils induced by Schistosoma mansoni infection in BALB/c mice were used to induce C57B1/6 immunocytes for production of hybridomas secreting eosinophil monoclonal antibodies. These antibodies were shown to react with an eosinophil surface epitope but not with neutrophils or macrophages as determined by ELISA, immunodiffusion, immunofluorescence, and immunoblot assay. Affinity chromatography with eosinophil chemotactic factor-sepharose consistently selected out a { rm M_ R} 67,000 protein from solubilized eosinophil membrane antigens but not from neutrophil and macrophage antigens. In vitro studies showed that the eosinophil-specific monoclonal antibodies abrogated antibody-dependent eosinophil -mediated killing of S. mansoni schistosomula using mouse, rat or human eosinophils. Neutrophil and macrophage killing activities were unaffected. The monoclonal antibodies effected complement-dependent lysis of mouse and rat eosinophils but not of human eosinophils. ECF-treated eosinophils showed enhanced killing of schistosomula which was blocked by the monoclonal antibody. Murine and human eosinophils preincubated with monoclonal antibody exhibited decreased chemotaxis to ECF at optimal chemotactic concentrations. The monoclonal antibody also blocked eosinophil binding to ECF- sepharose beads. In vivo induction of peripheral blood eosinophilia by injection of S. mansoni eggs was suppressed by injections of monoclonal antibodies 2CD13 and 2QD45 in mouse and rat experimental models. Eosinophilia induced by keyhole limpet hemocyanin- cyclophosphamide treatment was also suppressed by monoclonal antibody in both murine and rat systems. Pulmonary granulomas in mice given egg injection and monoclonal antibody were smaller and contained fewer eosinophils than those granulomas from mice given eggs only. In immuno-biochemical studies, the monoclonal antibody 2QD45 specifically immunoprecipitated the {rm M_ R} 67,000 ECF-binding protein from ^{125}{rm I}-labeled mouse, rat, and human eosinophils as assessed by SDS-PAGE and autoradiography. Two-dimensional gel electrophoresis showed that this ECF-binding protein has a lower PI point than either mouse or bovine albumin.

Schistosome-induced cholangiocyte proliferation and osteopontin secretion correlate with fibrosis and portal hypertension in human and murine schistosomiasis mansoni.

PubMed

Pereira, Thiago A; Syn, Wing-Kin; Machado, Mariana V; Vidigal, Paula V; Resende, Vivian; Voieta, Izabela; Xie, Guanhua; Otoni, Alba; Souza, Márcia M; Santos, Elisângela T; Chan, Isaac S; Trindade, Guilherme V M; Choi, Steve S; Witek, Rafal P; Pereira, Fausto E; Secor, William E; Andrade, Zilton A; Lambertucci, José Roberto; Diehl, Anna Mae

2015-11-01

Schistosomiasis is a major cause of portal hypertension worldwide. It associates with portal fibrosis that develops during chronic infection. The mechanisms by which the pathogen evokes these host responses remain unclear. We evaluated the hypothesis that schistosome eggs release factors that directly stimulate liver cells to produce osteopontin (OPN), a pro-fibrogenic protein that stimulates hepatic stellate cells to become myofibroblasts. We also investigated the utility of OPN as a biomarker of fibrosis and/or severity of portal hypertension. Cultured cholangiocytes, Kupffer cells and hepatic stellate cells were treated with soluble egg antigen (SEA); OPN production was quantified by quantitative reverse transcriptase polymerase chain reaction (qRTPCR) and ELISA; cell proliferation was assessed by BrdU (5-bromo-2'-deoxyuridine). Mice were infected with Schistosoma mansoni for 6 or 16 weeks to cause early or advanced fibrosis. Liver OPN was evaluated by qRTPCR and immunohistochemistry (IHC) and correlated with liver fibrosis and serum OPN. Livers from patients with schistosomiasis mansoni (early fibrosis n=15; advanced fibrosis n=72) or healthy adults (n=22) were immunostained for OPN and fibrosis markers. Results were correlated with plasma OPN levels and splenic vein pressures. SEA-induced cholangiocyte proliferation and OPN secretion (P<0.001 compared with controls). Cholangiocytes were OPN (+) in Schistosoma-infected mice and humans. Liver and serum OPN levels correlated with fibrosis stage (mice: r=0.861; human r=0.672, P=0.0001) and myofibroblast accumulation (mice: r=0.800; human: r=0.761, P=0.0001). Numbers of OPN (+) bile ductules strongly correlated with splenic vein pressure (r=0.778; P=0.001). S. mansoni egg antigens stimulate cholangiocyte proliferation and OPN secretion. OPN levels in liver and blood correlate with fibrosis stage and portal hypertension severity. © 2015 Authors; published by Portland Press Limited.

Effect of heterogeneity of carcinoembryonic antigen on liver cell membrane binding and its kinetics of removal from circulation.

PubMed

Byrn, R A; Medrek, P; Thomas, P; Jeanloz, R W; Zamcheck, N

1985-07-01

Carcinoembryonic antigen (CEA) is a glycoprotein metabolized primarily by the liver. Subcellular fractions of rat liver were examined for CEA binding activity. Hepatocyte plasma membrane and microsome fractions bound CEA, and this binding shared the calcium requirement, neuraminidase sensitivity, and carbohydrate specificity of the hepatocyte asialoglycoprotein receptor. CEA had previously been shown to react with this galactose-specific receptor, in vivo, only following neuraminidase treatment. Galactose receptor binding of CEA was measured in three different purified CEA preparations. The fraction of CEA capable of binding to excess levels of galactose receptor on membranes varied (46.5%, 40.2%, and 4.7% for CEA-1, -2, and -3, respectively). These CEAs were shown to be 2.3%, 7.9%, and 0.7% as effective, respectively, as asialo-alpha 1-acid glycoprotein in inhibiting the binding of radiolabeled asialo-alpha 1-acid glycoprotein to liver cell membranes. Each of the three CEA preparations showed different clearance kinetics from the circulation of mice. Coinjection of asialo-alpha 1-acid glycoprotein with the CEAs revealed differing inhibition of the clearances. These results show that differences in the carbohydrate components of purified CEA preparations affect their rate of removal from circulation and thus possibly the relationship between CEA production and observed plasma levels in patients. The possible origin of these CEA differences is discussed with their clinical implications.

Oligoclonal CD8+ T-cell expansion in patients with chronic hepatitis C is associated with liver pathology and poor response to interferon-alpha therapy.

PubMed

Manfras, Burkhard J; Weidenbach, Hans; Beckh, Karl-Heinz; Kern, Peter; Möller, Peter; Adler, Guido; Mertens, Thomas; Boehm, Bernhard O

2004-05-01

The role of CD8(+) T lymphocytes in chronic hepatitis C virus (HCV) infection and in liver injury with subsequent development of fibrosis and cirrhosis is poorly understood. To address this question, we performed a follow-up study including 27 chronically HCV-infected individuals. We determined clonality and phenotypes of circulating CD8(+) T cells employing TCRBV spectratyping. Antigen specificity was tested by rMHC-peptide tetramer staining and stimulation with recombinant HCV antigens. In addition, T-cell clonality and phenotypes were followed during the variable clinical response of interferon- (IFN) alpha treatment. We could demonstrate that CD8(+) T-cell expansions were significantly associated with liver fibrosis and cirrhosis. Likewise, increased oligoclonality of circulating CD8(+) T cells in chronic HCV infection was identified as an indicator for poor clinical response to IFN-alpha therapy. Moreover, we also found that IFN-alpha therapy enhanced the differentiation of CD8(+) T cells towards a late differentiation phenotype (CD28(-) CD57(+)). In cases of virus elimination the disappearance of expanded terminally differentiated CD8(+) cells was observed. Thus, this study identifies an association of clonal expansions of circulating CD8(+) T cells with liver pathology and provides a possible explanation for the fact that response to IFN-alpha therapy diminishes with the duration of infection.

Improved sensitivity of the urine CAA lateral-flow assay for diagnosing active Schistosoma infections by using larger sample volumes.

PubMed

Corstjens, Paul L A M; Nyakundi, Ruth K; de Dood, Claudia J; Kariuki, Thomas M; Ochola, Elizabeth A; Karanja, Diana M S; Mwinzi, Pauline N M; van Dam, Govert J

2015-04-22

Accurate determination of Schistosoma infection rates in low endemic regions to examine progress towards interruption of transmission and elimination requires highly sensitive diagnostic tools. An existing lateral flow (LF) based test demonstrating ongoing infections through detection of worm circulating anodic antigen (CAA), was improved for sensitivity through implementation of a protocol allowing increased sample input. Urine is the preferred sample as collection is non-invasive and sample volume is generally not a restriction. Centrifugal filtration devices provided a method to concentrate supernatant of urine samples extracted with trichloroacetic acid (TCA). For field trials a practical sample volume of 2 mL urine allowed detection of CAA down to 0.3 pg/mL. The method was evaluated on a set of urine samples (n = 113) from an S. mansoni endemic region (Kisumu, Kenya) and compared to stool microscopy (Kato Katz, KK). In this analysis true positivity was defined as a sample with either a positive KK or UCAA test. Implementation of the concentration method increased clinical sensitivity (Sn) from 44 to 98% when moving from the standard 10 μL (UCAA10 assay) to 2000 μL (UCAA2000 assay) urine sample input. Sn for KK varied between 23 and 35% for a duplicate KK (single stool, two slides) to 52% for a six-fold KK (three consecutive day stools, two slides). The UCAA2000 assay indicated 47 positive samples with CAA concentration above 0.3 pg/mL. The six-fold KK detected 25 egg positives; 1 sample with 2 eggs detected in the 6-fold KK was not identified with the UCAA2000 assay. Larger sample input increased Sn of the UCAA assay to a level indicating 'true' infection. Only a single 2 mL urine sample is needed, but analysing larger sample volumes could still increase test accuracy. The UCAA2000 test is an appropriate candidate for accurate identification of all infected individuals in low-endemic regions. Assay materials do not require refrigeration and collected urine samples may be stored and transported to central test laboratories without the need to be frozen.

Efficacy and Safety of Praziquantel in Preschool-Aged Children in an Area Co-Endemic for Schistosoma mansoni and S. haematobium

PubMed Central

Coulibaly, Jean T.; N'Gbesso, Yve K.; Knopp, Stefanie; Keiser, Jennifer; N'Goran, Eliézer K.; Utzinger, Jürg

2012-01-01

Background In sub-Saharan Africa the recommended strategy to control schistosomiasis is preventive chemotherapy. Emphasis is placed on school-aged children, but in high endemicity areas, preschool-aged children are also at risk, and hence might need treatment with praziquantel. Since a pediatric formulation (e.g., syrup) is not available outside of Egypt, crushed praziquantel tablets are used, but the efficacy and safety of this treatment regimen is insufficiently studied. Methodology We assessed the efficacy and safety of crushed praziquantel tablets among preschool-aged children (<6 years) in the Azaguié district, south Côte d'Ivoire, where Schistosoma mansoni and S. haematobium coexist. Using a cross-sectional design, children provided two stool and two urine samples before and 3 weeks after treatment. Crushed praziquantel tablets, mixed with water, were administered at a dose of 40 mg/kg. Adverse events were assessed and graded 4 and 24 hours posttreatment by interviewing mothers/guardians. Principal Findings Overall, 160 preschool-aged children had at least one stool and one urine sample examined with duplicate Kato-Katz thick smears and a point-of-care circulating cathodic antigen (POC-CCA) cassette for S. mansoni, and urine filtration for S. haematobium diagnosis before and 3 weeks after praziquantel administration. According to the Kato-Katz and urine filtration results, we found high efficacy against S. mansoni (cure rate (CR), 88.6%; egg reduction rate (ERR), 96.7%) and S. haematobium (CR, 88.9%; ERR, 98.0%). POC-CCA revealed considerably lower efficacy against S. mansoni (CR, 53.8%). Treatment was generally well tolerated, but moderately severe adverse events (i.e., body and face inflammation), were observed in four Schistosoma egg-negative children. Conclusions/Significance Crushed praziquantel administered to preschool-aged children at a dose of 40 mg/kg is efficacious against S. mansoni and S. haematobium in a co-endemic setting of Côte d'Ivoire. Further research is required with highly sensitive diagnostic tools and safety must be investigated in more depth. Trial Registration Controlled-Trials.com ISRCTN53172722 PMID:23236526

Structural Basis of Preexisting Immunity to the 2009 H1N1 Pandemic Influenza Virus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xu, Rui; Ekiert, Damian C.; Krause, Jens C.

The 2009 H1N1 swine flu is the first influenza pandemic in decades. The crystal structure of the hemagglutinin from the A/California/04/2009 H1N1 virus shows that its antigenic structure, particularly within the Sa antigenic site, is extremely similar to those of human H1N1 viruses circulating early in the 20th century. The cocrystal structure of the 1918 hemagglutinin with 2D1, an antibody from a survivor of the 1918 Spanish flu that neutralizes both 1918 and 2009 H1N1 viruses, reveals an epitope that is conserved in both pandemic viruses. Thus, antigenic similarity between the 2009 and 1918-like viruses provides an explanation for themore » age-related immunity to the current influenza pandemic.« less

Annual, lunar and diel reproductive periodicity of a spawning aggregation of snapper Pagrus auratus (Sparidae) in a marine embayment on the lower west coast of Australia.

PubMed

Wakefield, C B

2010-10-01

Ichthyoplankton sampling and ovarian characteristics were used to elucidate whether the reproductive cycles of a spawning aggregation of snapper Pagrus auratus in a nearshore marine embayment were temporally and spatially specific and related with environmental conditions. The reproductive dynamics of this aggregation were studied over four consecutive years (2001-2004). Spawning occurred between September and January each year, when water temperatures ranged from 15·8 to 23·1° C. In all 4 years, the cumulative egg densities in Cockburn Sound were highest when water temperatures were between the narrow range of 19-20° C. The spawning fraction of females was monthly bimodal and peaked during new and the full moons at 96-100% and c. 75%, respectively. The backcalculated ages of P. auratus eggs collected from 16 ichthyoplankton surveys demonstrated that P. auratus in Cockburn Sound spawn at night during the 3 h following the high tide. The spatial distributions of P. auratus eggs in Cockburn Sound during the peak reproductive period in all 4 years were consistent, further implying spawning was temporally and spatially specific. High concentrations of recently spawned eggs (8-16 h old) demonstrated spawning also occurred within the adjacent marine embayments of Owen Anchorage and Warnbro Sound. Water circulation in Cockburn and Warnbro Sounds resembled an eddy that was most prominent during the period of highest egg densities, thereby facilitating the retention of eggs in these areas. The reproductive cycles of P. auratus described in this study have assisted managers with the appropriate temporal and spatial scale for a closed fishing season to protect these spawning aggregations. © 2010 The Author. Journal compilation © 2010 The Fisheries Society of the British Isles.

Consequences of elevating plasma testosterone in females of a socially monogamous songbird: evidence of constraints on male evolution?

PubMed

Clotfelter, Ethan D; O'Neal, Dawn M; Gaudioso, Jacqueline M; Casto, Joseph M; Parker-Renga, Ian M; Snajdr, Eric A; Duffy, Deborah L; Nolan, Val; Ketterson, Ellen D

2004-08-01

To explore whether selection for testosterone-mediated traits in males might be constrained by costs of higher testosterone to females, we examined the effects of experimental elevation of plasma testosterone on physiological, reproductive, and behavioral parameters in a female songbird, the dark-eyed junco (Junco hyemalis). We used subcutaneous implants to elevate testosterone (T) in captive and free-living female juncos. In captive birds, we measured the effects of high T on body mass, feather molt, and brood patch formation. In the field, we monitored its effects on the timing of egg laying, clutch size, egg size, egg steroid levels, incubation, and nest-defense behavior. Females implanted with testosterone (T-females) had significantly higher circulating levels of testosterone than did control females (C-females). Captive T-females had lower body mass, were less likely to develop brood patches, and delayed feather molt relative to C-females. Among free-living females, the interval between nest completion and appearance of the first egg was longer for T-females than for C-females and egg yolk concentrations of testosterone were higher, but there were no significant differences in estradiol levels, clutch size, or egg size. Incubation and nest defense behavior were also similar between T- and C-females. Our results suggest that selection on males for higher testosterone might initially lead to a correlated response in females producing changes in body mass and feather molt, both of which could be detrimental. Other possible female responses would be delayed onset of reproduction, which might reduce reproductive success, and higher yolk testosterone, which might have either positive or negative effects on offspring development. We found no reason to expect reduced parental behavior by females as a negative fitness consequence of selection for higher testosterone in males.

Assessment of gastrointestinal parasites in wild chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon

PubMed Central

Bertout, Sébastien; Locatelli, Sabrina; Butel, Christelle; Pion, Sébastien; Mpoudi-Ngole, Eitel; Delaporte, Eric; Peeters, Martine; Mallié, Michèle

2014-01-01

We tested 114 faecal samples from wild simian immunodeficiency virus (SIV)-positive (n=43) and SIV-negative (n=71) chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon for the presence of gastrointestinal parasites by direct smear. We observed cysts from different protozoa (Entamoeba coli and Entamoeba histolytica/Entamoeba dispar, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Balantidium coli and Blastocystis cells) and trophozoites from Troglodytella abrassarti and Balantidium coli. Eggs from different helminths (strongylids, Ascaris lumbricoides, Abbreviata caucasica, Trichuris sp., Capillaria sp., Enterobius anthropopeci, Bertiella sp., Hymenolepis diminuta and an undetermined fluke) were also observed. Finally, we observed eggs that could not be properly identified and classified. We did not observe any differences between the SIV+ and SIV− samples except for the unidentified eggs. The studied chimpanzees were highly parasitised by strongylid (85.1 % of prevalence), Troglodytella (43.8 %) and Blastocystis (2.9 %), and the frequency of the other parasites ranged from 0.9 to 8.8 %. These high levels of parasite infections could represent an additional burden in a population where there is a high rate of the SIV virus in circulation. PMID:24781023

Assessment of gastrointestinal parasites in wild chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon.

PubMed

Drakulovski, Pascal; Bertout, Sébastien; Locatelli, Sabrina; Butel, Christelle; Pion, Sébastien; Mpoudi-Ngole, Eitel; Delaporte, Eric; Peeters, Martine; Mallié, Michèle

2014-07-01

We tested 114 faecal samples from wild simian immunodeficiency virus (SIV)-positive (n = 43) and SIV-negative (n = 71) chimpanzees (Pan troglodytes troglodytes) in southeast Cameroon for the presence of gastrointestinal parasites by direct smear. We observed cysts from different protozoa (Entamoeba coli and Entamoeba histolytica / Entamoeba dispar, Endolimax nana, Iodamoeba butschlii, Chilomastix mesnili, Balantidium coli and Blastocystis cells) and trophozoites from Troglodytella abrassarti and Balantidium coli. Eggs from different helminths (strongylids, Ascaris lumbricoides, Abbreviata caucasica, Trichuris sp., Capillaria sp., Enterobius anthropopeci, Bertiella sp., Hymenolepis diminuta and an undetermined fluke) were also observed. Finally, we observed eggs that could not be properly identified and classified. We did not observe any differences between the SIV+ and SIV- samples except for the unidentified eggs. The studied chimpanzees were highly parasitised by strongylid (85.1% of prevalence), Troglodytella (43.8%) and Blastocystis (2.9%), and the frequency of the other parasites ranged from 0.9 to 8.8%. These high levels of parasite infections could represent an additional burden in a population where there is a high rate of the SIV virus in circulation.

Statistical Physics of Vaccine Design

NASA Astrophysics Data System (ADS)

Deem, Michael

2009-03-01

I will define a new parameter to quantify the antigenic distance between two H3N2 influenza strains. I will use this parameter to measure antigenic distance between circulating H3N2 strains and the closest vaccine component of the influenza vaccine. For the data between 1971 and 2004, the measure of antigenic distance correlates better with efficacy in humans of the H3N2 influenza A annual vaccine than do current state of the art measures of antigenic distance such as phylogenetic sequence analysis or ferret antisera inhibition assays. I suggest that this measure of antigenic distance can be used to guide the design of the annual flu vaccine. I will describe combining this measure of antigenic distance with a multiple-strain avian influenza transmission model to study the threat of simultaneous introduction of multiple avian influenza strains. For H3N2 influenza, the model is validated against observed viral fixation rates and epidemic progression rates from the World Health Organization FluNet - Global Influenza Surveillance Network. I find that a multiple-component avian influenza vaccine is helpful to control a simultaneous multiple introduction of bird-flu strains. I introduce Population at Risk (PaR) to quantify the risk of a flu pandemic, and calculate by this metric the improvement that a multiple vaccine offers.

Maternal derived antibodies induce vaccine-associated enhanced respiratory disease in weaned pigs challenged with heterologous virus

USDA-ARS?s Scientific Manuscript database

Effective vaccine immunization against influenza A viruses (IAV) in pigs in the United States is a challenge because of the great antigenic diversity of co-circulating viruses. Maternally derived antibodies (MDA) interfere with vaccine efficacy and can lead to vaccine-enhanced respiratory disease (V...

Maternal derived antibodies induce vaccine-associated enhanced respiratory disease in weaned pigs challenged with heterologous virus

USDA-ARS?s Scientific Manuscript database

Introduction Effective vaccine immunization against influenza A viruses (IAV) in pigs in the United States is a challenge because of the great antigenic diversity of co-circulating viruses. Another obstacle to vaccine efficacy in pigs is the presence of maternally derived antibodies (MDA), which hav...

Heterologous challenge of weaned piglets in the presence of maternal derived antibodies results in vaccine-associated enhanced respiratory disease

USDA-ARS?s Scientific Manuscript database

Effective vaccine immunization against influenza A viruses (IAV) in pigs in the United States is challenging because of the great antigenic diversity of co-circulating viruses. Maternally derived antibodies (MDA) interfere with vaccine efficacy and can lead to vaccine-enhanced respiratory disease (V...

The genomic and epidemiological dynamics of human influenza A virus.

PubMed

Rambaut, Andrew; Pybus, Oliver G; Nelson, Martha I; Viboud, Cecile; Taubenberger, Jeffery K; Holmes, Edward C

2008-05-29

The evolutionary interaction between influenza A virus and the human immune system, manifest as 'antigenic drift' of the viral haemagglutinin, is one of the best described patterns in molecular evolution. However, little is known about the genome-scale evolutionary dynamics of this pathogen. Similarly, how genomic processes relate to global influenza epidemiology, in which the A/H3N2 and A/H1N1 subtypes co-circulate, is poorly understood. Here through an analysis of 1,302 complete viral genomes sampled from temperate populations in both hemispheres, we show that the genomic evolution of influenza A virus is characterized by a complex interplay between frequent reassortment and periodic selective sweeps. The A/H3N2 and A/H1N1 subtypes exhibit different evolutionary dynamics, with diverse lineages circulating in A/H1N1, indicative of weaker antigenic drift. These results suggest a sink-source model of viral ecology in which new lineages are seeded from a persistent influenza reservoir, which we hypothesize to be located in the tropics, to sink populations in temperate regions.

A serological study of Dirofilaria immitis in feral cats in Grenada, West Indies.

PubMed

Fernandez, C; Chikweto, A; Mofya, S; Lanum, L; Flynn, P; Burnett, J P; Doherty, D; Sharma, R N

2010-12-01

A study to determine the seroprevalence of Dirofilaria immitis was carried out in feral cats in Grenada. Of the 137 feral cats tested for circulating antibodies (IgG; lateral-flow immunoassay) and circulating antigens (Ag; enzyme-linked immunosorbent assay), 8% (95% confidence interval (CI) 3.5-12.5%) were antibody positive and 5.1% (95% CI 1.4-8.8%) were antigen positive. No significant difference between cats aged>1 to 4 years and cats less than 1 year of age was found (P>0.05, χ²). There was also no significant difference (P>0.05, χ²) between male and female cats. Dirofilaria immitis prevalence is relatively high in the feral cat population of Grenada. Evidence of D. immitis infection in feral cats coupled with the endemic nature of heartworm disease in dogs in Grenada leads us to suggest the introduction of heartworm prophylaxis in cats. To the authors' knowledge, this serological evidence of heartworm infection in feral cats in Grenada is the first report from the Caribbean region.

Genetic analysis and antigenic characterization of swine origin influenza viruses isolated from humans in the United States, 1990-2010.

PubMed

Shu, Bo; Garten, Rebecca; Emery, Shannon; Balish, Amanda; Cooper, Lynn; Sessions, Wendy; Deyde, Varough; Smith, Catherine; Berman, LaShondra; Klimov, Alexander; Lindstrom, Stephen; Xu, Xiyan

2012-01-05

Swine influenza viruses (SIV) have been recognized as important pathogens for pigs and occasional human infections with swine origin influenza viruses (SOIV) have been reported. Between 1990 and 2010, a total of twenty seven human cases of SOIV infections have been identified in the United States. Six viruses isolated from 1990 to 1995 were recognized as classical SOIV (cSOIV) A(H1N1). After 1998, twenty-one SOIV recovered from human cases were characterized as triple reassortant (tr_SOIV) inheriting genes from classical swine, avian and human influenza viruses. Of those twenty-one tr_SOIV, thirteen were of A(H1N1), one of A(H1N2), and seven of A(H3N2) subtype. SOIV characterized were antigenically and genetically closely related to the subtypes of influenza viruses circulating in pigs but distinct from contemporary influenza viruses circulating in humans. The diversity of subtypes and genetic lineages in SOIV cases highlights the importance of continued surveillance at the animal-human interface. Copyright © 2011. Published by Elsevier Inc.

Trivalent influenza vaccine-induced antibody response to circulating influenza a (H3N2) viruses in 2010/11 and 2011/12 seasons.

PubMed

Hiroi, Satoshi; Morikawa, Saeko; Nakata, Keiko; Maeda, Akiko; Kanno, Tsuneji; Irie, Shin; Ohfuji, Satoko; Hirota, Yoshio; Kase, Tetsuo

2015-01-01

To evaluate antibody response induced by trivalent inactivated influenza vaccine (TIV) against circulating influenza A (H3N2) strains in healthy adults during the 2010/11 and 2011/12 seasons, a hemagglutination-inhibition (HI) assay was utilized to calculate geometric mean antibody titer (GMT), seroprotection rate (post vaccination HI titers of ≥1 :40), and seroresponse rate (4-fold increase in antibody level). In the 2010/11 season, GMT increased 1.8- to 2.0-fold following the first dose of TIV against 3 circulating strains and 2.2-fold following the second compared to before vaccination. The seroresponse rate ranged from 22% to 26% following the first dose of TIV and from 31% to 33% following the second (n = 54 ). The seroprotection rate increased from a range of 6% to 13% to a range of 26% to 33% following the first dose of TIV and to a range of 37% to 42% following the second (n = 54 ). In the 2011/12 season, GMT increased 1.4-fold against A/Osaka/110/2011 and 1.8-fold against A/Osaka/5/2012. For A/Osaka/110/2011, the seroresponse rate was 29%, and the seroprotection rate increased from 26% to 55% following vaccination (n = 31 ). For A/Osaka/5/2012, the seroresponse rate was 26%, and the seroprotection rate increased from 68% to 84% following vaccination (n = 31 ). HI assays with reference antisera demonstrated that the strains in the 2011/12 season were antigenically distinct from vaccine strain (A/Victoria/210/2009). In conclusion, the vaccination increased the seroprotection rate against circulating H3N2 strains in the 2010/11 and 2011/12 seasons. Vaccination of TIV might have potential to induce reactive antibodies against antigenically distinct circulating H3N2 viruses.

First molecular characterization of canine parvovirus strains in Sardinia, Italy.

PubMed

Dei Giudici, S; Cubeddu, T; Giagu, A; Sanna, G; Rocca, S; Oggiano, A

2017-11-01

Canine parvovirus type 2 (CPV-2) is responsible of acute hemorrhagic gastroenteritis in young dogs. CPV-2 emerged in 1978 in the USA, but new antigenic types, CPV-2a, 2b and 2c, have completely replaced the original type. In this study, we analyzed 81 animals collected in Sardinia, Italy. The VP2 sequence analysis of 27 positive samples showed that all antigenic CPV-2 types are circulating. CPV-2b seems to be the most widespread variant, followed by CPV-2a. Furthermore, 12 CPV-2b strains displayed further amino acid substitutions and formed a separate cluster in a phylogenetic tree, indicating regional genetic variation.

Comprehensive Analysis and Characterization of Linear Antigenic Domains on HN Protein from Genotype VII Newcastle Disease Virus Using Yeast Surface Display System

PubMed Central

Li, Tao; Wang, Gaoling; Shi, Bingtian; Liu, Peixin; Si, Wei; Wang, Bin; Jiang, Li; Zhou, Lunjiang; Xiu, Jinsheng; Liu, Henggui

2015-01-01

Circulation of genotype VII Newcastle disease virus (NDV) has posed a great threat for the poultry industry worldwide. Antibodies against Hemagglutinin-neuraminidase (HN), a membrane protein of NDV with critical roles in NDV infection, have been reported to provide chickens protection from NDV infection. In this study, we comprehensively analyzed the in vivo antibody responses against the linear antigenic domains of the HN protein from genotype VII NDV using a yeast surface display system. The results revealed four distinct regions of HN, P1 (1-52aa), P2 (53-192aa), P3 (193-302aa) and P4 (303-571aa), respectively, according to their antigenic potency. Analysis by FACS and ELISA assay indicated P2 to be the dominant linear antigenic domain, with the immunogenic potency to protect the majority of chickens from NDV challenge. In contrast, the P1, P3 and P4 domains showed weak antigenicity in vivo and could not protect chickens from NDV challenge. These results provide important insight into the characteristic of humoral immune responses elicited by HN of NDV in vivo. PMID:26121247

A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines

PubMed Central

Laws, Thomas R.; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F.; Webster, Wendy M.; Debes, Amanda K.; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G.; Tsanava, Shota; Dyson, Edward H.; Simpson, Andrew J. H.; Hepburn, Matthew J.; Trapaidze, Nino

2016-01-01

Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens. PMID:27007118

Site-specific incorporation of three toll-like receptor 2 targeting adjuvants into semisynthetic, molecularly defined nanoparticles: application to group a streptococcal vaccines.

PubMed

Moyle, Peter M; Dai, Wei; Zhang, Yingkai; Batzloff, Michael R; Good, Michael F; Toth, Istvan

2014-05-21

Subunit vaccines offer a means to produce safer, more defined vaccines compared to traditional whole microorganism approaches. Subunit antigens, however, exhibit weak immunity, which is normally overcome through coadministration with adjuvants. Enhanced vaccine properties (e.g., improved potency) can be obtained by linking antigen and adjuvant, as observed for synthetic peptide antigens and Toll-like receptor 2 (TLR2) ligands. As few protective peptide antigens have been reported, compared to protein antigens, we sought to extend the utility of this approach to recombinant proteins, while ensuring that conjugation reactions yielded a single, molecularly defined product. Herein we describe the development and optimization of techniques that enable the efficient, site-specific attachment of three synthetic TLR2 ligands (lipid core peptide (LCP), Pam2Cys, and Pam3Cys) onto engineered protein antigens, permitting the selection of optimal TLR2 agonists during the vaccine development process. Using this approach, broadly protective (J14) and population targeted (seven M protein N-terminal antigens) multiantigenic vaccines against group A streptococcus (GAS; Streptococcus pyogenes) were produced and observed to self-assemble in PBS to yield nanoparticules (69, 101, and 123 nm, respectively). All nanoparticle formulations exhibited self-adjuvanting properties, with rapid, persistent, antigen-specific IgG antibody responses elicited toward each antigen in subcutaneously immunized C57BL/6J mice. These antibodies were demonstrated to strongly bind to the cell surface of five GAS serotypes that are not represented by vaccine M protein N-terminal antigens, are among the top 20 circulating strains in developed countries, and are associated with clinical disease, suggesting that these vaccines may elicit broadly protective immune responses.

Intakes of meat, fish, poultry, and eggs and risk of prostate cancer progression.

PubMed

Richman, Erin L; Stampfer, Meir J; Paciorek, Alan; Broering, Jeanette M; Carroll, Peter R; Chan, June M

2010-03-01

Processed meat and fish have been shown to be associated with the risk of advanced prostate cancer, but few studies have examined diet after prostate cancer diagnosis and risk of its progression. We examined the association between postdiagnostic consumption of processed and unprocessed red meat, fish, poultry, and eggs and the risk of prostate cancer recurrence or progression. We conducted a prospective study in 1294 men with prostate cancer, without recurrence or progression as of 2004-2005, who were participating in the Cancer of the Prostate Strategic Urologic Research Endeavor and who were followed for an average of 2 y. We observed 127 events (prostate cancer death or metastases, elevated prostate-specific antigen concentration, or secondary treatment) during 2610 person-years. Intakes of processed and unprocessed red meat, fish, total poultry, and skinless poultry were not associated with prostate cancer recurrence or progression. Greater consumption of eggs and poultry with skin was associated with 2-fold increases in risk in a comparison of extreme quantiles: eggs [hazard ratio (HR): 2.02; 95% CI: 1.10, 3.72; P for trend = 0.05] and poultry with skin (HR: 2.26; 95% CI: 1.36, 3.76; P for trend = 0.003). An interaction was observed between prognostic risk at diagnosis and poultry. Men with high prognostic risk and a high poultry intake had a 4-fold increased risk of recurrence or progression compared with men with low/intermediate prognostic risk and a low poultry intake (P for interaction = 0.003). Our results suggest that the postdiagnostic consumption of processed or unprocessed red meat, fish, or skinless poultry is not associated with prostate cancer recurrence or progression, whereas consumption of eggs and poultry with skin may increase the risk.

Intakes of meat, fish, poultry, and eggs and risk of prostate cancer progression1234

PubMed Central

Richman, Erin L; Stampfer, Meir J; Paciorek, Alan; Broering, Jeanette M; Carroll, Peter R; Chan, June M

2010-01-01

Background: Processed meat and fish have been shown to be associated with the risk of advanced prostate cancer, but few studies have examined diet after prostate cancer diagnosis and risk of its progression. Objective: We examined the association between postdiagnostic consumption of processed and unprocessed red meat, fish, poultry, and eggs and the risk of prostate cancer recurrence or progression. Design: We conducted a prospective study in 1294 men with prostate cancer, without recurrence or progression as of 2004–2005, who were participating in the Cancer of the Prostate Strategic Urologic Research Endeavor and who were followed for an average of 2 y. Results: We observed 127 events (prostate cancer death or metastases, elevated prostate-specific antigen concentration, or secondary treatment) during 2610 person-years. Intakes of processed and unprocessed red meat, fish, total poultry, and skinless poultry were not associated with prostate cancer recurrence or progression. Greater consumption of eggs and poultry with skin was associated with 2-fold increases in risk in a comparison of extreme quantiles: eggs [hazard ratio (HR): 2.02; 95% CI: 1.10, 3.72; P for trend = 0.05] and poultry with skin (HR: 2.26; 95% CI: 1.36, 3.76; P for trend = 0.003). An interaction was observed between prognostic risk at diagnosis and poultry. Men with high prognostic risk and a high poultry intake had a 4-fold increased risk of recurrence or progression compared with men with low/intermediate prognostic risk and a low poultry intake (P for interaction = 0.003). Conclusions: Our results suggest that the postdiagnostic consumption of processed or unprocessed red meat, fish, or skinless poultry is not associated with prostate cancer recurrence or progression, whereas consumption of eggs and poultry with skin may increase the risk. PMID:20042525

Mumps outbreaks in a highly vaccinated population: Investigation of a neutralization titre against the current circulating wildtype genotype G5 mumps virus.

PubMed

Kenny, Lena; O'Kelly, Edwin; Connell, Jeff; De Gascun, Cillian; Hassan, Jaythoon

2016-01-01

Mumps outbreaks continue to occur globally, despite high levels of uptake of the mumps vaccine. In order to address immunity to the current circulating wildtype virus, we sought to determine a mumps G5 specific IgG quantitative value which correlates with genotype G5 specific neutralization ability in vitro. Sera from 199 individuals including controls and acute mumps cases were assessed for mumps specific IgG titres using five different enzyme immunoassays coated with antigen from different mumps virus strains. A subset of 66 sera was also assessed for in vitro neutralizing antibody against a contemporary circulating genotype G5 mumps virus. For all the different antigenic targets, mumps specific IgG titres were higher in patients following acute mumps infection compared to controls. In acute mumps infected patients, females showed significantly higher serum titres of anti-G5 IgG compared to males (p<0.05). Furthermore, control males did not show any change in G5 specific IgG with increasing age whereas females show a progressive rise in titre. Linear regression analysis revealed a significant association between the mumps G5 specific IgG levels in the EIA and the in vitro neutralization titres (r(2)=0.59). Specific IgG to the current circulating genotype G5 mumps strain showed significantly lower titres in males which supports our previous observation that there is a male gender bias in cases of acute mumps infection. Furthermore, in this preliminary study, the data indicate that genotype G5 specific IgG levels of >40 RU/ml are required for neutralization capability to be observed in vitro. Copyright © 2015 Elsevier B.V. All rights reserved.

B-cell polyclonal activation and Epstein-Barr viral abortive lytic cycle are two key features in acute infectious mononucleosis.

PubMed

Al Tabaa, Yassine; Tuaillon, Edouard; Jeziorski, Eric; Ouedraogo, David Eric; Bolloré, Karine; Rubbo, Pierre-Alain; Foulongne, Vincent; Rodière, Michel; Vendrell, Jean-Pierre

2011-09-01

Acute infectious mononucleosis (AIM) is generally associated with a large EBV B cell reservoir cells and an intense B-cell polyclonal activation whereas the number of quiescent EBV-infected memory B cells in chronically EBV-infected healthy controls is very low. To evaluate the extent and functionality of ex vivo B-cell polyclonal activation, quantify the EBV DNA integrated in B cells, enumerate the functional EBV DNA reservoir in B cells and circulating B cells spontaneously secreting EBV antigens in AIM. Circulating B cells and B cells differentiating into plamablasts and plasma cells, early (BZLF1)- and late viral antigen (gp350)-secreting-cells (SCs) were enumerated in six AIM patients and seven healthy EBV carriers. In vitro B-cell polyclonal activation induced 8000-24,000 BZLF1- and 1000-3000gp350-SCs/10(6) B cells, respectively. These data suggest that only 11.1-19.5% of cells expressing BZLF1 synthesized gp350 and so completed the EBV-lytic cycle. Furthermore, circulating spontaneous BZLF1- and gp350-SCs that reflect ongoing viral replication were rare (20-120 and 10-30/10(6) B cells, respectively), and their low numbers contrasted with the high levels of circulating plasma cells (1.1-10.2% of CD19(+) B cells). The in vivo terminal-B-cell differentiation into plasma cells could unmask EBV B-cell reservoir to specific cytotoxic T-cell response and combined with a predominant abortive functional-EBV-reservoir, strongly contribute to rapid decay of cellular EBV reservoir in AIM. Copyright © 2011 Elsevier B.V. All rights reserved.

Longitudinal analysis of antigen specific response in individuals with Schistosoma mansoni infection in an endemic area of Minas Gerais, Brazil

PubMed Central

Matoso, Leonardo Ferreira; Oliveira-Prado, Roberta; Abreu, Mery Natali Silva; Fujiwara, Ricardo Toshio; LoVerde, Philip T.; Kloos, Helmut; Gazzinelli, Andréa; Correa-Oliveira, Rodrigo

2013-01-01

Background Immunoepidemiologic studies have shown a relationship between IgE and IgG4 antibodies with age and with resistance and susceptibility to infection. It is believed that the IgE and IgG4 responses to soluble egg antigen (SEA) can be used for serological analysis of infection and post-treatment status. This study aimed to evaluate the association between Schistosoma mansoni infection and anti-SEA IgG4 and IgE reactivities, and determine whether these reactivities could be used as biomarkers of infection. Methods Between 2001 and 2009, a longitudinal study was performed in which parasitologic and blood specimens and socioeconomic and water-contact information were collected from 127 individuals. All patients positive for S. mansoni infection were treated. Results Schistosomiasis prevalence and the geometric mean of the egg count in 2001 were 59% and 61.05, respectively, decreasing to 26.8% and 8.78 in 2009. IgG4 anti-SEA reactivity in infected individuals was significantly higher than that in uninfected individuals at all time points. Analysis of receiver-operating characteristic (ROC) area showed that the IgG4 anti-SEA antibodies were able to predict infection by S. mansoni at each time point. Conclusion IgG4 anti-SEA reactivity can be used as a biomarker for immune monitoring of the presence of infection with S. mansoni in endemic areas. PMID:24189480

A harmonized immunoassay with liquid chromatography-mass spectrometry analysis in egg allergen determination.

PubMed

Nimata, Masaomi; Okada, Hideki; Kurihara, Kei; Sugimoto, Tsukasa; Honjoh, Tsutomu; Kuroda, Kazuhiko; Yano, Takeo; Tachibana, Hirofumi; Shoji, Masahiro

2018-01-01

Food allergy is a serious health issue worldwide. Implementing allergen labeling regulations is extremely challenging for regulators, food manufacturers, and analytical kit manufacturers. Here we have developed an "amino acid sequence immunoassay" approach to ELISA. The new ELISA comprises of a monoclonal antibody generated via an analyte specific peptide antigen and sodium lauryl sulfate/sulfite solution. This combination enables the antibody to access the epitope site in unfolded analyte protein. The newly developed ELISA recovered 87.1%-106.4% ovalbumin from ovalbumin-incurred model processed foods, thereby demonstrating its applicability as practical egg allergen determination. Furthermore, the comparison of LC-MS/MS and the new ELISA, which targets the amino acid sequence conforming to the LC-MS/MS detection peptide, showed a good agreement. Consequently the harmonization of two methods was demonstrated. The complementary use of the new ELISA and LC-MS analysis can offer a wide range of practical benefits in terms of easiness, cost, accuracy, and efficiency in food allergen analysis. In addition, the new assay is attractive in respect to its easy antigen preparation and predetermined specificity. Graphical abstract The ELISA composing of the monoclonal antibody targeting the amino acid sequence conformed to LC-MS detection peptide, and the protein conformation unfolding reagent was developed. In ovalbumin determination, the developed ELISA showed a good agreement with LC-MS analysis. Consequently the harmonization of immunoassay with LC-MS analysis by using common target amino acid sequence was demonstrated.

Egg, red meat, and poultry intake and risk of lethal prostate cancer in the prostate specific antigen-era: incidence and survival

PubMed Central

Richman, Erin L.; Kenfield, Stacey A.; Stampfer, Meir J.; Giovannucci, Edward L.; Chan, June M.

2011-01-01

Red and processed meat may increase risk of advanced prostate cancer. Data on post-diagnostic diet and prostate cancer are sparse, but post-diagnostic intake of poultry with skin and eggs may increase risk of disease progression. Therefore, we prospectively examined total, unprocessed, and processed red meat, poultry, and eggs in relation to risk of lethal prostate cancer (e.g. men without cancer at baseline who developed distant organ metastases or died from prostate cancer during follow-up) among 27, 607 men followed from 1994–2008. We also performed a case-only survival analysis to examine post-diagnostic consumption of these foods and risk of lethal prostate cancer among the 3,127 men initially diagnosed with non-metastatic prostate cancer during follow-up. In the incidence analysis, we observed 199 events during 306,715 person-years. Men who consumed 2.5 or more eggs per week had an 81% increased risk of lethal prostate cancer compared to men who consumed less than 0.5 eggs per week (HR: 1.81; 95% confidence interval (CI): 1.13, 2.89; p-trend: 0.01). In the case-only survival analysis, we observed 123 events during 19,354 person-years. There were suggestive, but not statistically significant, positive associations between post-diagnostic poultry (HR ≥3.5 vs. <1.5 servings per week: 1.69; 95%CI: 0.96, 2.99; p-trend: 0.07) and post-diagnostic processed red meat (HR ≥3 vs. <0.5 servings per week: 1.45; 95%CI: 0.73, 2.87; p-trend: 0.08) and risk of progression of localized prostate cancer to lethal disease. In conclusion, consumption of eggs may increase risk of developing a lethal-form of prostate cancer among healthy men. PMID:21930800

Usefulness of antigen-specific IgE probability curves derived from the 3gAllergy assay in diagnosing egg, cow's milk, and wheat allergies.

PubMed

Sato, Sakura; Ogura, Kiyotake; Takahashi, Kyohei; Sato, Yasunori; Yanagida, Noriyuki; Ebisawa, Motohiro

2017-04-01

Specific IgE (sIgE) antibody detection using the Siemens IMMULITE ® 3gAllergy™ (3gAllergy) assay have not been sufficiently examined for the diagnosis of food allergy. The aim of this study was to evaluate the utility of measuring sIgE levels using the 3gAllergy assay to diagnose allergic reactions to egg, milk, and wheat. This retrospective study was conducted on patients with diagnosed or suspected allergies to egg, milk and wheat. Patients were divided into two groups according to their clinical reactivity to these allergens based on oral food challenge outcomes and/or convincing histories of immediate reaction to causative food(s). The sIgE levels were measured using 3gAllergy and ImmunoCAP. Predicted probability curves were estimated using logistic regression analysis. We analyzed 1561 patients, ages 0-19 y (egg = 436, milk = 499, wheat = 626). The sIgE levels determined using 3gAllergy correlated with those of ImmunoCAP, classifying 355 patients as symptomatic: egg = 149, milk = 123, wheat = 83. 3gAllergy sIgE levels were significantly higher in symptomatic than in asymptomatic patients (P < 0.0001). Predictive probability for positive food allergy was significantly increased and correlated with increased sIgE levels. The cut-offs for allergic reaction with 95% predictive probability as determined by the 3gAllergy probability curves were different from those of ImmunoCAP. Measurements of sIgE against egg, milk, and wheat as determined by 3gAllergy may be used as a tool to facilitate the diagnosis of food allergy in subjects with suspected food allergies. However, these probability curves should not be applied interchangeably between different assays. Copyright © 2016 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Assessing the validity of an ELISA test for the serological diagnosis of human fascioliasis in different epidemiological situations.

PubMed

Valero, M Adela; Periago, M Victoria; Pérez-Crespo, Ignacio; Rodríguez, Esperanza; Perteguer, M Jesús; Gárate, Teresa; González-Barberá, Eva M; Mas-Coma, Santiago

2012-05-01

To improve the diagnosis of human fascioliasis caused by Fasciola hepatica and Fasciola gigantica, we evaluated the diagnostic accuracy of an enzyme-linked immunosorbent assay (ELISA), with Fasciola antigen from the adult liver fluke, for the detection of IgG against fascioliasis in human sera. The sera of 54 fascioliasis cases, originating from three endemic areas, were used in this evaluation: (i) a hyperendemic F. hepatica area where humans usually shed a great number of parasite eggs in faeces (11 sera); (ii) an epidemic F. hepatica area where humans usually shed small amounts of parasite eggs (24 sera) and (iii) an overlap area of both Fasciola species and where human shedding of parasite eggs in faeces is usually scarce or non-existent (19 sera). One hundred and sixty-eight patients with other parasitic infections and 89 healthy controls were also analysed. The respective sensitivity and specificity of this assay were 95.3% (95% confidence intervals, 82.9-99.2%) and 95.7% (95% confidence intervals, 92.3-97.5%). No correlation between egg output and the OD450 values of the F. hepatica IgG ELISA test was observed. This test could be used both as an individual serodiagnostic test for human fascioliasis when backed up by a compatible clinical history together with a second diagnostic technique for other cross-reactive helminth infections, and in large-scale epidemiological studies of human fascioliasis worldwide. © 2012 Blackwell Publishing Ltd.

Anti-IL-5 attenuates activation and surface density of β(2) -integrins on circulating eosinophils after segmental antigen challenge.

PubMed

Johansson, M W; Gunderson, K A; Kelly, E A B; Denlinger, L C; Jarjour, N N; Mosher, D F

2013-03-01

IL-5 activates α(M) β(2) integrin on blood eosinophils in vitro. Eosinophils in bronchoalveolar lavage (BAL) following segmental antigen challenge have activated β(2) -integrins. To identify roles for IL-5 in regulating human eosinophil integrins in vivo. Blood and BAL eosinophils were analysed by flow cytometry in ten subjects with allergic asthma who underwent a segmental antigen challenge protocol before and after anti-IL-5 administration. Blood eosinophil reactivity with monoclonal antibody (mAb) KIM-127, which recognizes partially activated β(2) -integrins, was decreased after anti-IL-5. Before anti-IL-5, surface densities of blood eosinophil β(2) , α(M) and α(L) integrin subunits increased modestly post challenge. After anti-IL-5, such increases did not occur. Before or after anti-IL-5, surface densities of β(2) , α(M) , α(L) and α(D) and reactivity with KIM-127 and mAb CBRM1/5, which recognizes high-activity α(M) β(2) , were similarly high on BAL eosinophils 48 h post-challenge. Density and activation state of β(1) -integrins on blood and BAL eosinophils were not impacted by anti-IL-5, even though anti-IL-5 ablated a modest post-challenge increase on blood or BAL eosinophils of P-selectin glycoprotein ligand-1 (PSGL-1), a receptor for P-selectin that causes activation of β(1) -integrins. Forward scatter of blood eosinophils post-challenge was less heterogeneous and on the average decreased after anti-IL-5; however, anti-IL-5 had no effect on the decreased forward scatter of eosinophils in post-challenge BAL compared with eosinophils in blood. Blood eosinophil KIM-127 reactivity at the time of challenge correlated with the percentage of eosinophils in BAL post-challenge. IL-5 supports a heterogeneous population of circulating eosinophils with partially activated β(2) -integrins and is responsible for up-regulation of β(2) -integrins and PSGL-1 on circulating eosinophils following segmental antigen challenge but has minimal effects on properties of eosinophils in BAL. Dampening of β(2) -integrin function of eosinophils in transit to inflamed airway may contribute to the decrease in lung inflammation caused by anti-IL-5. © 2012 Blackwell Publishing Ltd.

Anti-IL-5 attenuates activation and surface density of β2-integrins on circulating eosinophils after segmental antigen challenge

PubMed Central

Johansson, Mats W.; Gunderson, Kristin A.; Kelly, Elizabeth A. B.; Denlinger, Loren C.; Jarjour, Nizar N.; Mosher, Deane F.

2013-01-01

Background IL-5 activates αMβ2 integrin on blood eosinophils in vitro. Eosinophils in bronchoalveolar lavage (BAL) following segmental antigen challenge have activated β2-integrins. Objective To identify roles for IL-5 in regulating human eosinophil integrins in vivo. Methods Blood and BAL eosinophils were analyzed by flow cytometry in ten subjects with allergic asthma who underwent a segmental antigen challenge protocol before and after anti-IL-5 administration. Results Blood eosinophil reactivity with monoclonal antibody (mAb) KIM-127, which recognizes partially activated β2-integrins, was decreased after anti-IL-5. Before anti-IL-5, surface densities of blood eosinophil β2, αM, and αL integrin subunits increased modestly post-challenge. After anti-IL-5, such increases did not occur. Before or after anti-IL-5, surface densities of β2,αM, αL, and αD and reactivity with KIM-127 and mAb CBRM1/5, which recognizes high-activity αMβ2, were similarly high on BAL eosinophils 48 h post-challenge. Density and activation state of β1-integrins on blood and BAL eosinophils were not impacted by anti-IL-5, even though anti-IL-5 ablated a modest post-challenge increase on blood or BAL eosinophils of P-selectin glycoprotein ligand-1 (PSGL-1), a receptor for P-selectin that causes activation of β1-integrins. Forward scatter of blood eosinophils post-challenge was less heterogeneous and on the average decreased after anti-IL-5; however, anti-IL-5 had no effect on the decreased forward scatter of eosinophils in post-challenge BAL compared to eosinophils in blood. Blood eosinophil KIM-127 reactivity at the time of challenge correlated with the percentage of eosinophils in BAL post-challenge. Conclusion and Clinical Relevance IL-5 supports a heterogeneous population of circulating eosinophils with partially activated β2-integrins and is responsible for upregulation of β2-integrins and PSGL-1 on circulating eosinophils following segmental antigen challenge but has minimal effects on properties of eosinophils in BAL. Dampening of β2-integrin function of eosinophils in transit to inflamed airway may contribute to the decrease in lung inflammation caused by anti-IL-5. PMID:23414537

Serologic screenings for H7N9 from three sources among high-risk groups in the early stage of H7N9 circulation in Guangdong Province, China.

PubMed

Wu, Jie; Zou, Lirong; Ni, Hanzhong; Pei, Lei; Zeng, Xianqiao; Liang, Lijun; Zhong, Haojie; He, Jianfeng; Song, Yingchao; Kang, Min; Zhang, Xin; Lin, Jinyan; Ke, Changwen

2014-10-23

The aim of this study was to assess the prevalence of the novel avian influenza A virus (H7N9) in three high risk groups. The groups were divided into those exposed through infected individuals, those exposed through poultry and those individuals exposed through the external environment, in the early stage of the epidemic in Guangdong Province, which is located in the southern region of China. Serologic studies were conducted among samples collected from individuals who had close contact with the first H7N9 infected patient reported in Guangdong Province, those who were most likely exposed to the first group of H7N9 infected poultry, and those who might have been exposed to H7N9 in the environmental settings, namely hemagglutinin inhibition (HI) and microneutralizaiton(MN) assays using three viruses as antigens. The alignment results of the viral sequences indicated the similarity of the HA gene sequence among viruses from exposure to infected poultry, infected humans and contaminated environments were highly conserved. Seven samples of individuals exposed to contaminated environments were positive in the HI assay and one sample among them was positive in the MN assay using poultry H7N9 virus as the antigen. One sample was positive against human H7N9 virus and 3 samples were positive against environmental H7N9 among those that were in contact with infected patients in HI assay. None of these were positive in MN assay. All HI titers of the 240 samples from those individuals in contact with infected poultry were less than 40 aganist the antigens from three viruses. The results suggest that when the H7N9 virus was in the early stages of circulation in Guangdong Province, the antigenic sites of the HA proteins of the H7N9 strain isolated from different hosts were highly conserved. The risk of new infection is low in individuals who have contact with the infected patients, poultry or a contaminated environment in the early stages of the circulation of the H7N9 virus.

Microfluidic devices for the isolation of circulating rare cells: a focus on affinity-based, dielectrophoresis, and hydrophoresis.

PubMed

Hyun, Kyung-A; Jung, Hyo-Il

2013-04-01

Circulating rare cells have attracted interest because they can be good indicators of various types of diseases. For example, enumeration of circulating tumor cells is used for cancer diagnosis and prognosis, while DNA analysis or enumeration of nucleated red blood cells is useful for prenatal diagnosis or hypoxic anemia, and that of circulating stem cells to diagnose cancer metastasis. Isolation of these cells and their downstream analyses can provide significant information such as the origin and characteristics of a disease. Novel approaches based on microfluidics have many advantages, including the continuous process and integration with other components for analysis. For these reasons, a variety of microfluidic devices have been developed to isolate and characterize rare cells. In this article, we review several microfluidic devices, with a focus on affinity-based isolation (e.g. antigen-antibody reaction) and label-free separation (DEP and hydrophoresis). © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Human respiratory syncytial virus genomic and antigenic variants isolated in two hospitals during one epidemic, in Santiago, Chile.

PubMed

Luchsinger, Vivian; Noy, Andrea Elgueta; Avendaño, Luis F

2008-07-01

Human respiratory syncytial virus (HRSV) is a major cause of severe lower respiratory tract infection (LRI) in children. Distinct variants of the viruses have been described. The objective was to compare the antigenic and genetic variability of HRSV strains recovered from infants admitted to two hospitals during one epidemic in a big city. We analyzed nasopharyngeal aspirates from 201 infants admitted for LRI to two hospitals during 2002 in Santiago, Chile. The analyses were carried out using a panel of monoclonal antibodies against G glycoprotein epitopes (EIA) and RFLP for N and G genes. No differences in HRSV groups A/B and in N patterns distribution were observed among both hospitals. On the contrary, antigenic and genetic G patterns displayed a wide diversity of strains circulating during one epidemic, in one big city. RSV variability assessment depended rather on the tool used for analysis than on the geographical location.

Dynamics of T cell, antigen-presenting cell, and pathogen interactions during recall responses in the lymph node.

PubMed

Chtanova, Tatyana; Han, Seong-Ji; Schaeffer, Marie; van Dooren, Giel G; Herzmark, Paul; Striepen, Boris; Robey, Ellen A

2009-08-21

Memory T cells circulate through lymph nodes where they are poised to respond rapidly upon re-exposure to a pathogen; however, the dynamics of memory T cell, antigen-presenting cell, and pathogen interactions during recall responses are largely unknown. We used a mouse model of infection with the intracellular protozoan parasite, Toxoplasma gondii, in conjunction with two-photon microscopy, to address this question. After challenge, memory T cells migrated more rapidly than naive T cells, relocalized toward the subcapsular sinus (SCS) near invaded macrophages, and engaged in prolonged interactions with infected cells. Parasite invasion of T cells occurred by direct transfer of the parasite from the target cell into the T cell and corresponded to an antigen-specific increase in the rate of T cell invasion. Our results provide insight into cellular interactions during recall responses and suggest a mechanism of pathogen subversion of the immune response.

Elevated and cross‐responsive CD1a‐reactive T cells in bee and wasp venom allergic individuals

PubMed Central

Subramaniam, Sumithra; Aslam, Aamir; Misbah, Siraj A.; Salio, Mariolina; Cerundolo, Vincenzo; Moody, D Branch

2015-01-01

The role of CD1a‐reactive T cells in human allergic disease is unknown. We have previously shown that circulating CD1a‐reactive T cells recognize neolipid antigens generated by bee and wasp venom phospholipase, and here tested the hypothesis that venom‐responsive CD1a‐reactive T cells associate with venom allergy. Circulating T cells from bee and wasp venom allergic individuals, before and during immunotherapy, were exposed to CD1a‐transfected K562 cells in the presence of wasp or bee venom. T‐cell response was evaluated based on IFNγ, GM‐CSF, and IL‐13 cytokine production. Venom allergic individuals showed significantly higher frequencies of IFN‐γ, GM‐CSF, and IL‐13 producing CD1a‐reactive T cells responsive to venom and venom‐derived phospholipase than healthy individuals. Venom‐responsive CD1a‐reactive T cells were cross‐responsive between wasp and bee suggesting shared pathways of allergenicity. Frequencies of CD1a‐reactive T cells were initially induced during subcutaneous immunotherapy, peaking by weeks 5, but then reduced despite escalation of antigen dose. Our current understanding of venom allergy and immunotherapy is largely based on peptide and protein‐specific T cell and antibody responses. Here, we show that lipid antigens and CD1a‐reactive T cells associate with the allergic response. These data have implications for mechanisms of allergy and approaches to immunotherapy. PMID:26518614

Reduced Memory CD4+ T-Cell Generation in the Circulation of Young Children May Contribute to the Otitis-Prone Condition

PubMed Central

Sharma, Sharad K.; Casey, Janet R.

2011-01-01

Background. An explanation for the immunologic dysfunction that causes children to be prone to repeated episodes of acute otitis media (AOM) has long been sought. Poor antibody response has been associated with the otitis-prone condition; however, there is no precise mechanistic explanation for this condition. Methods. Non–otitis-prone and otitis-prone children with AOM or nasopharyngeal (NP) colonization caused by either Streptococcus pneumoniae or Haemophilus influenzae were compared for pathogen-specific CD4+ T-helper memory responses by stimulating peripheral blood mononuclear cells using 6 vaccine candidate S. pneumoniae and 3 H. influenzae protein antigens. Samples were analyzed by multi-parameter flow cytometry. Results. Significantly reduced percentages of functional CD45RALow memory CD4+ T cells producing specific cytokines (interferon γ, interleukin [IL]–2, IL-4 and IL-17a) were observed in otitis-prone children following AOM and NP colonization with either S. pneumoniae or H. influenzae. Immunoglobulin (Ig) G responses to the studied protein antigens were reduced, which suggests that antigen-specific B-cell function may be compromised as a result of poor T-cell help. Staphylococcal enterotoxin B stimulated similar cytokine patterns in memory CD4+T cells in both groups of children. Conclusions. Otitis-prone children have suboptimal circulating functional T-helper memory and reduced IgG responses to S. pneumoniae or H. influenzae after colonization and after AOM; this immune dysfunction causes susceptibility to recurrent AOM infections. PMID:21791667

TLR-adjuvanted nanoparticle vaccines differentially influence the quality and longevity of responses to malaria antigen Pfs25.

PubMed

Thompson, Elizabeth A; Ols, Sebastian; Miura, Kazutoyo; Rausch, Kelly; Narum, David L; Spångberg, Mats; Juraska, Michal; Wille-Reece, Ulrike; Weiner, Amy; Howard, Randall F; Long, Carole A; Duffy, Patrick E; Johnston, Lloyd; O'Neil, Conlin P; Loré, Karin

2018-05-17

Transmission-blocking vaccines (TBVs) are considered an integral element of malaria eradication efforts. Despite promising evaluations of Plasmodium falciparum Pfs25-based TBVs in mice, clinical trials have failed to induce robust and long-lived Ab titers, in part due to the poorly immunogenic nature of Pfs25. Using nonhuman primates, we demonstrate that multiple aspects of Pfs25 immunity were enhanced by antigen encapsulation in poly(lactic-co-glycolic acid)-based [(PLGA)-based] synthetic vaccine particles (SVP[Pfs25]) and potent TLR-based adjuvants. SVP[Pfs25] increased Ab titers, Pfs25-specific plasmablasts, circulating memory B cells, and plasma cells in the bone marrow when benchmarked against the clinically tested multimeric form Pfs25-EPA given with GLA-LSQ. SVP[Pfs25] also induced the first reported Pfs25-specific circulating Th1 and Tfh cells to our knowledge. Multivariate correlative analysis indicated several mechanisms for the improved Ab responses. While Pfs25-specific B cells were responsible for increasing Ab titers, T cell responses stimulated increased Ab avidity. The innate immune activation differentially stimulated by the adjuvants revealed a strong correlation between type I IFN polarization, induced by R848 and CpG, and increased Ab half-life and longevity. Collectively, the data identify ways to improve vaccine-induced immunity to poorly immunogenic proteins, both by the choice of antigen and adjuvant formulation, and highlight underlying immunological mechanisms.

Prevalence and Risk Factors Associated with Human Taenia Solium Infections in Mbozi District, Mbeya Region, Tanzania

PubMed Central

Mwanjali, Gloria; Kihamia, Charles; Kakoko, Deodatus Vitalis Conatus; Lekule, Faustin; Ngowi, Helena; Johansen, Maria Vang; Thamsborg, Stig Milan; Willingham, Arve Lee

2013-01-01

Background Taenia solium cysticercosis/taeniosis is emerging as a serious public health and economic problem in many developing countries. This study was conducted to determine prevalence and risk factors of human T. solium infections in Mbeya Region, Tanzania. Methods and Findings A cross-sectional survey was conducted in 13 villages of Mbozi district in 2009. Sera of 830 people (mean 37.9±11.3 years (SD); 43% females) were tested for circulating cysticerci antigen (Ag-ELISA) and antibody (Ab-ELISA). A subset of persons found seropositive by Ag-ELISA underwent computed tomography (CT) scan of the brain for evidence of neurocysticercosis. Stool samples from 820 of the same participants were tested for taeniosis by copro-antigens (copro-Ag-ELISA) and formol-ether concentration technique. Cases of T. solium taeniosis were confirmed serologically by EITB assay (rES38). A questionnaire was used for identification of risk factors. Active cysticercosis by positive Ag-ELISA was found in 139 (16.7%) persons while anti-cysticercal antibodies were detected in 376 (45.3%) persons by Ab-ELISA. Among 55 persons positive for Ag-ELISA undergoing CT scan, 30 (54.6%) were found to have structures in the brain suggestive of neurocysticercosis. Using faecal analysis, 43 (5.2%) stool samples tested positive for taeniosis by copro-Ag-ELISA while Taenia eggs were detected in 9 (1.1%) stool samples by routine coprology. Antibodies specifically against adult T. solium were detected in 34 copro-Ag-ELISA positive participants by EITB (rES38) indicating T. solium taeniosis prevalence of 4.1%. Increasing age and hand washing by dipping in contrast to using running water, were found associated with Ag-ELISA seropositivity by logistic regression. Gender (higher risk in females) and water source were risk factors associated with Ab-ELISA seropositivity. Reported symptoms of chronic severe headaches and history of epileptic seizures were found associated with positive Ag-ELISA (p≤0.05). Conclusion The present study indicates T. solium infection in humans is highly endemic in the southern highlands of Tanzania. PMID:23516650

Circulating gamma delta T cells are activated and depleted during progression of high-grade gliomas: Implications for gamma delta T cell therapy of GBM

USDA-ARS?s Scientific Manuscript database

Glioblastoma multiforme (GBM) remains frustratingly impervious to any existing therapy. We have previously shown that GBM is sensitive to recognition and lysis by ex vivo activated gamma delta T cells, a minor subset of lymphocytes that innately recognize autologous stress-associated target antigens...

Oral fluids as a live-animal sample for evaluating cross-reactivity and cross-protection following intranasal influenza A virus vaccination in pigs

USDA-ARS?s Scientific Manuscript database

In North American swine there are numerous antigenically distinct influenza A virus (IAV) H1 subtypes currently circulating, making vaccine development difficult due to the inability to formulate a vaccine that provides broad cross-protection. Live-attenuated influenza virus (LAIV) vaccines provide ...

Detection of Antigenic Variants of Subtype H3 Swine Influenza A Viruses from Clinical Samples

PubMed Central

Martin, Brigitte E.; Li, Lei; Nolting, Jacqueline M.; Smith, David R.; Hanson, Larry A.

2017-01-01

ABSTRACT A large population of genetically and antigenically diverse influenza A viruses (IAVs) are circulating among the swine population, playing an important role in influenza ecology. Swine IAVs not only cause outbreaks among swine but also can be transmitted to humans, causing sporadic infections and even pandemic outbreaks. Antigenic characterizations of swine IAVs are key to understanding the natural history of these viruses in swine and to selecting strains for effective vaccines. However, influenza outbreaks generally spread rapidly among swine, and the conventional methods for antigenic characterization require virus propagation, a time-consuming process that can significantly reduce the effectiveness of vaccination programs. We developed and validated a rapid, sensitive, and robust method, the polyclonal serum-based proximity ligation assay (polyPLA), to identify antigenic variants of subtype H3N2 swine IAVs. This method utilizes oligonucleotide-conjugated polyclonal antibodies and quantifies antibody-antigen binding affinities by quantitative reverse transcription-PCR (RT-PCR). Results showed the assay can rapidly detect H3N2 IAVs directly from nasal wash or nasal swab samples collected from laboratory-challenged animals or during influenza surveillance at county fairs. In addition, polyPLA can accurately separate the viruses at two contemporary swine IAV antigenic clusters (H3N2 swine IAV-α and H3N2 swine IAV-ß) with a sensitivity of 84.9% and a specificity of 100.0%. The polyPLA can be routinely used in surveillance programs to detect antigenic variants of influenza viruses and to select vaccine strains for use in controlling and preventing disease in swine. PMID:28077698

Specific Antibodies Reacting with SV40 Large T Antigen Mimotopes in Serum Samples of Healthy Subjects

PubMed Central

Tognon, Mauro; Corallini, Alfredo; Manfrini, Marco; Taronna, Angelo; Butel, Janet S.; Pietrobon, Silvia; Trevisiol, Lorenzo; Bononi, Ilaria; Vaccher, Emanuela; Barbanti-Brodano, Giuseppe; Martini, Fernanda; Mazzoni, Elisa

2016-01-01

Simian Virus 40, experimentally assayed in vitro in different animal and human cells and in vivo in rodents, was classified as a small DNA tumor virus. In previous studies, many groups identified Simian Virus 40 sequences in healthy individuals and cancer patients using PCR techniques, whereas others failed to detect the viral sequences in human specimens. These conflicting results prompted us to develop a novel indirect ELISA with synthetic peptides, mimicking Simian Virus 40 capsid viral protein antigens, named mimotopes. This immunologic assay allowed us to investigate the presence of serum antibodies against Simian Virus 40 and to verify whether Simian Virus 40 is circulating in humans. In this investigation two mimotopes from Simian Virus 40 large T antigen, the viral replication protein and oncoprotein, were employed to analyze for specific reactions to human sera antibodies. This indirect ELISA with synthetic peptides from Simian Virus 40 large T antigen was used to assay a new collection of serum samples from healthy subjects. This novel assay revealed that serum antibodies against Simian Virus 40 large T antigen mimotopes are detectable, at low titer, in healthy subjects aged from 18–65 years old. The overall prevalence of reactivity with the two Simian Virus 40 large T antigen peptides was 20%. This new ELISA with two mimotopes of the early viral regions is able to detect in a specific manner Simian Virus 40 large T antigen-antibody responses. PMID:26731525

Antibody response against HERV-W env surface peptides differentiates multiple sclerosis and neuromyelitis optica spectrum disorder.

PubMed

Arru, Giannina; Sechi, Elia; Mariotto, Sara; Farinazzo, Alessia; Mancinelli, Chiara; Alberti, Daniela; Ferrari, Sergio; Gajofatto, Alberto; Capra, Ruggero; Monaco, Salvatore; Deiana, Giovanni A; Caggiu, Elisa; Mameli, Giuseppe; Sechi, Leonardo A; Sechi, Gian Pietro

2017-01-01

A specific humoral immune response against HERV-W envelope surface (env-su) glycoprotein antigens has been reported in serum of patients with multiple sclerosis (MS). However, it has not been evaluated to date in patients with neuromyelitis optica spectrum disorder (NMOSD). The objective of this paper is to investigate whether antibody (Ab) response against HERV-W env-su antigenic peptides differs between NMOSD and MS. Serum samples were collected from 36 patients with NMOSD, 36 patients with MS and 36 healthy control individuals (HCs). An indirect ELISA was set up to detect specific Abs against HERV-W env-su peptides. Our data showed that two antigenic peptides, particularly HERV-Wenv 93-108 and HERV-Wenv 248-262, were statistically significantly present only in serum of MS compared to NMOSD and HCs. Thus, the specific humoral immune response against HERV-W env-su glycoprotein antigens found in MS is widely missing in NMOSD. Increased circulating serum levels of these HERV-W Abs may be suitable as additional biomarkers to better differentiate MS from NMOSD.

B-Lymphocytes Expressing an Ig Specificity Recognizing the Pancreatic β-Cell Autoantigen Peripherin Are Potent Contributors to Type 1 Diabetes Development in NOD Mice

PubMed Central

Leeth, Caroline M.; Racine, Jeremy; Chapman, Harold D.; Arpa, Berta; Carrillo, Jorge; Carrascal, Jorge; Wang, Qiming; Ratiu, Jeremy; Egia-Mendikute, Leire; Rosell-Mases, Estela; Stratmann, Thomas

2016-01-01

Although the autoimmune destruction of pancreatic β-cells underlying type 1 diabetes (T1D) development is ultimately mediated by T cells in NOD mice and also likely in humans, B cells play an additional key pathogenic role. It appears that the expression of plasma membrane–bound Ig molecules that efficiently capture β-cell antigens allows autoreactive B cells that bypass normal tolerance induction processes to be the subset of antigen-presenting cells most efficiently activating diabetogenic T cells. NOD mice transgenically expressing Ig molecules recognizing antigens that are (insulin) or are not (hen egg lysozyme [HEL]) expressed by β-cells have proven useful in dissecting the developmental basis of diabetogenic B cells. However, these transgenic Ig specificities were originally selected for their ability to recognize insulin or HEL as foreign, rather than autoantigens. Thus, we generated and characterized NOD mice transgenically expressing an Ig molecule representative of a large proportion of naturally occurring islet-infiltrating B cells in NOD mice recognizing the neuronal antigen peripherin. Transgenic peripherin-autoreactive B cells infiltrate NOD pancreatic islets, acquire an activated proliferative phenotype, and potently support accelerated T1D development. These results support the concept of neuronal autoimmunity as a pathogenic feature of T1D, and targeting such responses could ultimately provide an effective disease intervention approach. PMID:26961115

Antigenic diversity of H5 highly pathogenic avian influenza viruses of clade 2.3.4.4 isolated in Asia.

PubMed

Ohkawara, Ayako; Okamatsu, Masatoshi; Ozawa, Makoto; Chu, Duc-Huy; Nguyen, Lam Thanh; Hiono, Takahiro; Matsuno, Keita; Kida, Hiroshi; Sakoda, Yoshihiro

2017-05-01

H5 highly pathogenic avian influenza viruses (HPAIV) have spread in both poultry and wild birds since late 2003. Continued circulation of HPAIV in poultry in several regions of the world has led to antigenic drift. In the present study, we analyzed the antigenic properties of H5 HPAIV isolated in Asia using four neutralizing mAbs recognizing hemagglutinin, which were established using A/chicken/Kumamoto/1-7/2014 (H5N8), belonging to clade 2.3.4.4 and also using polyclonal antibodies. Viruses of clades 1.1, 2.3.2.1, 2.3.4, and 2.3.4.4 had different reactivity patterns to the panel of mAbs, thereby indicating that the antigenicity of the viruses of clade 2.3.4.4 were similar but differed from the other clades. In particular, the antigenicity of the viruses of clade 2.3.4.4 differed from those of the viruses of clades 2.3.4 and 2.3.2.1, which suggests that the recent H5 HPAIV have further evolved antigenically divergent. In addition, reactivity of antiserum suggests that the antigenicity of viruses of clade 2.3.4.4 differed slightly among groups A, B, and C. Vaccines are still used in poultry in endemic countries, so the antigenicity of H5 HPAIV should be monitored continually to facilitate control of avian influenza. The panel of mAbs established in the present study will be useful for detecting antigenic drift in the H5 viruses that emerge from the current strains. © 2017 The Societies and John Wiley & Sons Australia, Ltd.

Feeding horses with industrially manufactured pellets with fungal spores to promote nematode integrated control.

PubMed

Hernández, José Ángel; Arroyo, Fabián Leonardo; Suárez, José; Cazapal-Monteiro, Cristiana Filipa; Romasanta, Ángel; López-Arellano, María Eugenia; Pedreira, José; de Carvalho, Luis Manuel Madeira; Sánchez-Andrade, Rita; Arias, María Sol; de Gives, Pedro Mendoza; Paz-Silva, Adolfo

2016-10-15

The usefulness of pellets industrially manufactured with spores of parasiticide fungi as a contribution to integrated nematode control was assessed in grazing horses throughout sixteen months. Two groups of 7 Pura Raza Galega autochthonous horses (G-T and G-P) were dewormed pour-on (1mg Ivermectin/kg bw) at the beginning of the trial, and other group (G-C) remained untreated. The G-P was provided daily with commercial pellets to which was added a mixture of fungal spores during the industrial manufacturing (2×10 6 spores of Mucor circinelloides and same dose of Duddingtonia flagrans/kg), and G-T and G-C received pellets without spores. The efficacy of the parasiticidal strategy was assessed by estimating the reduction in the faecal egg counts (FECR) and in the number of horses shedding eggs in the faeces (PHR), and also the egg reappearance periods (ERP). Blood analyses were performed to identify the changes in the red and white cell patterns. To ascertain if horses developed an IgG humoral response against the fungi, antigenic products collected from M. circinelloides and D. flagrans were exposed to the horse sera by using an ELISA. The faecal elimination of eggs of Parascaris equorum and strongyles ceased 2 weeks after treatment in G-T and G-P, thus the values of FECR and PHR were 100%. No P. equorum-eggs were detected later, and the strongyle egg reappearance period was 28 weeks in G-P, and 8 weeks in G-T. Strongyle egg-output values remained lower than 300 eggs per gram of faeces in the G-P, whereas numbers between 330 and 772 in G-C and G-T were recorded. Normal values for the erythrocytes, haemoglobin and haematocrit in horses consuming pellets with spores were recorded, and lower than normal in the other groups. Sensitization of horses to the fungal species was disproven. It is concluded that feeding horses with pellets industrially manufactured with fungal spores represents a very useful tool to implement an integrated control of helminths affecting horses. This strategy allows a decrease in their risk of infection, aids in reducing the frequency of anthelmintic treatment. Copyright © 2016 Elsevier B.V. All rights reserved.

Description of human AAA by cytokine and immune cell aberrations compared to risk-factor matched controls.

PubMed

Wang, S Keisin; Green, Linden A; Gutwein, Ashley R; Drucker, Natalie A; Motaganahalli, Raghu L; Gupta, Alok K; Fajardo, Andres; Murphy, Michael P

2018-04-28

The pathogenesis driving the formation of abdominal aortic aneurysms continues to be poorly understood. Therefore, we systemically define the cytokine and circulating immune cell environment observed in human abdominal aortic aneurysm compared with risk-factor matched controls. From 2015 to 2017, a total of 274 patients donated blood to the Indiana University Center for Aortic Disease. Absolute concentrations of circulating cytokines were determined, using enzyme-linked immunosorbent assays while the expression of circulating immune cell phenotypes were assayed via flow cytometric analysis. Human abdominal aortic aneurysm is characterized by a significant depletion of the antigen-specific, CD4 + Tr1 regulatory lymphocyte that corresponds to an upregulation of the antigen-specific, inflammatory Th17 cell. We found no differences in the incidence of Treg, B10, and myeloid-derived suppressor regulatory cells. Similarly, no disparities were noted in the following inflammatory cytokines: IL-1β, C-reactive protein, tumor necrosis factor α, interferon γ, and IL-23. However, significant upregulation of the inflammatory cytokines osteopontin, IL-6, and IL-17 were noted. Additionally, no changes were observed in the regulatory cytokines IL-2, IL-4, IL-13, TNF-stimulated gene 6 protein, and prostaglandin E2, but we did observe a significant decrease in the essential regulatory cytokine IL-10. In this investigation, we systematically characterize the abdominal aortic aneurysm-immune environment and present preliminary evidence that faulty immune regulation may also contribute to aneurysm formation and growth. Copyright © 2018 Elsevier Inc. All rights reserved.

Screening for Chlamydia trachomatis in Egyptian women with unexplained infertility, comparing real-time PCR techniques to standard serology tests: case control study.

PubMed

Abdella, Rana M A; Abdelmoaty, Hatem I; Elsherif, Rasha H; Sayed, Ahmed Mahmoud; Sherif, Nadine Alaa; Gouda, Hisham M; El Lithy, Ahmed; Almohamady, Maged; Abdelbar, Mostafa; Hosni, Ahmed Naguib; Magdy, Ahmed; Ma, Youssef

2015-06-02

To study the prevalence of Chlamydia infection in women with primary and secondary unexplained infertility using ELISA technique for antibody detection and real time, fully automated PCR for antigen detection and to explore its association with circulating antisperm antibodies (ASA). A total of 50 women with unexplained infertility enrolled in this case control study and a control group of 44 infertile women with a known cause of infertility. Endocervical specimens were collected for Chlamydia antigen detection using PCR and serum samples for antibodies detection. Circulating anti-sperm antibodies were detected using sperm antibody Latex Agglutination tests. The overall prevalence of Chlamydial infection in unexplained infertility cases as detected by both ELISA and PCR was 40 % (20/50). The prevalence of current Chlamydial genital infection as detected by real-time PCR was only 6.0 % (3/50); two of which were also IgM positive. Prevalence of ASA was 6.0 % (3/50); all were sero-negative for anti-C.trachomatis IgM and were PCR negative. The incidence of Chlamydial infection in Egyptian patients with unexplained infertility is relatively high. In the setting of fertility investigations; screening for anti. C.trachomatis antibodies using ELISA, and treatment of positive cases should be considered. The presence of circulating ASA does not correlate with the presence of old or current Chlamydia infection in women with unexplained infertility.

JAK/STAT signaling in Drosophila muscles controls the cellular immune response against parasitoid infection.

PubMed

Yang, Hairu; Kronhamn, Jesper; Ekström, Jens-Ola; Korkut, Gül Gizem; Hultmark, Dan

2015-12-01

The role of JAK/STAT signaling in the cellular immune response of Drosophila is not well understood. Here, we show that parasitoid wasp infection activates JAK/STAT signaling in somatic muscles of the Drosophila larva, triggered by secretion of the cytokines Upd2 and Upd3 from circulating hemocytes. Deletion of upd2 or upd3, but not the related os (upd1) gene, reduced the cellular immune response, and suppression of the JAK/STAT pathway in muscle cells reduced the encapsulation of wasp eggs and the number of circulating lamellocyte effector cells. These results suggest that JAK/STAT signaling in muscles participates in a systemic immune defense against wasp infection. © 2015 The Authors. Published under the terms of the CC BY 4.0 license.

A liposome-based antigen delivery system using pH-sensitive fusogenic polymers for cancer immunotherapy.

PubMed

Yuba, Eiji; Harada, Atsushi; Sakanishi, Yuichi; Watarai, Shinobu; Kono, Kenji

2013-04-01

Highly pH-sensitive liposomes that deliver antigenic molecules into cytosol through fusion with or destabilization of endosome were prepared by surface modification of egg yolk phosphatidylcholine/dioleoylphosphatidylethanolamine (1/1, mol/mol) liposomes with 3-methylglutarylated poly(glycidol) of linear (MGlu-LPG) or hyperbranched structure (MGlu-HPG). These polymer-modified liposomes were stable at neutral pH, but they became strongly destabilized below pH 6, which corresponds to the pH of endosome. These polymer-modified liposomes were taken up by murine dendritic cells (DCs) more efficiently than the unmodified liposomes were through an endocytic pathway. They introduced entrapped ovalbumin (OVA) molecules into cytosol. Subcutaneous or nasal administration of the polymer-modified liposomes loaded with OVA induced generation of OVA-specific cytotoxic T cells (CTL) much more effectively than the unmodified liposomes loaded with OVA. Furthermore, administration of the polymer-modified OVA-loaded liposomes to mice bearing E.G7-OVA tumor significantly reduced the tumor burden, although the OVA-loaded unmodified liposomes only slightly affected tumor growth. Results suggest that the polymer-modified liposomes with highly pH-sensitive destabilizing property are promising as antigen carriers for efficient cancer immunotherapy. Copyright © 2012 Elsevier Ltd. All rights reserved.

The effect of different adjuvants on immune parameters and protection following vaccination of sheep with a larval-specific antigen of the gastrointestinal nematode, Haemonchus contortus.

PubMed

Piedrafita, David; Preston, Sarah; Kemp, Joanna; de Veer, Michael; Sherrard, Jayne; Kraska, Troy; Elhay, Martin; Meeusen, Els

2013-01-01

It has recently been recognised that vaccine adjuvants play a critical role in directing the nature of a vaccine induced effector response. In the present study, several adjuvants were evaluated for their ability to protect sheep after field vaccination with the larval-specific Haemonchus contortus antigen, HcsL3. Using a suboptimal antigen dose, aluminium adjuvant was shown to reduce the cumulative faecal egg counts (cFEC) and worm burden by 23% and 25% respectively, in agreement with a previous study. The addition of Quil A to the aluminium-adjuvanted vaccine brought cFEC back to control levels. Vaccination with the adjuvant DEAE-dextran almost doubled the protection compared to the aluminium-adjuvanted vaccine resulting in 40% and 41% reduction in cFEC and worm counts compared to controls. Examination of skin responses following i.d. injection of exsheathed L3, revealed that cFEC was negatively correlated with wheal size and tissue eosinophils for the DEAE-dextran and aluminium-adjuvanted groups respectively. These studies have for the first time shown the potential of DEAE-dextran adjuvant for helminth vaccines, and discovered significant cellular correlates of vaccine-induced protection.

Monitoring Calcium in Trout Eggs Exposed to Hydrazine.

DTIC Science & Technology

1981-07-10

differentiation processes (Chapman, 1980). The high level of calcium in the notochord can be attributed to poor circulation which is characteristic of this...healthy muscle of the same individual. The notochord of the 8.0 mg/P group showed a higher calcium level than the control group. The chorion did not...calcium can alter the process . The above would suggest that even if some hydrazine is converted to N2 and thereby produce the gas bubble disease

Antibacterial activity of egg yolk antibody (IgY) against Listeria monocytogenes and preliminary evaluation of its potential for food preservation.

PubMed

Sui, Jianxin; Cao, Limin; Lin, Hong

2011-08-30

Egg yolk antibody (IgY) is a unique type of immunoglobulin found in egg yolks, and many reports have described its ability to inhibit corresponding antigen bacteria. The objective of this study was to evaluate the antibacterial activity of IgY specific to Listeria monocytogenes, an important food pathogen to both humans and animals, as well as its potential use for food preservation. Specific IgY was generated by immunising Leghorn chickens with whole cells of L. monocytogenes, and its inhibitory effect on bacterial growth was tested in liquid medium and food samples. After 8 h of incubation with specific IgY, there was a significant decrease in the growth (absorbance at 600 nm) of L. monocytogenes in comparison with controls. IgY also inhibited the growth of L. monocytogenes inoculated onto fresh or smoked salmon samples. Compared with those of blanks, numbers of L. monocytogenes were reduced by more than 2 log units after 15 days of storage at 6 ± 1 °C in the presence of specific IgY. The results suggest the potential application of specific IgY as a natural antimicrobial agent for food preservation. Copyright © 2011 Society of Chemical Industry.

Influence of antigen on immune complex behavior in mice.

PubMed

Finbloom, D S; Magilavy, D B; Harford, J B; Rifai, A; Plotz, P H

1981-07-01

To explore the possibility that the behavior of immune complexes can, under some circumstances, be directed by the antigen, we have studied the behavior of complexes of identical size made with the glycoproteins, orosomucoid (OR), and ceruloplasmin: or with their desialylated derivatives, asialo-orosomucoid (ASOR) and asialo-ceruloplasmin. Such desialylated proteins are rapidly removed from the circulation by a hepatic cell receptor for galactose, the sugar exposed upon removal of sialic acid. Mixtures of 125I-goat anti-ASOR with either ASOR or OR and mixtures of 125I-rabbit anti-OR with either ASOR or OR form complexes identically. The complexes were separated by density gradient centrifugation and injected intravenously into C3H mice. Blood clearance and hepatic uptake of the OR complexes and ASOR complexes were markedly different. T 1/2 for the goat OR complexes exceeded 300 min, whereas that for the ASOR complexes was 15 min. More detailed studies using rabbit complexes of various sizes revealed that light rabbit complexes behaved similarly to the goat complexes. The light rabbit OR complexes were cleared slowly, with only 18% found in the liver at 60 min, whereas the light rabbit ASOR complexes were cleared much more rapidly, with 62% found within the liver by 30 min. This rapid clearance was completely suppressed by a prior injection of a blocking dose of ASOR, which implies uptake by a galactose-mediated mechanism on hepatocytes. As the size of the rabbit complexes increased, so did the rate of Fc receptor-mediated clearance. Heavy rabbit OR complexes were cleared more rapidly than light OR complexes but not so rapidly as heavy ASOR complexes. The clearance and hepatic uptake of the heavy OR complexes were markedly suppressed by a prior injection of heat-aggregated gamma globulin, a known Fc receptor-blocking agent (45% hepatic uptake without and 6% with aggregated gamma globulin). The heavy rabbit ASOR complexes exhibited inhibition of blood clearance and hepatic uptake by both galactose receptor-blocking and Fc receptor-blocking agents. A blocking dose of ASOR reduced the hepatic uptake at 30 min from 75 to 49%, and heat-aggregated gamma globulin reduced it from 75 to 39%, which suggests that these heavy complexes were removed from the circulation by receptors both for the immunoglobulin and for the antigen. Cell separation studies and autoradiographs confirmed that those complexes cleared primarily by galactose-mediated mechanism were within hepatocytes, and those cleared by Fc receptors were within the nonparenchymal cells of the liver. It seems probable, therefore, the some antigen-antibody complexes may be removed from the circulation via receptors not only for immunoglobulin but also for antigen.

Antigenemia in Patients with Paracoccidioidomycosis: Detection of the 87-Kilodalton Determinant during and after Antifungal Therapy

PubMed Central

Gómez, B. L.; Figueroa, J. I.; Hamilton, A. J.; Diez, S.; Rojas, M.; Tobón, A. M.; Hay, R. J.; Restrepo, A.

1998-01-01

Serological diagnosis and follow-up of paracoccidioidomycosis (PCM) patients have relied mainly on the detection of antibody responses by using techniques such as complement fixation (CF) and immunodiffusion. We recently described a novel inhibition enzyme-linked immunosorbent assay (inh-ELISA) which proved to be useful in the diagnosis of PCM via the detection of an 87-kDa determinant in patient sera (B. L. Gomez, J. I. Figueroa, A. J. Hamilton, B. Ortiz, M. A. Robledo, R. J. Hay, and A. Restrepo, J. Clin. Microbiol. 35:3278–3283, 1997). This test has now been assessed as a means of following up PCM patients. A total of 24 PCM patients, classified according to their clinical presentation (6 with the acute form of the disease, of whom two had AIDS, 12 with the multifocal form of the disease, and 6 with the unifocal form of the disease), were studied. The four human immunodeficiency virus-negative patients with acute PCM showed a statistically significant decrease in circulating antigen levels after the start of antifungal therapy. Antigen levels in this group became negative by our criteria (≤2.3 μg/ml) before week 20 and remained so in three of four of these patients. In contrast, the two AIDS patients who also presented with the acute form of PCM showed no statistically significant decrease in circulating antigen levels even after 68 weeks of therapy. Taken together as a group, the patients with the multifocal form showed a statistically significant decrease in antigenemia after 28 weeks of therapy. In addition, five of six patients with the unifocal form became antigen negative by week 40. Antigen level decrease mirrored clinical cure in the majority of patients in all clinical groups; in contrast, measurement of anti-PCM antibodies via the CF test showed wide fluctuations in titers during the follow-up period. The inh-ELISA for the detection of the 87-kDa Paracoccidioides brasiliensis determinant would appear to be a valuable additional tool in the follow-up of PCM patients. PMID:9774584

Antigen based detection of cystic echinococcosis in buffaloes using ELISA and Dot-EIA.

PubMed

Sangaran, A; Bino Sundar, S T; Latha, Bhaskaran Ravi

2017-03-01

Cystic echinococcosis is caused by the larval stage of the dog tapeworm, Echinococcus granulosus . The disease is recognized as one of the world's major zoonoses affecting human beings and domestic animals apart from its economic and public health importance. Development of the cysts in the intermediate host such as buffaloes occurs in the lungs, liver and other organs. In this study, detection of circulating antigen in the diagnosis of cystic echinococcosis in buffaloes was done using enzyme linked immunosorbent assay and Dot-Enzyme immunoassay (Dot-EIA). The sensitivity and specificity were determined as 89 and 92 % respectively, whereas those of Dot-EIA were determined as 94 and 96 %.

A peptide sequence on carcinoembryonic antigen binds to a 80kD protein on Kupffer cells.

PubMed

Thomas, P; Petrick, A T; Toth, C A; Fox, E S; Elting, J J; Steele, G

1992-10-30

Clearance of carcinoembryonic antigen (CEA) from the circulation is by binding to Kupffer cells in the liver. We have shown that CEA binding to Kupffer cells occurs via a peptide sequence YPELPK representing amino acids 107-112 of the CEA sequence. This peptide sequence is located in the region between the N-terminal and the first immunoglobulin like loop domain. Using native CEA and peptides containing this sequence complexed with a heterobifunctional crosslinking agent and ligand blotting with biotinylated CEA and NCA we have shown binding to an 80kD protein on the Kupffer cell surface. This binding protein may be important in the development of hepatic metastases.

Circulation of influenza B lineages in northern Viet Nam, 2007-2014.

PubMed

Le, Thi Thanh; Pham, Thu Hang; Pham, Thi Hien; Nguyen, Le Khanh Hang; Nguyen, Co Thach; Hoang, Vu Mai Phuong; Tran, Thu Huong; Nguyen, Vu Son; Ngo, Huong Giang; Le, Quynh Mai

2015-01-01

Influenza B viruses circulate throughout Viet Nam, and their activities vary by region. There have been two antigenically distinct lineages of influenza B viruses co-circulating in the past 20 years; however, only one lineage is selected as a component of contemporary trivalent seasonal influenza vaccines. To improve the understanding of circulating influenza B lineages and influenza vaccine mismatches, we report the virus lineages circulating in northern Viet Nam over an eight-year period (2007-2014). Lineages of 331 influenza B viruses were characterized by haemagglutination inhibition assay against standard reference ferret (Yamagata) and sheep (Victoria) antisera. Sequence analysis of the haemagglutinin gene was performed in 64 selected influenza B isolates. The proportion of influenza B lineages changed by year. The Yamagata lineage predominated in 2007, 2008 and 2012; the Victoria lineage predominated in 2009-2014 except 2012. The two lineages showed continuous evolution over time. The Northern Hemisphere's influenza vaccine components were mismatched with the predominant circulating viruses in 2007, 2009 and 2014. The seasonality of influenza B activity is more variable in tropical and subtropical regions than in temperate zones. Our data showed a common co-circulation of both influenza B lineages in northern Viet Nam, and it was difficult to predict which one was the predominant lineage. Quadrivalent influenza vaccines containing both lineages may improve the effectiveness of influenza vaccine programmes in the future.

Genome-wide evolutionary dynamics of influenza B viruses on a global scale

PubMed Central

Langat, Pinky; Bowden, Thomas A.; Edwards, Stephanie; Gall, Astrid; Rambaut, Andrew; Daniels, Rodney S.; Russell, Colin A.; Pybus, Oliver G.; McCauley, John

2017-01-01

The global-scale epidemiology and genome-wide evolutionary dynamics of influenza B remain poorly understood compared with influenza A viruses. We compiled a spatio-temporally comprehensive dataset of influenza B viruses, comprising over 2,500 genomes sampled worldwide between 1987 and 2015, including 382 newly-sequenced genomes that fill substantial gaps in previous molecular surveillance studies. Our contributed data increase the number of available influenza B virus genomes in Europe, Africa and Central Asia, improving the global context to study influenza B viruses. We reveal Yamagata-lineage diversity results from co-circulation of two antigenically-distinct groups that also segregate genetically across the entire genome, without evidence of intra-lineage reassortment. In contrast, Victoria-lineage diversity stems from geographic segregation of different genetic clades, with variability in the degree of geographic spread among clades. Differences between the lineages are reflected in their antigenic dynamics, as Yamagata-lineage viruses show alternating dominance between antigenic groups, while Victoria-lineage viruses show antigenic drift of a single lineage. Structural mapping of amino acid substitutions on trunk branches of influenza B gene phylogenies further supports these antigenic differences and highlights two potential mechanisms of adaptation for polymerase activity. Our study provides new insights into the epidemiological and molecular processes shaping influenza B virus evolution globally. PMID:29284042

The diagnosis of Echinococcus granulosus in dogs.

PubMed

Varcasia, A; Garippa, G; Scala, A

2004-12-01

The problem of diagnosing Echinococcus granulosus in dogs has still only been partially resolved, even after the advent of biotechnology. The eggs of taeniid Cestoda are extremely similar, and thus identification by microscopic examination of the faeces is risky and non-specific. For this reason, Echinococcus granulosus was traditionally diagnosed in dogs ante mortem after an arecoline hydrobromate purge. The faeces were examined macro and microscopically to establish if the adult tapeworm or its proglottids were present. Although this method is 100% specific, it is bio-hazardous and time-consuming, requires trained personnel, and its sensitivity varies. In the 1990s copro-antigens were discovered and characterised. These are released by the adult worm in the faeces. This made it possible to use enzyme-linked immune-adsorbent assay (ELISA) for in vitam diagnosis of Echinococcus granulosus. In recent years several PCR protocols have been published on the identification of Echinococcus granulosus DNA from eggs or from adult parasites and new ways of diagnosing this cestode have been developed.

The transmission of Fasciola spp. to cattle and contamination of grazing areas with Fasciola eggs in the Red River Delta region of Vietnam.

PubMed

Lan Anh, Nguyen Thi; Thanh, Dao Thi Ha; Hoan, Doan Huu; Thuy, Do Thu; Khong, Nguyen Viet; Anderson, Norman

2014-04-01

At four times during November 2010, cattle with infections of Fasciola spp., in two communes of northern Vietnam, were allocated to two equivalent groups. Cattle in one group were treated with triclabendazole. Faecal samples collected monthly from both groups were tested for Fasciola copro-antigens and the presence of Fasciola eggs. Re-infection of treated cattle occurred from early March to late November, coinciding with high weekly totals of rainfall. Contamination of grazing areas by untreated cattle was high and relatively constant throughout the year. However, contamination was reduced to undetectable amounts for 8 to 12 weeks after treatment and even at 20 weeks was only 50% or less of the pre-treatment amounts. Therefore, treatments given in mid-September and again in early April, at the start of the wet season, may be sufficient to prevent contamination of grazing areas and reduce the prevalence and severity of Fasciola infections in cattle.

Epidemiology of Hookworm Infection in Kintampo North Municipality, Ghana: Patterns of Malaria Coinfection, Anemia, and Albendazole Treatment Failure

PubMed Central

Humphries, Debbie; Mosites, Emily; Otchere, Joseph; Twum, Welbeck Amoani; Woo, Lauren; Jones-Sanpei, Hinckley; Harrison, Lisa M.; Bungiro, Richard D.; Benham-Pyle, Blair; Bimi, Langbong; Edoh, Dominic; Bosompem, Kwabena; Wilson, Michael; Cappello, Michael

2011-01-01

A cross-sectional pilot study of hookworm infection was carried out among 292 subjects from 62 households in Kintampo North, Ghana. The overall prevalence of hookworm infection was 45%, peaking in those 11–20 years old (58.5%). In children, risk factors for hookworm infection included coinfection with malaria and increased serum immunoglobulin G reactivity to hookworm secretory antigens. Risk factors for infection in adults included poor nutritional status, not using a latrine, not wearing shoes, and occupation (farming). Although albendazole therapy was associated with an overall egg reduction rate of 82%, 37 subjects (39%) remained infected. Among those who failed therapy, treatment was not associated with a significant reduction in egg excretion, and nearly one-third had higher counts on repeat examination. These data confirm a high prevalence of low-intensity hookworm infection in central Ghana and its association with poor nutritional status. The high rate of albendazole failure raises concern about emerging resistance. PMID:21540391

World Reference Center for Arboviruses.

DTIC Science & Technology

1984-01-01

viral antigen in Avian sera. .. . ... ....... . ... .. . ... . .......... 97 Effect of hibernation of EEE virus circulation and antibody Development...viruses were isolated from a variety of mosquito species collected on several different islands in the Indonesian archipelago (Sumatra, Kalimantan, Java ...vishnui Java 15 Jun 81 7180 Cx. tritaeniorhynchus Java 13 Jul 81 7887 Cx. tritaeniorhynchus Java 26-27 Jul 81 8442 Cx. tritaeniorhynchus Bali 10 Dec 80

A novel liquid-phase piezoelectric immunosensor for detecting Schistosoma japonicum circulating antigen.

PubMed

Wen, Zhili; Wang, Shiping; Wu, Zhaoyang; Shen, Guoli

2011-09-01

A new liquid-phase piezoelectric immunosensor (LP-PEIS), which can detect Schistosoma japonicum (Sj) circulating antigens (SjCAg) quantificationally, was developed. The IgG antibodies were purified from the sera of rabbits which had been infected or immunized by Sj and were immobilized on the surface of piezoelectric quartz crystal in LP-PEIS by staphylococcal protein A (SPA). It was used to detect SjCAg in sera of rabbits which had been infected by Sj in order to acquire some optimum conditions for detecting SjCAg. Finally, the LP-PEIS with optimum conditions was used to detect SjCAg in sera of patients who had been infected by Sj, and was compared with sandwich ELISA. A lot of optimum conditions of LP-PEIS for detecting SjCAg had been acquired. In the detection of patients' sera with acute Schistosomiasis, LP-PEIS has higher positive rate (100%) and lower false positive rate (3.0%) than sandwich ELISA (92.8%, 6.0%). However, there were no significant difference between LP-PEIS and sandwich ELISA. LP-PEIS can quantificationally detect SjCAg in patients' sera as well as sandwich ELISA. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Antibodies Against the Current Influenza A(H1N1) Vaccine Strain Do Not Protect Some Individuals From Infection With Contemporary Circulating Influenza A(H1N1) Virus Strains.

PubMed

Petrie, Joshua G; Parkhouse, Kaela; Ohmit, Suzanne E; Malosh, Ryan E; Monto, Arnold S; Hensley, Scott E

2016-12-15

During the 2013-2014 influenza season, nearly all circulating 2009 pandemic influenza A(H1N1) virus (A[H1N1]pdm09) strains possessed an antigenically important mutation in hemagglutinin (K166Q). Here, we performed hemagglutination-inhibition (HAI) assays, using sera collected from 382 individuals prior to the 2013-2014 season, and we determined whether HAI titers were associated with protection from A(H1N1)pdm09 infection. Protection was associated with HAI titers against an A(H1N1)pdm09 strain possessing the K166Q mutation but not with HAI titers against the current A(H1N1)pdm09 vaccine strain, which lacks this mutation. These data indicate that contemporary A(H1N1)pdm09 strains are antigenically distinct from the current A(H1N1)pdm09 vaccine strain. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Protective Role of Purified Cysteine Proteinases against Fasciola gigantica Infection in Experimental Animals

PubMed Central

Rabia, Ibrahim; Nagy, Faten; Zoheiry, Mona; Diab, Tarek; Zada, Suher

2012-01-01

Fascioliasis is one of the public health problems in the world. Cysteine proteinases (CP) released by Fasciola gigantica play a key role in parasite feeding, migration through host tissues, and in immune evasion. There has been some evidence from several parasite systems that proteinases might have potential as protective antigens against parasitic infections. Cysteine proteinases were purified and tested in vaccine trials of sheep infected with the liver fluke. Multiple doses (2 mg of CP in Freund's adjuvant followed by 3 booster doses 1 mg each at 4 week intervals) were injected intramuscularly into sheep 1 week prior to infect orally with 300 F. gigantica metacercariae. All the sheep were humanely slaughtered 12 weeks after the first immunization. Changes in the worm burden, ova count, and humoral and cellular responses were evaluated. Significant reduction was observed in the worm burden (56.9%), bile egg count (70.7%), and fecel egg count (75.2%). Immunization with CP was also found to be associated with increases of total IgG, IgG1, and IgG2 (P<0.05). Data showed that the serum cytokine levels of pro-inflammatory cytokines, IL-12, IFN-γ, and TNF-α, revealed significant decreases (P<0.05). However, the anti-inflammatory cytokine levels, IL-10, TGF-β, and IL-6, showed significant increases (P<0.05). In conclusion, it has been found that CP released by F. gigantica are highly important candidates for a vaccine antigen because of their role in the fluke biology and host-parasite relationships. PMID:22451733

Protective role of purified cysteine proteinases against Fasciola gigantica infection in experimental animals.

PubMed

El-Ahwany, Eman; Rabia, Ibrahim; Nagy, Faten; Zoheiry, Mona; Diab, Tarek; Zada, Suher

2012-03-01

Fascioliasis is one of the public health problems in the world. Cysteine proteinases (CP) released by Fasciola gigantica play a key role in parasite feeding, migration through host tissues, and in immune evasion. There has been some evidence from several parasite systems that proteinases might have potential as protective antigens against parasitic infections. Cysteine proteinases were purified and tested in vaccine trials of sheep infected with the liver fluke. Multiple doses (2 mg of CP in Freund's adjuvant followed by 3 booster doses 1 mg each at 4 week intervals) were injected intramuscularly into sheep 1 week prior to infect orally with 300 F. gigantica metacercariae. All the sheep were humanely slaughtered 12 weeks after the first immunization. Changes in the worm burden, ova count, and humoral and cellular responses were evaluated. Significant reduction was observed in the worm burden (56.9%), bile egg count (70.7%), and fecel egg count (75.2%). Immunization with CP was also found to be associated with increases of total IgG, IgG(1), and IgG(2) (P<0.05). Data showed that the serum cytokine levels of pro-inflammatory cytokines, IL-12, IFN-γ, and TNF-α, revealed significant decreases (P<0.05). However, the anti-inflammatory cytokine levels, IL-10, TGF-β, and IL-6, showed significant increases (P<0.05). In conclusion, it has been found that CP released by F. gigantica are highly important candidates for a vaccine antigen because of their role in the fluke biology and host-parasite relationships.

Influenza immunization elicits antibodies specific for an egg-adapted vaccine strain.

PubMed

Raymond, Donald D; Stewart, Shaun M; Lee, Jiwon; Ferdman, Jack; Bajic, Goran; Do, Khoi T; Ernandes, Michael J; Suphaphiphat, Pirada; Settembre, Ethan C; Dormitzer, Philip R; Del Giudice, Giuseppe; Finco, Oretta; Kang, Tae Hyun; Ippolito, Gregory C; Georgiou, George; Kepler, Thomas B; Haynes, Barton F; Moody, M Anthony; Liao, Hua-Xin; Schmidt, Aaron G; Harrison, Stephen C

2016-12-01

For broad protection against infection by viruses such as influenza or HIV, vaccines should elicit antibodies that bind conserved viral epitopes, such as the receptor-binding site (RBS). RBS-directed antibodies have been described for both HIV and influenza virus, and the design of immunogens to elicit them is a goal of vaccine research in both fields. Residues in the RBS of influenza virus hemagglutinin (HA) determine a preference for the avian or human receptor, α-2,3-linked sialic acid and α-2,6-linked sialic acid, respectively. Transmission of an avian-origin virus between humans generally requires one or more mutations in the sequences encoding the influenza virus RBS to change the preferred receptor from avian to human, but passage of a human-derived vaccine candidate in chicken eggs can select for reversion to avian receptor preference. For example, the X-181 strain of the 2009 new pandemic H1N1 influenza virus, derived from the A/California/07/2009 isolate and used in essentially all vaccines since 2009, has arginine at position 226, a residue known to confer preference for an α-2,3 linkage in H1 subtype viruses; the wild-type A/California/07/2009 isolate, like most circulating human H1N1 viruses, has glutamine at position 226. We describe, from three different individuals, RBS-directed antibodies that recognize the avian-adapted H1 strain in current influenza vaccines but not the circulating new pandemic 2009 virus; Arg226 in the vaccine-strain RBS accounts for the restriction. The polyclonal sera of the three donors also reflect this preference. Therefore, when vaccines produced from strains that are never passaged in avian cells become widely available, they may prove more capable of eliciting RBS-directed, broadly neutralizing antibodies than those produced from egg-adapted viruses, extending the established benefits of current seasonal influenza immunizations.

Air Pollution Exposure with Fine Dust. Responses in the Pulmonary Vasculature and the Right Heart.

PubMed

Durmus, Nedim; Grunig, Gabriele

2018-04-01

Detrimental effects of air pollution with fine dust (particulate matter ≤2.5 μm in aerodynamic diameter, or PM 2.5 ) on the systemic circulation and the left heart have been studied intensely during the past decade. In comparison, knowledge regarding the effects of exposure to air pollution with PM 2.5 on the pulmonary vasculature and the right heart lags far behind. A report on severe lung disease and right heart failure in coal miners was published nearly 170 years ago. However, today, we still do not have a clear picture of how the effect of air pollution on the pulmonary circulation or the right heart should be viewed from a clinical, mechanistic biological, therapeutic, or economic angle. In the laboratory, we have established a model of immune response-induced vascular remodeling that is significantly worsened by adding PM 2.5 to the intranasal antigen challenge solution. Importantly, the PM 2.5 is given at a concentration that by itself does not induce significant inflammation or pulmonary vascular remodeling. However, when added to antigen, this low-dose PM 2.5 exposure induces severe pulmonary vascular remodeling, significantly increased right ventricular pressures, and significant molecular changes in the right heart. Our data also show that these PM 2.5 -exaggerated responses are dependent on interleukin-13, interleukin-17A, and antigen-specific antibody. The experimental model is being used to address a few questions: 1. Which mechanism protects the animals from severe right ventricular failure despite the severity of the pulmonary artery remodeling? 2. What is the mechanism by which PM 2.5 worsens the response to antigen? 3. How does PM 2.5 exert its effects across the small airways to the small blood vessels? In conclusion, further investigation is urgently needed to understand the effects of exposure to ambient or occupational air pollution on the pulmonary vasculature, because better knowledge could lead to immediate beneficial actions for patients with pulmonary hypertension and persons at risk.

First detection of canine parvovirus type 2b from diarrheic dogs in Himachal Pradesh.

PubMed

Sharma, Shalini; Dhar, Prasenjit; Thakur, Aneesh; Sharma, Vivek; Sharma, Mandeep

2016-09-01

The present study was conducted to detect the presence of canine parvovirus (CPV) among diarrheic dogs in Himachal Pradesh and to identify the most prevalent antigenic variant of CPV based on molecular typing and sequence analysis of VP2 gene. A total of 102 fecal samples were collected from clinical cases of diarrhea or hemorrhagic gastroenteritis from CPV vaccinated or non-vaccinated dogs. Samples were tested using CPV-specific polymerase chain reaction (PCR) targeting VP2 gene, multiplex PCR for detection of CPV-2a and CPV-2b antigenic variants, and a PCR for the detection of CPV-2c. CPV-2b isolate was cultured on Madin-Darby canine kidney (MDCK) cell lines and sequenced using VP2 structural protein gene. Multiple alignment and phylogenetic analysis was done using ClustalW and MEGA6 and inferred using the Neighbor-Joining method. No sample was found positive for the original CPV strain usually present in the vaccine. However, about 50% (52 out of 102) of the samples were found to be positive with CPV-2ab PCR assay that detects newer variants of CPV circulating in the field. In addition, multiplex PCR assay that identifies both CPV-2ab and CPV-2b revealed that CPV-2b was the major antigenic variant present in the affected dogs. A PCR positive isolate of CPV-2b was adapted to grow in MDCK cells and produced characteristic cytopathic effect after 5 th passage. Multiple sequence alignment of VP2 structural gene of CPV-2b isolate (Accession number HG004610) used in the study was found to be similar to other sequenced isolates in NCBI sequence database and showed 98-99% homology. This study reports the first detection of CPV-2b in dogs with hemorrhagic gastroenteritis in Himachal Pradesh and absence of other antigenic types of CPV. Further, CPV-specific PCR assay can be used for rapid confirmation of circulating virus strains under field conditions.

Recombinant ESAT-6-CFP10 Fusion Protein Induction of Th1/Th2 Cytokines and FoxP3 Expressing Treg Cells in Pulmonary TB

PubMed Central

Jackson-Sillah, Dolly; Cliff, Jacqueline M.; Mensah, Gloria Ivy; Dickson, Emmanuel; Sowah, Sandra; Tetteh, John K A.; Addo, Kwasi K.; Ottenhoff, Tom H. M.; Bothamley, Graham; Dockrell, Hazel M.

2013-01-01

Background Early secretory antigenic target 6 (ESAT-6) and culture filtrate protein 10 (CFP-10) are Mycobacterium tuberculosis (Mtb)–specific antigens that are secreted by actively metabolising bacteria and contribute to the virulence of the bacteria. Their ability to induce Treg and Th2 responses, particularly during the first two weeks of treatment, has not been comprehensively examined to date. The purpose of this work was to characterise Th1, Th2 and Treg responses to rESAT-6-CFP10 fusion protein in TB patients before and during the intensive phase of treatment and in healthy M.bovis BCG vaccinated donors. Methods Forty-six newly diagnosed, HIV-negative, smear-positive pulmonary TB patients and 20 healthy donors were recruited in the UK and Ghana. Their peripheral blood mononuclear cells (PBMC) were used in ex vivo ELISPOT and in vitro cultures to identify immunological parameters of interest. Results The study confirmed that protective immune responses to rESAT-6-CFP10 are impaired in active TB but improved during treatment: circulating antigen-specific IL-4-producing T-cells were increased in untreated TB but declined by two weeks of treatment while the circulating antigen-specific IFN-γ producing T cells which showed a transient rise at one week of treatment, persisted at baseline levels at two months of treatment. In vitro T cell proliferation and IFN-γ production were reduced, while IL-4 and CD4+FoxP3+CD25hi cell expression were increased in response to rESAT-6-CFP10 fusion protein in untreated TB. These responses were reversed during early treatment of TB. Conclusions These observations support further investigations into the possible utility of these parameters as markers of active disease and favourable treatment outcomes. PMID:23826366

Circulating Gut-Homing (α4β7+) Plasmablast Responses against Shigella Surface Protein Antigens among Hospitalized Patients with Diarrhea.

PubMed

Sinha, Anuradha; Dey, Ayan; Saletti, Giulietta; Samanta, Pradip; Chakraborty, Partha Sarathi; Bhattacharya, M K; Ghosh, Santanu; Ramamurthy, T; Kim, Jae-Ouk; Yang, Jae Seung; Kim, Dong Wook; Czerkinsky, Cecil; Nandy, Ranjan K

2016-07-01

Developing countries are burdened with Shigella diarrhea. Understanding mucosal immune responses associated with natural Shigella infection is important to identify potential correlates of protection and, as such, to design effective vaccines. We performed a comparative analysis of circulating mucosal plasmablasts producing specific antibodies against highly conserved invasive plasmid antigens (IpaC, IpaD20, and IpaD120) and two recently identified surface protein antigens, pan-Shigella surface protein antigen 1 (PSSP1) and PSSP2, common to all virulent Shigella strains. We examined blood and stool specimens from 37 diarrheal patients admitted to the Infectious Diseases & Beliaghata General Hospital, Kolkata, India. The etiological agent of diarrhea was investigated in stool specimens by microbiological methods and real-time PCR. Gut-homing (α4β7 (+)) antibody-secreting cells (ASCs) were isolated from patient blood by means of combined magnetic cell sorting and two-color enzyme-linked immunosorbent spot (ELISPOT) assay. Overall, 57% (21 of 37) and 65% (24 of 37) of the patients were positive for Shigella infection by microbiological and real-time PCR assays, respectively. The frequency of α4β7 (+) IgG ASC responders against Ipas was higher than that observed against PSSP1 or PSSP2, regardless of the Shigella serotype isolated from these patients. Thus, α4β7 (+) ASC responses to Ipas may be considered an indirect marker of Shigella infection. The apparent weakness of ASC responses to PSSP1 is consistent with the lack of cross-protection induced by natural Shigella infection. The finding that ASC responses to IpaD develop in patients with recent-onset shigellosis indicates that such responses may not be protective or may wane too rapidly and/or be of insufficient magnitude. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Detection of Antigenic Variants of Subtype H3 Swine Influenza A Viruses from Clinical Samples.

PubMed

Martin, Brigitte E; Bowman, Andrew S; Li, Lei; Nolting, Jacqueline M; Smith, David R; Hanson, Larry A; Wan, Xiu-Feng

2017-04-01

A large population of genetically and antigenically diverse influenza A viruses (IAVs) are circulating among the swine population, playing an important role in influenza ecology. Swine IAVs not only cause outbreaks among swine but also can be transmitted to humans, causing sporadic infections and even pandemic outbreaks. Antigenic characterizations of swine IAVs are key to understanding the natural history of these viruses in swine and to selecting strains for effective vaccines. However, influenza outbreaks generally spread rapidly among swine, and the conventional methods for antigenic characterization require virus propagation, a time-consuming process that can significantly reduce the effectiveness of vaccination programs. We developed and validated a rapid, sensitive, and robust method, the polyclonal serum-based proximity ligation assay (polyPLA), to identify antigenic variants of subtype H3N2 swine IAVs. This method utilizes oligonucleotide-conjugated polyclonal antibodies and quantifies antibody-antigen binding affinities by quantitative reverse transcription-PCR (RT-PCR). Results showed the assay can rapidly detect H3N2 IAVs directly from nasal wash or nasal swab samples collected from laboratory-challenged animals or during influenza surveillance at county fairs. In addition, polyPLA can accurately separate the viruses at two contemporary swine IAV antigenic clusters (H3N2 swine IAV-α and H3N2 swine IAV-ß) with a sensitivity of 84.9% and a specificity of 100.0%. The polyPLA can be routinely used in surveillance programs to detect antigenic variants of influenza viruses and to select vaccine strains for use in controlling and preventing disease in swine. Copyright © 2017 American Society for Microbiology.

Placental restriction of fetal growth reduces cutaneous responses to antigen after sensitization in sheep.

PubMed

Wooldridge, Amy L; Bischof, Robert J; Meeusen, Els N; Liu, Hong; Heinemann, Gary K; Hunter, Damien S; Giles, Lynne C; Kind, Karen L; Owens, Julie A; Clifton, Vicki L; Gatford, Kathryn L

2014-04-01

Prenatal and early childhood exposures are implicated as causes of allergy, but the effects of intrauterine growth restriction on immune function and allergy are poorly defined. We therefore evaluated effects of experimental restriction of fetal growth on immune function and allergic sensitization in adolescent sheep. Immune function (circulating total red and white blood cells, neutrophils, lymphocytes, monocytes, eosinophils, and basophils, and the antibody response to Clostridial vaccination) and responses to house dust mite (HDM) allergen and ovalbumin (OVA) antigen sensitization (specific total Ig, IgG1, and IgE antibodies, and cutaneous hypersensitivity) were investigated in adolescent sheep from placentally restricted (PR, n = 23) and control (n = 40) pregnancies. Increases in circulating HDM-specific IgE (P = 0.007) and OVA-specific IgE (P = 0.038) were greater in PR than control progeny. PR did not alter total Ig, IgG1, or IgM responses to either antigen. PR increased OVA-specific but not HDM-specific IgA responses in females only (P = 0.023). Multiple birth increased Ig responses to OVA in a sex-specific manner. PR decreased the proportion of positive cutaneous hypersensitivity responders to OVA at 24 h (P = 0.030) but had no effect on cutaneous responses to HDM. Acute wheal responses to intradermal histamine correlated positively with birth weight in singletons (P = 0.023). Intrauterine growth restriction may suppress inflammatory responses in skin downstream of IgE induction, without impairment in antibody responses to a nonpolysaccharide vaccine. Discord between cutaneous and IgE responses following sensitization suggests new mechanisms for prenatal allergy programming.

Circulating filarial antigen in the hydrocele fluid from individuals living in a bancroftian filariasis area - Recife, Brazil: detected by the monoclonal antibody Og4C3-assay.

PubMed

Rocha, Abraham; Lima, Guilherme; Medeiros, Zulma; Aguiar-Santos, Ana; Alves, Sandra; Montarroyos, Ulisses; Oliveira, Paula; Béliz, Fátima; Netto, Maria José; Furtado, André

2004-02-01

The purpose of this study was to examine the circulating filarial antigen (CFA) detected by the monoclonal antibody (mAb) Og4C3-ELISA in paired samples of serum and hydrocele fluid from 104 men with hydrocele, living in an endemic area of Wuchereria bancrofti. Nocturnal blood specimens were filtered and examined for microfilariae (MF) and ultrasound was used in order to identify the presence of adult worms (the filaria dance sign - FDS) in the lymphatic vessels of the scrotal area. Four groups were selected according to their parasitological status: group I - 71 MF- and FDS-; group II - 21 MF+ and FDS+; group III - 10 MF- and FDS+ and group IV- 2 MF+ and FDS-. CFA was identified simultaneously (fluid and serum) in 11 (15.5%), 21 (100%), 3 (30%), and 1 (50%) in groups I, II, III, and IV, respectively. In despite of high CFA+ level (antigen Og4C3) units/ml, the Geometrical Mean (GM) = 2696) in the sera of these 36/104 paired samples, when compared to the hydrocele fluid, (GM = 1079), showed a very good correlation between the CFA level in the serum and CFA level in the fluid (r = 0.731). CFA level in the serum of the 23 microfilaremics (groups II and IV) was extremely high (GM = 4189) and was correlated with MF density (r = 0.442). These findings report for the first time the potential alternative use of the hydrocele fluid to investigate CFA using the mAb Og4C3-ELISA.

Reassortment and evolution of current human influenza A and B viruses.

PubMed

Xu, Xiyan; Lindstrom, Stephen E; Shaw, Michael W; Smith, Catherine B; Hall, Henrietta E; Mungall, Bruce A; Subbarao, Kanta; Cox, Nancy J; Klimov, Alexander

2004-07-01

During the 2001-2002 influenza season, human influenza A (H1N2) reassortant viruses were detected globally. The hemagglutinin (HA) of these H1N2 viruses was similar to that of the A/New Caledonia/20/99 (H1N1) vaccine strain both antigenically and genetically, while their neuraminidase (NA) was antigenically and genetically related to that of recent human influenza H3N2 reference viruses such as A/Moscow/10/99. All six internal genes of the H1N2 reassortants originated from an H3N2 virus. After being detected only in eastern Asia during the past 10 years, Influenza B/Victoria/2/87 lineage viruses reappeared in many countries outside of Asia in 2001. Additionally, reassortant influenza B viruses possessing an HA similar to that of B/Shandong/7/97, a recent B/Victoria/2/87 lineage reference strain, and an NA closely related to that of B/Sichuan/379/99, a recent B/Yamagata/16/88 lineage reference strain, were isolated globally and became the predominant influenza B epidemic strain. The current influenza vaccine is expected to provide good protection against H1N2 viruses because it contains A/New Caledonia/20/99 (H1N1) and A/Panama/2007/99 (H3N2) like viruses whose H1 HA or N2 NA are antigenically similar to those of recent circulating H1N2 viruses. On the other hand, widespread circulation of influenza B Victoria lineage viruses required inclusion of a strain from this lineage in influenza vaccines for the 2002-2003 season.

Lymphatic System in Cardiovascular Medicine.

PubMed

Aspelund, Aleksanteri; Robciuc, Marius R; Karaman, Sinem; Makinen, Taija; Alitalo, Kari

2016-02-05

The mammalian circulatory system comprises both the cardiovascular system and the lymphatic system. In contrast to the blood vascular circulation, the lymphatic system forms a unidirectional transit pathway from the extracellular space to the venous system. It actively regulates tissue fluid homeostasis, absorption of gastrointestinal lipids, and trafficking of antigen-presenting cells and lymphocytes to lymphoid organs and on to the systemic circulation. The cardinal manifestation of lymphatic malfunction is lymphedema. Recent research has implicated the lymphatic system in the pathogenesis of cardiovascular diseases including obesity and metabolic disease, dyslipidemia, inflammation, atherosclerosis, hypertension, and myocardial infarction. Here, we review the most recent advances in the field of lymphatic vascular biology, with a focus on cardiovascular disease. © 2016 American Heart Association, Inc.

Seasonal influenza vaccines.

PubMed

Fiore, Anthony E; Bridges, Carolyn B; Cox, Nancy J

2009-01-01

Influenza vaccines are the mainstay of efforts to reduce the substantial health burden from seasonal influenza. Inactivated influenza vaccines have been available since the 1940s and are administered via intramuscular injection. Inactivated vaccines can be given to anyone six months of age or older. Live attenuated, cold-adapted influenza vaccines (LAIV) were developed in the 1960s but were not licensed in the United States until 2003, and are administered via nasal spray. Both vaccines are trivalent preparations grown in eggs and do not contain adjuvants. LAIV is licensed for use in the United States for healthy nonpregnant persons 2-49 years of age.Influenza vaccination induces antibodies primarily against the major surface glycoproteins hemagglutinin (HA) and neuraminidase (NA); antibodies directed against the HA are most important for protection against illness. The immune response peaks at 2-4 weeks after one dose in primed individuals. In previously unvaccinated children <9 years of age, two doses of influenza vaccine are recommended, as some children in this age group have limited or no prior infections from circulating types and subtypes of seasonal influenza. These children require both an initial priming dose and a subsequent booster dose of vaccine to mount a protective antibody response.The most common adverse events associated with inactivated vaccines are sore arm and redness at the injection site; systemic symptoms such as fever or malaise are less commonly reported. Guillian-Barré Syndrome (GBS) was identified among approximately 1 per 100,000 recipients of the 1976 swine influenza vaccine. The risk of influenza vaccine-associated GBS from seasonal influenza vaccine is thought to be at most approximately 1-2 cases per 1 million vaccinees, based on a few studies that have found an association; other studies have found no association.The most common adverse events associated with LAIV are nasal congestion, headache, myalgias or fever. Studies of the safety of LAIV among young children suggest an increased risk of wheezing in some young children, and the vaccine is not recommended for children younger than 2 years old, ages 2-4 old with a history of recurrent wheezing or reactive airways disease, or older persons who have any medical condition that confers an increased risk of influenza-related complications.The effectiveness of influenza vaccines is related predominantly to the age and immune competence of the vaccinee and the antigenic relatedness of vaccine strains to circulating strains. Vaccine effectiveness in preventing laboratory-confirmed influenza illness when the vaccine strains are well matched to circulating strains is 70-90% in randomized, placebo-controlled trials conducted among children and young healthy adults, but is lower among elderly or immunocompromised persons. In years with a suboptimal match, vaccine benefit is likely to be lower, although the vaccine can still provide substantial benefit, especially against more severe outcomes. Live, attenuated influenza vaccines have been most extensively studied among children, and have been shown to be more effective than inactivated vaccines in several randomized controlled trials among young children.Influenza vaccination is recommended in the United States for all children six months or older, all adults 50 years or older, all persons with chronic medical conditions, and pregnant women, and contacts of these persons, including healthcare workers. The global disease burden of influenza is substantial, and the World Health Organization has indicated that member states should evaluate the cost-effectiveness of introducing influenza vaccination into national immunization programs. More research is needed to develop more effective seasonal influenza vaccines that provide long-lasting immunity and broad protection against strains that differ antigenically from vaccine viruses.

African-American Men with Gleason Score 3+3=6 Prostate Cancer Produce Less Prostate Specific Antigen than Caucasian Men: A Potential Impact on Active Surveillance.

PubMed

Kryvenko, Oleksandr N; Balise, Raymond; Soodana Prakash, Nachiketh; Epstein, Jonathan I

2016-02-01

We assess the difference in prostate specific antigen production between African-American and Caucasian men with Gleason score 3+3=6 prostate cancer. We measured tumor volume in 414 consecutive radical prostatectomies from men with National Comprehensive Cancer Network(®) low risk prostate cancer (348 Caucasian, 66 African-American) who had Gleason score 3+3=6 disease at radical prostatectomy. We then compared clinical presentation, pathological findings, prostate specific antigen, prostate specific antigen density and prostate specific antigen mass (an absolute amount of prostate specific antigen in patient's circulation) between African-American and Caucasian men. The t-test and Wilcoxon rank sum were used for comparison of means. African-American and Caucasian men had similar clinical findings based on age, body mass index and prostate specific antigen. There were no statistically significant differences between the dominant tumor nodule volume and total tumor volume (mean 0.712 vs 0.665 cm(3), p=0.695) between African-American and Caucasian men. Prostates were heavier in African-American men (mean 55.4 vs 46.3 gm, p <0.03). Despite the significantly greater weight of benign prostate tissue contributing to prostate specific antigen in African-American men, prostate specific antigen mass was not different from that of Caucasian men (mean 0.55 vs 0.558 μg, p=0.95). Prostate specific antigen density was significantly less in African-American men due to larger prostates (mean 0.09 vs 0.105, p <0.02). African-American men with Gleason score 3+3=6 prostate cancer produce less prostate specific antigen than Caucasian men. African-American and Caucasian men had equal serum prostate specific antigen and prostate specific antigen mass despite significantly larger prostates in African-American men with all other parameters, particularly total tumor volume, being the same. This finding has practical implications in T1c cases diagnosed with prostate cancer due to prostate specific antigen screening. Lowering the prostate specific antigen density threshold in African-American men may account for this disparity, particularly in selecting patients for active surveillance programs. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

T-Cell Surface Antigens and sCD30 as Biomarkers of the Risk of Rejection in Solid Organ Transplantation.

PubMed

Wieland, Eberhard; Shipkova, Maria

2016-04-01

T-cell activation is a characteristic of organ rejection. T cells, located in the draining lymph nodes of the transplant recipient, are faced with non-self-molecules presented by antigen presenting cells and become activated. Activated T cells are characterized by up-regulated surface antigens, such as costimulatory molecules, adhesion molecules, chemokine receptors, and major histocompatibility complex class II molecules. Surface antigen expression can be followed by flow cytometry using monoclonal antibodies in either cell function assays using donor-specific or nonspecific stimulation of isolated cells or whole blood and without stimulation on circulating lymphocytes. Molecules such as CD30 can be proteolytically cleaved off the surface of activated cells in vivo, and the determination of the soluble protein (sCD30) in serum or plasma is performed by immunoassays. As promising biomarkers for rejection and long-term transplant outcome, CD28 (costimulatory receptor for CD80 and CD86), CD154 (CD40 ligand), and sCD30 (tumor necrosis factor receptor superfamily, member 8) have been identified. Whereas cell function assays are time-consuming laboratory-developed tests which are difficult to standardize, commercial assays are frequently available for soluble proteins. Therefore, more data from clinical trials have been published for sCD30 compared with the surface antigens on activated T cells. This short review summarizes the association between selected surface antigens and immunosuppression, and rejection in solid organ transplantation.

Chemical Basis for Qualitative and Quantitative Differences Between ABO Blood Groups and Subgroups: Implications for Organ Transplantation.

PubMed

Jeyakanthan, M; Tao, K; Zou, L; Meloncelli, P J; Lowary, T L; Suzuki, K; Boland, D; Larsen, I; Burch, M; Shaw, N; Beddows, K; Addonizio, L; Zuckerman, W; Afzali, B; Kim, D H; Mengel, M; Shapiro, A M J; West, L J

2015-10-01

Blood group ABH(O) carbohydrate antigens are carried by precursor structures denoted type I-IV chains, creating unique antigen epitopes that may differ in expression between circulating erythrocytes and vascular endothelial cells. Characterization of such differences is invaluable in many clinical settings including transplantation. Monoclonal antibodies were generated and epitope specificities were characterized against chemically synthesized type I-IV ABH and related glycans. Antigen expression was detected on endomyocardial biopsies (n = 50) and spleen (n = 11) by immunohistochemical staining and on erythrocytes by flow cytometry. On vascular endothelial cells of heart and spleen, only type II-based ABH antigens were expressed; type III/IV structures were not detected. Type II-based ABH were expressed on erythrocytes of all blood groups. Group A1 and A2 erythrocytes additionally expressed type III/IV precursors, whereas group B and O erythrocytes did not. Intensity of A/B antigen expression differed among group A1 , A2 , A1 B, A2 B and B erythrocytes. On group A2 erythrocytes, type III H structures were largely un-glycosylated with the terminal "A" sugar α-GalNAc. Together, these studies define qualitative and quantitative differences in ABH antigen expression between erythrocytes and vascular tissues. These expression profiles have important implications that must be considered in clinical settings of ABO-incompatible transplantation when interpreting anti-ABO antibodies measured by hemagglutination assays with reagent erythrocytes. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

Influenza A virus vaccines for swine.

PubMed

Vincent, Amy L; Perez, Daniel R; Rajao, Daniela; Anderson, Tavis K; Abente, Eugenio J; Walia, Rasna R; Lewis, Nicola S

2017-07-01

Economic losses due to influenza A virus (IAV) infections are substantial and a global problem, ranking among the top three major health challenges in the swine industry. Currently, H1 and H3 subtypes circulate in pigs globally associated with different combinations of N1 and N2 subtypes; however, the origin, gene constellation, and antigenic makeup of IAV vary greatly on different continents. Vaccination is one means of mitigating the effects of IAV disease, and vaccines are most effective if the strains included closely match the currently circulating strains in pigs. Genetic analyses provide panoramic views of the virus landscape at the sequence level and, thus, can aid in the selection of well-matched swine IAV vaccine strains, but is not sufficient alone. Additionally, a major challenge in selecting appropriate swine IAV vaccine strains is the co-circulation of multiple lineages of viruses in the same region, requiring multivalent or broadly cross-reacting antigens. Due to this complex IAV ecology in swine, new vaccination strategies and vaccine platforms are needed. The hemagglutinin (HA) viral protein is the major target of neutralizing antibodies, which are widely considered to be correlated with protection. Virus variants that are not recognized by previously elicited antibodies can render traditional vaccines that primarily elicit humoral responses ineffective, and therefore result in the need for vaccine strain reformulation and re-vaccination. In the future, new vaccine platforms may be on the market that will provide alternative options to those currently available. Nonetheless, a collaborative approach is needed to improve IAV vaccine strain selection for use in swine. Published by Elsevier B.V.

Mathematical analysis of a multiple strain, multi-locus-allele system for antigenically variable infectious diseases revisited.

PubMed

Cherif, Alhaji

2015-09-01

Many important pathogens such as HIV/AIDS, influenza, malaria, dengue and meningitis generally exist in phenotypically distinct serotypes that compete for hosts. Models used to study these diseases appear as meta-population systems. Herein, we revisit one of the multiple strain models that have been used to investigate the dynamics of infectious diseases with co-circulating serotypes or strains, and provide analytical results underlying the numerical investigations. In particular, we establish the necessary conditions for the local asymptotic stability of the steady states and for the existence of oscillatory behaviors via Hopf bifurcation. In addition, we show that the existence of discrete antigenic forms among pathogens can either fully or partially self-organize, where (i) strains exhibit no strain structures and coexist or (ii) antigenic variants sort into non-overlapping or minimally overlapping clusters that either undergo the principle of competitive exclusion exhibiting discrete strain structures, or co-exist cyclically. Copyright © 2015. Published by Elsevier Inc.

Semi-Quantitative Scoring of an Immunochromatographic Test for Circulating Filarial Antigen

PubMed Central

Chesnais, Cédric B.; Missamou, François; Pion, Sébastien D. S.; Bopda, Jean; Louya, Frédéric; Majewski, Andrew C.; Weil, Gary J.; Boussinesq, Michel

2013-01-01

The value of a semi-quantitative scoring of the filarial antigen test (Binax Now Filariasis card test, ICT) results was evaluated during a field survey in the Republic of Congo. One hundred and thirty-four (134) of 774 tests (17.3%) were clearly positive and were scored 1, 2, or 3; and 11 (1.4%) had questionable results. Wuchereria bancrofti microfilariae (mf) were detected in 41 of those 133 individuals with an ICT test score ≥ 1 who also had a night blood smear; none of the 11 individuals with questionable ICT results harbored night mf. Cuzick's test showed a significant trend for higher microfilarial densities in groups with higher ICT scores (P < 0.001). The ICT scores were also significantly correlated with blood mf counts. Because filarial antigen levels provide an indication of adult worm infection intensity, our results suggest that semi-quantitative reading of the ICT may be useful for grading the intensity of filarial infections in individuals and populations. PMID:24019435

Influenza Vaccine Research funded by the European Commission FP7-Health-2013-Innovation-1 project.

PubMed

Liu, Heng; Frijlink, Henderik W; Huckriede, Anke; van Doorn, Eva; Schmidt, Ed; Leroy, Odile; Rimmelzwaan, Guus; McCullough, Keneth; Whelan, Mike; Hak, Eelko

2016-11-21

Due to influenza viruses continuously displaying antigenic variation, current seasonal influenza vaccines must be updated annually to include the latest predicted strains. Despite all the efforts put into vaccine strain selection, vaccine production, testing, and administration, the protective efficacy of seasonal influenza vaccines is greatly reduced when predicted vaccine strains antigenically mismatch with the actual circulating strains. Moreover, preparing for a pandemic outbreak is a challenge, because it is unpredictable which strain will cause the next pandemic. The European Commission has funded five consortia on influenza vaccine development under the Seventh Framework Programme for Research and Technological Development (FP7) in 2013. The call of the EU aimed at developing broadly protective influenza vaccines. Here we review the scientific strategies used by the different consortia with respect to antigen selection, vaccine delivery system, and formulation. The issues related to the development of novel influenza vaccines are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

T suppressor cells are required for the maintenance of the antigen-induced B-cell unresponsive state in humans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benveniste, E.; Stevens, R.H.

1983-04-01

Tetanus toxoid immunization of humans generates circulating B cells which secrete IgG anti-tetanus toxoid antibodies (IgG-Tet) when stimulated in vitro with T cells and pokeweed mitogen (PWM). A unique property of these cells is the inhibition of maturation into antibody-secreting plasma cells following a 1-hr in vitro pulse with tetanus toxoid. Studies were undertaken to determine if different T-cell subsets could modulate the in vitro generated B-cell unresponsive state. The addition of OKT4+/OKT8- cells to antigen-treated B cells resulted in a partial reversal of the antigen-induced inhibition of IgG-Tet synthesis. The addition of OKT4-/OKT8+ cells to the treated B cellsmore » caused a suppression of IgG-Tet synthesis comparable to that seen in cultures containing unfractionated T cells. These results indicate that (1) the B-cell unresponsive state generated by antigen treatment is not absolute, (2) the degree of B-cell unresponsiveness results from a balance of suppressor and helper signals, and (3) T-suppressor cells need to be present to induce and maintain the B-cell unresponsive state.« less

Traditional and New Influenza Vaccines

PubMed Central

Wong, Sook-San

2013-01-01

SUMMARY The challenges in successful vaccination against influenza using conventional approaches lie in their variable efficacy in different age populations, the antigenic variability of the circulating virus, and the production and manufacturing limitations to ensure safe, timely, and adequate supply of vaccine. The conventional influenza vaccine platform is based on stimulating immunity against the major neutralizing antibody target, hemagglutinin (HA), by virus attenuation or inactivation. Improvements to this conventional system have focused primarily on improving production and immunogenicity. Cell culture, reverse genetics, and baculovirus expression technology allow for safe and scalable production, while adjuvants, dose variation, and alternate routes of delivery aim to improve vaccine immunogenicity. Fundamentally different approaches that are currently under development hope to signal new generations of influenza vaccines. Such approaches target nonvariable regions of antigenic proteins, with the idea of stimulating cross-protective antibodies and thus creating a “universal” influenza vaccine. While such approaches have obvious benefits, there are many hurdles yet to clear. Here, we discuss the process and challenges of the current influenza vaccine platform as well as new approaches that are being investigated based on the same antigenic target and newer technologies based on different antigenic targets. PMID:23824369

Rabies virus vaccines: is there a need for a pan-lyssavirus vaccine?

PubMed

Evans, Jennifer S; Horton, Daniel L; Easton, Andrew J; Fooks, Anthony R; Banyard, Ashley C

2012-12-14

All members of the lyssavirus genus are capable of causing disease that invariably results in death following the development of clinical symptoms. The recent detection of several novel lyssavirus species across the globe, in different animal species, has demonstrated that the lyssavirus genus contains a greater degree of genetic and antigenic variation than previously suspected. The divergence of species within the genus has led to a differentiation of lyssavirus isolates based on both antigenic and genetic data into two, and potentially a third phylogroup. Critically, from both a human and animal health perspective, current rabies vaccines appear able to protect against lyssaviruses classified within phylogroup I. However no protection is afforded against phylogroup II viruses or other more divergent viruses. Here we review current knowledge regarding the diversity and antigenicity of the lyssavirus glycoprotein. We review the degree of cross protection afforded by rabies vaccines, the genetic and antigenic divergence of the lyssaviruses and potential mechanisms for the development of novel lyssavirus vaccines for use in areas where divergent lyssaviruses are known to circulate, as well as for use by those at occupational risk from these pathogens. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

Correlates of protection, antigen delivery and molecular epidemiology: basics for designing an HIV vaccine.

PubMed

Wagner, R; Shao, Y; Wolf, H

1999-03-26

Major obstacles in the development of HIV vaccines are the high variability of the virus and its complex interaction with the immune system. Recent studies demonstrated, that CTLs recognizing highly conserved epitopes in the group-specific antigen are capable of controlling HIV-replication in long-term nonprogressors. Necessary consequences for novel vaccine concepts are the presentation of a large repertoire of antigenic sites as well as the stimulation of different effectors of the immune system. Accordingly, different types of recombinant HIV-1 virus-like particles (VLPs) have been constructed stimulating the induction of neutralizing antibodies and HIV-specific CD8-positive CTL responses in preclinical studies. With respect to future vaccine trials, HIV vaccine formulations may need to be tailored to the local strains circulating within a geographical region. The expert group of the joint United Nations Programme on AIDS recently identified Yunnan, a southwestern province of China, as a region, in which the HIV epidemic is starting to gain speed, resembling to the situation in Thailand 10 years ago. A molecular clone of a representative virus strain is now available for the development of innovative antigen delivery systems aiming to be evaluated in future clinical vaccine trials throughout this area.

Typing of the rabies virus in Chile, 2002-2008.

PubMed

Yung, V; Favi, M; Fernandez, J

2012-12-01

In Chile, dog rabies has been controlled and insectivorous bats have been identified as the main rabies reservoir. This study aimed to determine the rabies virus (RABV) variants circulating in the country between 2002 and 2008. A total of 612 RABV isolates were tested using a panel with eight monoclonal antibodies against the viral nucleoprotein (N-mAbs) for antigenic typing, and a product of 320-bp of the nucleoprotein gene was sequenced from 99 isolates. Typing of the isolates revealed six different antigenic variants but phylogenetic analysis identified four clusters associated with four different bat species. Tadarida brasiliensis bats were confirmed as the main reservoir. This methodology identified several independent rabies enzootics maintained by different species of insectivorous bats in Chile.

A simple method to recover Norovirus from fresh produce with large sample size by using histo-blood group antigens conjugated magnetic beads re-circulating immunomagnetic separation system

USDA-ARS?s Scientific Manuscript database

Noroviruses (NoV) annually cause millions of cases of gastrointestinal disease in the United States. Although NoV outbreaks are generally associated with raw shellfish, particularly oysters, outbreaks have also been known to occur from other common-source food-borne vehicles such as lettuce, frozen...

The pharmacokinetics of, and humoral responses to, antigen delivered by microencapsulated liposomes.

PubMed

Cohen, S; Bernstein, H; Hewes, C; Chow, M; Langer, R

1991-12-01

The feasibility of creating a s.c. depot for sustained protein delivery with the goal of enhancing antigen immunogenicity was investigated. The depot was designed as antigen-laden liposomes of hydrogenated egg phosphatidylcholine and cholesterol (1:1 molar ratio) encapsulated in alginate-poly(L-lysine) microcapsules and evaluated using iodinated bovine serum albumin (BSA) as a model antigen. The in vivo release behavior of the liposomes and microencapsulated liposomes (MELs) was evaluated from the BSA serum concentration profiles after s.c. injection into rats and the pharmacokinetic parameters of 125I-labeled BSA appearance after s.c. or i.v. injections of BSA in saline. Maximal BSA concentrations were detected 11 h after s.c. injection in all rats. The BSA serum concentrations decreased rapidly in rats injected with BSA in saline or Freund's adjuvant and less rapidly in rats injected with BSA in liposomes or MELs. Four to 5 weeks after injection, BSA-associated radioactivity was detected only in sera of rats injected with BSA in liposomes or MELs. Fifty days after injection, 50% of the originally injected BSA was recovered form the s.c. sites of rats injected with BSA in MELs; no radioactivity was recovered from the other three groups of rats. The antigen-reactive antibody levels induced in rats immunized with BSA in MELs were 2- to 3-fold higher than those obtained in rats immunized with BSA in liposomes, saline, or Freund's adjuvant. More significantly, high antibody levels were maintained for more than 150 days after a single injection of BSA in MELs, suggesting that MELs can serve as a long-term single-dose immunization vehicle.

Diagnostic strategies to reveal covert infections with intestinal helminths in dogs.

PubMed

Adolph, Chris; Barnett, Sharon; Beall, Melissa; Drake, Jason; Elsemore, David; Thomas, Jennifer; Little, Susan

2017-11-30

Intestinal helminths are common in dogs in the United States, particularly non-treated dogs in animal shelters, but surveys by fecal flotation may underestimate their prevalence. To determine the prevalence of intestinal helminths and evaluate the ability of fecal flotation and detection of nematode antigen to identify those infections, contents of the entire gastrointestinal tract of 97 adult (>1year) dogs previously identified for humane euthanasia at two animal control shelters in northeastern Oklahoma, USA, were screened. All helminths recovered were washed in saline and fixed prior to enumeration and identification to genus and species. Fecal samples from each dog were examined by passive sodium nitrate (SG 1.33) and centrifugal sugar solution (SG 1.25) flotation. Fecal antigen detection assays were used to confirm the presence of nematode antigen in frozen fecal samples from 92 dogs. Necropsy examination revealed Ancylostoma caninum in 45/97 (46.4%), Toxocara canis in 11/97 (11.3%), Trichuris vulpis in 38/97 (39.2%), Dipylidium caninum in 48/97 (49.5%), and Taenia sp. in 7/97 (7.2%) dogs. Passive fecal flotation identified 38/45 (84.4%) A. caninum, 6/11 (54.5%) T. canis, 26/38 (68.4%) T. vulpis, 2/48 (4.2%) D. caninum, and 1/7 (14.3%) Taenia sp. infections, while centrifugal flotation combined with antigen detection assays identified A. caninum in 97.7% (43/44), T. canis in 77.8% (7/9), and T. vulpis in 83.3% (30/36) of infected dogs based on necropsy recovery of nematodes. Taken together, these data indicate that detection of nematode antigen is a useful adjunct to microscopic examination of fecal samples for parasite eggs, and that this approach can improve diagnostic sensitivity for intestinal nematode infections in dogs. Copyright © 2017 Elsevier B.V. All rights reserved.

Taenia solium Human Cysticercosis: A Systematic Review of Sero-epidemiological Data from Endemic Zones around the World

PubMed Central

Coral-Almeida, Marco; Gabriël, Sarah; Abatih, Emmanuel Nji; Praet, Nicolas; Benitez, Washington; Dorny, Pierre

2015-01-01

Background Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC) in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies, apparent prevalence of human taeniasis and risk factors for HCC from endemic communities in order to understand the differences in exposure to the parasite and active infections with T. solium metacestodes in endemic areas around the world. Methods Three databases were used to search sero-epidemiological data from community-based studies conducted between 1989 and 2014 in cysticercosis endemic communities worldwide. The search focused on data obtained from T. solium circulating antigen detection by monoclonal antibody-based sandwich ELISA and/or T. solium antibody seroprevalence determined by Enzyme-linked Immunoelectrotransfer Blot (EITB). A meta-analysis was performed per continent. Principal Findings A total of 39,271 participants from 19 countries, described in 37 articles were studied. The estimates for the prevalence of circulating T. solium antigens for Africa, Latin America and Asia were: 7.30% (95% CI [4.23–12.31]), 4.08% (95% CI [2.77–5.95]) and 3.98% (95% CI [2.81–5.61]), respectively. Seroprevalence estimates of T. solium antibodies were 17.37% (95% CI [3.33–56.20]), 13.03% (95% CI [9.95–16.88]) and 15.68% (95% CI [10.25–23.24]) respectively. Taeniasis reported prevalences ranged from 0 (95% CI [0.00–1.62]) to 17.25% (95% CI [14.55–20.23]). Significance A significant variation in the sero-epidemiological data was observed within each continent, with African countries reporting the highest apparent prevalences of active infections. Intrinsic factors in the human host such as age and immunity were main determinants for the occurrence of infections, while exposure was mostly related to environmental factors which varied from community to community. PMID:26147942

Taenia solium Human Cysticercosis: A Systematic Review of Sero-epidemiological Data from Endemic Zones around the World.

PubMed

Coral-Almeida, Marco; Gabriël, Sarah; Abatih, Emmanuel Nji; Praet, Nicolas; Benitez, Washington; Dorny, Pierre

2015-01-01

Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC) in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies, apparent prevalence of human taeniasis and risk factors for HCC from endemic communities in order to understand the differences in exposure to the parasite and active infections with T. solium metacestodes in endemic areas around the world. Three databases were used to search sero-epidemiological data from community-based studies conducted between 1989 and 2014 in cysticercosis endemic communities worldwide. The search focused on data obtained from T. solium circulating antigen detection by monoclonal antibody-based sandwich ELISA and/or T. solium antibody seroprevalence determined by Enzyme-linked Immunoelectrotransfer Blot (EITB). A meta-analysis was performed per continent. A total of 39,271 participants from 19 countries, described in 37 articles were studied. The estimates for the prevalence of circulating T. solium antigens for Africa, Latin America and Asia were: 7.30% (95% CI [4.23-12.31]), 4.08% (95% CI [2.77-5.95]) and 3.98% (95% CI [2.81-5.61]), respectively. Seroprevalence estimates of T. solium antibodies were 17.37% (95% CI [3.33-56.20]), 13.03% (95% CI [9.95-16.88]) and 15.68% (95% CI [10.25-23.24]) respectively. Taeniasis reported prevalences ranged from 0 (95% CI [0.00-1.62]) to 17.25% (95% CI [14.55-20.23]). A significant variation in the sero-epidemiological data was observed within each continent, with African countries reporting the highest apparent prevalences of active infections. Intrinsic factors in the human host such as age and immunity were main determinants for the occurrence of infections, while exposure was mostly related to environmental factors which varied from community to community.

Genetic analysis and characterization of wild poliovirus type 1 during sustained transmission in a population with >95% vaccine coverage, Israel 2013.

PubMed

Shulman, Lester M; Martin, Javier; Sofer, Danit; Burns, Cara C; Manor, Yossi; Hindiyeh, Musa; Gavrilin, Eugene; Wilton, Thomas; Moran-Gilad, Jacob; Gamzo, Ronni; Mendelson, Ella; Grotto, Itamar

2015-04-01

Israel has >95% polio vaccine coverage with the last 9 birth cohorts immunized exclusively with inactivated polio vaccine (IPV). Using acute flaccid paralysis and routine, monthly countrywide environmental surveillance, no wild poliovirus circulation was detected between 1989 and February 2013, after which wild type 1 polioviruses South Asia genotype (WPV1-SOAS) have persistently circulated in southern Israel and intermittently in other areas without any paralytic cases as determined by intensified surveillance of environmental and human samples. We aimed to characterize antigenic and neurovirulence properties of WPV1-SOAS silently circulating in a highly vaccinated population. WPV1-SOAS capsid genes from environmental and stool surveillance isolates were sequenced, their neurovirulence was determined using transgenic mouse expressing the human poliovirus receptor (Tg21-PVR) mice, and their antigenicity was characterized by in vitro neutralization using human sera, epitope-specific monoclonal murine anti-oral poliovirus vaccine (OPV) antibodies, and sera from IPV-immunized rats and mice. WPV1 amino acid sequences in neutralizing epitopes varied from Sabin 1 and Mahoney, with little variation among WPV1 isolates. Neutralization by monoclonal antibodies against 3 of 4 OPV epitopes was lost. Three-fold lower geometric mean titers (Z = -4.018; P < .001, Wilcoxon signed-rank test) against WPV1 than against Mahoney in human serum correlated with 4- to 6-fold lower neutralization titers in serum from IPV-immunized rats and mice. WPV1-SOAS isolates were neurovirulent (50% intramuscular paralytic dose in Tg21-PVR mice: log10(7.0)). IPV-immunized mice were protected against WPV1-induced paralysis. Phenotypic and antigenic profile changes of WPV1-SOAS may have contributed to the intense silent transmission, whereas the reduced neurovirulence may have contributed to the absence of paralytic cases in the background of high population immunity. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Phenotypic and Functional Alterations in Circulating Memory CD8 T Cells with Time after Primary Infection.

PubMed

Martin, Matthew D; Kim, Marie T; Shan, Qiang; Sompallae, Ramakrishna; Xue, Hai-Hui; Harty, John T; Badovinac, Vladimir P

2015-10-01

Memory CD8 T cells confer increased protection to immune hosts upon secondary viral, bacterial, and parasitic infections. The level of protection provided depends on the numbers, quality (functional ability), and location of memory CD8 T cells present at the time of infection. While primary memory CD8 T cells can be maintained for the life of the host, the full extent of phenotypic and functional changes that occur over time after initial antigen encounter remains poorly characterized. Here we show that critical properties of circulating primary memory CD8 T cells, including location, phenotype, cytokine production, maintenance, secondary proliferation, secondary memory generation potential, and mitochondrial function change with time after infection. Interestingly, phenotypic and functional alterations in the memory population are not due solely to shifts in the ratio of effector (CD62Llo) and central memory (CD62Lhi) cells, but also occur within defined CD62Lhi memory CD8 T cell subsets. CD62Lhi memory cells retain the ability to efficiently produce cytokines with time after infection. However, while it is was not formally tested whether changes in CD62Lhi memory CD8 T cells over time occur in a cell intrinsic manner or are due to selective death and/or survival, the gene expression profiles of CD62Lhi memory CD8 T cells change, phenotypic heterogeneity decreases, and mitochondrial function and proliferative capacity in either a lymphopenic environment or in response to antigen re-encounter increase with time. Importantly, and in accordance with their enhanced proliferative and metabolic capabilities, protection provided against chronic LCMV clone-13 infection increases over time for both circulating memory CD8 T cell populations and for CD62Lhi memory cells. Taken together, the data in this study reveal that memory CD8 T cells continue to change with time after infection and suggest that the outcome of vaccination strategies designed to elicit protective memory CD8 T cells using single or prime-boost immunizations depends upon the timing between antigen encounters.

[The characteristics of epidemic influenza A and B virus strains circulating in Russia during the 2007-2008 season].

PubMed

Ivanova, V T; Trushakova, S V; Oskerko, T A; Shevchenko, E S; Kolobukhina, L V; Vartanian, R V; Beliakova, N V; Iatsyshina, S B; Feodoritova, E L; Zueva, N D; Burtseva, E I

2009-01-01

In 2007-2008 in Russia, the epidemic upsurge of influenza morbidity was caused by the active circulation of influenza A(H1N1, A(H3N2), and B viruses. The center for Ecology and Epidemiology of Influenza studied 334 epidemic strains. The results of a comparative study of the svirus specificity of commercial test systems (AmpliSens Influenza virus A/B and AmpliSens Influenza virus A/H5N1) for the polymerase chain reaction diagnosis and virological assays, including virus isolation, revealed their high correlation, which confirms that they may be expensively used to monitor the circulation of influenza viruses in the Russian Federation. All the strains were isolated in the MDCK cell culture. Influenza A(H1N1) viruses (n = 127) were antigenic variants of the reference strains A/Solomon Islands/3/06 and A/Brisbane/59107. Influenza A(H3N2) viruses (n = 49) were antigenic variants of the reference strains A/Wisconsin/67/05 and A/Brisbane/10/08. One hundred and fifty seven Influenza B strains were drift variants of the reference strains B/Florida/4/06 and B/Shanghai/361/02 of lineage B/Yamagata/16/88 and one strain, a variant of Malaysia/2506/04 related to lineage B/victoria/2/87. The isolates interacted actively with human 0(I) blood group erythrocytes and much more weakly with chicken ones. All study influenza A(H1N1) viruses (n = 74) preserved their sensitivity to rimantadine while 24 (77%) of the 31 study influenza A(H3N2) virus strains were resistant. A study of the time course of changes in the generation of antibodies in the donor sera obtained in Moscow and the Moscow Region in different periods of the epidemic process revealed an increase in antibodies to the reference influenza A and B virus strains circulating in this period.

Pathophysiology of HIV related thrombocytopenia: an analysis of 41 patients.

PubMed Central

Domínguez, A; Gamallo, G; Garcia, R; Lopez-Pastor, A; Peña, J M; Vazquez, J J

1994-01-01

AIM--To analyse the pathogenic mechanism of HIV related thrombocytopenia. METHODS--Forty one patients with thrombocytopenia and HIV-1 infection were investigated over two years. Anticardiolipin antibodies were measured using an enzyme linked immunosorbent assay and antiplatelet antibodies were measured using an immunocapture technique. Tests for VDRL, C3 and C4, antinuclear antibodies and rheumatoid factor were also carried out in all patients and 80 control subjects (HIV-1 positive but non-thrombocytopenic). Indiumoxine labelled platelets were transfused in 13 patients. P24 antigen were also measured in 12 bone marrow aspirates. RESULTS--Antiplatelet antibodies and circulating immune complexes were found exclusively in the thrombocytopenic group; values for antiplatelet antibodies and circulating immune complexes were both higher in homosexual and bisexual patients. Three kinds of pattern were observed using 111 In-labelled platelets: splenic (n = 10); hepatic (n = 2); and destruction of bone marrow in just one case. The two most influential factors in the sequestration pattern were antiplatelet antibodies in the splenic uptake and circulating immune complexes in the hepatic and marrow sequestration. All patients, except three, had decreased platelet recovery. In those patients with a CD4 lymphocyte count of less than 200 x 10(6) cells/l the recovery was clearly greater (53%) than in patients who had more than 200 x 10(6) /l (28%). Finally, in seven of the 12 patients who were chosen for immunohistochemical study, p24 antigen was detected in the megakaryocytes, verifying that HIV-1 infects such cells. CONCLUSIONS--The pathogenic mechanism of HIV related thrombocytopenia is probably multifaceted. Antiplatelet antibodies and circulating immune complexes would cause peripheral destruction in the spleen, liver, and bone marrow, in that order; and, on the other hand, there would be an ineffective immune thrombopoiesis and direct infection of the megakaryocytes which could cause a change in the function and maturity of these cells. PMID:7829697

Matrix and Backstage: Cellular Substrates for Viral Vaccines

PubMed Central

Jordan, Ingo; Sandig, Volker

2014-01-01

Vaccines are complex products that are manufactured in highly dynamic processes. Cellular substrates are one critical component that can have an enormous impact on reactogenicity of the final preparation, level of attenuation of a live virus, yield of infectious units or antigens, and cost per vaccine dose. Such parameters contribute to feasibility and affordability of vaccine programs both in industrialized countries and developing regions. This review summarizes the diversity of cellular substrates for propagation of viral vaccines from primary tissue explants and embryonated chicken eggs to designed continuous cell lines of human and avian origin. PMID:24732259

Real-time association rate constant measurement using combination tapered fiber-optic biosensor (CTFOB) dip-probes

NASA Astrophysics Data System (ADS)

Simmonds, Boris; Wang, Chun-Wei; Kapoor, Rakesh

2010-02-01

This document reports a novel method of measuring association rate constant (ka) for antibody-antigen interaction using evanescent wave-based combination tapered fiber-optic biosensor (CTFOB) dip-probes. The method was demonstrated by measuring association rate constant for bovine serum albumin (BSA) and anti-BSA antibody interaction. "Direct method" was used for detection; goat anti-BSA "capture" antibodies were immobilized on the probe surfaces while the antigen (BSA) was directly labeled with Alexa 488 dye. The probes were subsequently submerged in 3nM Labeled BSA in egg albumin (1 mg/ml). The fluorescence signal recorded was proportional to BSA anti-BSA conjugates and continuous signal was acquired suing a fiber optic spectrometer (Ocean Optics, Inc.). A 476 nm diode laser was use as an excitation source. Association constant was estimated from a plot of signal as a function of time. Measured association rate constant ka for the binding of BSA with anti-BSA at room temperature is (8.33 +/- 0.01) x 104 M-1s-1.

Cross-reactivity of Toxocariasis with Crude Antigen of Toxascaris leonina Larvae by ELISA.

PubMed

Jin, Yan; Shen, Chenghua; Huh, Sun; Choi, Min-Ho; Hong, Sung-Tae

2015-05-01

Roundworms of Toxocara canis and Toxascaris leonina are common gastrointestinal helminths of canids over the world. Humans are infected with T. canis larvae through ingestion of infective eggs in contaminated environments or larvae by consumption of raw or uncooked meat or livers. Recently, patients of clinically diagnosed toxocariasis are increasing and require correct diagnosis in Korea. The present study investigated serological cross-reactivity between crude antigens of T. canis (TCLA) and T. leonina (TLLA) larvae. We collected serum specimens from 177 toxocariasis patients who were clinically suspected in the Seoul National University Hospital and 115 healthy controls. An ELISA method for toxocariasis was used to evaluate diagnostic efficacy of TLLA for serodiagnosis of human toxocariasis. The IgG ELISA using TLLA gave 14 (14.3%) positives of 98 TCLA positive specimens among 177 suspected toxocariasis patients. Most of them showed high absorbances with TCLA. In conclusion, there is a partial cross reaction between serum specimens of toxocariasis and TLLA.

Diagnosis of schistosomiasis japonica with interfacial co-assembly-based multi-channel electrochemical immunosensor arrays

NASA Astrophysics Data System (ADS)

Deng, Wangping; Xu, Bin; Hu, Haiyan; Li, Jianyong; Hu, Wei; Song, Shiping; Feng, Zheng; Fan, Chunhai

2013-05-01

Schistosomiasis control remains to be an important and challenging task in the world. However, lack of quick, simple, sensitive and specific sero-diagnostic test is still a hurdle in the control practice. The commonly employed enzyme-linked immuno-sorbent assay (ELISA) relies on the native soluble egg antigen (SEA) that is limited in supply. Here we developed an electrochemical immunosensor array (ECISA) assay with an interfacial co-assembly strategy. A recombinant Schistosoma japonicum (Sj) calcium-binding protein (SjE16) was used as a principal antigen, while the SEA as a minor, co-assembling agent, with a ratio of 8:1 (SjE16: SEA, Sj16EA), which was co-immobilized on a disposable 16-channel screen-printed carbon electrode array. A portable electrochemical detector was employed to detect antibodies in serum samples. The sensitivity of ECISA reached 100% with minimal cross-reactions. Therefore, we have demonstrated that this rapid, sensitive and specific ECISA technique has the potential to perform large-scale on-site screening of Sj infection.

Circulation of influenza B lineages in northern Viet Nam, 2007–2014

PubMed Central

Le, Thi Thanh; Pham, Thu Hang; Pham, Thi Hien; Nguyen, Le Khanh Hang; Hoang, Vu Mai Phuong; Tran, Thu Huong; Nguyen, Vu Son; Ngo, Huong Giang

2015-01-01

Introduction Influenza B viruses circulate throughout Viet Nam, and their activities vary by region. There have been two antigenically distinct lineages of influenza B viruses co-circulating in the past 20 years; however, only one lineage is selected as a component of contemporary trivalent seasonal influenza vaccines. To improve the understanding of circulating influenza B lineages and influenza vaccine mismatches, we report the virus lineages circulating in northern Viet Nam over an eight-year period (2007–2014). Methods Lineages of 331 influenza B viruses were characterized by haemagglutination inhibition assay against standard reference ferret (Yamagata) and sheep (Victoria) antisera. Sequence analysis of the haemagglutinin gene was performed in 64 selected influenza B isolates. Results The proportion of influenza B lineages changed by year. The Yamagata lineage predominated in 2007, 2008 and 2012; the Victoria lineage predominated in 2009–2014 except 2012. The two lineages showed continuous evolution over time. The Northern Hemisphere’s influenza vaccine components were mismatched with the predominant circulating viruses in 2007, 2009 and 2014. Discussion The seasonality of influenza B activity is more variable in tropical and subtropical regions than in temperate zones. Our data showed a common co-circulation of both influenza B lineages in northern Viet Nam, and it was difficult to predict which one was the predominant lineage. Quadrivalent influenza vaccines containing both lineages may improve the effectiveness of influenza vaccine programmes in the future. PMID:26798557

LOCAL ORGAN HYPERSENSITIVENESS

PubMed Central

Seegal, David; Seegal, Beatrice Carrier

1931-01-01

1. Rabbit eyes sensitized with guinea pig red blood cells or fresh egg white respond with an inflammatory reaction following the intravenous injection of the homologous antigen, but not the heterologous. 2. Two-tenths of 1.0 cc. of a multiple antigen containing ten separate ingredients, or in other words, 0.02 cc. of each foreign protein, when introduced into the rabbit's anterior chamber, is sufficient to produce an altered ocular reactivity such that when 1 cc. of one of the ten antigens is introduced intravenously the eye shows hyperemia of the iris and conjunctiva with more or less edema and lacrimation during the next 24 hours. 3. For as long as 8 months after sensitization eyes will respond with an inflammatory reaction following the intravenous injection of fractions of the total antigen. 4. Repeated daily intravenous injections of a single antigen usually produce no reaction in the sensitized eye after the first few days. Injection of different antigens intravenously on succeeding days produces a continued sterile inflammatory process in the sensitized eye. After the total number of single antigens has been injected, repetition of these injections now fails to produce a similar response. Instead, the eye reaction is at a much lower level and the inflammatory response is manifested only to a few of the antigens injected intravenously. 5. Unless massive doses of antigen are used to desensitize, permanent desensitization of the eye has not occurred in animals which have been followed for at least 8 months. Animals may develop maximal eye responses following repeated intravenous injections of the same antigen, if sufficient time has elapsed between injections. Nevertheless, the eye reactions which can be elicited 6 or 7 months after sensitization are less intense than the initial responses. 6. The ability of the eye inflammation to light up following the intravenous injection of homologous antigen is not due to an initial tissue injury as proven by the fact that the reaction is specific and anterior chambers injured with typhoid vaccine, iodine, saline, glycerine, or albolene will not respond subsequently when the various proteins used for sensitization of the other eyes are injected intravenously. 7. It has been impossible to demonstrate sensitivity in the eye by the intravenous shocking route until at least the 5th day following introduction of the antigen into the anterior chamber. 8. The eye reaction can be produced by the subcutaneous as well as the intravenous injection of antigen. 9. Rabbits vary considerably in the intensity of the eye reaction which can be elicited in them, but only rarely was an animal found which failed completely to give a reaction. PMID:19869914

Circulating dendritic cell precursors in chronic kidney disease: a cross-sectional study.

PubMed

Paul, Katharina; Kretzschmar, Daniel; Yilmaz, Atilla; Bärthlein, Barbara; Titze, Stephanie; Wolf, Gunter; Busch, Martin

2013-12-10

Dendritic cells (DC) are professional antigen-presenting cells in the immune system. They patrol the blood as circulating dendritic cell precursors (DCP). Decreased blood DCP count has been shown to be related to atherosclerotic plaque burden. Since chronic kidney disease (CKD) is associated with chronic inflammation and increased cardiovascular risk, the aim of our study was to investigate a potential effect of CKD on circulating DCP numbers especially in patients with a history of cardiovascular disease. The number of circulating myeloid (mDCP), plasmacytoid (pDCP), and total DCP (tDCP) was analysed by flow cytometry in 245 patients with CKD stage 3 (with and without known cardiovascular events) and 85 coronary healthy controls. In addition, data were compared with a historical group of 130 patients with known coronary artery disease (CAD). Compared to controls, patients with CKD 3 revealed a significant decrease in circulating mDCP (-29%), pDCP (-43%), and tDCP (-38%) (P < 0.001, respectively). Compared with CAD-patients, the decrease in circulating DCP in CKD was comparable or even more pronounced indicating a potential role for DCP in cardiovascular risk potentiation due to CKD. Based on previous findings in CAD, the marked decrease of DCP in CKD implicates a potential role for DCP as a mediator of cardiovascular disease. Whether DCP in CKD may act as new cardiovascular biomarkers needs to be established in future prospective trials.

Temporal distribution and genetic variants in influenza A(H1N1)pdm09 virus circulating in Mexico, seasons 2012 and 2013.

PubMed

Canche-Pech, Jose Reyes; Conde-Ferraez, Laura; Puerto-Solis, Marylin; Gonzalez-Losa, Refugio; Granja-Pérez, Pilar; Villanueva-Jorge, Salha; Chan-Gasca, Maria; Gómez-Carballo, Jesus; López-Ochoa, Luisa; Jiménez-Delgadillo, Bertha; Rodríguez-Sánchez, Iram; Ramírez-Prado, Jorge; Ayora-Talavera, Guadalupe

2017-01-01

The 2012 and 2013 annual influenza epidemics in Mexico were characterized by presenting different seasonal patterns. In 2012 the A(H1N1)pdm09 virus caused a high incidence of influenza infections after a two-year period of low circulation; whereas the 2013 epidemic presented circulation of the A(H1N1)pdm09 virus throughout the year. We have characterized the molecular composition of the Hemagglutinin (HA) and Neuraminidase (NA) genes of the A(H1N1)pdm09 virus from both epidemic seasons, emphasizing the genetic characteristics of viruses isolated from Yucatan in Southern Mexico. The molecular analysis of viruses from the 2012 revealed that all viruses from Mexico were predominantly grouped in clade 7. Strikingly, the molecular characterization of viruses from 2013 revealed that viruses circulating in Yucatan were genetically different to viruses from other regions of Mexico. In fact, we identified the occurrence of two genetic variants containing relevant mutations at both the HA and NA surface antigens. There was a difference on the temporal circulation of each genetic variant, viruses containing the mutations HA-A141T / NA-N341S were detected in May, June and July; whereas viruses containing the mutations HA-S162I / NA-L206S circulated in August and September. We discuss the significance of these novel genetic changes.

Identification of Amino Acid Substitutions Supporting Antigenic Change of Influenza A(H1N1)pdm09 Viruses

PubMed Central

Koel, Björn F.; Mögling, Ramona; Chutinimitkul, Salin; Fraaij, Pieter L.; Burke, David F.; van der Vliet, Stefan; de Wit, Emmie; Bestebroer, Theo M.; Rimmelzwaan, Guus F.; Osterhaus, Albert D. M. E.; Smith, Derek J.; Fouchier, Ron A. M.

2015-01-01

ABSTRACT The majority of currently circulating influenza A(H1N1) viruses are antigenically similar to the virus that caused the 2009 influenza pandemic. However, antigenic variants are expected to emerge as population immunity increases. Amino acid substitutions in the hemagglutinin protein can result in escape from neutralizing antibodies, affect viral fitness, and change receptor preference. In this study, we constructed mutants with substitutions in the hemagglutinin of A/Netherlands/602/09 in an attenuated backbone to explore amino acid changes that may contribute to emergence of antigenic variants in the human population. Our analysis revealed that single substitutions affecting the loop that consists of amino acid positions 151 to 159 located adjacent to the receptor binding site caused escape from ferret and human antibodies elicited after primary A(H1N1)pdm09 virus infection. The majority of these substitutions resulted in similar or increased replication efficiency in vitro compared to that of the virus carrying the wild-type hemagglutinin and did not result in a change of receptor preference. However, none of the substitutions was sufficient for escape from the antibodies in sera from individuals that experienced both seasonal and pandemic A(H1N1) virus infections. These results suggest that antibodies directed against epitopes on seasonal A(H1N1) viruses contribute to neutralization of A(H1N1)pdm09 antigenic variants, thereby limiting the number of possible substitutions that could lead to escape from population immunity. IMPORTANCE Influenza A viruses can cause significant morbidity and mortality in humans. Amino acid substitutions in the hemagglutinin protein can result in escape from antibody-mediated neutralization. This allows the virus to reinfect individuals that have acquired immunity to previously circulating strains through infection or vaccination. To date, the vast majority of A(H1N1)pdm09 strains remain antigenically similar to the virus that caused the 2009 influenza pandemic. However, antigenic variants are expected to emerge as a result of increasing population immunity. We show that single amino acid substitutions near the receptor binding site were sufficient to escape from antibodies specific for A(H1N1)pdm09 viruses but not from antibodies elicited in response to infections with seasonal A(H1N1) and A(H1N1)pdm09 viruses. This study identified substitutions in A(H1N1)pdm09 viruses that support escape from population immunity but also suggested that the number of potential escape variants is limited by previous exposure to seasonal A(H1N1) viruses. PMID:25609810

[Influenza surveillance in nine consecutive seasons, 2003-2012: results from National Influenza Reference Laboratory, Istanbul Faculty Of Medicine, Turkey].

PubMed

Akçay Ciblak, Meral; Kanturvardar Tütenyurd, Melis; Asar, Serkan; Tulunoğlu, Merve; Fındıkçı, Nurcihan; Badur, Selim

2012-10-01

Influenza is a public health problem that affects 5-20% of the world population annually causing high morbidity and mortality especially in risk groups. In addition to determining prevention and treatment strategies with vaccines and antivirals, surveillance data plays an important role in combat against influenza. Surveillance provides valuable data on characteristics of influenza activity, on types, sub-types, antigenic properties and antiviral resistance profile of circulating viruses in a given region. The first influenza surveillance was initiated as a pilot study in 2003 by now named National Influenza Reference Laboratory, Istanbul Faculty of Medicine. Surveillance was launched at national level by Ministry of Health in 2004 and two National Influenza Laboratories, one in Istanbul and the other in Ankara, have been conducting surveillance in Turkey. Surveillance data obtained for nine consecutive years, 2003-2012, by National Influenza Reference Laboratory in Istanbul Faculty of Medicine have been summarized in this report. During 2003-2012 influenza surveillance seasons, a total of 11.077 nasal swabs collected in viral transport medium were sent to the National Influenza Reference Laboratory, Istanbul for analysis. Immun-capture ELISA followed by MDCK cell culture was used for detection of influenza viruses before 2009 and real-time RT-PCR was used thereafter. Antigenic characterizations were done by hemagglutination inhibition assay with the reactives supplied by World Health Organization. Analysis of the results showed that influenza B viruses have entered the circulation in 2005-2006 seasons, and have contributed to the epidemics at increasing rates every year except in the 2009 pandemic season. Influenza B Victoria and Yamagata lineages were cocirculating for two seasons. For other seasons either lineage was in circulation. Antigenic characterization revealed that circulating B viruses matched the vaccine composition either partially or totally for only three seasons. Influenza A(H1N1) and A(H3N2) subtypes were in circulation since the beginning of the surveillance in 2003-2004 season either alone or in cocirculation. After the 2009 pandemic, A(H1N1) viruses were replaced by A(H1N1)pdm09. A(H1N1) and A(H1N1)pdm09 viruses matched the vaccine composition for all seasons. However, A(H3N2) viruses matched the vaccine composition in only three out of eight seasons. Analysis of the data revealed that, (a) influenza season has extended in Turkey and it lasts through May; (b) influenza peaks in different age groups depending on the season; (c) every year a different influenza type and subtype dominates the season; (d) influenza B has been circulating with increasing rate especially in the past six seasons. Influenza surveillance provides valuable data that can guide policy makers in developing programmes to prevent and reduce influenza burden. Therefore, addition of hospital based surveillance to general practice based sentinel surveillance will take influenza surveillance one step ahead in meeting the need for collecting data on severe influenza cases which will allow assessment of burden of influenza more reliably.

Competitive and double antibody sandwich ELISA for the quantification of lactoferrins by using monoclonal and chicken egg yolk IgY antibodies.

PubMed

Sunwoo, Hoon; Gujral, Naiyana; Suresh, Mavanur

2011-01-01

Two effective competitive and double antibody sandwich ELISA based on monoclonal (MAb) and chicken egg yolk IgY antibodies were developed to determine lactoferrin (LF) content in infant and milk formulas. Leghorn laying hens were immunized with purified bovine and human LFs to produce anti-bovine LF and anti-human LF IgY antibody in the egg yolk. After 5-8 weeks of the immunization, anti-LF IgY was extracted and analyzed by ELISA. Specific IgY antibodies against LFs cross reacted with human and bovine LFs, examined by ELISA and western-blot assay. Such cross-reactivity suggested the presence of common antigenic determinants between human and bovine LFs. An indirect competitive ELISA was preferred to quantify LF in milk and infant formulas, since the range of detection is 3.125-50 μg/mL, which is broader compared to the biotinylated ELISA system (5-50 ng/mL). As per the indirect competitive ELISA system, IgY at a concentration of the 150 μg/mL was incubated with various concentrations of bovine LF ranged from 0.003-100 μg/mL. The immunoassay was used to estimate the total bovine LF content in the milk samples and infant formulas, ranging from 49.28-80.96 μg/mL and 29.92-60.00 μg/mL, respectively.

B-Cell Responses to Pregnancy-Restricted and -Unrestricted Plasmodium falciparum Erythrocyte Membrane Protein 1 Antigens in Ghanaian Women Naturally Exposed to Malaria Parasites

PubMed Central

Ampomah, Paulina; Stevenson, Liz; Ofori, Michael F.; Barfod, Lea

2014-01-01

Protective immunity to Plasmodium falciparum malaria acquired after natural exposure is largely antibody mediated. IgG-specific P. falciparum EMP1 (PfEMP1) proteins on the infected erythrocyte surface are particularly important. The transient antibody responses and the slowly acquired protective immunity probably reflect the clonal antigenic variation and allelic polymorphism of PfEMP1. However, it is likely that other immune-evasive mechanisms are also involved, such as interference with formation and maintenance of immunological memory. We measured PfEMP1-specific antibody levels by enzyme-linked immunosorbent assay (ELISA) and memory B-cell frequencies by enzyme-linked immunosorbent spot (ELISPOT) assay in a cohort of P. falciparum-exposed nonpregnant Ghanaian women. The antigens used were a VAR2CSA-type PfEMP1 (IT4VAR04) with expression restricted to parasites infecting the placenta, as well as two commonly recognized PfEMP1 proteins (HB3VAR06 and IT4VAR60) implicated in rosetting and not pregnancy restricted. This enabled, for the first time, a direct comparison in the same individuals of immune responses specific for a clinically important parasite antigen expressed only during well-defined periods (pregnancy) to responses specific for comparable antigens expressed independent of pregnancy. Our data indicate that PfEMP1-specific B-cell memory is adequately acquired even when antigen exposure is infrequent (e.g., VAR2CSA-type PfEMP1). Furthermore, immunological memory specific for VAR2CSA-type PfEMP1 can be maintained for many years without antigen reexposure and after circulating antigen-specific IgG has disappeared. The study provides evidence that natural exposure to P. falciparum leads to formation of durable B-cell immunity to clinically important PfEMP1 antigens. This has encouraging implications for current efforts to develop PfEMP1-based vaccines. PMID:24566620

The Effect of Different Adjuvants on Immune Parameters and Protection following Vaccination of Sheep with a Larval-Specific Antigen of the Gastrointestinal Nematode, Haemonchus contortus

PubMed Central

Piedrafita, David; Preston, Sarah; Kemp, Joanna; de Veer, Michael; Sherrard, Jayne; Kraska, Troy; Elhay, Martin; Meeusen, Els

2013-01-01

It has recently been recognised that vaccine adjuvants play a critical role in directing the nature of a vaccine induced effector response. In the present study, several adjuvants were evaluated for their ability to protect sheep after field vaccination with the larval-specific Haemonchus contortus antigen, HcsL3. Using a suboptimal antigen dose, aluminium adjuvant was shown to reduce the cumulative faecal egg counts (cFEC) and worm burden by 23% and 25% respectively, in agreement with a previous study. The addition of Quil A to the aluminium-adjuvanted vaccine brought cFEC back to control levels. Vaccination with the adjuvant DEAE-dextran almost doubled the protection compared to the aluminium-adjuvanted vaccine resulting in 40% and 41% reduction in cFEC and worm counts compared to controls. Examination of skin responses following i.d. injection of exsheathed L3, revealed that cFEC was negatively correlated with wheal size and tissue eosinophils for the DEAE-dextran and aluminium-adjuvanted groups respectively. These studies have for the first time shown the potential of DEAE-dextran adjuvant for helminth vaccines, and discovered significant cellular correlates of vaccine-induced protection. PMID:24205209

Immune Response to Giardia duodenalis

PubMed Central

Faubert, Gaétan

2000-01-01

The intestinal protozoan Giardia duodenalis is a widespread opportunistic parasite of humans and animals. This parasite inhabits the upper part of the small intestine and has a direct life cycle. After ingestion of cysts, which are the infective stage, the trophozoites emerge from the cysts in the duodenum and attach to the small intestinal mucosa of the host. Since the migration of trophozoites from the lumen of the intestine into surrounding tissues is an unusual occurrence, the immune response to Giardia remains localized. The identification of antigens that play a role in acquired immunity has been difficult because of the occurrence of antigenic variation and because, Giardia being an ubiquituous organism, it is possible that the antigenic profiles of isolates from different geographic areas will vary. Innate-immunity mechanisms play a role in the control and/or severity of the infection. Both humoral and cell-mediated immune responses play a role in acquired immunity, but the mechanisms involved are unknown. A variety of serological assays have been used to detect circulating antibodies in serum. Because of the biological characteristics of the parasite and the lack of suitable antigens, the sensitivity of serological assays remains poor. On the other hand, detection of antigens in feces of infected patients has met with success. Commercial kits are available, and they are reported to be more sensitive than microscopic examination for the detection of giardiasis on a single specimen. PMID:10627490

Immunolocalization and immunodetection of the excretory/secretory (ES) antigens of Fasciola gigantica.

PubMed

Khan, M A Hannan; Ullah, Rizwan; Rehman, Abdur; Rehman, Lubna; P A, Ahammed Shareef; Abidi, S M A

2017-01-01

The digenetic trematode Fasciola gigantica is a parasite of great agricultural and economic importance. Along with Fasciola hepatica, F. gigantica incurs huge economic losses to the agricultural sector. Because of unavailability of an effective and commercial vaccine, the earliest diagnosis of the disease is the only way to control the disease. The conventional coprological techniques are able to detect the disease only after the parasites get matured and starts releasing their eggs with the faeces of host, therefore prepatent infection remain undiagnosed. The alternative method is by serological tests that uses circulatory antigens. Despite high sensitivity, their reliability is quite low because of the common antigens shared between different helminth parasites. To overcome this, investigation was shifted to identify the copro-antigens which could be more sensitive and reliable. In the present study, we tried to identify some of the immunodominant proteins from the Excretory Secretory (ES) product of F. gigantica which can be further characterized and used for early detection of infection and also as drug and vaccine candidates. The ES products of F. gigantica were collected and used for raising the polyclonal antibody in rabbit. The polypeptide profile was generated as well as immunogenic polypeptides were identified. The Source of ES antigen was immunolocalized using confocal microscopy and dot blot assay was performed to diagnose field infection. The polypeptide profile of ES products revealed a total of 24 polypeptides out of which 12 immunogenic polypeptides were identified by western blotting. Confocal micrographs showed the immunolocalization of antigens in the intestinal caecae, vitalline glands, gonads as well as in the tegument of the worm. The dot blot assay confirmed the utility of ES products for the detection of field infection. Subsequently, cross reactivity was found negative with Gigantocotyle explanatum; an amphitome parasite of same habitat. However, the cross reactivity with other helminths needs to be worked out.

Immunolocalization and immunodetection of the excretory/secretory (ES) antigens of Fasciola gigantica

PubMed Central

Ullah, Rizwan; Rehman, Abdur; Rehman, Lubna; P. A., Ahammed Shareef; Abidi, S. M. A.

2017-01-01

The digenetic trematode Fasciola gigantica is a parasite of great agricultural and economic importance. Along with Fasciola hepatica, F. gigantica incurs huge economic losses to the agricultural sector. Because of unavailability of an effective and commercial vaccine, the earliest diagnosis of the disease is the only way to control the disease. The conventional coprological techniques are able to detect the disease only after the parasites get matured and starts releasing their eggs with the faeces of host, therefore prepatent infection remain undiagnosed. The alternative method is by serological tests that uses circulatory antigens. Despite high sensitivity, their reliability is quite low because of the common antigens shared between different helminth parasites. To overcome this, investigation was shifted to identify the copro-antigens which could be more sensitive and reliable. In the present study, we tried to identify some of the immunodominant proteins from the Excretory Secretory (ES) product of F. gigantica which can be further characterized and used for early detection of infection and also as drug and vaccine candidates. The ES products of F. gigantica were collected and used for raising the polyclonal antibody in rabbit. The polypeptide profile was generated as well as immunogenic polypeptides were identified. The Source of ES antigen was immunolocalized using confocal microscopy and dot blot assay was performed to diagnose field infection. The polypeptide profile of ES products revealed a total of 24 polypeptides out of which 12 immunogenic polypeptides were identified by western blotting. Confocal micrographs showed the immunolocalization of antigens in the intestinal caecae, vitalline glands, gonads as well as in the tegument of the worm. The dot blot assay confirmed the utility of ES products for the detection of field infection. Subsequently, cross reactivity was found negative with Gigantocotyle explanatum; an amphitome parasite of same habitat. However, the cross reactivity with other helminths needs to be worked out. PMID:28973017

Molecular and antigenic traits on hemagglutinin gene of avian influenza H9N2 viruses: Evidence of a new escape mutant in Egypt adapted in quails.

PubMed

Adel, Amany; Arafa, Abdelsatar; Hussein, Hussein A; El-Sanousi, Ahmed A

2017-06-01

The LPAI viruses of H9N2 subtype became widely distributed in Middle Eastern countries, causing great economic losses in poultry industry especially when complicated with other pathogens. The H9N2 viruses in Egypt have a wide spread nature since its first occurrence in 2011. In this study, we collected cloacal and tracheal samples from 19 flocks for detection and propagation of H9N2 virus using real-time RT-PCR and egg inoculation. We studied the molecular evolution of the Hemagglutinin gene of H9N2 viruses by full HA gene sequencing, then the antigenic characterization was implemented using the cross HI assay and analyzed using 3D Bioinformatics cartography software. The phylogenetic analysis of the HA gene of Egyptian H9N2 viruses clearly points out the presence of only one group (Egy/G1) of originally introduced viruses in 2011 related to the G1 lineage within group B, with the presence of multiple minor clusters includes viruses from 2011 to 2015. However, a new variant (Egy/G1var) cluster was detected in quails since 2012. Genetically, Egy/G1var viruses characterized by presence of 20 amino acid substitutions within and adjacent to the antigenic sites in comparison to other Egyptian viruses. In addition, two glycosylation sites at amino acid residues 127 and 189 were determined in close to the receptor binding and antigenic sites. The antigenic analysis based on 3D antigenic mapping showed that the Egy/G1var cluster was clearly distinct from the original Egy/G1 viruses. In conclusion, Egy/G1var is shown to be a new escape mutant variant cluster with an adaptive evolution in quails. Copyright © 2017 Elsevier Ltd. All rights reserved.

An exploratory study of inflammatory cytokines as prognostic biomarkers in patients with ductal pancreatic adenocarcinoma.

PubMed

Dima, Simona O; Tanase, Cristiana; Albulescu, Radu; Herlea, Vlad; Chivu-Economescu, Mihaela; Purnichescu-Purtan, Raluca; Dumitrascu, Traian; Duda, Dan G; Popescu, Irinel

2012-10-01

We measured the serum concentration of a panel of inflammatory cytokines and evaluated their association with circulating proangiogenic biomarkers and with outcome in patients with pancreatic ductal adenocarcinoma (PDAC). We collected serum samples from 36 patients with PDAC, 9 patients with chronic pancreatitis, and 22 healthy volunteers as a control. Inflammatory cytokines and proangiogenic biomarkers were measured using the multianalyte xMAP array and carcinoembryonic antigen (CEA) and carbohydrate 19-9 by immunoassay. Patients with PDAC had higher circulating levels of interleukin 6 (IL-6) than those of patients with pancreatitis or healthy individuals and higher levels of IL-10 and tumor necrosis factor α (TNF-α) compared with those of healthy individuals. In patients with PDAC, circulating IL-6, TNF-α, IL-1β, and IL-10 correlated with serum concentrations of vascular endothelial growth factor and basic fibroblast growth factor; circulating IL-6, IL-1β, and TNF-α correlated with carbohydrate 19-9; and IL-8, IL-10, and TNF-α correlated with CEA levels. Circulating IL-8, TNF-α, and CEA; tumor stage; and lymph node metastases were associated with a poor outcome. The results of this exploratory study indicate that inflammatory cytokines should be pursued as potential prognostic biomarkers as well as targets for therapy in larger studies in PDAC.

IL-10R Blockade during Chronic Schistosomiasis Mansoni Results in the Loss of B Cells from the Liver and the Development of Severe Pulmonary Disease

PubMed Central

Fairfax, Keke C.; Amiel, Eyal; King, Irah L.; Freitas, Tori C.; Mohrs, Markus; Pearce, Edward J.

2012-01-01

In schistosomiasis patients, parasite eggs trapped in hepatic sinusoids become foci for CD4+ T cell-orchestrated granulomatous cellular infiltrates. Since the immune response is unable to clear the infection, the liver is subjected to ongoing cycles of focal inflammation and healing that lead to vascular obstruction and tissue fibrosis. This is mitigated by regulatory mechanisms that develop over time and which minimize the inflammatory response to newly deposited eggs. Exploring changes in the hepatic inflammatory infiltrate over time in infected mice, we found an accumulation of schistosome egg antigen-specific IgG1-secreting plasma cells during chronic infection. This population was significantly diminished by blockade of the receptor for IL-10, a cytokine implicated in plasma cell development. Strikingly, IL-10R blockade precipitated the development of portal hypertension and the accumulation of parasite eggs in the lungs and heart. This did not reflect more aggressive Th2 cell responsiveness, increased hepatic fibrosis, or the emergence of Th1 or Th17 responses. Rather, a role for antibody in the prevention of severe disease was suggested by the finding that pulmonary involvement was also apparent in mice unable to secrete class switched antibody. A major effect of anti-IL-10R treatment was the loss of a myeloid population that stained positively for surface IgG1, and which exhibited characteristics of regulatory/anti-inflammatory macrophages. This finding suggests that antibody may promote protective effects within the liver through local interactions with macrophages. In summary, our data describe a role for IL-10-dependent B cell responses in the regulation of tissue damage during a chronic helminth infection. PMID:22291593

Antisperm antibodies in prepubertal boys and their reactivity with antigenic determinants on differentiated spermatozoa.

PubMed

Domagała, A; Kamieniczna, M; Kowalczyk, D; Kurpisz, M

1998-09-01

Antisperm antibodies induced in prepubertal boys with testicular failures were characterized by using four techniques of antibody detection. The reactivity of circulating antisperm antibodies in prepubertal boys and the reactivity of antibodies in sera samples of adult fertile and infertile males were compared against the same sperm antigenic pools (live or fixed spermatozoa, or sperm antigenic extracts). The incidence of antisperm antibodies in sera samples of 69 prepubertal boys with testicular failures and 21 samples obtained from adult, male individuals was assessed by indirect immunobead binding test (IDIBT), flow cytometry measurement, enzyme-linked immunosorbent assay, and Western blotting. Immunoblot analysis was performed by using sperm extracts of glycosylated and deglycosylated solubilized membrane antigens. Sera samples were studied in a group composed of healthy prepubertal boys (n = 7) and prepubertal boys with testicular failures (n = 69). Applied tests of antibody detection revealed striking differences in a group of boys with testicular pathology. With IDIBT, 7% of the sera samples were found positive, whereas with flow cytometry measurement, 48% of the sera samples were positive. Immunosorbent assay (fixed sperm) indicated 32% positive cases in the same group. The sera samples were found to be positive in 65% of immunoblotting reactions with glycosylated antigens and in 70% of immunoblotting reactions with deglycosylated antigens. All applied detection assays were clearly negative on sera samples from fertile, adult males. Western immunoblotting indicated an immunodominant antigenic determinant of 58 kDa. Tests of antibody detection with the use of live sperm (IDIBT and flow cytometry measurements) presented low sensitivity (8% and 48%, respectively) in a group of prepubertal boys. This observation underlines the difficulties in assigning the prospective prognosis of future fertility status in prepubertal boys with antisperm antibodies.

Reduced IFN-γ and IL-10 responses to paternal antigens during and after pregnancy in allergic women.

PubMed

Persson, Marie; Ekerfelt, Christina; Ernerudh, Jan; Matthiesen, Leif; Abelius, Martina Sandberg; Jonsson, Yvonne; Berg, Göran; Jenmalm, Maria C

2012-09-01

Normal pregnancy and allergy are both characterized by a T helper (Th) 2 deviation. In the current study, we hypothesized that paternal antigen-induced cytokine responses during pregnancy would be deviated toward Th2 and an anti-inflammatory profile, and that the Th2 deviation would be more pronounced in allergic pregnant women. Blood samples were collected longitudinally on three occasions during pregnancy and two occasions post partum (pp). Of the 86 women initially included, 54 women had a normal pregnancy and completed the sampling procedures. Twelve women fulfilled the criteria for allergy (allergic symptoms and circulating immunoglobulin [Ig] E antibodies to inhalant allergens) and 20 were non-allergic (nonsensitized without symptoms). The levels of Th1- and Th2-associated cytokines and chemokines, the Th17 cytokine IL-17 and the anti-inflammatory cytokine IL-10 of the groups were compared. Paternal antigen-induced IL-4 and IL-10 responses increased between the first and the third trimester. Allergy was associated with decreased paternal antigen-induced IFN-γ and CXCL10 secretion in the nonpregnant state (one year pp) and also decreased IFN-γ/IL-4 and IFN-γ/IL-13 ratios during pregnancy. We also observed a decreased paternal antigen-induced IL-10 response in allergic compared with non-allergic women during pregnancy, along with a decreased IL-10/IL-13 ratio. In conclusion, our findings support the hypothesis of lower Th1 responses toward paternal antigens in allergic than in non-allergic women, but also indicate that allergy is associated with a lower capacity to induce anti-inflammatory IL-10 responses after paternal antigen stimulation during pregnancy. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Antigenic Differences between AS03 Adjuvanted Influenza A (H1N1) Pandemic Vaccines: Implications for Pandemrix-Associated Narcolepsy Risk

PubMed Central

Vaarala, Outi; Vuorela, Arja; Partinen, Markku; Baumann, Marc; Freitag, Tobias L.; Meri, Seppo; Saavalainen, Päivi; Jauhiainen, Matti; Soliymani, Rabah; Kirjavainen, Turkka; Olsen, Päivi; Saarenpää-Heikkilä, Outi; Rouvinen, Juha; Roivainen, Merja; Nohynek, Hanna; Jokinen, Jukka; Julkunen, Ilkka; Kilpi, Terhi

2014-01-01

Background Narcolepsy results from immune-mediated destruction of hypocretin secreting neurons in hypothalamus, however the triggers and disease mechanisms are poorly understood. Vaccine-attributable risk of narcolepsy reported so far with the AS03 adjuvanted H1N1 vaccination Pandemrix has been manifold compared to the AS03 adjuvanted Arepanrix, which contained differently produced H1N1 viral antigen preparation. Hence, antigenic differences and antibody response to these vaccines were investigated. Methods and Findings Increased circulating IgG-antibody levels to Pandemrix H1N1 antigen were found in 47 children with Pandemrix-associated narcolepsy when compared to 57 healthy children vaccinated with Pandemrix. H1N1 antigen of Arepanrix inhibited poorly these antibodies indicating antigenic difference between Arepanrix and Pandemrix. High-resolution gel electrophoresis quantitation and mass spectrometry identification analyses revealed higher amounts of structurally altered viral nucleoprotein (NP) in Pandemrix. Increased antibody levels to hemagglutinin (HA) and NP, particularly to detergent treated NP, was seen in narcolepsy. Higher levels of antibodies to NP were found in children with DQB1*06∶02 risk allele and in DQB1*06∶02 transgenic mice immunized with Pandemrix when compared to controls. Conclusions This work identified 1) higher amounts of structurally altered viral NP in Pandemrix than in Arepanrix, 2) detergent-induced antigenic changes of viral NP, that are recognized by antibodies from children with narcolepsy, and 3) increased antibody response to NP in association of DQB1*06∶02 risk allele of narcolepsy. These findings provide a link between Pandemrix and narcolepsy. Although detailed mechanisms of Pandemrix in narcolepsy remain elusive, our results move the focus from adjuvant(s) onto the H1N1 viral proteins. PMID:25501681

[The phenomenon of antigenic defectiveness in naturally circulating strains of the tick-borne encephalitis virus and its possible connection to seronegative forms of the disease].

PubMed

Pogodina, V V; Bochkova, N G; Dzhivanian, T I; Levina, L S; Karganova, G G; Riasova, R A; Sergeeva, V A; Lashkevich, V A

1992-01-01

Ten strains of tick-borne encephalitis (TBE) virus isolated from single specimens of I. persulcatus ticks were studied. The strains were divided into antigenically complete (AC) and antigenically defective (AD), depending on the presence or absence of some virus antigens in concentrated virus preparations, characteristics in rocket immune electrophoresis (RIEP), rate and intensity of humoral immune response in monkeys and rabbits, and plaque size in SPEV cell culture. The AC-strain markers include high activities of precipitating, hemagglutinating (HA), and complement-fixing (CF) antigens, formation of precipitates moving in rocket shape towards anode and cathode in RIEP, rapid development of antihemagglutinins and virus-neutralizing antibodies, large plaques (3-5 mm). The AD variants are characterized by the lack of HA and precipitating activity, low titres of CF antigen, slow and poor immune response, the lack of cathode precipitate "rocket", very small plaques. The antigenic defectiveness is transitory and shows in early passages; after 10-11 passages in SPEV cell cultures or in white mice, transformation AD----AC occurs. A transformed strain is neutralized, like standard TBE strains, by blood sera of a typical patient with poliomyelitis-like form of TBE. Examinations of blood sera from the population of an endemic zone (Yaroslavl Province) and 67 TBE patients (Kurgan Province) demonstrated the association of AC and AD variants with the formation of immune portion of the population and TBE etiology. Cases of the disease confirmed by seroconversion in HI with commercial diagnosticum are associated with AC variants, whereas AD variants are associated with those TBE cases which are difficult to diagnose using the commercial diagnosticum.

Circulating auto-antibodies against nuclear and non-nuclear antigens in primary Sjögren's syndrome: prevalence and clinical significance in 335 patients.

PubMed

Nardi, Norma; Brito-Zerón, Pilar; Ramos-Casals, Manuel; Aguiló, Sira; Cervera, Ricard; Ingelmo, Miguel; Font, Josep

2006-05-01

The aim of this study was to analyze the prevalence and clinical significance of circulating auto-antibodies against nuclear and non-nuclear antigens in a large cohort of Spanish patients with primary Sjögren's syndrome (SS). We studied 335 patients diagnosed with primary SS seen consecutively in our department since 1994 and tested for anti-nuclear antibodies (ANA), anti-Ro/SS-A, anti-La/SS-B, anti-Sm, anti-ribonucleoprotein (anti-RNP), anti-smooth muscle antibodies (anti-SMA), anti-parietal cell antibodies (anti-PCA), anti-liver-kidney microsome type-1 (anti-LKM-1) antibodies and anti-mitochondrial antibodies (AMA). ANA were detected in 278 (83%) patients. The association of positive ANA with the presence of anti-Ro/SS-A and anti-La/SS-B antibodies reached statistical significance at a titre of ANA >1/80 (p<0.001), while the presence of anti-Sm and anti-RNP was associated with positive ANA at a titre > or =1/320 (p=0.037 for Sm and p=0.016 for RNP). ANA titres correlated with the number of positive antibodies against specific nuclear antigens (p<0.001) but not with the number of positive antibodies against non-nuclear antigens. We found positive anti-Ro/SS-A antibodies in 111 (33%) patients, anti-La/SS-B in 78 (23%), anti-RNP in 8 (2%) and anti-Sm in 4 (1%). Anti-SMA antibodies were detected in 208 (62%) patients, with no significant associations with clinical or analytical SS features, while anti-PCA antibodies were found in 90 (27%) patients and were associated with a higher prevalence of thyroiditis and liver involvement. AMA were detected in 28 (8%) patients, although only 14 presented clinical and/or analytical evidence of liver involvement. No patient presented anti-LKM antibodies. ANA play a central role in the immunological expression of primary SS, due to their frequency and close association with the underlying presence of one or more anti-ENA antibodies. Positivity for antibodies against non-nuclear antigens such as anti-PCA and AMA suggests an association with some organ-specific autoimmune diseases (thyroiditis and primary biliary cirrhosis), while the presence of anti-SMA, in spite of their high prevalence, has no clinical significance in primary SS.

Development of a Novel Method to Detect Prostate Cancer Circulating Tumor Cells (CTCs) Based on Epithelial-Mesenchymal Transition Biology

DTIC Science & Technology

2015-12-01

different incubation periods for the cell lines (1 hour and overnight). We found that room temperature incubation provided the optimal temperature ...properties, either directly (through modification of residues in the complementarity determining region (CDR)) or indirectly through allosteric effects ...showed that the reduction in antigen binding affinity is associated with handling the antibody (e.g. temperature , buffer, purification steps) rather

Emergence of a Norovirus GII.4 Strain Correlates with Changes in Evolving Blockade Epitopes

PubMed Central

Lindesmith, Lisa C.; Costantini, Verónica; Swanstrom, Jesica; Debbink, Kari; Donaldson, Eric F.; Vinjé, Jan

2013-01-01

The major capsid protein of norovirus GII.4 strains is evolving rapidly, resulting in epidemic strains with altered antigenicity. GII.4.2006 Minerva strains circulated at pandemic levels in 2006 and persisted at lower levels until 2009. In 2009, a new GII.4 variant, GII.4.2009 New Orleans, emerged and since then has become the predominant strain circulating in human populations. To determine whether changes in evolving blockade epitopes correlate with the emergence of the GII.4.2009 New Orleans strains, we compared the antibody reactivity of a panel of mouse monoclonal antibodies (MAbs) against GII.4.2006 and GII.4.2009 virus-like particles (VLPs). Both anti-GII.4.2006 and GII.4.2009 MAbs effectively differentiated the two strains by VLP-carbohydrate ligand blockade assay. Most of the GII.4.2006 MAbs preferentially blocked GII.4.2006, while all of the GII.4.2009 MAbs preferentially blocked GII.4.2009, although 8 of 12 tested blockade MAbs blocked both VLPs. Using mutant VLPs designed to alter predicted antigenic epitopes, binding of seven of the blockade MAbs was impacted by alterations in epitope A, identifying residues 294, 296, 297, 298, 368, and 372 as important antigenic sites in these strains. Convalescent-phase serum collected from a GII.4.2009 outbreak confirmed the immunodominance of epitope A, since alterations of epitope A affected serum reactivity by 40%. These data indicate that the GII.4.2009 New Orleans variant has evolved a key blockade epitope, possibly allowing for at least partial escape from protective herd immunity and provide epidemiological support for the utility of monitoring changes in epitope A in emergent strain surveillance. PMID:23269783

Ethnic Variation in Inflammatory Profile in Tuberculosis

PubMed Central

Coussens, Anna K.; Wilkinson, Robert J.; Nikolayevskyy, Vladyslav; Elkington, Paul T.; Hanifa, Yasmeen; Islam, Kamrul; Timms, Peter M.; Bothamley, Graham H.; Claxton, Alleyna P.; Packe, Geoffrey E.; Darmalingam, Mathina; Davidson, Robert N.; Milburn, Heather J.; Baker, Lucy V.; Barker, Richard D.; Drobniewski, Francis A.; Mein, Charles A.; Bhaw-Rosun, Leena; Nuamah, Rosamond A.; Griffiths, Christopher J.; Martineau, Adrian R.

2013-01-01

Distinct phylogenetic lineages of Mycobacterium tuberculosis (MTB) cause disease in patients of particular genetic ancestry, and elicit different patterns of cytokine and chemokine secretion when cultured with human macrophages in vitro. Circulating and antigen-stimulated concentrations of these inflammatory mediators might therefore be expected to vary significantly between tuberculosis patients of different ethnic origin. Studies to characterise such variation, and to determine whether it relates to host or bacillary factors, have not been conducted. We therefore compared circulating and antigen-stimulated concentrations of 43 inflammatory mediators and 14 haematological parameters (inflammatory profile) in 45 pulmonary tuberculosis patients of African ancestry vs. 83 patients of Eurasian ancestry in London, UK, and investigated the influence of bacillary and host genotype on these profiles. Despite having similar demographic and clinical characteristics, patients of differing ancestry exhibited distinct inflammatory profiles at presentation: those of African ancestry had lower neutrophil counts, lower serum concentrations of CCL2, CCL11 and vitamin D binding protein (DBP) but higher serum CCL5 concentrations and higher antigen-stimulated IL-1 receptor antagonist and IL-12 secretion. These differences associated with ethnic variation in host DBP genotype, but not with ethnic variation in MTB strain. Ethnic differences in inflammatory profile became more marked following initiation of antimicrobial therapy, and immunological correlates of speed of elimination of MTB from the sputum differed between patients of African vs. Eurasian ancestry. Our study demonstrates a hitherto unappreciated degree of ethnic heterogeneity in inflammatory profile in tuberculosis patients that associates primarily with ethnic variation in host, rather than bacillary, genotype. Candidate immunodiagnostics and immunological biomarkers of response to antimicrobial therapy should be derived and validated in tuberculosis patients of different ethnic origin. PMID:23853590

Monitoring of circulating antibodies in a renal transplantation population: preliminary results.

PubMed

Rodríguez Ferrero, M L; Arroyo, D; Panizo, N; Vicario, J L; Balas, A; Anaya, F

2012-11-01

The presence of circulating antibodies (CA) against human leukocyte antigen (HLA) and major-histocompatibility-complex class I-related chain A (MICA) antigens has been associated with worse renal function and reduced kidney allograft survival. We sought to describe the presence of donor-specific anti-HLA antibodies, non-donor specific antibodies, and antibodies against MICA antigens among a cohort of renal transplant recipients with respect to their evolution effects on renal function and occurrence of an acute rejection episode (AR) after transplantation. This prospective study of 22 renal transplant recipients of deceased donor kidneys underwent studies of antibodies before and 3 months after grafting using Luminex technology. Ten patients (five men and five women) showed preexistent CA. Comparing patients with versus without preformed CA, we did not observe a significant difference in donor and recipient age or gender. Eight patients (80%) with CA had undergone induction treatment with anti-human-activated T-lymphocyte rabbit immunoglobulin and 2 (20%) with basiliximab. There were no differences between groups regarding the incidence of acute rejection episodes (ARE n = 3 each). There was one case of Banff grade IIB ARE in a patient without preexisting CA; the other episodes were low-grade cellular responses. There were no differences in other variables including cold ischemia time, HLA mismatches, panel-reactive antibody levels, number of transfusions, cytomegalovirus infection or renal function at discharge and 3 months later. Retransplantation was the only factor associated with preformed CA. Retransplantation and preformed CA were associated with CA at 3 months after transplantation. CA monitoring is important for highly sensitized renal transplants, although our experience failed to show a difference in graft survival or renal function in the first 3 months' follow-up. Copyright © 2012 Elsevier Inc. All rights reserved.

Multiple introductions of highly pathogenic avian influenza H5N1 viruses into Bangladesh

PubMed Central

Marinova-Petkova, Atanaska; Feeroz, Mohammed M; Rabiul Alam, SM; Kamrul Hasan, M; Akhtar, Sharmin; Jones-Engel, Lisa; Walker, David; McClenaghan, Laura; Rubrum, Adam; Franks, John; Seiler, Patrick; Jeevan, Trushar; McKenzie, Pamela; Krauss, Scott; Webby, Richard J; Webster, Robert G

2014-01-01

Highly pathogenic H5N1 and low pathogenic H9N2 influenza viruses are endemic to poultry markets in Bangladesh and have cocirculated since 2008. H9N2 influenza viruses circulated constantly in the poultry markets, whereas highly pathogenic H5N1 viruses occurred sporadically, with peaks of activity in cooler months. Thirty highly pathogenic H5N1 influenza viruses isolated from poultry were characterized by antigenic, molecular, and phylogenetic analyses. Highly pathogenic H5N1 influenza viruses from clades 2.2.2 and 2.3.2.1 were isolated from live bird markets only. Phylogenetic analysis of the 30 H5N1 isolates revealed multiple introductions of H5N1 influenza viruses in Bangladesh. There was no reassortment between the local H9N2 influenza viruses and H5N1 genotype, despite their prolonged cocirculation. However, we detected two reassortant H5N1 viruses, carrying the M gene from the Chinese H9N2 lineage, which briefly circulated in the Bangladesh poultry markets and then disappeared. On the other hand, interclade reassortment occurred within H5N1 lineages and played a role in the genesis of the currently dominant H5N1 viruses in Bangladesh. Few ‘human-like' mutations in H5N1 may account for the limited number of human cases. Antigenically, clade 2.3.2.1 H5N1 viruses in Bangladesh have evolved since their introduction and are currently mainly homogenous, and show evidence of recent antigenic drift. Although reassortants containing H9N2 genes were detected in live poultry markets in Bangladesh, these reassortants failed to supplant the dominant H5N1 lineage. PMID:26038508

Comparison of Detection Limits of 4th Generation Combination HIV Antigen/Antibody, p24 Antigen and Viral Load Assays on Diverse HIV Isolates.

PubMed

Stone, Mars; Bainbridge, John; Sanchez, Ana M; Keating, Sheila M; Pappas, Andrea; Rountree, Wes; Todd, Chris; Bakkour, Sonia; Manak, Mark; Peel, Sheila A; Coombs, Robert W; Ramos, Eric M; Shriver, M Kathleen; Contestable, Paul; Nair, Sangeetha Vijaysri; Wilson, David H; Stengelin, Martin; Murphy, Gary; Hewlett, Indira; Denny, Thomas N; Busch, Michael P

2018-05-23

Detection of acute HIV infection is critical for HIV public health and diagnostics. Clinical 4 th generation antigen-antibody (Ag/Ab) combination (combo) and p24 Ag immunoassays have enhanced detection of acute infection compared to Ab alone assays, but require ongoing evaluation with currently circulating diverse subtypes. Genetically and geographically diverse HIV clinical isolates were used to assess clinical HIV diagnostic, blood screening and next generation assays. Blinded 300 member panels of 20 serially diluted well-characterized antibody negative HIV isolates were distributed to manufacturers and end-user labs to assess relative analytic sensitivity of currently approved and pre-approved clinical HIV 4 th generation Ag/Ab combo or p24 Ag alone immunoassays across diverse subtypes. The limits of virus detection (LODs) were estimated for different subtypes relative to confirmed viral loads. Analysis of immunoassay sensitivity was benchmarked against confirmed viral load measurements on the blinded panel. Based on the proportion of positive results on 300 observations all Ag/Ab combo and standard sensitivity p24 Ag assays performed similarly and within half log LODs, illustrating similar breadth of reactivity and diagnostic utility. Ultrasensitive p24 Ag assays achieved dramatically increased sensitivities, while the rapid combo-assays performed poorly. Similar performance of the different commercially available 4 th gen assays on diverse subtypes supports their use in broad geographic settings with locally circulating HIV clades and recombinant strains. Next generation pre-clinical ultrasensitive p24 Ag assays achieved dramatically improved sensitivity, while p24 Ag detection by rapid 4 th gen assays performed poorly. Copyright © 2018 American Society for Microbiology.

Self-reactivities to the non-erythroid alpha spectrin correlate with cerebral malaria in Gabonese children.

PubMed

Guiyedi, Vincent; Chanseaud, Youri; Fesel, Constantin; Snounou, Georges; Rousselle, Jean-Claude; Lim, Pharat; Koko, Jean; Namane, Abdelkader; Cazenave, Pierre-André; Kombila, Maryvonne; Pied, Sylviane

2007-04-25

Hypergammaglobulinemia and polyclonal B-cell activation commonly occur in Plasmodium sp. infections. Some of the antibodies produced recognize self-components and are correlated with disease severity in P. falciparum malaria. However, it is not known whether some self-reactive antibodies produced during P. falciparum infection contribute to the events leading to cerebral malaria (CM). We show here a correlation between self-antibody responses to a human brain protein and high levels of circulating TNF alpha (TNFalpha), with the manifestation of CM in Gabonese children. To study the role of self-reactive antibodies associated to the development of P. falciparum cerebral malaria, we used a combination of quantitative immunoblotting and multivariate analysis to analyse correlation between the reactivity of circulating IgG with a human brain protein extract and TNFalpha concentrations in cohorts of uninfected controls (UI) and P. falciparum-infected Gabonese children developing uncomplicated malaria (UM), severe non-cerebral malaria (SNCM), or CM. The repertoire of brain antigens recognized by plasma IgGs was more diverse in infected than in UI individuals. Anti-brain reactivity was significantly higher in the CM group than in the UM and SNCM groups. IgG self-reactivity to brain antigens was also correlated with plasma IgG levels and age. We found that 90% of CM patients displayed reactivity to a high-molecular mass band containing the spectrin non-erythroid alpha chain. Reactivity with this band was correlated with high TNFalpha concentrations in CM patients. These results strongly suggest that an antibody response to brain antigens induced by P. falciparum infection may be associated with pathogenic mechanisms in patients developing CM.