Sample records for agglutination test antibodies

  1. Development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus.

    PubMed

    Trinh, Dai Quang; Ogawa, Haruko; Bui, Vuong Nghia; Nguyen, Tham Thi Hong; Gronsang, Dulyatad; Baatartsogt, Tugsbaatar; Kizito, Mugimba Kahoza; AboElkhair, Mohammed; Yamaguchi, Shigeo; Nguyen, Viet Khong; Imai, Kunitoshi

    2015-09-01

    A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value=0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. An influenza A virus agglutination test using antibody-like polymers.

    PubMed

    Sukjee, Wannisa; Thitithanyanont, Arunee; Wiboon-Ut, Suwimon; Lieberzeit, Peter A; Paul Gleeson, M; Navakul, Krongkaew; Sangma, Chak

    2017-10-01

    Antibodies are commonly used in diagnostic routines to identify pathogens. The testing protocols are relatively simple, requiring a certain amount of a specific antibody to detect its corresponding pathogen. Antibody functionality can be mimicked by synthesizing molecularly imprinted polymers (MIPs), i.e. polymers that can selectively recognize a given template structure. Thus, MIPs are sometimes termed 'plastic antibody (PA)'. In this study, we have synthesized new granular MIPs using influenza A virus templates by precipitation polymerization. The selective binding of influenza A to the MIP particles was assessed and subsequently contrasted with other viruses. The affinities of influenza A virus towards the MIP was estimated based on an agglutination test by measuring the amount of influenza subtypes absorbed onto the MIPs. The MIPs produced using the H1N1 template showed specific reactivity to H1N1 while those produced using H5N1 and H3N2 templates showed cross-reactivity.

  3. Direct agglutination test for serologic diagnosis of Neospora caninum infection.

    PubMed

    Romand, S; Thulliez, P; Dubey, J P

    1998-01-01

    A direct agglutination test was evaluated for the detection and quantitation of IgG antibodies to Neospora caninum in both experimental and natural infections in various animal species. As compared with results obtained by the indirect fluorescent antibody test, the direct agglutination test appeared reliable for the serologic diagnosis of neosporosis in a variety of animal species. The direct agglutination test should provide easily available and inexpensive tools for serologic testing for antibodies to N. caninum in many host species.

  4. Development and evaluation of a recombinant-glycoprotein-based latex agglutination test for rabies virus antibody assessment.

    PubMed

    Jemima, Ebenezer Angel; Manoharan, Seeralan; Kumanan, Kathaperumal

    2014-08-01

    The measurement of neutralizing antibodies induced by the glycoprotein of rabies virus is indispensable for assessing the level of neutralizing antibodies in animals or humans. A rapid fluorescent focus inhibition test (RFFIT) has been approved by WHO and is the most widely used method to measure the virus-neutralizing antibody content in serum, but a rapid test system would be of great value to screen large numbers of serum samples. To develop and evaluate a latex agglutination test (LAT) for measuring rabies virus antibodies, a recombinant glycoprotein was expressed in an insect cell system and purified, and the protein was coated onto latex beads at concentrations of 0.1, 0.25, 0.5, 0.75, and 1 mg/ml to find out the optimal concentration for coating latex beads. It was found that 0.5 mg/ml of recombinant protein was optimal for coating latex beads, and this concentration was used to sensitize the latex beads for screening of dog serum samples. Grading of LAT results was done with standard reference serum with known antibody titers. A total of 228 serum samples were tested, out of which 145 samples were positive by both RFFIT and LAT, and the specificity was found to be 100 %. In RFFIT, 151 samples were positive, the sensitivity was found to be 96.03 %, and the accuracy/concordance was found to be 97.39 %. A rapid field test-a latex agglutination test (LAT)-was developed and evaluated for rabies virus antibody assessment using recombinant glycoprotein of rabies virus expressed in an insect cell system.

  5. The relationship between fluorescent, agglutinating, and precipitating antibodies to Candida albicans and their immunoglobin classes

    PubMed Central

    Lehner, T.; Buckley, Helen R.; Murray, I. G.

    1972-01-01

    A parallel study of fluorescent, agglutinating, and precipitating antibodies to Candida albicans revealed that precipitating antibodies belong to the IgG class, whereas agglutinating antibodies reside in the IgG, IgM, and IgA classes. The three types as well as the three classes of antibodies were found in Candida endocarditis and mucocutaneous candidiasis. Immuno-absorption studies suggest that the three serological tests estimate antibodies to mannan determinants of Candida albicans. Images PMID:4555044

  6. Evaluation of a monoclonal antibody-based latex agglutination test for diagnosis of cryptococcosis: comparison with two tests using polyclonal antibodies.

    PubMed Central

    Temstet, A; Roux, P; Poirot, J L; Ronin, O; Dromer, F

    1992-01-01

    Cryptococcal antigen detection has become a routine biological test performed for patients with AIDS. The poor prognosis of cryptococcosis explains the need for reliable tests. We evaluated the performances of a newly commercialized agglutination test that uses a monoclonal antibody specific for cryptococcal capsular polysaccharide (Pastorex Cryptococcus; Sanofi-Diagnostics Pasteur, Marnes-la-Coquette, France) and compared them with those of tests that use polyclonal immune sera (Cryptococcal Antigen Latex Agglutination System, Meridian Diagnostics, Inc., Cincinnati, Ohio; and Crypto-LA, International Biological Labs Inc., Cranbury, N.J.). The sensitivities and specificities of the tests were compared by using purified polysaccharides and yeast suspensions. Clinical specimens (131 serum samples, 41 cerebrospinal fluid samples, 34 urine samples, and 19 bronchoalveolar lavage samples) from 87 human immunodeficiency virus-positive subjects with (40 patients) and without (47 patients) culture-proven cryptococcosis were retrospectively tested during a blinded study. The effect of pronase treatment of samples was assessed for Pastorex Cryptococcus and the Cryptococcal Antigen Latex Agglutination System, and the antigen titers were compared. Our results show that (i) during the screening, concordance among the three tests was 97%; (ii) the use of pronase enhanced both the sensitivities and specificities of the Pastorex Cryptococcus test; (iii) titers agreed for 67% of the cerebrospinal fluid samples and 60% of the serum samples; and (iv) cryptococcosis was detected equally well with Pastorex Cryptococcus and with the other tests, whatever the infecting serotype (A, B, or D). The meaning of in vitro sensitivity and the relationship between titers and sensitivity are discussed. The results show that Pastorex Cryptococcus is a rapid and reliable test for the detection of cryptococcal antigen in body fluids and suggest that kits cannot be used interchangeably to monitor

  7. A novel flow cytometry-based assay for the quantification of antibody-dependent pneumococcal agglutination

    PubMed Central

    van der Gaast—de Jongh, Christa E.; Diavatopoulos, Dimitri A.; de Jonge, Marien I.

    2017-01-01

    The respiratory pathogen Streptococcus pneumoniae is a major cause of diseases such as otitis media, pneumonia, sepsis and meningitis. The first step towards infection is colonization of the nasopharynx. Recently, it was shown that agglutinating antibodies play an important role in the prevention of mucosal colonization with S. pneumoniae. Here, we present a novel method to quantify antibody-dependent pneumococcal agglutination in a high-throughput manner using flow cytometry. We found that the concentration of agglutinating antibodies against pneumococcal capsule are directly correlated with changes in the size and complexity of bacterial aggregates, as measured by flow cytometry and confirmed by light microscopy. Using the increase in size, we determined the agglutination index. The cutoff value was set by measuring a series of non-agglutinating antibodies. With this method, we show that not only anti-polysaccharide capsule antibodies are able to induce agglutination but that also anti-PspA protein antibodies have agglutinating capabilities. In conclusion, we have described and validated a novel method to quantify pneumococcal agglutination, which can be used to screen sera from murine or human vaccination studies, in a high-throughput manner. PMID:28288168

  8. Antibody blocks acquisition of bacterial colonization through agglutination

    PubMed Central

    Roche, A. M.; Richard, A. L.; Rahkola, J. T.; Janoff, E. N.; Weiser, J. N.

    2014-01-01

    Invasive infection often begins with asymptomatic colonization of mucosal surfaces. A murine model of bacterial colonization with Streptococcus pneumoniae was used to study the mechanism for mucosal protection by immunoglobulin. In previously colonized immune mice, bacteria were rapidly sequestered within large aggregates in the nasal lumen. To further examine the role of bacterial agglutination in protection by specific antibodies, mice were passively immunized with IgG purified from anti-pneumococcal sera or pneumococcal type-specific monoclonal human IgA (hIgA1 or hIgA2). Systemically-delivered IgG accessed the mucosal surface and blocked acquisition of colonization and transmission between littermates. Optimal protection by IgG was independent of Fc fragment and complement and, therefore, did not involve an opsonophagocytic mechanism. Enzymatic digestion or reduction of IgG prior to administration showed that protection required divalent binding that maintained its agglutinating effect. Divalent hIgA1 is cleaved by the pneumococcal member of a family of bacterial proteases that generate monovalent Fabα fragments. Thus, passive immunization with hIgA1 blocked colonization by an IgA1-protease deficient mutant (agglutinated), but not the protease-producing wild-type parent (not agglutinated), whereas protease-resistant hIgA2 agglutinated and blocked colonization by both. Our findings highlight the importance of agglutinating antibodies in mucosal defense and reveal how successful pathogens evade this effect. PMID:24962092

  9. Development of enhancing agglutination reaction using gold nanoparticle for pre-transfusion testing.

    PubMed

    Choktaweesak, N; Krasathong, P; Ammaranond, P

    2016-10-01

    To explore an alternative way for antibody detection testing, the examination of gold nanoparticle solution for enhancing unexpected antibodies for pre-transfusion testing was investigated. Exposure of foreign antigens on red blood cells from transfusion can trigger the immune system to produce unexpected antibodies. This immunological response may cause the complication to future transfusion. For detection of unexpected antibodies, the antibody screening test is performed approximately 30-60 min. To reduce turnaround time, enhancing reagent, low-ionic strength solution (LISS), is widely used. However, cost of enhancing reagent is an issue which has concerned in resource limited countries. Gold nanoparticle solution can increase red blood cells agglutination reaction. To solve this issue, study of gold nanoparticle solution was investigated. Samples were performed comparing between LISS and gold nanoparticle solution at antiglobulin phase. After reading the agglutination reaction, supernatants were collected and measured at the optical density at 760 nm by spectrophotometer. The optical density in the tube of gold nanoparticle solution was higher than in the tube of 2-5% cell suspension and monoclonal antibody. It has been observed that gold nanoparticle solution enhanced the reaction of agglutination 98% while LISS enhanced the agglutination only 60·8%. Employing a commercially available enhancing reagent, parallel samples confirmed results providing validation of the assay. It approximately costs $1 US dollars compared to $30 for a commercially available reagent. The low cost and yet effective time-consuming test for antibody screening is a practical and viable solution alternative way for performing in antibody screening test in resource limited countries. © 2016 British Blood Transfusion Society.

  10. Comparison of agglutinating and neutralizing antibodies to serovar hardjo in sows immunized with two commercial whole culture polivalent anti-leptospira bacterins

    PubMed Central

    Soto, Francisco Rafael Martins; Pinheiro, Sônia Regina; Morais, Zenaide Maria; Gonçales, Amane Paldês; de Azevedo, Sérgio Santos; Bernardi, Fernanda; Camargo, Sebastião Rodrigues; Vasconcellos, Silvio Arruda

    2008-01-01

    It was performed the comparison of the intensity and duration of agglutinating and neutralizing antibodies to serovar Hardjo in swines vaccinated with two commercial anti-leptospira bacterins. Sows no reactive to 24 Leptospira sp serovars in the microscopic agglutination test (MAT) were divided in three groups: Group A (n=08): received two vaccine A doses with 30 days interval, Group B (n=08) two vaccine B doses with 30 days interval and Group C (n=08): control no vaccinated against leptospirosis.Blood samples were collected each 30 days during six months following the first vaccination. The sera were tested by MAT and growth inhibition test (GIT) to serovar Hardjo in order to evaluate respectively agglutinating and neutralizing antibodies. It was found that neutralizing antibodies persisted for a longer time than the agglutinating ones and that the absence of agglutinating antibodies does not means in the absence of the neutralizing. The peaks of agglutinating antibodies was obtained at least 30 days earlier than that produced by neutralizing. The duration of both kinds of antibodies measured differed between the two bacterines tested. The period for inducing neutralizing antibodies against serovar Hardjo indicated that gilts must be immunized with two doses of whole culture anti-leptospira bacterines applied 30 days each other at least 90 days before the first mating. For the maintenance of hight levels of neutralizing antibodies the revaccinations must be performed every six months after the first vaccination. PMID:24031250

  11. Anejaculation following spinal cord injury does not induce sperm-agglutinating antibodies.

    PubMed

    Dahlberg, A; Hovatta, O

    1989-02-01

    Antisperm antibodies were tested for by the MAR-test and the tray agglutination test in 16 men with spinal cord injury. None of these men could ejaculate without artificial methods. Seven men ejaculated externally by vibrator stimulation or electroejaculation, while seven exhibited retrograde ejaculation; in two cases no semen was obtained. Sperm density in the external ejaculations was high (average = 405 x 10(6)/ml), with 10-45% motility. None of these 16 men had antisperm antibodies. This result indicates that anejaculation and sperm retention in men with spinal cord injury, even of 30 years duration, does not result in antisperm antibody formation.

  12. MEMS reagent and sample handling procedure: Feasibility of viral antibody detection by passive immune agglutination

    NASA Technical Reports Server (NTRS)

    Bailey, G. D.; Tenoso, H. J.

    1975-01-01

    An attempt was made to develop a test requiring no preadsorption steps for the assessment of antibodies to rubella and mumps viruses using the passive immune agglutination (PIA) method. Both rubella and mumps antigens and antibodies were prepared. Direct PIA tests, using rubella antigen-coated beads, and indirect PIA tests, using rubella antibody-coated beads, were investigated. Attempts, using either method, were unsuccessful. Serum interference along with nonspecific agglutination of beads by the rubella antigen resulted in no specific response under the test conditions investigated. A new, highly sensitive approach, the enzyme immunoassay (EIA) test system, is recommended to overcome the nonspecificity. This system is a logical outgrowth of some of the solid phase work done on MEMS and represents the next generation tests system that can be directly applied to early disease detection and monitoring.

  13. A comparison of sperm agglutination and immobilization assays with a quantitative ELISA for anti-sperm antibody in serum.

    PubMed

    Lynch, D M; Leali, B A; Howe, S E

    1986-08-01

    An enzyme-linked immunosorbent assay (ELISA) that quantitates antisperm antibody in serum was compared with standard sperm agglutination and immobilization assays with the use of sera from 40 normal and 292 subfertile individuals. Quantitation of the assay was accomplished by standardizing assay parameters, including the incorporation of a standard reference curve, the number of whole target sperm, the optimal dilution of serum, the selection of microtiter plate, and the time and temperatures involved in the adsorption and incubation phases. With this method, the level of antisperm antibody binding to target sperm in 40 normal fertile individuals was found to be 2.3 (+/- 1.1 standard deviation [SD]) fg immunoglobulin (Ig)/sperm. An increased mean level of 7.4 +/- 3.7 fg Ig/sperm was determined in 84 infertile patients with positive agglutination and/or immobilization tests. In 208 individuals with negative agglutination and immobilization tests the mean concentration of antisperm antibody was 2.5 +/- 1.3 fg Ig/sperm. Postvasectomy patients assayed by this method had a mean Ig binding value of 7.1 +/- 2.4 fg Ig/sperm. The infertile group with positive agglutination and/or immobilization tests had a significantly higher mean antisperm antibody level than the normal fertile group, according to the Student's t-test for independent samples (P less than 0.001). This indirect serum-based assay reproducibly quantitates antisperm antibody binding to whole target sperm, suggests the normal and abnormal levels of antisperm antibody, and correlates with standard functional assays.

  14. Mechanisms of red blood cells agglutination in antibody-treated paper.

    PubMed

    Jarujamrus, Purim; Tian, Junfei; Li, Xu; Siripinyanond, Atitaya; Shiowatana, Juwadee; Shen, Wei

    2012-05-07

    Recent reports on using bio-active paper and bio-active thread to determine human blood type have shown a tremendous potential of using these low-cost materials to build bio-sensors for blood diagnosis. In this work we focus on understanding the mechanisms of red blood cell agglutination in the antibody-loaded paper. We semi-quantitatively evaluate the percentage of antibody molecules that are adsorbed on cellulose fibres and can potentially immobilize red blood cells on the fibre surface, and the percentage of the molecules that can desorb from the cellulose fibre surface into the blood sample and cause haemagglutination reaction in the bulk of a blood sample. Our results show that 34 to 42% of antibody molecules in the papers treated with commercial blood grouping antibodies can desorb from the fibre surface. When specific antibody molecules are released into the blood sample via desorption, haemagglutination reaction occurs in the blood sample. The reaction bridges the red cells in the blood sample bulk to the layer of red cells immobilized on the fibre surface by the adsorbed antibody molecules. The desorbed antibody also causes agglutinated lumps of red blood cells to form. These lumps cannot pass through the pores of the filter paper. The immobilization and filtration of agglutinated red cells give reproducible identification of positive haemagglutination reaction. Results from this study provide information for designing new bio-active paper-based devices for human blood typing with improved sensitivity and specificity.

  15. Tube and column agglutination technology for autocontrol testing.

    PubMed

    Courtney, J E; Vincent, J L; Indrikovs, A J

    2001-01-01

    The incidence of positive autocontrol test results with column agglutination technology is a concern. This study investigates the incidence and significance of positive autocontrols in the ID Micro Typing System (gel) and the Gamma ReACT (ReACT). The study encompassed a total of 1021 randomly selected samples from patients and 95 samples from donors collected during 1 month. The autocontrol testing was carried out according to the manufacturer's instructions for the column agglutination tests. The tube method was carried out using low-ionic-strength solution (LISS). The direct antiglobulin test (DAT) was performed using the tube method, and further investigated with elution studies if warranted. Seventy-nine patient's samples (7.74%) had a positive autocontrol: the gel test, 72 (91.13%); ReACT, 21 (26.58%); and the tube method, 27 (34.18%). Of the 79 positive autocontrols, 44 samples had a negative DAT. Of the samples with positive DAT results, only one possessed a clinically significant antibody, anti-D. Moreover, the same sample also tested positive in all three methods. Column agglutination techniques have increased sensitivity for a positive autocontrol beyond the conventional tube method. However, ReACT and gel tests differ significantly in their frequency of positives. Investigation of the significance of a positive autocontrol in column agglutination technology when the conventional tube method is also positive is suggested.

  16. The incomplete anti-Rh antibody agglutination mechanism of trypsinized ORh+ red cells.

    PubMed Central

    Margni, R A; Leoni, J; Bazzurro, M

    1977-01-01

    The capacity for binding to trypsinized and non-trypsinized ORh+ red cells, of the IgG incomplete anti-Rh antibody and its F(ab')2 and Fc fragments has been investigated. An analysis has also been made of the capacity of non-specific human IgG, aggregated non-specific human IgG, human IgM (19S) and IgM (7S), and of fragments Fcgamma, Fcmu and Fc5mu to inhibit the agglutination of trypsinized ORh+ red cells by the IgG incomplete anti-Rh antibody. The results obtained indicate that these antibodies behave in a similar manner to that of nonprecipitating antibodies, and that the agglutination of trypsinized red cells seems to be a mixed reaction due to the interaction of an Fab fragment with its Rh antigenic determinant present in the surface of a red cell and the Fc of the same molecule with a receptor for Fc present in adjacent red cells. The trypsin treatment apparently results in the liberation of occult Fc receptors. It has also been demonstrated that in the agglutination of ORh+ red cells by IgG incomplete anti-Rh antibody in the presence of albumin, interaction must occur in some manner between the albumin and the Fc fragment since the F(ab')2 fragment does not give rise to agglutination under such conditions. Images Figure 1 PMID:415968

  17. The utility of direct agglutination (DAT) and fast agglutination screening (FAST) tests in serodiagnosis of experimental microsporidiosis.

    PubMed

    Abou El Naga, Iman F; Gaafar, Maha R; El-Zawawy, Lobna A; El-Said, Doaa; Mossallam, Sherin F

    2008-12-01

    The present study was designed to evaluate the efficiency of two serodiagnostic tests; the direct agglutination test (DAT) and the fast agglutination screening test (FAST) in the diagnosis of Microsporidia in experimentally infected mice and to differentiate between different species of the parasite. The swiss albino mice were divided into non infected control and infected experimental groups which were further subdivided into ten subgroups. Ten samples of microsporidial spores were isolated from ten human stools and each one was used to infect each subgroup of mice. Stool and sera were collected weekly from each subgroup from the 1st to the 4th week post infection (PI). DAT & FAST tests, using antigen prepared from the different species of microsporidial spores were used to detect antibodies in sera of different mice subgroups. The cross reactivity of microsporidial spores with the antibodies of Cyclospora cyatenensis and Cryptosporidium parvum was investigated by DAT & FAST. The results proved that DAT & FAST were effective in detecting microsporidial antibodies in sera of experimentally infected mice from the 2nd week PI till the end of the study, without cross reactivity with C. cyatenensis or C. parvum. They failed to differentiate between different Microspoiridia species used but, they gave good interpretation and they were specific and sensitive, and did not need sophisticated equipments.

  18. [Diagnosis of human brucellosis. Role of pH in the seroagglutination test and influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies].

    PubMed

    Rubio Vallejo, Manuel; del Pozo, José L; Del Pozo León, José Luis; Hernández-Molina, Juan Manuel; Dorronsoro Ibero, Inés; Marrodán Ciordia, Teresa; Díaz García, Ramón

    2002-04-01

    To evaluate the role of pH in the seroagglutination test (SAT)and Rose Bengal (RB) test, and to determine the influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies. The SAT was performed at pH 7.2 or pH 5.0 in standard microtiter-type polystyrene plates using Ring Test antigen or the Brucella suspension (BRUCAPT) provided in the Brucellacapt kits. Specific antibodies against native hapten were determined by radial immunodiffusion. Additionally, IgG, IgA and IgM fractions were separated from 8 sera by absorption chromatography and their agglutinating capacity was studied at pH 7.2 and 5.0. We studied 72 sera from patients with clinical brucellosis taken at the time of hospitalization, 16 from persons in contact with infected animals, and 16 from healthy donors. SAT results at pH 5.0 correlated with those obtained with the Rose Bengal test. Four Rose Bengal-positive sera were found to be SAT-negative at pH 7.2 and SAT-positive at pH 5.0. SAT performed at pH 5.0 with BRUCAPT antigen yielded higher titers than tests performed at pH 7.2 or 5.0 with Ring Test antigen (p < 0.001), with highest titers in IDR-positive sera. Among the 8 IgG fractions, all but one agglutinated at pH 7.2, and in 4, IgG titers showed significant increases at pH 5.0. Three IgA fractions were SAT-negative at pH 7.2 and SAT-positive at pH 5.0; the other 5 agglutinated at both pH conditions and were DTT-sensitive. All IgA fractions but one were positive by Rose Bengal. Agglutinating activity of the IgM fraction was not affected by pH. The SAT performed with the buffer and antigen suspension included in the Brucellacapt kit (pH 5.0) is highly useful for detecting agglutinating and non-agglutinating antibodies at pH 7.2.

  19. Antibodies to Coprococcus comes in sera of patients with Crohn's disease. Isolation and purification of the agglutinating antigen tested with an ELISA technique.

    PubMed

    Hazenberg, M P; van de Merwe, J P; Peña, A S; Pennock-Schröder, A M; van Lieshout, L M

    1987-07-01

    Previous studies showed that agglutinating antibodies to Coprococcus comes, an anaerobic Gram-positive coccoid rod isolated from the faecal flora of patients with Crohn's disease, are more frequently found in sera of Crohn patients than in ulcerative colitis patients and healthy subjects. Isolation of the antigen may be useful in developing a more sensitive and specific diagnostic test. The present study describes first a method to improve the presentation of the relevant agglutinating antigen by the bacterium and second, the purification by column chromatography of a relatively crude antigen extract of C. comes described previously by Hazenberg et al. (1). Comparative results with the agglutination reactions and ELISA technique of extensive series of patients with Crohn's disease and healthy subjects have shown that the agglutinating antigen of C. comes has been isolated. Although the present ELISA technique cannot replace the simple and reliable agglutination reaction for screening purposes, the purified antigen will allow further immunological studies and it is to be hoped that a deeper insight into pathogenesis of the disease will be gained.

  20. Agglutination by anti-capsular polysaccharide antibody is associated with protection against experimental human pneumococcal carriage

    PubMed Central

    Reiné, J; Zangari, T; Owugha, JT; Pennington, SH; Gritzfeld, JF; Wright, AD; Collins, AM; van Selm, S; de Jonge, MI; Gordon, SB; Weiser, JN; Ferreira, DM

    2016-01-01

    The ability of pneumococcal conjugate vaccine (PCV) to decrease transmission by blocking the acquisition of colonization has been attributed to herd immunity. We describe the role of mucosal IgG to capsular polysaccharide (CPS) in mediating protection from carriage, translating our findings from a murine model to humans. We used a flow-cytometric assay to quantify antibody-mediated agglutination demonstrating that hyperimmune sera generated against an unencapsulated mutant was poorly agglutinating. Passive immunization with this antiserum was ineffective to block acquisition of colonization compared to agglutinating antisera raised against the encapsulated parent strain. In the human challenge model samples were collected from PCV and control vaccinated adults. In PCV-vaccinated subjects IgG levels to CPS were increased in serum and nasal wash (NW). IgG to the inoculated strain CPS dropped in NW samples after inoculation suggesting its sequestration by colonizing pneumococci. In post-vaccination NW samples pneumococci were heavily agglutinated compared to pre-vaccination samples in subjects protected against carriage. Our results indicate that pneumococcal agglutination mediated by CPS specific antibodies is a key mechanism of protection against acquisition of carriage. Capsule may be the only vaccine target that can elicit strong agglutinating antibody responses, leading to protection against carriage acquisition and generation of herd immunity. PMID:27579859

  1. Seroprevalence of Mycoplasma gallisepticum antibody by ELISA and serum plate agglutination test of laying chicken

    PubMed Central

    Ali, Md. Zulfekar; Rahman, Md. Mostafizer; Sultana, Shirin

    2015-01-01

    Aim: Mycoplasma gallisepticum (MG) is important avian pathogens responsible for chronic respiratory diseases of chicken and turkeys, which result in large economic loss for the poultry industry. The objectives of this study were determination of seroprevalence of MG antibody of commercial layer chicken at laying period in selected areas of Bangladesh. Materials and Methods: A total of 563 blood samples were collected randomly from selected commercial layer chickens at laying period during the period from July to December, 2013. Indirect enzyme linked immunosorbent assay (iELISA) and serum plate agglutination (SPA) test were performed to detect the presence of antibodies against MG. Results: Of 563 samples, 64.47% and 56.13% showed an overall prevalence of MG antibodies in iELISA and SPA test respectively. Prevalence of MG was recorded the highest (69.63%) at 50-55 weeks of age compared with lowest (53.26%) at 56-61 weeks of age (p<0.05). Significant (p<0.05) effect of breed were observed in the seroprevalence of MG infection in layer birds in the present study. The overall, 68.77%, 63.74% and 59.37% prevalence were found respectively in sonali, ISA Brown and White leg horn. The prevalence of MG antibodies was the highest (70.13%) in December followed by November (68%), October (65.67%), August (63.46%), September (58.54%) and July (51.78%) month. The seroprevalence of MG antibodies was higher (69.63%) in most of the large flocks and lower (56.82%) in small flocks. Conclusion: Therefore, might be suggested that the commercial layer farms should be routinely checked to monitor MG infection and the reactor birds should be culled since MG organism has the potential to transmit vertically. The correlation between MG antibody in month and flock size was not significant (p=0.359 and p=0.868, respectively). PMID:27046987

  2. Passive immunization with Leptospira LPS-specific agglutinating but not non-agglutinating monoclonal antibodies protect guinea pigs from fatal pulmonary hemorrhages induced by serovar Copenhageni challenge.

    PubMed

    Challa, Sreerupa; Nally, Jarlath E; Jones, Carroll; Sheoran, Abhineet S

    2011-06-15

    Leptospira interrogans serovar Copenhageni causes pulmonary hemorrhages with respiratory failure, a major cause of death in leptospirosis patients. Protective immunity to Leptospira is known to correlate with the production of leptospiral lipopolysaccharide (L-LPS)-specific agglutinating antibodies. We generated L-LPS-specific mouse monoclonal antibodies (MAbs) and investigated if these MAbs can protect guinea pigs against fatal pulmonary hemorrhages caused by serovar Copenhageni. The MAbs L8H4 and L9B11 against 22kDa L-LPS agglutinated leptospires and completely protected guinea pigs from the development of fatal pulmonary hemorrhages by serovar Copenhageni, whereas the MAb L4C1 against 8kDa L-LPS neither agglutinated the bacteria nor protected the animals against the fatal pulmonary hemorrhages. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. [EIA-IgG antibody measles prevention level estimated from measles neutralizing, particle agglutination and hemagglutination-inhibition antibody titer].

    PubMed

    Takayama, Naohide; Saika, Shizuko; Ichinohe, Sadato

    2009-09-01

    Measles hemagglutination inhibition (HI) antibody titer, widely used in clinical practice to simply and easily determine the measles immunity level has, in recent years, been increasingly replaced by measles IgG-antibody titer determined by enzyme-immunoassay (EIA). HI antibody titer appears to reflect this protective level, because HI measures the antibody against H protein required for the measles virus to adhere to host cells. EIA-IgG antibody titer does not correlate with the protective level, similar to particle agglutination (PA) titer, because EIA measures different antibodies, including those unrelated to measles protection. After determining HI, PA, neutralizing test (NT) results, and EIA-IgG antibody titer for individual specimens, we compared EIA-IgG antibody titer obtained using an EIA-Kit (Denka Seiken) to HI, PA, and NT titer with the following results: (1) Subjects with EIA-IgG titer of > or = 12.0 may be protected against measles: (2) Subjects with EIA-IgG titer of 4.0 to 8.0 appear to be protected insufficiently requiring a booster dose against measles: (3) Subjects with EIA-IgG titer of 8.0 to 12.0 may benefit from booster vaccination.

  4. 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).

  5. Prevalence of agglutinating antibodies to Sarcocystis neurona in skunks (Mephitis Mephitis), raccoons (Procyon lotor), and opossums (Didelphis Virginiana) from Connecticut.

    PubMed

    Mitchell, Sheila M; Richardson, Dennis J; Cheadle, M Andy; Zajac, Anne M; Lindsay, David S

    2002-10-01

    Equine protozoal myeloencephalitis is the most important protozoan disease of horses in North America and is usually caused by Sarcocystis neurona. Natural cases of encephalitis caused by S. neurona have been reported in skunks (Mephitis mephitis) and raccoons (Procyon lotor). Opossums (Didelphis spp.) are the only known definitive host. Sera from 24 striped skunks, 12 raccoons, and 7 opossums (D. virginiana) from Connecticut were examined for agglutinating antibodies to S. neurona using the S. neurona agglutination test (SAT) employing formalin-fixed merozoites as antigen. The SAT was validated for skunk sera using pre- and postinfection serum samples from 2 experimentally infected skunks. Of the 24 (46%) skunks 11 were positive, and all 12 raccoons were positive for S. neurona antibodies. None of the 7 opossums was positive for antibodies to S. neurona. These results suggest that exposure to sporocysts of S. neurona by intermediate hosts is high in Connecticut. The absence of antibodies in opossums collected from the same areas is most likely because of the absence of systemic infection in the definitive host.

  6. Determination of immune status in dogs against CPV-2 by recombinant protein based latex agglutination test.

    PubMed

    Thomas, Jobin; Singh, Mithilesh; Goswami, T K; Glora, Philma; Chakravarti, Soumendu; Chander, Vishal; Upmanyu, Vikramaditya; Verma, Suman; Sharma, Chhavi; Mahendran, K

    2017-09-01

    Canine parvoviral enteritis is a highly contagious viral illness caused by canine parvovirus-2 (CPV-2) which affects puppies of mainly 6-20 weeks of age. Vaccination is pivotal in preventing and controlling CPV-2 infection. Determination of antibody status is a critical determinant for successful vaccination. The hemagglutination inhibition (HI) test is 'gold standard' test for quantification of antibodies specific to CPV-2, although the execution of this test is not feasible under field conditions. The present study was undertaken to develop a point of care testing to determine immune status prior to CPV-2 vaccination or to detect seroconversion in immunized dogs by latex agglutination test (LAT) using recombinant antigen. Truncated portion of VP2 protein (tVP2) of CPV-2 was selected on the basis of antigenic indices, overexpressed the recombinant protein in E. coli system and was subsequently used in development of LAT. A total of 59 serum samples obtained from vaccinated (n = 54) and healthy unvaccinated (n = 5) dogs were tested. The positivity was observed in 85% (46/54) of these dogs with varying agglutination pattern. The overall sensitivity and specificity of latex agglutination test in comparison to HI test was recorded as 90% and 88% respectively with an agreement value of 90% (CI = 95%). Copyright © 2017 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  7. Latex agglutination test (LAT) for the diagnosis of typhoid fever.

    PubMed

    Sahni, Gopal Shankar

    2013-06-01

    The efficacy of latex agglutination test in the rapid diagnosis of typhoid fever was studied and the result compared with that of blood culture. This study included 80 children suffering from typhoid fever, among which 40 were confirmed by blood culture isolation and 40 had possible typhoid fever based on high Widal's titre (a four-fold rise in the titre of antibody to typhi "O" and "H" antigen was considered as a positive Widal's test result). Eighty children, 40 with febrile illness confirmed to be other than typhoid and 40 normal healthy children were used as negative controls. The various groups were: (i) Study group ie, group I had 40 children confirmed by culture isolation of Salmonella typhi(confirmed typhoid cases). (ii) Control groups ie, (a) group II with 40 febrile controls selected from paediatrics ward where cause other than S typhi has been established, (b) group III with 40 afebrile healthy controls that were siblings of the children admitted in paediatric ward for any reason with no history of fever and TAB vaccination in the last one year, and (c) group IV with 40 children with high Widal's titre in paired sera sample. Widal's test with paired sera with a one week interval between collections were done in all 40 patients. Latex aggtutination test which could detect 900 ng/ml of antigen as observed in checker board titration, was positive in all 40 children from group I who had positive blood culture and in 30 children from group IV who had culture negative and had high Widal's titre positive. Latex agglutination test was positive in 4 children in group II and none in group III. Using blood culture positive cases as true positive and children in groups II and III as true negative, the test had a sensitivity of 100% and specificity of 96%. Latex agglutination test was found to be significantly sensitive (100%) and specific (96%) and could detect 75% more cases in group IV (possible typhoid cases). Thus latex agglutination test can be used for rapid

  8. The specificity of the cross-reacting antibodies in blood group O sera which produce mixed agglutination

    PubMed Central

    Franks, D.; Liske, Rosemary

    1968-01-01

    γM cross-reacting antibodies in group O sera produce mixed agglutination with secretor buccal cells, but not with non-secretor cells. The mixed agglutination with sera which also contain immune anti-B is produced only with A buccal cells and B indicator red cells, and not with B buccal cells, and is inhibited by B secretor saliva or galactose, but not by A secretor saliva. Mixed agglutination with sera containing immune anti-A is produced only with B buccal cells and A indicator red cells, and is inhibited by A secretor saliva or 2-acetamido-2-deoxygalactose (N-acetyl-D-galactosamine), but not by B secretor saliva. If two sera, one containing immune anti-A and the other containing immune anti-B, are mixed together in equal volumes, mixed agglutination is no longer produced with either A buccal cells (and B indicator red cells) or B buccal cells (and A indicator red cells). These observations are thought to be most readily explicable by the hypothesis that the combining site on the cross-reacting antibody is smaller than on specific anti-A or anti-B, and that it reacts with that part of the antigenic determinant which is common to both A and B antigens. As a consequence of the restricted size of the combining site, it is suggested that cross-reacting antibody will have a lower affinity for A or B antigens than specific anti-A or anti-B does, and competes unsuccessfully with specific anti-A or anti-B for combination with antigen on buccal cells. PMID:5638582

  9. Naturally occurring pepsin agglutinators in the serum of subhuman primates*

    PubMed Central

    Litwin, S. D.

    1970-01-01

    Antibodies directed against both human and infrahuman pepsin digested γ-globulin were present in a majority of the primate sera tested. The subhuman pepsin agglutinators paralleled previously described human pepsin agglutinators in respect to their wide distribution in normal sera, their specificity and cross-reactivity, and their immunochemical features. The pepsin agglutinators† at different primate levels appeared closely related. Among the subhuman pepsin agglutinators a subspecificity was described for a subhuman primate antigen. This finding suggested some limited differences between the subhuman pepsin agglutinators and the human pepsin agglutinators. Experimental immunization of four cynomologous monkeys failed to elicit or alter these serum reactants. PMID:4097824

  10. Standardization of a latex agglutination test for coproantigen detection of Fasciola sp. in bovine cattle stool.

    PubMed

    Orejarena Ávila, Lina Paola; Inguilan Benavides, Erika Marcela; Padilla Sanabria, Leonardo; Recalde-Reyes, Delia Piedad; Rodríguez-Salazar, Carlos Andrés; Castaño-Osorio, Jhon Carlos

    2018-03-01

    Fasciolosis is a zoonotic parasitic disease, which affects humans and animals; diagnosed through noncommercial immunoassay tests that cannot be used on the field. Thereby, establishing the optimal conditions to develop a latex agglutination technique with IgG and IgM antibodies directed against excretion/secretion antigens of Fasciola sp. is a priority. Latex particles were sensitized with IgG and IgM antibodies directed against excretion/secretion antigens of Fasciola sp. The specificity of the antibodies was determined against antigens of different helminths and protozoa; the sensitivity and specificity of the test was evaluated against a previously standardized direct ELISA. The coupling rates of the IgG and IgM antibodies were 85.77 and 100%, respectively. The minimum detectable concentration of Fasciola sp. excretion/secretion antigens, diluted in a phosphate-buffered saline, was 1.589 mg/mL(IgG) and 0.158 mg/mL(IgM) and for the antigens incorporated in the bovine cattle stool it was 3.178 mg/mL(IgG) and 1.589 mg/mL(IgM). The test showed crossed reaction against Giardia sp., and Cryptosporidium sp. antigens. Agreement of the IgG and IgM latex test against the ELISA test was of 78.78 and 96.96%, respectively; the specificity found was of 100% for both tests and sensitivity was 78.79% (IgG) and 96.97% (IgM). This work standardized the latex agglutination technique to detect Fasciola sp. antigens in bovine cattle stool.

  11. A critical review of published methods for analysis of red cell antigen-antibody reactions by flow cytometry, and approaches for resolving problems with red cell agglutination.

    PubMed

    Arndt, Patricia A; Garratty, George

    2010-07-01

    Flow cytometry operators often apply familiar white blood cell (WBC) methods when studying red blood cell (RBC) antigens and antibodies. Some WBC methods are not appropriate for RBCs, as the analysis of RBCs requires special considerations, for example, avoidance of agglutination. One hundred seventy-six published articles from 88 groups studying RBC interactions were reviewed. Three fourths of groups used at least one unnecessary WBC procedure for RBCs, and about one fourth did not use any method to prevent/disperse RBC agglutination. Flow cytometric studies were performed to determine the effect of RBC agglutination on results and compare different methods of preventing and/or dispersing agglutination. The presence of RBC agglutinates have been shown to be affected by the type of pipette tip used for mixing RBC suspensions, the number of antigen sites/RBC, the type and concentration of primary antibody, and the type of secondary antibody. For quantitation methods, for example, fetal maternal hemorrhage, the presence of agglutinates have been shown to adversely affect results (fewer fetal D+ RBCs detected). Copyright 2010 Elsevier Inc. All rights reserved.

  12. Serotyping of Actinobacillus pleuropneumoniae serotype 5 strains using a monoclonal-based polystyrene agglutination test.

    PubMed Central

    Dubreuil, J D; Letellier, A; Stenbaek, E; Gottschalk, M

    1996-01-01

    A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS-PAGE and Western blotting. A total of 205 A. pleuropneumoniae, strains including all 12 serotype reference strains and 13 strains representing 8 common bacterial species associated with swine or related to A. pleuropneumoniae, were tested by mixing 25 microL of polystyrene reagent with the same volume of a dense suspension of bacterial cells grown for 18 h. All A. pleuropneumoniae strains had been previously serotyped using standard procedures. The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found. The sensitized polystyrene particles were stable for at least 6 mo. Images Figure 1. PMID:8825998

  13. Agglutination Assays of the Plasmodium falciparum-Infected Erythrocyte.

    PubMed

    Tan, Joshua; Bull, Peter C

    2015-01-01

    The agglutination assay is used to determine the ability of antibodies to recognize parasite variant antigens on the surface of Plasmodium falciparum-infected erythrocytes. In this technique, infected erythrocytes are selectively labelled with a DNA-binding fluorescent dye and mixed with antibodies of interest to allow antibody-surface antigen binding. Recognition of surface antigens by the antibodies can result in the formation of agglutinates containing multiple parasite-infected erythrocytes. These can be viewed and quantified using a fluorescence microscope.

  14. Minimization of bacterial size allows for complement evasion and is overcome by the agglutinating effect of antibody

    PubMed Central

    Dalia, Ankur B.; Weiser, Jeffrey N.

    2011-01-01

    SUMMARY The complement system, which functions by lysing pathogens directly or by promoting their uptake by phagocytes, is critical for controlling many microbial infections. Here we show that in Streptococcus pneumoniae, increasing bacterial chain length sensitizes this pathogen to complement deposition and subsequent uptake by human neutrophils. Consistent with this, we show that minimizing chain length provides wild-type bacteria with a competitive advantage in vivo in a model of systemic infection. Investigating how the host overcomes this virulence strategy, we find that antibody promotes complement-dependent opsonophagocytic killing of Streptococcus pneumoniae and lysis of Haemophilus influenzae independent of Fc-mediated effector functions. Consistent with the agglutinating effect of antibody, F(ab′)2 but not Fab could promote this effect. Therefore, increasing pathogen size, whether by natural changes in cellular morphology or via antibody-mediated agglutination, promotes complement-dependent killing. These observations have broad implications for how cell size and morphology can affect virulence among pathogenic microbes. PMID:22100164

  15. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

  16. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

  17. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

  18. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

  19. 9 CFR 147.1 - The standard tube agglutination test. 1

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

  20. Serodiagnosis of bovine leptospirosis by IgG-enzyme-linked immunosorbent assay and latex agglutination test.

    PubMed

    Senthilkumar, T M A; Subathra, M; Ramadass, P; Ramaswamy, V

    2010-02-01

    The efficacy of a recombinant leptospiral outer membrane protein LipL41 as an antigen for conducting IgG-Enzyme linked immunosorbent assay (ELISA) and latex agglutination test (LAT) for serodiagnosis of bovine leptospirosis was evaluated. The recombinant LipL41 antigen developed and used for detecting the antibodies was specific in detection of the pathogenic serovars of Leptospira, as the expression of the LipL41 antigen is restricted only to pathogenic leptospires. A total of 430 bovine serum samples were subjected to IgG-ELISA and LAT, and the sensitivity and specificity were assessed in comparison with microscopic agglutination test (MAT). The sensitivity and specificity of IgG-ELISA and LAT were 86.84% and 93.16%, and 95.42% and 98.33% respectively. Both the tests are found to be sensitive, specific and concurred with the standard MAT. The study concluded that the rLipL41 protein could be used as a potential diagnostic antigen in different assay formats for bovine leptospirosis.

  1. Evaluation of Two rK39 Dipstick Tests, Direct Agglutination Test, and Indirect Fluorescent Antibody Test for Diagnosis of Visceral Leishmaniasis in a New Epidemic Site in Highland Ethiopia

    PubMed Central

    Cañavate, Carmen; Herrero, Merce; Nieto, Javier; Cruz, Israel; Chicharro, Carmen; Aparicio, Pilar; Mulugeta, Abate; Argaw, Daniel; Blackstock, Anna J.; Alvar, Jorge; Bern, Caryn

    2011-01-01

    We assessed the performance characteristics of two rK39 immunochromatographic tests, a direct agglutination test (DAT), and an indirect immunofluorescent antibody test (IFAT) in the site of a new epidemic of visceral leishmaniasis (VL) in northwestern Ethiopia. The study population was composed of 179 patients with suspected VL and 67 controls. The sensitivities of Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT in 35 polymerase chain reaction–confirmed VL cases were 94.3%, 91.4%, 91.4%, and 100%, respectively, and the specificities were 98.5%, 94%, 98.5%, and 98.5%, respectively. In a Bayesian latent class analysis of all 246 specimens, the estimated sensitivities were 90.5%, 89%, 88.8%, and 96% for Kalazar Detect®, DiaMed-IT Leish®, DAT, and IFAT, respectively; DAT showed the highest estimated specificity (97.4%). Both rK39 immunochromatographic tests perform as well as DAT, and are suitable for VL diagnosis in first-level health centers in this area of Ethiopia. PMID:21212210

  2. Evaluation of agglutination strength by a flow-induced cell movement assay based surface plasmon resonance (SPR) technique.

    PubMed

    Sudprasert, Krisda; Peungthum, Patjaree; Vongsakulyanon, Apirom; Amarit, Ratthasart; Somboonkaew, Armote; Sutapun, Boonsong; Kitpoka, Pimpun; Kunakorn, Mongkol; Srikhirin, Toemsak

    2015-02-07

    A flow-induced cell movement assay combined with a surface plasmon resonance (SPR) technique was developed to quantify the agglutination strength, derived from the standard tube-agglutination test. Red blood cells (RBCs), based on the ABO blood group system, were specifically captured by anti-A and/or anti-B antibodies immobilized on a sensor surface. The agglutination strength corresponds to the amount of antigen-antibody interactions or the strength of RBC adhesion. Under a shear flow, the adherent RBCs were forced to move out of the region of interest with different average cell velocities (vc) depending upon the adhesion strength and wall shear stress (WSS). That is, a higher adhesion strength (higher agglutination strength) or lower WSS represents a lower vc or vice versa. In this work, the agglutination strength was derived from the vc that was calculated from the time derivative of the relative SPR signal by using a simple model of cell movement response, whose validity was verified. The vc values of different samples were correlated with their agglutination strengths at a given WSS and antibody surface density. The vc decreased as the agglutination strength increased, which can be considered as a linear regression. The coefficient of variation of the calculated vc decreased to 0.1 as vc increased to 30 μm min(-1). The sensitivity of this assay can be controlled by optimizing the antibody surface density or the WSS. This assay has the capability to resolve the antigen density of A1 and B RBCs from that of A1B RBCs.

  3. Prevalence of agglutinating antibodies to Toxoplasma gondii and Sarcocystis neurona in beavers (Castor canadensis) from Massachusetts

    USGS Publications Warehouse

    Jordan, C.N.; Kaur, T.; Koenen, K.; DeStefano, S.; Zajac, A.M.; Lindsay, D.S.

    2005-01-01

    The present study examined the seroprevalence of Toxoplasma gondii and Sarcocystls neurona in a population of beavers (Castor canadensis) from Massachusetts. Sixty-two blood samples were collected during the field seasons over 3 consecutive years from different animals. Blood was collected onto filter paper and shipped to the Department of Biomedical Sciences, Virginia Tech, Blacksburg, Virginia, for parasite testing. The samples were tested at dilutions of 1:25, 1:50, and 1:100 against each parasite antigen by modified agglutination tests to determine whether antibodies to either parasite were present in the blood. Six of 62 samples (10%) were positive for T. gondii, with 2 samples having titers of 1:25 and 4 having titers of 1:50. Four of 62 samples (6%) were positive for S. neurona, with 2 samples having titers of 1:25 and 2 having titers of 1:50. ?? American Society of Pathologists 2005.

  4. Red cell surface changes in cold agglutination

    PubMed Central

    Salsbury, A. J.; Clarke, J. A.; Shand, W. S.

    1968-01-01

    Surface changes in red blood cells undergoing cold agglutination have been investigated using the Cambridge Stereoscan electron microscope. On incubation of red cells with a cold agglutinin of anti-I specificity at 4°C, circular shadows on the red cell membrane developed within 2 min. At the same time the membrane showed a granularity and processes began to develop on the surface. These processes increased in length, the processes of contiguous cells became interlinked and agglutination was complete after incubation of 1 hr. On warming an agglutinated specimen, the process was reversed with separation of red cells and retraction of the finger-like processes to yield discrete red cells of normal appearance. The addition of heparin in vivo prevented agglutination but did not inhibit surface changes completely. Complement appeared to play no part in the production of cold agglutination due to these antibodies or in the reversal of agglutination by warming. The significance of the surface changes described in relation to previous information on the mechanism of agglutination, has been discussed. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:5655472

  5. Comparative evaluation of recombinant LigB protein and heat-killed antigen-based latex agglutination test with microscopic agglutination test for diagnosis of bovine leptospirosis.

    PubMed

    Nagalingam, Mohandoss; Thirumalesh, Sushma Rahim Assadi; Kalleshamurthy, Triveni; Niharika, Nakkala; Balamurugan, Vinayagamurthy; Shome, Rajeswari; Sengupta, Pinaki Prasad; Shome, Bibek Ranjan; Prabhudas, Krishnamsetty; Rahman, Habibur

    2015-10-01

    This study aimed to develop latex agglutination test (LAT) using recombinant leptospiral immunoglobulin-like protein (LigB) (rLigB) antigen and compare its diagnostic efficacy with LAT using conventional heat-killed leptospiral antigen and microscopic agglutination test (MAT) in diagnosing bovine leptospirosis. The PCR-amplified 1053-bp ligB gene sequences from Leptospira borgpetersenii Hardjo serovar were cloned in pET 32 (a) vector at EcoRI and NotI sites and expressed in BL21 E. coli cells as fusion protein with thioredoxin (-57 kDa) and characterized by SDS-PAGE and immunoblot. Out of 390 serum samples [cattle (n = 214), buffaloes (n = 176)] subjected to MAT, 115 samples showed reciprocal titre≥100 up to 1600 against one or more serovars. For recombinant LigB protein/antigen-based LAT, agglutination was observed in the positive sample, while no agglutination was observed in the negative sample. Similarly, heat-killed leptospiral antigen was prepared from and used in LAT for comparison with MAT. A two-sided contingency table was used for analysis of LAT using both the antigens separately against MAT for 390 serum samples. The sensitivity, specificity and positive and negative predictive values of recombinant LigB LAT were found to be 75.65, 91.27, 78.38 and 89.96 %, respectively, and that of heat-killed antigen-based LAT were 72.17, 89.82, 74.77 and 88.53 %, respectively, in comparison with MAT. This developed test will be an alternative/complementary to the existing battery of diagnostic assays/tests for specific detection of pathogenic Leptospira infection in bovine population.

  6. Production of latex agglutination reagents for pneumococcal serotyping

    PubMed Central

    2013-01-01

    Background The current ‘gold standard’ for serotyping pneumococci is the Quellung test. This technique is laborious and requires a certain level of training to correctly perform. Commercial pneumococcal latex agglutination serotyping reagents are available, but these are expensive. In-house production of latex agglutination reagents can be a cost-effective alternative to using commercially available reagents. This paper describes a method for the production and quality control (QC) of latex reagents, including problem solving recommendations, for pneumococcal serotyping. Results Here we describe a method for the production of latex agglutination reagents based on the passive adsorption of antibodies to latex particles. Sixty-five latex agglutination reagents were made using the PneuCarriage Project (PCP) method, of which 35 passed QC. The other 30 reagents failed QC due to auto-agglutination (n=2), no reactivity with target serotypes (n=8) or cross-reactivity with non-target serotypes (n=20). Dilution of antisera resulted in a further 27 reagents passing QC. The remaining three reagents passed QC when prepared without centrifugation and wash steps. Protein estimates indicated that latex reagents that failed QC when prepared using the PCP method passed when made with antiserum containing ≤ 500 μg/ml of protein. Sixty-one nasopharyngeal isolates were serotyped with our in-house latex agglutination reagents, with the results showing complete concordance with the Quellung reaction. Conclusions The method described here to produce latex agglutination reagents allows simple and efficient serotyping of pneumococci and may be applicable to latex agglutination reagents for typing or identification of other microorganisms. We recommend diluting antisera or removing centrifugation and wash steps for any latex reagents that fail QC. Our latex reagents are cost-effective, technically undemanding to prepare and remain stable for long periods of time, making them ideal for

  7. Ultraviolet and visible light spectrophotometric approach to blood typing: objective analysis by agglutination index.

    PubMed

    Narayanan, S; Orton, S; Leparc, G F; Garcia-Rubio, L H; Potter, R L

    1999-10-01

    A new blood typing technology based on ultraviolet (UV) and visible light spectroscopy (UV/visible spectroscopy) has been developed. Blood groups and types are determined by quantifying reproducible changes in the UV and visible light spectra of blood in the presence of agglutinating antibodies. Samples of red cells in the presence and absence of agglutinating antibodies were examined by UV/visible spectroscopy. Blood groups and types were determined by comparing the optical density spectra obtained between 665 and 1000 nm. These comparisons generate numbers (agglutination index) ranging from 0 to 100, with smaller numbers corresponding to lack of agglutination and larger numbers corresponding to agglutination. The optical density of agglutinated blood is dramatically different from that of unagglutinated blood. The agglutination index derived from the relative slopes of the spectra is an objective indicator of agglutination strength. An agglutination index greater than 17 consistently and accurately established blood group- and type-specific agglutination. The method accurately predicted A, B, and O blood groups, and D type in over 275 samples. Scattering theory-based calculations of relative volumes of red cells before and after agglutination show a direct correlation with the agglutination index and provide the theoretical basis of the analysis. This quantitative technique is reproducible and has the potential for automation.

  8. Evaluation of new monoclonal antibody-based latex agglutination test for detection of cryptococcal polysaccharide antigen in serum and cerebrospinal fluid.

    PubMed Central

    Kiska, D L; Orkiszewski, D R; Howell, D; Gilligan, P H

    1994-01-01

    We evaluated the performance of CRYPTO-LEX (Trinity Laboratories, Inc., Raleigh, N. C.), a new mouse immunoglobulin M monoclonal antibody latex agglutination reagent which reacts with the capsular polysaccharide of the four serogroups of Cryptococcus neoformans. This test was compared with CALAS (Meridian Diagnostics, Cincinnati, Ohio) for the ability to detect cryptococcal antigen in serum and cerebrospinal fluid (CSF). A total of 580 clinical specimens (327 serum and 253 CSF samples), primarily from human immunodeficiency virus-infected patients, were tested in this study. Sixty-seven specimens (44 serum and 23 CSF samples) were positive for cryptococcal antigen with both tests, and 511 (282 serum and 229 CSF samples) were negative. The two latex reagents agreed for 326 of 327 serum specimens (44 positives and 282 negatives). One serum specimen with a titer of 1:2 was CALAS positive but CRYPTO-LEX negative. The titer correlation coefficient for the two tests was 0.884 when two highly discordant serum specimens were eliminated from analysis of the data. The two latex tests agreed for 252 of 253 CSF specimens (23 positives and 229 negatives). One specimen with a titer of 1:2 was positive with CALAS and negative by CRYPTO-LEX. The correlation coefficient of the two tests for CSF titers was 0.886. The sensitivity and specificity of CRYPTO-LEX were 97 and 100%, respectively, with a 99.6% correlation with CALAS. These data show that the performance of CRYPTO-LEX is comparable to that of CALAS for detection of cryptococcal antigen in serum and CSF. PMID:7814566

  9. Expression of a recombinant human sperm-agglutinating mini-antibody in tobacco (Nicotiana tabacum L.).

    PubMed

    Xu, Bingfang; Copolla, Michael; Herr, John C; Timko, Michael P

    2007-01-01

    The murine monoclonal antibody (mAB) S19 recognizes an N-linked carbohydrate antigen designated sperm agglutination antigen-1 (SAGA1) located on the membrane protein CD52. This antigen is added to the sperm surface during epididymal maturation. Binding of the S19 mAB to SAGA-1 causes the rapid agglutination of sperm and blocks pre-fertilization events. Previous studies indicated that the S19 mAB may be a potential specific spermicidal agent (termed a spermistatic) capable of replacing current spermicidal products that contain harsh detergents with harmful side effects. The nucleotide sequences encoding the heavy (H) and light (L) chains of the S19 antibody were cloned. A chimeric gene was constructed using the nucleotide sequences encoding the variable regions of both the H and L chains, and this gene (scFv1 9) was expressed in transgenic tobacco (Nicotiana tabacum L.) to produce a recombinant anti-sperm antibody (RASA). Highest levels of RASA expression were observed in BY-2 plant cell suspension cultures and regenerated N. tabacum cv. Xanthi plants transformant in which the RASA coding sequences were expressed under the control of the Cauliflower Mosaic Virus 35S promoter containing a double-enhancer sequence (2X CaMV 35S). Subsequent modifications of the transgene including the addition of a 5'-untranslated sequence from the tobacco etch virus (TEV leader sequence), N-terminal fusion of the coding region with an endoplasmic reticulum targeting signal of patatin (pat) and C-terminal fusion with the endoplasmic reticulum retention signal peptide KDEL showed further enhancement of RASA expression. The plant-expressed RASA formed intrachain disulfide bonds and was primarily soluble in the cytoplasmic fraction of the cells. Introduction of a poly-histidine (6xHIS) tag in the recombinant RASA protein allowed for rapid purification of the recombinant protein using Ni-NTA chromatography. Optimization of scale-up production and purification of this plant

  10. Evaluation of the usefulness of six commercial agglutination assays for serologic diagnosis of toxoplasmosis.

    PubMed

    Villard, Odile; Cimon, Bernard; Franck, Jacqueline; Fricker-Hidalgo, Hélène; Godineau, Nadine; Houze, Sandrine; Paris, Luc; Pelloux, Hervé; Villena, Isabelle; Candolfi, Ermanno

    2012-07-01

    Six agglutination tests for detecting Toxoplasma gondii-specific antibodies (immunoglobulin G or M) in serum were performed and compared. In total, 599 sera were examined using direct and indirect agglutination assays. Sensitivity varied from 93.7% to 100% and specificity from 97.1% to 99.2%. In a selected population with interfering diseases, the percentage of false positives ranged from 4.3% to 10.9%. Although an overall agreement of 100% was found for chronic toxoplasmosis, sensitivity for the detection of confirmed acute toxoplasmosis ranged from 86.4% to 97.3%. Regarding the large variability in terms of the performance of the 6 assays, tests based on the hemagglutination principle were found to be better than the other agglutination tests for all the panels evaluated, meaning that they could be used as qualitative or semiquantitative low-cost screening assays. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Analysis of the 3D structure og agglutinated erythrocyte using CellScan and confocal microscopy: characterization by FLIM-FRET

    NASA Astrophysics Data System (ADS)

    Riquelme, Bibiana D.; Dumas, Dominique; Valverde de Rasia, Juana; Rasia, Rodolfo J.; Stoltz, Jean Francois

    2003-10-01

    We report the adhesion of human erythrocyte membranes mediated by monoclonal antibodies anti-glycophorin. The distribution of the linked antibodies on membrane was identified with selective fluorescence labels. To analyze the antibody distribution on interfacial region between two cells agglutinated and on its surface, three types of fluorescence marked strategy were evaluated. The 3D images were obtained in a CellScan and Confocal Laser Scanning Microscopy CLSM. We considered the FRET signal to characterize the agglutination of Red Blood Cells (RBC) by specific monoclonal antibodies (anti-glycophorin A or B). The fluorescence labeling demonstrated that distribution of antibody on erythrocyte membranes is not homogeneous. The fluorescence intensity on contact region in the agglutinated is bigger than the intensity on exterior surface. Tentatively, we interpreted these intensity differences in terms of the mobility of antibody linked to the glycocalix on cell surface. Such mobility has a large consequence in the morphology of cellular agglutinated.

  12. Evaluation of recombinant LigB antigen-based indirect ELISA and latex agglutination test for the serodiagnosis of bovine leptospirosis in India.

    PubMed

    Deneke, Yosef; Sabarinath, T; Gogia, Neha; Lalsiamthara, Jonathan; Viswas, K N; Chaudhuri, Pallab

    2014-08-01

    Leptospirosis is a zoonotic disease caused by pathogenic spirochetes of the genus Leptospira, causing febrile infection characterized by multi-organ failure in humans and animals. Leptospiral Ig-like protein B (LigB) is a surface-expressed antigen that mediates host cell invasion or attachment. In this study, N-terminal conserved region of LigB protein (46 kDa) was evaluated for its diagnostic potential to detect anti-leptospiral antibodies in the sera of various animal species. Dot blot analysis revealed immunoreactivity of Leptospira-positive sera of cattle, buffalo, dog, sheep and goat to purified LigB protein. We have analyzed 1126 bovine serum samples, collected from Northern and Eastern part of India, by microscopic agglutination test (MAT) and recombinant LigB (rLigB) based ELISA and latex agglutination test (LAT). The sensitivity of rLigB based ELISA for 554 MAT positive sera was 96.9% and the specificity with 572 MAT negative sera was 91.08% whereas LAT showed sensitivity and specificity of 93.68% and 92.31%, respectively. Kappa values of 0.879 and 0.860 for recombinant antigen based ELISA and LAT indicate excellent agreement with the gold standard serological test, MAT, for the detection of anti-leptospiral antibodies in sera. Further, LAT based on rLigB antigen is a simple and rapid test, suitable for serodiagnosis of leptospirosis under field conditions, owing to its portability and longer shelf life. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Automated point-of-care testing for ABO agglutination test: proof of concept and validation.

    PubMed

    El Kenz, H; Corazza, F

    2015-07-01

    ABO-incompatible red blood cell transfusions still represent an important hazard in transfusion medicine. Therefore, some countries have introduced a systematic bedside ABO agglutination test checking that the right blood is given to the right patient. However, this strategy requires an extremely time-consuming learning programme and relies on a subjective interpretation of ABO test cards agglutination. We developed a prototype of a fully automated device performing the bedside agglutination test that could be completed by reading of a barcoded wristband. This POCT checks the ABO compatibility between the patient and the blood bag. Proof of concept and analytical validation of the prototype has been completed on 451 blood samples: 238 donor packed red blood cells, 137 consecutive unselected patients for whom a blood group determination had been ordered and on 76 patient samples selected with pathology that could possibly interfere with or impair performances of the assay. We observed 100% concordance for ABO blood groups between the POCT and the laboratory instrument. These preliminary results demonstrate the feasibility of ABO determination with a simple POCT device eliminating manipulation and subjective interpretation responsible for transfusion errors. This device should be linked to the blood bank system allowing all cross-check of the results. © 2015 International Society of Blood Transfusion.

  14. Preventing Staphylococcus aureus Sepsis through the Inhibition of Its Agglutination in Blood

    PubMed Central

    McAdow, Molly; Kim, Hwan Keun; DeDent, Andrea C.; Hendrickx, Antoni P. A.; Schneewind, Olaf; Missiakas, Dominique M.

    2011-01-01

    Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci - coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA) – were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans. PMID:22028651

  15. Preventing Staphylococcus aureus sepsis through the inhibition of its agglutination in blood.

    PubMed

    McAdow, Molly; Kim, Hwan Keun; Dedent, Andrea C; Hendrickx, Antoni P A; Schneewind, Olaf; Missiakas, Dominique M

    2011-10-01

    Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci--coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA)--were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans.

  16. Evaluation of a rapid agglutination method for detection of equine red cell surface antigens (Ca and Aa) as part of pretransfusion testing.

    PubMed

    Owens, Sean D; Snipes, Joy; Magdesian, K Gary; Christopher, Mary M

    2008-03-01

    Blood typing before transfusion minimizes the risk of transfusion reactions and prevents immunization of the recipient against incompatible RBC antigens. The major RBC antigens that warrant identification before packed RBC or whole blood transfusions in horses are Ca and Aa. Standard blood-typing protocols are time-consuming (2.5-3.0 hours) and impractical in emergency settings. The purpose of this study was to determine whether equine RBCs could be typed for Ca and Aa antigens using sera from horses with RBC antibodies in a modified rapid (15 minute) blood-typing protocol. Serum was obtained from a horse with anti-Ca antibodies and from another horse with anti-Aa antibodies. The presence of agglutinating antibodies was confirmed with antibody screening. Venous blood samples, collected in citrate-phosphate-dextrose, were obtained from 21 horses of various breeds. Samples were blood typed in the Veterinary Medical Teaching Hospital Hematology Laboratory using standard methodology. Washed RBCs from each of the 21 horses were incubated individually with anti-Ca and anti-Aa sera at dilutions of 1:4, 1:8, and 1:16 for 15 and 30 minutes at room temperature and 37 degrees C. Of the 21 horses, 13 were identified as Aa+/Ca+, four were Aa+/Ca-, two were Aa-/Ca+, and two were Aa-/Ca-. All 17 Aa-positive horses had a positive agglutination reaction at all dilutions of anti-Aa serum, incubation times, and temperatures, while all Aa-negative horses were negative. Each Ca-positive horse had a positive agglutination reaction at all incubation time points and temperatures up to the 1:16 dilution of the anti-Ca serum. All Ca-negative horses were negative at all times, temperatures, and dilutions of anti-Ca serum. Use of the modified protocol on 26 hospitalized horses resulted in accurate typing, based on complete antibody screens. These results support the hypothesis that equine RBCs can be blood typed using a rapid (15 minute) protocol, at room temperature, for the presence of Ca

  17. Simplified spectraphotometric method for the detection of red blood cell agglutination.

    PubMed

    Ramasubramanian, Melur; Anthony, Steven; Lambert, Jeremy

    2008-08-01

    Human error is the most significant factor attributed to incompatible blood transfusions. A spectrophotometric approach to blood typing has been developed by examining the spectral slopes of dilute red blood cell (RBC) suspensions in saline, in the presence and absence of various antibodies, offering a technique for the quantitative determination of agglutination intensity [Transfusion39, 1051, 1999TRANAT0041-113210.1046/j.1537-2995.1999.39101051.x]. We offer direct theoretical prediction of the observed change in slope in the 660-1000 nm range through the use of the T-matrix approach and Lorenz-Mie theory for light scattering by dilute RBC suspensions. Following a numerical simulation using the T-matrix code, we present a simplified sensing method for detecting agglutination. The sensor design has been prototyped, fully characterized, and evaluated through a complete set of tests with over 60 RBC samples and compared with the full spectrophotometric method. The LED and photodiode pairs are found to successfully reproduce the spectroscopic determination of red blood cell agglutination.

  18. Elemental X-ray mapping of agglutinated foraminifer tests: A non- destructive technique for determining compositional characteristics.

    USGS Publications Warehouse

    Commeau, R.F.; Reynolds, Leslie A.; Poag, C.W.

    1985-01-01

    The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers. 

  19. [Yes, we should keep ABO agglutination test within bedside transfusion checks].

    PubMed

    Daurat, G

    2008-11-01

    ABO incompatible transfusions are still a frequent cause of serious adverse transfusion reactions. Bedside check is intended to detect patient errors and prevent ABO mismatch. France is one of the few countries that includes ABO agglutination test for red blood cells in bedside checks. Evaluation of this ABO agglutination test, performed with a special card, shows that, on the field, despite frequent users' mishandling, it can detect up to 93% of ABO incompatibilities. This is not enough to rely on this sole test for bedside checks. But, linking it with an another test, currently, checks that the right blood is given to the right patient, rises the sensitivity of the whole bedside procedure up to an estimated 99.65%, for detection of ABO incompatibilities. This linkage has been introduced in the French regulation in 2003. Since then, the incidence of ABO incompatible transfusions has decreased dramatically and faster than in any other country, so France has now, probably, the lowest rate of ABO incompatible transfusions. The investigation of the few ABO accidents that still occur, shows that professionals have always bypassed this linkage. On the other hand, introducing bedside recipient and blood products barcode or radio-chip checks in all the 1500 French hospitals, though technically possible, would provide very little enhancement and lead to major difficulties and expenses. Linkage of ABO agglutination test to patient and blood checks within the bedside procedure has proved to be efficient and should be kept.

  20. Latex agglutination inhibition card test for gentamicin assay: clinical evaluation and comparison with radioimmunoassay and bioassay.

    PubMed Central

    Standiford, H C; Bernstein, D; Nipper, H C; Caplan, E; Tatem, B; Hall, J S; Reynolds, J

    1981-01-01

    Gentamicin levels were determined in 100 serum specimens by a new latex agglutination inhibition card test, a radioimmunoassay (RIA), and a bioassay. Correlation coefficients determined by linear regression analysis demonstrated that the levels obtained by the latex agglutination inhibition card test had a high degree of correlation with the RIA and could be performed much faster and more economically when processing small numbers of specimens. The bioassay had a slightly lower degree of correlation with both the RIA and the latex test and was adversely influenced by concurrently administered antibiotics which could not be eliminated by beta-lactamase. When measuring gentamicin concentrations above 2 micrograms/ml, the coefficient of variation was less than 14% for the latex agglutination assay compared with 15% for the bioassay and 12% for RIA. The latex agglutination inhibition card test is a rapid, accurate, specific, and reproducible method for monitoring gentamicin levels in patients and is particularly applicable for laboratories processing small numbers of specimens. PMID:7247384

  1. Isolation and identification of Duck tembusu virus strain lH and development of latex-agglutination diagnostic method for rapid detection of antibodies.

    PubMed

    Wang, Quanxi; Wen, Yaping; Yifan Huang; Wu, Yijian; Cai, Yilong; Xu, Lihui; Wang, Changkang; Li, Ang; Wu, Baocheng; Chen, Jilong

    2014-12-01

    SUMMARY. An outbreak of egg-drop syndrome occurred on a Sheldrake duck farm in Longhai in Fujian Province, China, in 2012. The main clinical symptoms were sharply reduced egg production, crooked necks, and death. We isolated the virus from the sick ducks, identified it, and observed the histopathologic changes after viral infection. We detected viral RNA in the blood and feces of the infected ducks and developed a latex-agglutination diagnostic method to detect anti-Tembusu-virus antibodies. Our results show that the pathogenic virus is a Tembusu virus. The histopathologic changes included follicular cell degeneration and necrosis, follicular cavity filled with blood cells, massive necrosis in the brain, and degeneration and necrosis of the nerve and glial cells. When the transmission of the virus in the infected ducks was studied, the duck blood was positive for viral nucleic acid for up to 29 days, and the feces were positive for viral nucleic acid for up to 13 days. We successfully established a simple, rapid, and easy- to-use latex-agglutination diagnostic method for the detection of antibodies against duck Tembusu virus.

  2. SEROLOGICAL TYPING OF STAPHYLOCOCCI BY MEANS OF FLUORESCENT ANTIBODIES I.

    PubMed Central

    Cohen, Jay O.; Oeding, Per

    1962-01-01

    Cohen, Jay O. (Communicable Disease Center, Atlanta, Ga.) and Per Oeding. Serological typing of staphylococci by means of fluorescent antibodies. I. Development of specific reagents for seven serological factors. J. Bacteriol. 84:735–741. 1962—Fluorescent antibody reagents for identifying seven antigenic factors of staphylococci have been prepared. The fluorescent staining reactions of these reagents were compared to the agglutination reactions with diagnostic cultures of coagulase-positive staphylococci. Correlation between the two serological tests was almost complete with factors a, b, i, and k. The c fluorescent antibody reagent had a somewhat broader spectrum of activity than the corresponding agglutination serum, whereas the m fluorescent antibody reagent stained fewer strains than were agglutinated in m serum. The fluorescent antibody reagent for h factor stained strains possessing h1 factor but not strains possessing only h2 factor. Fluorescent antibody reagents for specific staphylococcal factors did not stain strains of group A streptococci. PMID:14022057

  3. Agglutination reactions of human leucocytes

    PubMed Central

    Schulz, Jeanette; Muller, Helga

    1963-01-01

    Agglutination tests with various sera and leucocytes from 58 leukaemic patients and 61 patients without leukaemia are reported. The agglutination of white blood cells by guinea-pig serum is of limited value in the diagnosis of leukaemia, though the test may be helpful in distinguishing leukaemia from other lymphomatous disorders. Leuco-autoagglutinins were demonstrated more frequently than expected. Eleven leukaemic and six non-leukaemic sera agglutinated autologous leucocytes. White blood cell agglutinins showed no apparent relationship to maturity or numbers of circulating leucocytes or to previous blood transfusions, x-irradiation, or therapy with antimetabolites. PMID:14044034

  4. Mononucleosis spot test

    MedlinePlus

    Monospot test; Heterophile antibody test; Heterophile agglutination test; Paul-Bunnell test; Forssman antibody test ... The mononucleosis spot test is done when symptoms of mononucleosis are ... Fatigue Fever Large spleen (possibly) Sore throat Tender ...

  5. Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis.

    PubMed

    Enabulele, Osahon; Awunor, Simeon Nyemike

    2016-01-01

    Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients. Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever. Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection. A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test.

  6. Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis

    PubMed Central

    Enabulele, Osahon; Awunor, Simeon Nyemike

    2016-01-01

    Background: Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients. Materials and Methods: Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever. Results: Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection. Conclusion: A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test. PMID:27397952

  7. Studying red blood cell agglutination by measuring membrane viscosity with optical tweezers

    NASA Astrophysics Data System (ADS)

    Fernandes, Heloise P.; Fontes, Adriana; de Thomaz, André A.; Barbosa, Luiz C.; Barjas-Castro, Maria L.; Cesar, Carlos L.

    2007-09-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycoproteins embedded in a fluid lipid bilayer that are responsible for cell agglutination. Manipulating RBCs rouleaux with a double optical tweezers, we observed that the cells slide easily one over the others but are strongly connected by their edges. An explanation for this behavior could be the fact that when the cells slide one over the others, proteins are dragged through the membrane. It confers to the movement a viscous characteristic that is dependent of the velocity between the RBCs and justifies why is so easy to slide them apart. Therefore, in a first step of this work, by measuring the force as a function of the relative velocity between two cells, we confirmed this assumption and used this viscous characteristic of the RBC rouleaux to determine the apparent membrane viscosity of the cell. As this behavior is related to the proteins interactions, we can use the apparent membrane viscosity to obtain a better understanding about cell agglutination. Methods related to cell agglutination induced by antigen-antibody interactions are the basis of most of tests used in transfusion centers. Then, in a second step of this work, we measured the apparent membrane viscosity using antibodies. We observed that this methodology is sensitive to different kinds of bindings between RBCs. Better comprehension of the forces and bindings between RBCs could improve the sensibility and specificity of the hemagglutination reactions and also guides the development of new potentiator substances.

  8. [Evaluation of the usefulness of the agglutination test with Mangifera indica extract for the identification of pathogenic Yersinia enterocolitica strains].

    PubMed

    Kałuzewski, S; Gierczyński, R; Szych, J; Jagielski, M

    1997-01-01

    The study was performed on 137 Y. enterocolitica strains belonging to various serological groups, including 75 03 group strains isolated form human clinical material. The agglutination test on slides was carried out on this strains using Mangifera indica extract of own production. Agglutinating preparation obtained from the seeds of M. indica agglutinated Y. enterocolitica organisms possessing the pVY plasmid and CRMOX+ phenotype in dilutions to 1.56 micrograms/ml. In identification tests conducted parallelly agglutination solution was used in concentrations of 100 and 10 micrograms/ml. All clones of Y. enterocolitica from O3 group from cultures at 37 degrees C and with CRMOX+ phenotype possessing the pVY plasmid were agglutinated by the extract. Agglutination failed to develop in the cultures of these clones incubated at 25 degrees C. Yersinia clones not containing the pVY plasmid with CRMOX- phenotype were resistant to agglutination. The virulence plasmid was found in 44 out of 75 strains of Y. enterocolitica O3 and was identified by restriction analysis after plasmid DNA digestion with Eco RI enzyme. The obtained results agreed with those of Wauters et al. in 1995 and confirmed the opinion of these authors on the usefulness of the test with M. indica agglutinin for the identification of virulent Y. enterocolitica strains.

  9. Neospora caninum and Toxoplasma gondii antibodies in dogs from Durango City, Mexico.

    PubMed

    Dubey, J P; Alvarado-Esquivel, C; Liesenfeld, O; Herrera-Flores, R G; Ramírez-Sánchez, B E; González-Herrera, A; Martínez-García, S A; Bandini, L A; Kwok, O C H

    2007-10-01

    Toxoplasma gondii and Neospora caninum are structurally similar parasites, with many hosts in common. The prevalence of antibodies to T. gondii and N. caninum was determined in sera from dogs from Durango City, Mexico. Using a modified agglutination test, antibodies to T. gondii were found in 52 (51.5%) of the 101 dogs with titers of 1:25 in 27, 1:50 in 11, 1:100 in 5, 1:200 in 4, 1:400 in 2, 1:800 in 2, and 1:3,200 or higher in 1. Antibodies to N. caninum were determined by the indirect immunofluorescent antibody test (IFAT) and the Neospora sp. agglutination test (NAT). Two of the 101 dogs had N. caninum antibodies; these dogs did not have T. gondii antibodies, supporting the specificity of the tests used. The N. caninum antibody titers of the 2 dogs were: 1:400 by IFAT and 1:200 by NAT in 1, and 1:25 by NAT and IFAT in the other. Results indicate that these 2 structurally similar protozoans are antigenically different.

  10. Sensitivity and specificity of typhoid fever rapid antibody tests for laboratory diagnosis at two sub-Saharan African sites

    PubMed Central

    Keddy, Karen H; Sooka, Arvinda; Letsoalo, Maupi E; Hoyland, Greta; Chaignat, Claire Lise; Morrissey, Anne B; Crump, John A

    2011-01-01

    Abstract Objective To evaluate three commercial typhoid rapid antibody tests for Salmonella Typhi antibodies in patients suspected of having typhoid fever in Mpumalanga, South Africa, and Moshi, United Republic of Tanzania. Methods The diagnostic accuracy of Cromotest® (semiquantitative slide agglutination and single tube Widal test), TUBEX® and Typhidot® was assessed against that of blood culture. Performance was modelled for scenarios with pretest probabilities of 5% and 50%. Findings In total 92 patients enrolled: 53 (57.6%) from South Africa and 39 (42.4%) from the United Republic of Tanzania. Salmonella Typhi was isolated from the blood of 28 (30.4%) patients. The semiquantitative slide agglutination and single-tube Widal tests had positive predictive values (PPVs) of 25.0% (95% confidence interval, CI: 0.6–80.6) and 20.0% (95% CI: 2.5–55.6), respectively. The newer typhoid rapid antibody tests had comparable PPVs: TUBEX®, 54.1% (95% CI: 36.9–70.5); Typhidot® IgM, 56.7% (95% CI: 37.4–74.5); and Typhidot® IgG, 54.3% (95% CI: 36.6–71.2). For a pretest probability of 5%, PPVs were: TUBEX®, 11.0% (95% CI: 6.6–17.9); Typhidot® IgM, 9.1% (95% CI: 5.8–14.0); and Typhidot® IgG, 11.0% (6.3–18.4). For a pretest probability of 50%, PPVs were: TUBEX®, 70.2% (95% CI: 57.3–80.5); Typhidot® IgM, 65.6% (95% CI: 54.0–75.6); and Typhidot® IgG, 70.0% (95% CI: 56.0–81.1). Conclusion Semiquantitative slide agglutination and single-tube Widal tests performed poorly. TUBEX® and Typhidot® may be suitable when pretest probability is high and blood cultures are unavailable, but their performance does not justify deployment in routine care settings in sub-Saharan Africa. PMID:21897484

  11. How to use … the Monospot and other heterophile antibody tests.

    PubMed

    Marshall-Andon, Tess; Heinz, Peter

    2017-08-01

    Epstein-Barr virus (EBV) is a highly prevalent virus, transmitted via saliva, which often causes asymptomatic infection in children but frequently results in infectious mononucleosis in adolescents. Heterophile antibody tests, including the Monospot test, are red cell or latex agglutination assays, which detect antired cell antibodies produced as part of a polyclonal antibody response occurring during EBV infection. Heterophile antibody tests are rapid, cheap and specific tests that can be performed from the onset of symptoms of infectious mononucleosis. In adolescents, heterophile antibody tests have high specificity and sensitivity in the diagnosis of primary acute EBV infection. However, the tests have low sensitivity and low negative predictive value in young children and are not useful under the age of 4. Heterophile tests may be positive in other viral infections, autoimmune disease and haematological malignancies, but do not appear to be positive in primary bacterial infection. Virus-specific serology is required in children under the age of 4 or if an older child is heterophile negative. Virus-specific serology allows diagnosis and the pattern of positivity and negativity enables the clinician to stage the EBV infection. Virus-specific serology appears to have better sensitivity in young children, but there is cross-reaction with other herpesvirus infections, a longer turnaround time and it is more expensive to perform. Further research is needed to establish which children benefit from and hence require testing for heterophile antibodies, the cost-effectiveness of EBV investigations and whether heterophile titres have predictive value for the severity of infection and the likelihood of complications. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  12. Evaluation of a latex agglutination assay for the identification of Burkholderia pseudomallei and Burkholderia mallei.

    PubMed

    Duval, Brea D; Elrod, Mindy G; Gee, Jay E; Chantratita, Narisara; Tandhavanant, Sarunporn; Limmathurotsakul, Direk; Hoffmaster, Alex R

    2014-06-01

    Cases of melioidosis and glanders are rare in the United States, but the etiologic agents of each disease (Burkholderia pseudomallei and Burkholderia mallei, respectively) are classified as Tier 1 select agents because of concerns about their potential use as bioterrorism agents. A rapid, highly sensitive, and portable assay for clinical laboratories and field use is required. Our laboratory has further evaluated a latex agglutination assay for its ability to identify B. pseudomallei and B. mallei isolates. This assay uses a monoclonal antibody that specifically recognizes the capsular polysaccharide produced by B. pseudomallei and B. mallei, but is absent in closely related Burkholderia species. A total of 110 B. pseudomallei and B. mallei were tested, and 36 closely related Burkholderia species. The latex agglutination assay was positive for 109 of 110 (99.1% sensitivity) B. pseudomallei and B. mallei isolates tested. © The American Society of Tropical Medicine and Hygiene.

  13. Preliminary evaluation of a gel tube agglutination major cross-match method in dogs.

    PubMed

    Villarnovo, Dania; Burton, Shelley A; Horney, Barbara S; MacKenzie, Allan L; Vanderstichel, Raphaël

    2016-09-01

    A major cross-match gel tube test is available for use in dogs yet has not been clinically evaluated. This study compared cross-match results obtained using the gel tube and the standard tube methods for canine samples. Study 1 included 107 canine sample donor-recipient pairings cross-match tested with the RapidVet-H method gel tube test and compared results with the standard tube method. Additionally, 120 pairings using pooled sera containing anti-canine erythrocyte antibody at various concentrations were tested with leftover blood from a hospital population to assess sensitivity and specificity of the gel tube method in comparison with the standard method. The gel tube method had a good relative specificity of 96.1% in detecting lack of agglutination (compatibility) compared to the standard tube method. Agreement between the 2 methods was moderate. Nine of 107 pairings showed agglutination/incompatibility on either test, too few to allow reliable calculation of relative sensitivity. Fifty percent of the gel tube method results were difficult to interpret due to sample spreading in the reaction and/or negative control tubes. The RapidVet-H method agreed with the standard cross-match method on compatible samples, but detected incompatibility in some sample pairs that were compatible with the standard method. Evaluation using larger numbers of incompatible pairings is needed to assess diagnostic utility. The gel tube method results were difficult to categorize due to sample spreading. Weak agglutination reactions or other factors such as centrifuge model may be responsible. © 2016 American Society for Veterinary Clinical Pathology.

  14. Agglutination of Helicobacter pylori coccoids by lectins

    PubMed Central

    Khin, Mar Mar; Hua, Jie Song; Ng, Han Cong; Wadström, Torkel; Ho, Bow

    2000-01-01

    AIM: To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms. METHODS: Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS: Strong agglutination was observed with mannose-specific Concanavalin A (Con A), fucose-specific Tetragonolobus purpureas (Lotus A) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori lectin agglutination. Interes tingly, heating of H. pylori cells at 60 °C for 1 h was shown to augment the agglutination with all of the lectins tested. CONCLUSION: The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during the events of morphological transformation, resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection. This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease. PMID:11819557

  15. Assessment of red blood cell parameters and peripheral smear at different temperatures in case of cold agglutination disease.

    PubMed

    Gupta, V

    2014-03-01

    Cold agglutination disease (CAD) is characterized by an auto-antibody which is able to agglutinate red blood cells (RBCs) at temperatures lower than that of the body, and subsequently to activate the complement system responsible for lysis of RBCs. Patients show hemolytic anemia of varying degrees of severity, which arise or worsen upon exposure to low temperatures. We describe a case who presented with fever and symptoms of asthenia. His investigations yielded bizarre RBC parameters which led to suspicion of a rare CAD, which was confirmed on reviewing RBC parameters, peripheral smear and direct Coomb's test at different temperatures. Hence, we suggest assessment of bizarre RBC parameters and peripheral smear can help in laboratory testing and diagnosis of CAD. It should also not pose embarrassment in laboratory testing to the pathologist for making an early and accurate diagnosis, thus emphasizing the need for an early treatment of CAD.

  16. The usefulness of direct agglutination test, enzyme-linked immunosorbent assay and polymerase chain reaction for the detection of Toxoplasma gondii in wild animals.

    PubMed

    Kornacka, Aleksandra; Cybulska, Aleksandra; Bień, Justyna; Goździk, Katarzyna; Moskwa, Bożena

    2016-09-15

    The aim of the study was to compare the usefulness of two antibody-based methods, the direct agglutination test (DAT) and enzyme linked immuosorbent assay (ELISA), with that of the polymerase chain reaction (PCR) for detecting anti-Toxoplasma gondii in samples derived from naturally-infected wild animals. Antibodies against T. gondii were detected in meat juice samples collected from 129 free- living carnivores and omnivores. T. gondii seroprevalence was confirmed in 73,6% of examined samples when DAT and ELISA were used separately, but in only 88,4% samples when both immunological tests were used in parallel. PCR results confirmed the presence of DNA of the parasite in 24 of all the 129 samples. Sixteen samples were classified as positive when all three tests were used. A moderate degree of agreement was found between DAT and ELISA (κ=0.55). However, no agreement was found between the molecular and serological tests: κ=-1.75 for DAT versus PCR; κ=-1.67 ELISA versus PCR. By using both serological tests, antibodies against T. gondii were found in 77.5% of red foxes, 12.5% of badgers, 40% of martens and 8.3% of raccoon dogs. Antibodies against the parasite were detected also in one mink, but not in the sample derived from a polecat. T.gondii DNA was found in the brain tissue of 20 red foxes, three badgers and one raccoon dog. Our studies confirm that ELISA and DAT are suitable and reliable techniques for T. gondii antibody detection in meat juice from wild animals when serum samples are unavailable. Positive results obtained by immunological tests do not always reflect that the host was infected by T. gondii. They indicate only a contact with parasite. PCR should be used to confirm te presence of DNA from T. gondii. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Detection of Salmonella enterica serovar Enteritidis (SE) Antibodies in Serum Using A Polystyrene Bead/SE Flagella Agglutination Assay

    USDA-ARS?s Scientific Manuscript database

    Serologic screening of flocks can be an important method to detect Salmonella enteritidis (SE) infections but can be labor intensive or lack specificity. Our goal was to develop a rapid agglutination assay using SE flagella adsorbed to polystyrene beads as a simple, relatively specific test to dete...

  18. Prevalence of antibodies to Neospora caninum, Sarcocystis neurona, and Toxoplasma gondii in wild horses from central Wyoming.

    PubMed

    Dubey, J P; Mitchell, S M; Morrow, J K; Rhyan, J C; Stewart, L M; Granstrom, D E; Romand, S; Thulliez, P; Saville, W J; Lindsay, D S

    2003-08-01

    Sarcocystis neurona, Neospora caninum, N. hughesi, and Toxoplasma gondii are 4 related coccidians considered to be associated with encephalomyelitis in horses. The source of infection for N. hughesi is unknown, whereas opossums, dogs, and cats are the definitive hosts for S. neurona, N. caninum, and T. gondii, respectively. Seroprevalence of these coccidians in 276 wild horses from central Wyoming outside the known range of the opossum (Didelphis virginiana) was determined. Antibodies to T. gondii were found only in 1 of 276 horses tested with the modified agglutination test using 1:25, 1:50, and 1:500 dilutions. Antibodies to N. caninum were found in 86 (31.1%) of the 276 horses tested with the Neospora agglutination test--the titers were 1:25 in 38 horses, 1:50 in 15, 1:100 in 9, 1:200 in 8, 1:400 in 4, 1:800 in 2, 1:1,600 in 2, 1:3,200 in 2, and 1:12,800 in 1. Antibodies to S. neurona were assessed with the serum immunoblot; of 276 horses tested, 18 had antibodies considered specific for S. neurona. Antibodies to S. neurona also were assessed with the S. neurona direct agglutination test (SAT). Thirty-nine of 265 horses tested had SAT antibodies--in titers of 1:50 in 26 horses and 1:100 in 13. The presence of S. neurona antibodies in horses in central Wyoming suggests that either there is cross-reactivity between S. neurona and some other infection or a definitive host other than opossum is the source of infection. In a retrospective study, S. neurona antibodies were not found by immunoblot in the sera of 243 horses from western Canada outside the range of D. virginiana.

  19. Comparison of Buffered, Acidified Plate Antigen to Standard Serologic Tests for the Detection of Serum Antibodies to Brucella abortus in Elk (Cervus canadensis).

    PubMed

    Clarke, P Ryan; Edwards, William H; Hennager, Steven G; Block, Jean F; Yates, Angela M; Ebel, Eric; Knopp, Douglas J; Fuentes-Sanchez, Antonio; Jennings-Gaines, Jessica; Kientz, Rebecca L; Simunich, Marilyn

    2015-07-01

    Brucellosis (caused by the bacterium Brucella abortus) is a zoonotic disease endemic in wild elk (Cervus canadensis) of the Greater Yellowstone Ecosystem, US. Because livestock and humans working with elk or livestock are at risk, validated tests to detect the B. abortus antibody in elk are needed. Using the κ-statistic, we evaluated the buffered, acidified plate antigen (BAPA) assay for agreement with the results of the four serologic tests (card test [card], complement fixation test [CF], rivanol precipitation plate agglutination test [RIV], standard plate agglutination test [SPT]) that are approved by the US Department of Agriculture for the detection of the B. abortus antibody in elk. From 2006 to 2010, serum samples collected from elk within B. abortus-endemic areas (n = 604) and nonendemic areas (n = 707) and from elk culture-positive for B. abortus (n = 36) were split and blind tested by four elk serum diagnostic laboratories. κ-Values showed a high degree of agreement for the card (0.876), RIV (0.84), and CF (0.774) test pairings and moderate agreement for the SPT (0.578). Sensitivities for the BAPA, card, RIV, CF, and SPT were 0.859, 0.839, 0.899, 1.00, and 0.813, whereas specificities were 0.986, 0.993, 0.986, 0.98, and 0.968, respectively. The positive predictive values and the negative predictive values were calculated for 2.6%, 8.8%, and 16.2% prevalence levels. These findings suggest the BAPA test is a suitable screening test for the B. abortus antibodies in elk.

  20. Studying red blood cell agglutination by measuring electrical and mechanical properties with a double optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Fernandes, Heloise P.; de Thomaz, André A.; Barbosa, Luiz C.; Barjas-Castro, Maria L.; Cesar, Carlos L.

    2007-07-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycolproteins embedded in, or attached, to a fluid lipid bilayer and are negatively charged, which creates a repulsive electric (zeta) potential between the cells and prevents their aggregation in the blood stream. The basis of the immunohematologic tests is the interaction between antigens and antibodies that causes hemagglutination. The identification of antibodies and antigens is of fundamental importance for the transfusional routine. This agglutination is induced by decreasing the zeta-potential through the introduction of artificial potential substances. This report proposes the use of the optical tweezers to measure the membrane viscosity, the cell adhesion, the zeta-potential and the size of the double layer of charges (CLC) formed around the cell in an electrolytic solution. The adhesion was quantified by slowly displacing two RBCs apart until the disagglutination. The CLC was measured using the force on the bead attached to a single RBC in response to an applied voltage. The zeta-potential was obtained by measuring the terminal velocity after releasing the RBC from the optical trap at the last applied voltage. For the membrane viscosity experiment, we trapped a bead attached to RBCs and measured the force to slide one RBC over the other as a function of the relative velocity. After we tested the methodology, we performed measurements using antibody and potential substances. We observed that this experiment can provide information about cell agglutination that helps to improve the tests usually performed in blood banks. We also believe that this methodology can be applied for measurements of zeta-potentials in other kind of samples.

  1. Multicentre evaluation of a direct agglutination test prototype kit (DAT-LPC) for diagnosis of visceral leishmaniasis.

    PubMed

    Oliveira, E; Oliveira, D; Cardoso, F A; Barbosa, J R; Marcelino, A P; Dutra, T; Araujo, T; Fernandes, L; Duque, D; Rabello, A

    2017-12-01

    In this study, we assessed the sensitivity, specificity, and diagnostic accuracy of a previously developed direct agglutination test (DAT) using a freeze-dried antigen derived from Leishmania infantum promastigotes and composed in a prototype kit for visceral leishmaniasis (VL) diagnosis, named DAT-LPC. To evaluate DAT-LPC reproducibility, the kit was used to analyse 207 serum samples from VL patients and 80 serum samples from patients with other parasitic infections or healthy subjects in four laboratories from different public health institutions in Brazil. DAT-LPC showed sensitivity between 96·2 and 99·5% (P = 0·14), specificity ranging from 96·2 to 97·5% (P = 0·95), and diagnostic accuracy ranging from 96·5 to 99% (P = 0·34). The inter-laboratory reproducibility of qualitative results was classified as excellent (κ index: 0·94-0·97). The reproducibility of the end-titre results in relation to the reference laboratory, ranged from 31 to 85%. These results demonstrate an excellent performance of the DAT-LPC, and validate it for the diagnosis of VL that could replace the immunofluorescent antibody test as the routine diagnostic test in the Brazilian public health system.

  2. Studies of the antibody nature of the rheumatoid factor

    PubMed Central

    Aho, K.; Harboe, M.; Leikola, J.

    1964-01-01

    The reaction of the rheumatoid factor (RF) with 7S γ-globulin antibodies of nine persons immunized with sheep erythrocytes was studied. All of a panel of rheumatoid sera with high Waaler-Rose titres agglutinated sheep cells sensitized with the human anti-sheep cell antibodies and O Rh positive cells sensitized with the `diagnostic' anti-CD serum Ripley. The RF measurable with these systems could be absorbed to diphtheria toxoid—human antitoxin precipitate, whereas the absorption with egg albumin—rabbit anti-egg albumin precipitate did not result in any appreciable titre reduction. However, the eluate from the rabbit precipitate was highly active in these systems, whereas Rh positive cells sensitized with anti-Rh sera suitable for Gm(a) typing were not regularly agglutinated. A markedly greater concentration of native than of heat-aggregated γ-globulin was needed for inhibition of the agglutination by the RF of cells heavily sensitized with the human anti-sheep cell antibodies. No appreciable difference in this respect was seen when using lightly sensitized cells. Only the heavily sensitized cells fixed complement. The `natural' 7S γ-globulin antibodies against sheep cells were neither suited for demonstration of RF nor did they fix complement. Sheep cells coated with 7S γ-globulin antibodies of a Gm(a+) person were agglutinated by a non-rheumatoid anti-Gm(a) serum, and this system was well suited for Gm(a) typing, whereas cells coated with antibodies of a Gm(a-) person were not agglutinated. Rheumatoid anti-Gm(a) sera agglutinated cells sensitized with antibodies of both Gm(a+) and Gm(a-) persons. Using cells coated with Gm(a+) antibodies, some distinction between Gm(a+) and Gm(a-) sera could be obtained under carefully controlled conditions. The use of a Gm(a-) coat resulted in a slight difference in the inhibiting capacity, which had no relation to the serum's Gm(a) type. The results suggest that the reaction of the RF with sheep cells heavily sensitized

  3. PREVALENCE OF ANTIBODIES AGAINST TOXOPLASMA GONDII IN POLAR BEARS (URSUS MARITIMUS) FROM SVALBARD AND EAST GREENLAND

    USDA-ARS?s Scientific Manuscript database

    Serum samples from 419 polar bears (Ursus maritimus) from Svalbard and the Barents Sea (collected 1990 - 2000) and 108 polar bears from East Greenland (collected 1999 - 2004) were assayed for antibodies against Toxoplasma gondii using the modified agglutination test (MAT). Antibody prevalences were ...

  4. Prevalence of antibodies to Leishmania infantum and Toxoplasma gondii in horses from the north of Portugal

    USDA-ARS?s Scientific Manuscript database

    Background Leishmania infantum and Toxoplasma gondii are protozoa with zoonotic and economic importance. Prevalences of antibodies to these agents were assessed in 173 horses from the north of Portugal. Findings Antibodies to L. infantum were detected by the direct agglutination test (DAT); seven (...

  5. Rapid detection of hepatitis B virus surface antigen by an agglutination assay mediated by a bispecific diabody against both human erythrocytes and hepatitis B virus surface antigen.

    PubMed

    Chen, Yu-Ping; Qiao, Yuan-Yuan; Zhao, Xiao-Hang; Chen, Hong-Song; Wang, Yan; Wang, Zhuozhi

    2007-06-01

    Bispecific antibodies have immense potential for use in clinical applications. In the present study, a bispecific diabody against human red blood cells (RBCs) and hepatitis B virus surface antigen (HBsAg) was used to detect HBsAg in blood specimens. The bispecific diabody was constructed by crossing over the variable region of the heavy chains and the light chains of anti-RBC and anti-HBsAg antibodies with a short linker, SRGGGS. In enzyme-linked immunosorbent assays, this bispecific diabody showed specific binding to both RBCs and HBsAg. When this bispecific diabody was mixed with human blood specimens in the presence of HBsAg, the dual binding sites of the diabody caused agglutination of human RBCs. This diabody-mediated agglutination assay was then used to test 712 clinical blood specimens and showed 97.7% sensitivity and 100% specificity when the results were compared with those of the conventional immunoassay, which was used as a reference. This autologous RBC agglutination assay provides a simple approach for rapid screening for HBsAg in blood specimens.

  6. Rapid Detection of Hepatitis B Virus Surface Antigen by an Agglutination Assay Mediated by a Bispecific Diabody against Both Human Erythrocytes and Hepatitis B Virus Surface Antigen▿

    PubMed Central

    Chen, Yu-Ping; Qiao, Yuan-Yuan; Zhao, Xiao-Hang; Chen, Hong-Song; Wang, Yan; Wang, Zhuozhi

    2007-01-01

    Bispecific antibodies have immense potential for use in clinical applications. In the present study, a bispecific diabody against human red blood cells (RBCs) and hepatitis B virus surface antigen (HBsAg) was used to detect HBsAg in blood specimens. The bispecific diabody was constructed by crossing over the variable region of the heavy chains and the light chains of anti-RBC and anti-HBsAg antibodies with a short linker, SRGGGS. In enzyme-linked immunosorbent assays, this bispecific diabody showed specific binding to both RBCs and HBsAg. When this bispecific diabody was mixed with human blood specimens in the presence of HBsAg, the dual binding sites of the diabody caused agglutination of human RBCs. This diabody-mediated agglutination assay was then used to test 712 clinical blood specimens and showed 97.7% sensitivity and 100% specificity when the results were compared with those of the conventional immunoassay, which was used as a reference. This autologous RBC agglutination assay provides a simple approach for rapid screening for HBsAg in blood specimens. PMID:17442848

  7. Age-Related Buildup of Humoral Immunity against Epitopes for Rosette Formation and Agglutination in African Areas of Malaria Endemicity

    PubMed Central

    Barragan, Antonio; Kremsner, Peter G.; Weiss, Walter; Wahlgren, Mats; Carlson, Johan

    1998-01-01

    In this report, we show an age-related buildup of agglutinating activity as well as serum activity against rosette formation in children living in areas of Kenya and Gabon where malaria is endemic. Sera from Kenyans in general exhibited a stronger and wider immune response toward the epitopes, probably reflecting a difference in transmission patterns between the two areas. Thus, our results indicate that repeated malaria attacks in areas of endemicity, and consequently exposure to different isolate-specific antigens, will elicit an antibody-mediated response eventually enabling recognition of the majority of rosetting and agglutinating antigens. The correlation between antirosetting and agglutinating capacity was poor in individual cases, indicating that the rosetting epitopes are only a minor part of the highly diverse surface-exposed antigens (mainly PfEMP1) on the surface of parasitized erythrocytes toward which antibodies may react. These data together with our previous findings that the protection against cerebral malaria correlates with presence of antirosetting antibodies shed new light on our understanding of the gradual acquisition of immunity toward severe complications of malarial infection which children reared in areas of endemicity attain. PMID:9746579

  8. Detection of antibodies against Sarcocystis neurona, neospora spp., and Toxoplasma gondii in horses from Costa Rica

    USDA-ARS?s Scientific Manuscript database

    Serum samples from 315 horses from Costa Rica, Central America were examined for the presence of antibodies against Sarcocystis neurona, Neospora spp., and Toxoplasma gondii using the SnSAG2 ELISA, the NhSAG1 ELISA, and the modified agglutination test, respectively. Anti-S. neurona antibodies were f...

  9. Simulation of Mechanical Behavior of Agglutinates

    NASA Technical Reports Server (NTRS)

    Nakagawa, Masami; Moon, Tae-Hyun

    2005-01-01

    Due to lack of "real" lunar soil or even lunar simulant, it is difficult to characterize the interaction between lunar soil (or simulant) with different surfaces that are involved in excavation and processing machinery. One unique feature possessed by lunar soil is the agglutinates produced by repeated high-speed micrometeoroid impacts and subsequent pulverization[l and 2]. The large particles are impacted by micrometeoroids [Fig.l] and pulverized to produce finer particles. This process continues until there are no more "large" particles left on the surface of the moon. Due to high impact speed, the impact melting process fuses fines to make agglutinates such as shown in Fig. 2. We will present a series of simulation results and movies will be shown to indicate brittle behavior of each individual agglutinate and also similar compressibility charts shown by Carrier et al. [3]. Fig. 3 shows our preliminary result of the simulated oedometer tests.

  10. The increased flexibility of CDR loops generated in antibodies by Congo red complexation favors antigen binding.

    PubMed

    Krol, Marcin; Roterman, Irena; Drozd, Anna; Konieczny, Leszek; Piekarska, Barbara; Rybarska, Janina; Spolnik, Paweł; Stopa, Barbara

    2006-02-01

    The dye Congo red and related self-assembling compounds were found to stabilize immune complexes by binding to antibodies currently engaged in complexation to antigen. In our simulations, it was shown that the site that becomes accessible for binding the supramolecular dye ligand is located in the V domain, and is normally occupied by the N-terminal polypeptide chain fragment. The binding of the ligand disrupts the beta-structure in the domain, increasing the plasticity of the antigen-binding site. The higher fluctuation of CDR-bearing loops enhances antigen binding, and allows even low-affinity antibodies to be engaged in immune complexes. Experimental observations of the enhancement effect were supported by theoretical studies using L lambda chain (4BJL-PDB identification) and the L chain from the complex of IgM-rheumatoid factor bound to the CH3 domain of the Fc fragment (1ADQ-PDB identification) as the initial structures for theoretical studies of dye-induced changes. Commercial IgM-type rheumatoid factor (human) and sheep red blood cells with coupled IgG (human) were used for experimental tests aimed to reveal the dye-enhancement effect in this system. The specificity of antigen-antibody interaction enhanced by dye binding was studied using rabbit anti-sheep red cell antibodies to agglutinate red cells of different species. Red blood cells of hoofed mammals (horse, goat) showed weak enhancement of agglutination in the presence of Congo red. Neither agglutination nor enhancement were observed in the case of human red cells. The dye-enhancement capability in the SRBC-antiSRBC system was lost after pepsin-digestion of antibodies producing (Fab)2 fragments still agglutinating red cells. Monoclonal (myeloma) IgG, L lambda chain and ovoalbumin failed to agglutinate red cells, as expected, and showed no enhancement effect. This indicates that the enhancement effect is specific.

  11. Prevalence of antinuclear and anti-erythrocyte antibodies in healthy cats.

    PubMed

    Abrams-Ogg, Anthony C G; Lim, Sophia; Kocmarek, Helen; Ho, Kim; Blois, Shauna L; Shewen, Patricia E; Wood, R Darren; Bienzle, Dorothee

    2018-03-01

    Positive antinuclear antibody and direct antiglobulin tests support diagnoses such as systemic lupus erythematosus and immune-mediated anemia, respectively. Positive tests may occur in cats, but the prevalence of positive results in healthy cats is not well known. The study's purpose was to determine prevalences of positive antinuclear antibody and direct antiglobulin tests in healthy cats. Antinuclear antibody titers were measured by indirect immunofluorescence, and anti-erythrocyte antibodies were measured by the microtitration direct antiglobulin test at 37, 23, and 4°C in 61 client-owned and 28 facility-owned cats. Differences between the 2 groups were examined using chi-squared tests. For the antinuclear antibody tests, 70% of client-owned cats were negative, 10% had weak titers (1:40-1:80), and 20% had strong titers (1:160-1:320). Facility-owned cats had significantly fewer positive titers with 96% negative and one positive (1:8). For the antiglobulin test at 37°C, 93% of all cats were negative, 2 cats in each group were positive at low dilutions (1:2), and 2 client-owned cats were transiently positive at high dilutions (≥ 1:2048). At 23°C, 90% of all cats were negative, and 2 client-owned and 5 facility-owned cats were positive at low dilutions (1:2-1:8). At 4°C, 67% of client-owned cats had invalid results (negative control well agglutination), and 33% had negative results, while of facility-owned cats 14% had invalid results, 14% had agglutination at low dilutions, and 72% were negative. Healthy cats may have positive antinuclear antibody and direct antiglobulin tests, but the prevalence of strong reactions is low. © 2018 American Society for Veterinary Clinical Pathology.

  12. Chemical aspects of agglutinate formation - Relationships between agglutinate composition and the composition of the bulk soil. [lunar surface composition

    NASA Technical Reports Server (NTRS)

    Via, W. N.; Taylor, L. A.

    1976-01-01

    Attention is centered on the nature and intensity of geochemical fractionation accompanying agglutination of several size fractions of the immature Apollo-16 soil sample 67460, from North Ray Crater. The soil features coarse mean grain size about 150 microns, low (20 wt.%) magnetic agglutinate content, and a bimodal grain size distribution. The magnetic fraction included both agglutinates and magnetic non-agglutinates (glass-free microbreccias with 30-60 micron native FeNi grains hosted in a matrix of pyroxene, ilmenite, and olivine). The separation process residue contained nonmagnetic agglutinates with compositions near pure plagioclase. The magnetic agglutinate fraction appears selectively enriched in ferromagnesian elements to the partial exclusion of plagioclase elements. Agglutinate glass chemistry based solely on magnetic separation is deprecated on the basis of the results.

  13. Development of a simple and rapid method for the specific identification of organism causing anthrax by slide latex agglutination.

    PubMed

    Sumithra, T G; Chaturvedi, V K; Gupta, P K; Sunita, S C; Rai, A K; Kutty, M V H; Laxmi, U; Murugan, M S

    2014-05-01

    A specific latex agglutination test (LAT) based on anti-PA (protective antigen) antibodies having detection limit of 5 × 10(4) formalin treated Bacillus anthracis cells or 110 ng of PA was optimized in this study. The optimized LAT could detect anthrax toxin in whole blood as well as in serum from the animal models of anthrax infection. The protocol is a simple and promising method for the specific detection of bacteria causing anthrax under routine laboratory, as well as in field, conditions without any special equipments or expertise. The article presents the first report of a latex agglutination test for the specific identification of the cultures of bacteria causing anthrax. As the test is targeting one of anthrax toxic protein (PA), this can also be used to determine virulence of suspected organisms. At the same time, the same LAT can be used directly on whole blood or sera samples under field conditions for the specific diagnosis of anthrax. © 2013 The Society for Applied Microbiology.

  14. QUANTITATIVE ASPECTS OF THE RED BLOOD CELL AGGLUTINATION TEST FOR INFLUENZA VIRUS

    PubMed Central

    Miller, Gail Lorenz; Stanley, W. M.

    1944-01-01

    A detailed study has been made of the nature of the variables inherent in the chicken red cell agglutination test for influenza virus in an effort to obtain a method of measurement of biological activity of sufficient accuracy that it might be employed as a reliable index of chemical purity of preparations of the virus. It was found that the temperature at which the test is conducted has a marked effect on the titer, whereas within the range of pH 6–8 the pH has a negligible effect. It was also found that a variation in results may be encountered due to a variation in the specific behavior of red cells from different chickens and to an instability of the red cells themselves. Preparations of purified influenza virus held at 4°C., on the other hand, were found to be stable with respect to chicken red cell agglutinating activity for several months. This fact, together with the fact that in duplicate measurements upon different samples the accuracy was such that the chances were 19 out of 20 that differences of 8.4 per cent in the mean end points were significant, made it possible to establish a reproducible standard of CCA activity based on a unit weight of purified virus material. As a result, it was possible to devise a standardized procedure for carrying out with high accuracy quantitative measurements of influenza virus. PMID:19871362

  15. Diagnosis of myocardial infarction based on lectin-induced erythrocyte agglutination: a feasibility study

    NASA Astrophysics Data System (ADS)

    Bocsi, József; Nieschke, Kathleen; Mittag, Anja; Reichert, Thomas; Laffers, Wiebke; Marecka, Monika; Pierzchalski, Arkadiusz; Piltz, Joachim; Esche, Hans-Jürgen; Wolf, Günther; Dähnert, Ingo; Baumgartner, Adolf; Tarnok, Attila

    2014-03-01

    Myocardial infarction (MI) is an acute life-threatening disease with a high incidence worldwide. Aim of this study was to test lectin-carbohydrate binding-induced red blood cell (RBC) agglutination as an innovative tool for fast, precise and cost effective diagnosis of MI. Five lectins (Ricinus communis agglutinin (RCA), Phaseolus vulgaris erythroagglutinin (PHA), Datura stramonium agglutinin (DSA), Artocarpus agglutinin (ArA), Triticum agglutinin (TA)) were tested for ability to differentiate between agglutination characteristics in patients with MI (n = 101) or angina pectoris without MI (AP) (n = 34) and healthy volunteers (HV) as control (n =68) . RBC agglutination was analyzed by light absorbance of a stirred RBC suspension in the green to red light spectrum in an agglutimeter (amtec, Leipzig, Germany) for 15 min after lectin addition. Mean cell count in aggregates was estimated from light absorbance by a mathematical model. Each lectin induced RBC agglutination. RCA led to the strongest RBC agglutination (~500 RBCs/aggregate), while the others induced substantially slower agglutination and lead to smaller aggregate sizes (5-150 RBCs/aggregate). For all analyzed lectins the lectin-induced RBC agglutination of MI or AP patients was generally higher than for HV. However, only PHA induced agglutination that clearly distinguished MI from HV. Variance analysis showed that aggregate size after 15 min. agglutination induced by PHA was significantly higher in the MI group (143 RBCs/ aggregate) than in the HV (29 RBC-s/aggregate, p = 0.000). We hypothesize that pathological changes during MI induce modification of the carbohydrate composition on the RBC membrane and thus modify RBC agglutination. Occurrence of carbohydrate-lectin binding sites on RBC membranes provides evidence about MI. Due to significant difference in the rate of agglutination between MI > HV the differentiation between these groups is possible based on PHA-induced RBC-agglutination. This novel assay

  16. Antibodies to biotinylated red blood cells in adults and infants: improved detection, partial characterization, and dependence on red blood cell-biotin dose.

    PubMed

    Schmidt, Robert L; Mock, Donald M; Franco, Robert S; Cohen, Robert M; North, Anne K; Cancelas, José A; Geisen, Christof; Strauss, Ronald G; Vlaar, Alexander P; Nalbant, Demet; Widness, John A

    2017-06-01

    Biotin-labeled red blood cells (BioRBCs) are used for in vivo kinetic studies. Because BioRBC dosing occasionally induces antibodies, a sensitive and specific anti-BioRBC detection assay is needed. Aims were to 1) develop a gel card assay to evaluate existing, naturally occurring and BioRBC-induced plasma antibodies, 2) compare gel card and tube agglutination detection results, and 3) test for a relationship of antibody induction and BioRBC dose. Reagent BioRBCs were prepared using sulfo-NHS biotin ranging from densities 18 (BioRBC-18) to 1458 (BioRBC-1458) µg/mL RBCs. Among BioRBC-exposed subjects, gel card and tube agglutination results were concordant in 21 of 22 adults and all 19 infant plasma samples. Gel card antibody detection sensitivity was more than 10-fold greater than tube agglutination. Twelve to 16 weeks after BioRBC exposure, induced anti-antibodies were detected by gel card in three of 26 adults (12%) at reagent densities BioRBC-256 or less, but in none of 41 infants. Importantly, induced anti-BioRBC antibodies were associated with higher BioRBC dose (p = 0.008); no antibodies were detected in 18 subjects who received BioRBC doses less than or equal to BioRBC-18. For noninduced BioRBC antibodies, six of 1125 naïve adults (0.3%) and none of 46 naïve infants demonstrated existing anti-BioRBC antibodies using reagent BioRBC-140 or -162. Existing anti-BioRBCs were all neutralized by biotin compounds, while induced antibodies were not. The gel card assay is more sensitive than the tube agglutination assay. We recommend reagent BioRBC-256 for identifying anti-BioRBCs. Use of a low total RBC biotin label dose (≤ BioRBC-18) may minimize antibody induction. © 2017 AABB.

  17. HETEROGENETIC ANTIBODIES IN ACUTE HEPATITIS

    PubMed Central

    Eaton, Monroe D.; Murphy, William D.; Hanford, V. Lee

    1944-01-01

    A heterogenetic antibody showing fixation of complement with human liver and agglutination of sheep erythrocytes was found in certain cases of acute infective hepatitis. The antigen concerned in these reactions was apparently heat stable and alcohol soluble. Differences from other heterogenetic antigen-antibody systems have been noted. The possible relation of the heterogenetic antibody to liver damage was considered. PMID:19871386

  18. Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis

    PubMed Central

    Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

    2016-01-01

    Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. PMID:27207442

  19. Latex agglutination using the periplasmic proteins antigen of Brucella melitensis is a successful, rapid, and specific serodiagnostic test for ovine brucellosis.

    PubMed

    Ismael, Alaa Bassuny; Swelum, Ayman Abdel-Aziz; Mostafa, Salama A-H; Alhumiany, Abdel-Rahman A

    2016-09-01

    Brucellosis, especially caused by Brucella melitensis, is considered the most-widespread zoonosis in the world, particularly in developing countries. This study was planned to develop an accurate test for diagnosis of ovine brucellosis using a specific hot saline extracted soluble Brucella melitensis periplasmic proteins (SBPPs). The efficacy of the latex agglutination test (LAT) using SBPPs compared to the Rose Bengal test (RBT), buffered plate agglutination test (BPAT), serum agglutination test (SAT), and an indirect enzyme-linked immunosorbent assay (i-ELISA) was evaluated in the field diagnosis of ovine brucellosis. The test performance was evaluated by estimating sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV), disease prevalence (DP), positive likelihood ratio (PLR), and negative likelihood ratio (NLR) using test agreement and bacteriological culture in 1777 samples. The false-positive result was significantly (P ⩽0.05) lower in LAT than RBT, BPAT, SAT, and i-ELISA. With reference to test agreement, the Se, Sp, PPV, and PLR were highest (P ⩽0.05) in LAT 99.33%, 99.88%, 98.68%, and 827.25%, respectively. With reference to bacteriological culture, the LAT and i-ELISA tests showed a significant difference in Se with SAT. However, no significant difference in specificity was detected. The DP was 8.44% in the five tests. In conclusion, LAT using SBPPs of B. melitensis could be a suitable serodiagnostic field test for ovine brucellosis, with high sensitivity and specificity. © The Author(s) 2016.

  20. Qualitative evaluation of selective tests for detection of Neospora hughesi antibodies in serum and cerebrospinal fluid of experimentally infected horses.

    PubMed

    Packham, Andrea E; Conrad, Patricia A; Wilson, W David; Jeanes, Lisa V; Sverlow, Karen W; Gardner, Ian A; Daft, Barbara M; Marsh, Antoinette E; Blagburn, Byron L; Ferraro, Gregory L; Barr, Bradd C

    2002-12-01

    Neospora hughesi is a newly recognized protozoan pathogen in horses that causes a myeloencephalitis similar to Sarcocystis neurona. There are no validated serologic tests using the gold standard sera that are currently available to detect specific N. hughesi antibodies and, thus, no tests available to detect antemortem exposure or estimate seroprevalence in the horse. The objectives of the present study were to establish a bank of gold standard equine sera through experimental infections with N. hughesi and to assess several serologic tests for the detection of related protozoan antibodies. Seven horses were inoculated with N. hughesi tachyzoites, and 7 horses received uninfected cell culture material. The horses were monitored, and blood and cerebrospinal fluid were collected repeatedly over a 4-mo period. With the sera, 4 different serologic techniques were evaluated. including a whole-parasite lysate enzyme-linked immunosorbent assay (ELISA), a recombinant protein ELISA, a modified direct agglutination test, and an indirect fluorescent antibody test. Qualitative and quantitative evaluation of the results showed that the N. hughesi indirect fluorescent antibody test (IFAT) consistently discriminated between experimentally infected and noninfected horses, using a cutoff of 1:640. Sera from 3 naturally infected horses had titers >1:640. Cerebrospinal fluid in all but I infected horse had very low N. hughesi IFAT titers (<1:160), starting at postinoculation day 30.

  1. Evaluation of a New and Rapid Serologic Test for Detecting Brucellosis: Brucella Coombs Gel Test.

    PubMed

    Hanci, Hayrunisa; Igan, Hakan; Uyanik, Muhammet Hamidullah

    2017-01-01

    Many serological tests have been used for the diagnosis of human brucellosis. A new serological method is identified as Brucella Coombs gel test based on the principle of centrifugation gel system similar to the gel system used in blood group determination. In this system, if Brucella antibodies were present in the serum, antigen and antibody would remain as a pink complex on the gel. Otherwise, the pink Brucella antigens would precipitate at the bottom of the gel card system. In this study, we aimed to compare the Brucella Coombs gel test, a new, rapid screen and titration method for detection of non-agglutinating IgG with the Brucella Coombs test. For this study, a total of 88 serum samples were obtained from 45 healthy persons and 43 individuals who had clinical signs and symptoms of brucellosis. For each specimen, Rose Bengal test, standard agglutination test, Coombs test and Brucella Coombs gel test were carried out. Sensitivity and specificity of Brucella Coombs gel test were found as 100.0 and 82.2%, respectively. Brucella Coombs gel test can be used as a screening test with high sensitivity. By the help of pink Brucella antigen precipitation, the tests' evaluation is simple and objective. In addition, determination of Brucella antibody by rapid titration offers another important advantage.

  2. Conventional Rapid Latex Agglutination in Estimation of von Willebrand Factor: Method Revisited and Potential Clinical Applications

    PubMed Central

    Che Hussin, Che Maraina

    2014-01-01

    Measurement of von Willebrand factor antigen (VWF : Ag) levels is usually performed in a specialised laboratory which limits its application in routine clinical practice. So far, no commercial rapid test kit is available for VWF : Ag estimation. This paper discusses the technical aspect of latex agglutination method which was established to suit the purpose of estimating von Willebrand factor (VWF) levels in the plasma sample. The latex agglutination test can be performed qualitatively and semiquantitatively. Reproducibility, stability, linearity, limit of detection, interference, and method comparison studies were conducted to evaluate the performance of this test. Semiquantitative latex agglutination test was strongly correlated with the reference immunoturbidimetric assay (Spearman's rho = 0.946, P < 0.001, n = 132). A substantial agreement (κ = 0.77) was found between qualitative latex agglutination test and the reference assay. Using the scoring system for the rapid latex test, no agglutination is with 0% VWF : Ag (control negative), 1+ reaction is equivalent to <20% VWF : Ag, and 4+ reaction indicates >150% VWF : Ag (when comparing with immunoturbidimetric assay). The findings from evaluation studies suggest that latex agglutination method is suitable to be used as a rapid test kit for the estimation of VWF : Ag levels in various clinical conditions associated with high levels and low levels of VWF : Ag. PMID:25759835

  3. High prevalance of Toxoplasma Gondii antibodies in domestic pigs in Oaxaca State, Mexico

    USDA-ARS?s Scientific Manuscript database

    Pigs are important in the epidemiology of toxoplasmosis in North America. Seroprevalence of Toxoplasma gondii infection in 525 domestic pigs (337 backyard raised, 188 farm raised) in Oaxaca state, Mexico was determined using the modified agglutination test (MAT, cut off 1:25). Antibodies to T. gondi...

  4. Agglutination of Mouse Erythrocytes by Eperythrozoon coccoides

    PubMed Central

    Iralu, Vichazelhu; Ganong, Kevin D.

    1983-01-01

    Erythrocytes from blood of mice infected with Eperythrozoon coccoides for 3 or 4 days agglutinated spontaneously. Washed E. coccoides particles agglutinated washed erythrocytes of uninfected mice. E. coccoides-mediated agglutination of normal mouse erythrocytes would be an excellent system for studies of bacterial adhesion. Images PMID:6832825

  5. Unique Monoclonal Antibody Recognizing the Third Extracellular Loop of CXCR4 Induces Lymphocyte Agglutination and Enhances Human Immunodeficiency Virus Type 1-Mediated Syncytium Formation and Productive Infection

    PubMed Central

    Tanaka, Reiko; Yoshida, Atsushi; Murakami, Tsutomu; Baba, Eishi; Lichtenfeld, Julliane; Omori, Takeru; Kimura, Tohru; Tsurutani, Naomi; Fujii, Nobutaka; Wang, Zi-Xuan; Peiper, Stephen C.; Yamamoto, Naoki; Tanaka, Yuetsu

    2001-01-01

    To increase insight into the structural basis of CXCR4 utilization in human immunodeficiency virus type 1 (HIV-1) infection, a new generation of three monoclonal antibodies (MAbs) was developed in WKA rats. The A80 MAb, which binds an epitope in the third extracellular loop (ECL3) of CXCR4, has unique biologic properties that provide novel insights into CXCR4 function. This agent enhanced syncytium formation in activated human peripheral blood mononuclear cells (PBMC) infected with X4 or R5 and CEM cells infected with X4 HIV-1 strains. Exposure to A80 increased the productive infection of activated CD4+ T cells and CEM cells with R5 and X4 viruses, respectively. This antibody uniquely induced agglutination of PBMC and CEM cells but did not activate calcium mobilization. Agglutination induced by A80 was inhibited by stromal cell-derived factor 1, T22, and phorbol 12-myristate 13-acetate but was not significantly altered by pretreatment of cells with pertussis toxin, wortmannin, or MAbs to LFA-1, ICAM-1, ICAM-2, and ICAM-3. The binding of the A145 and A120 MAbs was mapped to the N-terminal extracellular domain and a conformational epitope involving ECL1 and ECL2, respectively. Both of these MAbs inhibited HIV-1 infection and lacked the novel properties of A80. These results suggest a new role for CXCR4 in homologous lymphocyte adhesion that is ligand independent and in HIV-1 infection. PMID:11689635

  6. Leptospira and Brucella antibodies in collared anteaters (Tamandua tetradactyla) in Brazilian zoos.

    PubMed

    Sales, Indiara dos Santos; Folly, Márcio Manhães; Garcia, Luize Néli Nunes; Ramos, Tatiane Mendes Varela; da Silva, Mariana Cristina; Pereira, Martha Maria

    2012-12-01

    The presence of Leptospira spp. and Brucella spp. antibodies was investigated in serum samples from 28 collared anteaters (Tamandua tetradactyla) kept in seven Brazilian zoos. Sera were tested against 19 Leptospira serovars using microscopic agglutination. Samples reacted to the following serovars: two (7.14%) to Patoc, three (10.71%) to Tarrasovi, three (10.71%) to both Patoc and Tarrasovi, two (7.14%) to Wolffi, and one (3.57%) to Australis. Two (7.14%) samples reacted to the buffered Brucella antigen test, but no confirmatory reaction occurred using the 2-mercaptoethanol slow slide agglutination test. No sample was reactive in the agar gel immunodiffusion test for rugose species of Brucella. The presence of anti-leptospira agglutinins in captive T. tetradactyla serum indicates that this species may be susceptible to infection by these bacteria.

  7. THE INFLUENCE OF X-RAYS ON THE AGGLUTINATION REACTION IN ANIMALS VACCINATED AGAINST BRUCELLOSIS (in Russian)

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

    Zhidovtsev, V.M.

    1961-08-01

    Tests on rabbits immunized with dry. live brucellosis vaccine and irradiated with 100, 200, and 400 r at the height of agglutination showed a drop in agglutin titer with increased x-ray dose. The higher the dose the faster is the drop n agglutin. (R.V.J.)

  8. Light-scattering analysis of ultrasonic wave's influence on the RBC agglutination in vitro

    NASA Astrophysics Data System (ADS)

    Doubrovski, Valeri A.; Dvoretski, Costanten N.

    1999-04-01

    Elastic light scattering is one of the most often used optical methods to analyze the cells agglutination reaction - the base of a great number of medical diagnostic test and biomedical investigations. The increase of the resolution of methods and apparatus towards the induced cells aggregation - the foundation of the reaction of agglutination, is quite an actual problem. The solution of this problem increases the reliability of the diagnostic test and gives an opportunity to achieve the diagnostic information in the cases when the traditional approaches do not lead to the diagnostic results. The attempt to increase the resolution of the immune reaction analyzer by means of ultrasonic waves action on the reagent mixture in vitro is taken in this paper. The RBC agglutination reaction which is usually used for the blood group type examination is chosen as an example of an object of the investigation. Different laser optical trains of the devices based on the turbidimetric and nephelometric methods and their combination are analyzed here. The influence of the ultrasonic wave time interval action and of the features of the sample preparation procedure on the resolution towards the agglutination process was investigated in this work. It is shown that the ultrasonic wave action on the reagent mixture leads to a large gain in the resolution of the device towards the RBC agglutination process. The experiments showed that the resolution of the device was enough to register the agglutination process even for the erythrocytes with weak agglutination ability when the reaction was invisible without ultrasonic action. It occurred that the diagnostic test time was more than by an order shortened due to the ultrasonic wave action. The optimal ultrasonic time interval action, the sample preparation technology and experimental technique were defined. The principle of the ultrasonic wave action on the cells agglutination process suggested here can be spread out on the immune

  9. A sperm-agglutinating lectin from seeds of Jack fruit (Artocarpus heterophyllus).

    PubMed

    Namjuntra, P; Muanwongyathi, P; Chulavatnatol, M

    1985-04-30

    A lectin specific for N-acetylgalactosamine was isolated from seed extract of Jack fruit (Artocarpus heterophyllus) by ammonium sulfate precipitation, followed by affinity chromatography on a Affigel-galactosamine-agarose column. The lectin possessed agglutinating activities for human and rat sperm as well as human red blood cells. It was found to have Mr = 62,000 consisting of two dissimilar subunits of Mr = 18,000 and 13,000. It also cross-reacted with an antibody against the lectin of Osage Orange (Maclura pomifera).

  10. Agglutination of Trypanosoma cruzi in infected cells treated with serum from chronically infected mice.

    PubMed

    Wendelken, Jennifer L; Rowland, Edwin C

    2009-04-01

    The protozoan parasite Trypanosoma cruzi is the causative agent of Chagas disease. The chronic stage of infection is characterized by a production of neutralizing antibodies in the vertebrate host. A polyclonal antibody, anti-egressin, has been found to inhibit egress of parasites from the host cell late in the intracellular cycle, after the parasites have transformed from the replicative amastigote into the trypomastigote. It has also been found that BALB/c mouse fibroblasts in the late stages of parasite infection become permeable to molecules as large as antibodies, leading to the possibility that anti-egressin affects the intracellular parasites. This project addresses the fate of the intracellular trypomastigotes that have been inhibited from egressing the host cell. Extended cultures of infected fibroblasts treated with chronic mouse serum reduced parasite egress at all time points measured. Parasites released from infected fibroblasts treated with chronic serum had a reduced ability to infect fibroblasts in culture, yet did not lose infectivity entirely. Absorption of chronic serum with living trypomastigotes removed the anti-egressin effect. The possibility that the target of anti-egressin is a parasite surface component is further indicated by the agglutination of extracellular trypomastigotes by chronic serum. The possibility that cross-linking by antibody occurs intracellularly, thus inhibiting egress, was reinforced by cleaving purified IgG into Fab fragments, which did not inhibit egress when added to infected cultures. From this work, it is proposed that the current, best explanation of the mechanism of egress inhibition by anti-egressin is intracellular agglutination, preventing normal parasite-driven egress.

  11. Prevalence of antibodies against Neospora spp. and Sarcocystis neurona in donkeys from northeastern Brazil.

    PubMed

    Gennari, Solange Maria; Pena, Hilda Fátima de Jesus; Lindsay, David Scott; Lopes, Marcos Gomes; Soares, Herbert Sousa; Cabral, Aline Diniz; Vitaliano, Sérgio Netto; Amaku, Marcos

    2016-01-01

    Sarcocystis neurona and Neospora hughesi are coccidian protozoa that can cause neurological illness in horses in America. In this study we report seroprevalence of Neospora spp. andS. neurona in sera of 333 donkeys from the northeastern region of Brazil. Antibodies to Neospora spp. were detected in 2% (7 donkeys) of 333 sera tested by the indirect fluorescent antibody test (IFAT) with a cut-off dilution of 1:40. Antibodies to S. neurona were found in 3% (10 donkeys) of the samples tested by IFAT (cut-off ≥50) and 21% (69 donkeys) by the direct agglutination test (SAT ≥50). The SAT and IFAT results for S. neurona showed a poor concordance (value of Kappa=0.051). This is the first report of Neospora spp. antibodies in Brazilian donkeys and the first detection of antibodies against S. neurona in this animal species.

  12. Seroprevalence of Toxoplasma gondii antibodies in captive wild mammals and birds in Brazil.

    USDA-ARS?s Scientific Manuscript database

    In this study serum samples of 203 animals from different locations from zoos and breeding facilities from the north and northeast region of Brazil were analyzed for the presence of anti-Toxoplasma gondii antibodies by the modified agglutination test (MAT) with a cutoff of 1:25. Of the sampled anima...

  13. Protection against Escherichia coli K1 infection in newborn rats by antibody to K1 capsular polysaccharide antigen.

    PubMed

    Bortolussi, R; Ferrier, P

    1980-04-01

    The protective value of antibody to the K1 capsular polysaccharide antigen of Escherichia coli was investigated in a newborn rat model of E. coli K1 infection. Pregnant rats were immunized intravenously with E. coli, and the agglutinating titer to meningococcal group B polysaccharide, which is identical to K1 polysaccharide, was measured in the serum of rats and their offspring. Convalescent serum from rat mothers showed an increased antibody titer in animals injected twice but not once with E. coli K1. Although no agglutinating antibody was detected in the serum of rat pups, animals suckled by mothers having a meningococcal group B agglutinating titer of 1:8 or greater had reduced infection and mortality rates after intraperitoneal injection with E. coli K1 compared with animals suckled by mothers having a low titer of agglutinating antibody (P less than 0.05). In addition, greater protection could be conferred on rat sucklings by oral supplementation with a horse serum rich in antibody to meningococcal group B polysaccharide, suggesting that antibody was abosorbed from the gastrointestinal tract and by itself could be protective. These studies demonstrated that antibody to the capsular polysaccharide of E. coli K1 altered the severity of E. coli K1 infection. Final clearance of bacteria from the blood appeared to await the maturation of other host defense systems in the newborn rat.

  14. Antibodies to a common outer envelope antigen of Treponema hyodysenteriae with antibacterial activity.

    PubMed

    Sellwood, R; Kent, K A; Burrows, M R; Lysons, R J; Bland, A P

    1989-08-01

    Outer envelopes of Treponema hyodysenteriae strains P18A and VS1 were prepared and characterized by SDS-PAGE. In Western blot analysis of eleven strains of T. hyodysenteriae and two intestinal non-pathogenic spirochaetes, polyclonal antiserum raised to the outer envelopes of strain P18A contained antibodies primarily to two polypeptides. A 45 kDa polypeptide was present in only two strains of T. hyodysenteriae, P18A and MC52/80, whereas another antigen of 16 kDa was common to all eleven strains of T. hyodysenteriae but was not present in the two nonpathogens. Immunogold labelling of whole organisms suggested that the 16 kDa antigen was present on the surface of the spirochaetes. In in vitro tests the serum agglutinated and inhibited growth of only the T. hyodysenteriae strains, suggesting that antibodies to the 16 kDa antigen were responsible for these activities. Serum from a gnotobiotic pig infected with T. hyodysenteriae strain P18A had antibodies to the 16 kDa antigen alone and also possessed agglutinating and growth-inhibitory activities.

  15. Detection of acute childhood meningitis by PCR, culture and agglutination tests in Tabriz, Iran.

    PubMed

    Ghotaslou, Reza; Farajnia, Safar; Yeganeh, Fatemeh; Abdoli-Oskouei, Shahram; Ahangarzadeh Rezaee, Mohammad; Barzegar, Mohammad

    2012-01-01

    Meningitis is one of the hazardous and life threatening infections and is associated with mortality and morbidity. The aim of this study was to determine etiological agents of childhood bacterial meningitis. The culture, Gram staining, agglutination and PCR assays were used to examine CSF specimens from 277 patients with presumed bacterial meningitis for the occurrence of 4 most common infectious agents consist of N. meningitis, H. influnsae, S. pneumoniae and S. agalactiae between 2008 and 2009 at different wards of the Children Hospital of Tabriz. The mean age of patients was 35 ± 2 (Mean ± SEM) month, (minimum 11 days maximum 14 years), of all cases 59.6% male and 40.4% female. Overall the diagnosis was confirmed with a CSF culture in 11/277 (3.97%), by agglutination test in 14/277 (5.05%). The isolated bacteria included S. pneumoniae 5 cases, H. influnsae 2 cases, N. meningitis 3 cases and P. aeroginusae 1 case. A positive PCR assay allowed us to diagnose bacterial meningitis in 19 patients (6.8%). In the present study, we found PCR to be a useful and sensitive method for the detection of bacterial DNA in the CSF samples from suspected meningitis patients. Furthermore, to maximize management of meningitis cases, a combination of culture and PCR is necessary.

  16. Galactosyltransferase and Concanavalin A Agglutination of Cells

    PubMed Central

    Podolsky, Daniel K.; Weiser, Milton M.; Mont, J. Thomas La; Isselbacher, Kurt J.

    1974-01-01

    A correlation has been observed between concanavalin A agglutination of various cell types and the presence of surface membrane galactosyltransferase (1-O-α-D-Galactosyl-myo-inositol:raffinose galactosyltransferase, EC 2.4.1.67) activity. Moreover, a reduction to less than 50% of cell surface galactosyltransferase activity occurred after treatment with concanavalin A; other cell surface glycosyltransferase enzyme activities examined were unaffected by concanavalin A treatment. To confirm the participation of cell surface galactosyltransferase in concanavalin A-induced cell agglutination, the enzyme from rabbit erythrocytes was solubilized by sonication and purified by preparative polyacrylamide gel electrophoresis. It was possible to achieve a purified preparation of rabbit erythrocyte galactosyltransferase by separation on concanavalin A-Sepharose. The purified enzyme showed visible immunoprecipitation (Ouchterlony) with concanavalin A. Furthermore, human erythrocytes, which are not normally agglutinated by concanavalin A, became agglutinable by the lectin when the erythrocytes were preincubated with purified galactosyltransferase. These experiments suggest a direct and possible specific role of cell surface galactosyltransferase enzyme in the mechanism of concanavalin A agglutination of cells. Images PMID:4522801

  17. Anti-insulin antibody test

    MedlinePlus

    Insulin antibodies - serum; Insulin Ab test; Insulin resistance - insulin antibodies; Diabetes - insulin antibodies ... You appear to have an allergic response to insulin Insulin no longer seems to control your diabetes

  18. Validation of serological tests for the detection of antibodies against Treponema pallidum in nonhuman primates.

    PubMed

    Knauf, Sascha; Dahlmann, Franziska; Batamuzi, Emmanuel K; Frischmann, Sieghard; Liu, Hsi

    2015-03-01

    There is evidence to suggest that the yaws bacterium (Treponema pallidum ssp. pertenue) may exist in non-human primate populations residing in regions where yaws is endemic in humans. Especially in light of the fact that the World Health Organizaiton (WHO) recently launched its second yaws eradication campaign, there is a considerable need for reliable tools to identify treponemal infection in our closest relatives, African monkeys and great apes. It was hypothesized that commercially available serological tests detect simian anti-T. pallidum antibody in serum samples of baboons, with comparable sensitivity and specificity to their results on human sera. Test performances of five different treponemal tests (TTs) and two non-treponemal tests (NTTs) were evaluated using serum samples of 57 naturally T. pallidum-infected olive baboons (Papio anubis) from Lake Manyara National Park in Tanzania. The T. pallidum particle agglutination assay (TP-PA) was used as a gold standard for comparison. In addition, the overall infection status of the animals was used to further validate test performances. For most accurate results, only samples that originated from baboons of known infection status, as verified in a previous study by clinical inspection, PCR and immunohistochemistry, were included. All tests, TTs and NTTs, used in this study were able to reliably detect antibodies against T. pallidum in serum samples of infected baboons. The sensitivity of TTs ranged from 97.7-100%, while specificity was between 88.0-100.0%. The two NTTs detected anti-lipoidal antibodies in serum samples of infected baboons with a sensitivity of 83.3% whereas specificity was 100%. For screening purposes, the TT Espline TP provided the highest sensitivity and specificity and at the same time provided the most suitable format for use in the field. The enzyme immune assay Mastblot TP (IgG), however, could be considered as a confirmatory test.

  19. An Alternative Chemical Redox Method for the Production of Bispecific Antibodies: Implication in Rapid Detection of Food Borne Pathogens

    PubMed Central

    Owais, Mohammad; Kazmi, Shadab; Tufail, Saba; Zubair, Swaleha

    2014-01-01

    Bi-functional antibodies with the ability to bind two unrelated epitopes have remarkable potential in diagnostic and bio-sensing applications. In the present study, bispecific antibodies that recognize human red blood cell (RBC) and the food borne pathogen Listeria monocytogenes (L. monocytogenes) were engineered. The procedure involves initial reduction of a mixture of anti-RBC and anti-Listeria antibodies followed by gradual re-oxidation of the reduced disulphides. This facilitates association of the separated antibody chains and formation of hybrid immunoglobulins with affinity for the L. monocytogenes and human RBC. The bispecific antibodies caused the agglutination of the RBCs only in the presence of L. monocytogenes cells. The agglutination process necessitated the specific presence of L. monocytogenes and the red colored clumps formed were readily visible with naked eyes. The RBC agglutination assay described here provides a remarkably simple approach for the rapid and highly specific screening of various pathogens in their biological niches. PMID:24637674

  20. The Rapid Diagnosis of Leptospirosis: A Prospective Comparison of the Dot Enzyme-Linked Immunosorbent Assay and the Genus-Specific Microscopic Agglutination Test at Different Stages of Illness

    DTIC Science & Technology

    1988-04-01

    stages of illness. 12 09RSONAL AU’THORt(S) George WttT4y M . Aiquiza, Laurei P. Padre, Ma. Linda Tuazon, Lar,:y- W. awbi 13s. TYPE OF REPORT I ]b TIME...agglutination test at different stages of illness George Watt, Lily M , Alquiza, Laurena Padre, Ma. Linda Tuazon, and Larry W. Laughlin REPORT NO. TR...MICROSCOPIC AGGLUTINATION TEST AT DIFFERENT STAGES OF ILLNESS GLORGE WATT. LILY M . ALQUIZA, LAURENA P. PADRE. MAR! • LINDA TAUZON, and LARRY W

  1. [Isolation and immunology identification of spermagglutinating antibodies from human serum].

    PubMed

    Cibulka, J; Ulcova-Gallová, Z; Balvín, M; Bibková, K; Micanová, Z

    2009-06-01

    Isolation of spermagglutinating antibodies and their assesment. Retrospective study. Special consulting for reptoduction immunology, Department of Obstetrics and Gynecology, Charles University and Faculty Hospital, Plzen. Fractionation of serum samples by liquid exclusion chromatography, examination of full sera and their chromatographic fractions by Friberg teste (Tray Agglutination Test--TAT), indirect antiimmunoglobulin reaction test (i-MAR test) and by supplementar radial immunodiffusiona (RID). Isolation of spermagglutinating fractions of antisperm antibodies positive sera preserved spermagglutinating aktivity and confirmed great spermagglutinating potential of IgM. According to assesment of the presence of IgG and IgG we reported possible states of immunisation: actual immunisation with IgM activity, perpetual stimulation (IgG and IgM) and, finaly, anamnestic titres in IgG. These findings can help us to choose an optimal way of treatment. Excluding gel chromatography is suitable method for serum proteins fractionation, but not their identification--presence of antisperm antibodies does not affect the chromatographic spectrum, nor the RID patterns.

  2. Bayesian estimation of sensitivity and specificity of the modified agglutination test and bioassay for detection of Toxoplasma gondii in free-range chickens

    USDA-ARS?s Scientific Manuscript database

    Toxoplasma gondii infects virtually all warm-blooded animals worldwide. Serological tests, including the modified agglutination test (MAT), are often used to determine exposure to the parasite. The MAT can be used for all hosts because it does not need species-specific reagents and has been shown to...

  3. Baseline Antibody Titre against Salmonella enterica in Healthy Population of Mumbai, Maharashtra, India.

    PubMed

    Patki, Rucha; Lilani, Sunil; Lanjewar, Dhaneshwar

    2017-01-01

    The aim of this study was to establish a baseline titre for the population of Mumbai, Maharashtra, India. Four hundred healthy blood donors, attending blood donation camps, were screened using a survey questionnaire. Widal tube agglutination test was performed on the diluted sera (with 0.9% normal saline) of blood donors, with final dilution ranging from 1 : 40 to 1 : 320. Out of 400 individuals providing samples, 78 (19.5%) individuals showed antibody titres ≥ 1 : 40 for at least one antigen and 322 (80.5%) showed no agglutination. The baseline antibody titres against O antigen and H antigen of Salmonella enterica serotype Typhi were found to be 1 : 40 and 1 : 80, respectively. Similarly, the baseline antibody titres for the H antigen of Salmonella enterica serotypes Paratyphi A and Paratyphi B were found to be 1 : 40 and 1 : 80, respectively. Thus, it was noted that the diagnostically significant cutoff of antibody titre from acute phase sample was ≥ 1 : 80 for S. Typhi O antigen and titre of ≥ 1 : 160 for both S. Typhi H antigen and S. Paratyphi BH antigen. Antibody titre of ≥ 1 : 80 can be considered significant for S. Paratyphi AH antigen.

  4. Baseline Antibody Titre against Salmonella enterica in Healthy Population of Mumbai, Maharashtra, India

    PubMed Central

    Lilani, Sunil; Lanjewar, Dhaneshwar

    2017-01-01

    Objective The aim of this study was to establish a baseline titre for the population of Mumbai, Maharashtra, India. Method Four hundred healthy blood donors, attending blood donation camps, were screened using a survey questionnaire. Widal tube agglutination test was performed on the diluted sera (with 0.9% normal saline) of blood donors, with final dilution ranging from 1 : 40 to 1 : 320. Results Out of 400 individuals providing samples, 78 (19.5%) individuals showed antibody titres ≥ 1 : 40 for at least one antigen and 322 (80.5%) showed no agglutination. The baseline antibody titres against O antigen and H antigen of Salmonella enterica serotype Typhi were found to be 1 : 40 and 1 : 80, respectively. Similarly, the baseline antibody titres for the H antigen of Salmonella enterica serotypes Paratyphi A and Paratyphi B were found to be 1 : 40 and 1 : 80, respectively. Conclusion Thus, it was noted that the diagnostically significant cutoff of antibody titre from acute phase sample was ≥ 1 : 80 for S. Typhi O antigen and titre of ≥ 1 : 160 for both S. Typhi H antigen and S. Paratyphi BH antigen. Antibody titre of ≥ 1 : 80 can be considered significant for S. Paratyphi AH antigen. PMID:29081804

  5. ANA (Antinuclear Antibody) Test: MedlinePlus Lab Test Information

    MedlinePlus

    ... medlineplus.gov/labtests/anaantinuclearantibodytest.html ANA (Antinuclear Antibody) Test To use the sharing features on this page, ... enable JavaScript. What is an ANA (Antinuclear Antibody) Test? An ANA test looks for antinuclear antibodies in ...

  6. A low cost and high throughput magnetic bead-based immuno-agglutination assay in confined droplets.

    PubMed

    Teste, Bruno; Ali-Cherif, Anaïs; Viovy, Jean Louis; Malaquin, Laurent

    2013-06-21

    Although passive immuno-agglutination assays consist of one step and simple procedures, they are usually not adapted for high throughput analyses and they require expensive and bulky equipment for quantitation steps. Here we demonstrate a low cost, multimodal and high throughput immuno-agglutination assay that relies on a combination of magnetic beads (MBs), droplets microfluidics and magnetic tweezers. Antibody coated MBs were used as a capture support in the homogeneous phase. Following the immune interaction, water in oil droplets containing MBs and analytes were generated and transported in Teflon tubing. When passing in between magnetic tweezers, the MBs contained in the droplets were magnetically confined in order to enhance the agglutination rate and kinetics. When releasing the magnetic field, the internal recirculation flows in the droplet induce shear forces that favor MBs redispersion. In the presence of the analyte, the system preserves specific interactions and MBs stay in the aggregated state while in the case of a non-specific analyte, redispersion of particles occurs. The analyte quantitation procedure relies on the MBs redispersion rate within the droplet. The influence of different parameters such as magnetic field intensity, flow rate and MBs concentration on the agglutination performances have been investigated and optimized. Although the immuno-agglutination assay described in this work may not compete with enzyme linked immunosorbent assay (ELISA) in terms of sensitivity, it offers major advantages regarding the reagents consumption (analysis is performed in sub microliter droplet) and the platform cost that yields to very cheap analyses. Moreover the fully automated analysis procedure provides reproducible analyses with throughput well above those of existing technologies. We demonstrated the detection of biotinylated phosphatase alkaline in 100 nL sample volumes with an analysis rate of 300 assays per hour and a limit of detection of 100 pM.

  7. Prevalence of antibodies against Leptospira sp. in snakes, lizards and turtles in Slovenia

    PubMed Central

    2013-01-01

    Background Leptospiral infections in poikilothermic (cold blooded) animals have received very little attention and the literature concerning natural infections of these animals is limited. The aim of this study was to determine the prevalence of leptospiral antibodies in reptiles, imported into Slovenia and intended to be pets in close contact with humans. A total of 297 reptiles (22 snakes, 210 lizards and 65 turtles) were tested for specific antibodies against serovars of Leptospira interrogans sensu stricto using the microscopic agglutination test (MAT). Live cultures of different serovars were used as antigens. MAT was performed according to standard procedures and the degree of reaction was interpreted by estimating the percentage of agglutinated leptospires. Samples showing titres of ≥ 50 against one or more serovars were considered as positive. Results Antibodies against seven pathogenic serovars of L. interrogans sensu stricto were detected in 46 of 297 reptiles. Among 22 snakes, specific antibodies against pathogenic serovars of three Leptospira species (L. interrogans, L. kirschneri and L. borgpetersenii) at titre levels from 1:50 to 1:400 were detected in 6 snakes. In 31 of 210 lizards, specific antibodies were found in titres from 1:50 to 1:1000 and, finally, among 65 turtles (terrapins and tortoises), 9 had specific antibodies at titre levels between 1:50 and 1:1600. Animals imported from non-EU countries showed significantly higher prevalence (25.0%; 95 confidence interval: 16.7–33.3%) than animals from EU member states (10.4%; confidence interval: 6.1–14.7%). Conclusions Reptiles may be considered as potential reservoirs of L. interrogans sensu stricto. Origin of the animals is a risk factor for presence of leptospiral antibodies, especially in lizards. Special attention should be focused on animals from non-EU member states. PMID:24020619

  8. A novel tool for high-throughput screening of granulocyte-specific antibodies using the automated flow cytometric granulocyte immunofluorescence test (Flow-GIFT).

    PubMed

    Nguyen, Xuan Duc; Dengler, Thomas; Schulz-Linkholt, Monika; Klüter, Harald

    2011-02-03

    Transfusion-related acute lung injury (TRALI) is a severe complication related with blood transfusion. TRALI has usually been associated with antibodies against leukocytes. The flow cytometric granulocyte immunofluorescence test (Flow-GIFT) has been introduced for routine use when investigating patients and healthy blood donors. Here we describe a novel tool in the automation of the Flow-GIFT that enables a rapid screening of blood donations. We analyzed 440 sera from healthy female blood donors for the presence of granulocyte antibodies. As positive controls, 12 sera with known antibodies against anti-HNA-1a, -b, -2a; and -3a were additionally investigated. Whole-blood samples from HNA-typed donors were collected and the test cells isolated using cell sedimentation in a Ficoll density gradient. Subsequently, leukocytes were incubated with the respective serum and binding of antibodies was detected using FITC-conjugated antihuman antibody. 7-AAD was used to exclude dead cells. Pipetting steps were automated using the Biomek NXp Multichannel Automation Workstation. All samples were prepared in the 96-deep well plates and analyzed by flow cytometry. The standard granulocyte immunofluorescence test (GIFT) and granulocyte agglutination test (GAT) were also performed as reference methods. Sixteen sera were positive in the automated Flow-GIFT, while five of these sera were negative in the standard GIFT (anti-HNA 3a, n = 3; anti-HNA-1b, n = 1) and GAT (anti-HNA-2a, n = 1). The automated Flow-GIFT was able to detect all granulocyte antibodies, which could be only detected in GIFT in combination with GAT. In serial dilution tests, the automated Flow-GIFT detected the antibodies at higher dilutions than the reference methods GIFT and GAT. The Flow-GIFT proved to be feasible for automation. This novel high-throughput system allows an effective antigranulocyte antibody detection in a large donor population in order to prevent TRALI due to transfusion of blood products.

  9. Evaluation of Four Bedside Test Systems for Card Performance, Handling and Safety.

    PubMed

    Giebel, Felix; Picker, Susanne M; Gathof, Birgit S

    2008-01-01

    SUMMARY: OBJECTIVE: Pretransfusion ABO compatibility testing is a simple and required precaution against ABO-incompatible transfusion, which is one of the greatest threats in transfusion medicine. While distinct agglutination is most important for correct test interpretation, protection against infectious diseases and ease of handling are crucial for accurate test performance. Therefore, the aim of this study was to evaluate differences in test card design, handling, and user safety. DESIGN: Four different bedside test cards with pre-applied antibodies were evaluated by 100 medical students using packed red blood cells of different ABO blood groups. Criteria of evaluation were: agglutination, labelling, handling, and safety regarding possible user injuries. Criteria were rated subjectively according to German school notes ranging from 1 = very good to 6 = very bad/insufficient. RESULTS: Overall, all cards received very good/good marks. The ABO blood group was identified correctly in all cases. Three cards (no. 1, no. 3, no. 4) received statistically significant (p < 0.008) prominence (mean values shown) concerning clearness of agglutination (1.7-1.9 vs. 2.4 for no. 2). Systems with dried antibodies (no. 2, no. 4) outmatched the other systems with respect to overall test system performance (2.0 vs. 2.8-2.9), labelling (1.5 vs. 2.2-2.4), handling (1.9-2.0 vs. 2.5), and user safety (2.5 vs. 3.4). Analysis of card self-explanation revealed no remarkable differences. CONCLUSION: Despite good performance of all card systems tested, the best results when including all criteria evaluated were obtained with card no. 4 (particularly concerning clear agglutination), followed by cards no. 2, no. 1, and no. 3.

  10. Construction of an agglutination tool: recombinant Fab fragments biotinylated in vitro.

    PubMed

    Czerwinski, Marcin; Krop-Watorek, Anna; Wasniowska, Kazimiera; Smolarek, Dorota; Spitalnik, Steven L

    2009-11-30

    The pComb3H vector system is used for constructing and panning recombinant antibody libraries. It allows for expression of monovalent Fab fragments, either on the surface of M13 phage, or in the form of soluble proteins secreted into the periplasmic space of bacteria. We constructed a modified pComb3H vector containing cDNA encoding for a 23-amino acid fragment of the Escherichia coli biotin carboxy carrier protein (BCCP), which is an acceptor sequence for biotinylation. The vector was used to express the Fab fragment recognizing human glycophorin A. The purified Fab fragment containing this biotin acceptor sequence was effectively biotinylated in vitro using biotin ligase (BirA). The specificity and avidity of the biotinylated Fab fragments were similar to the previously produced, unmodified Fab fragments. An avidin-alkaline phosphatase conjugate was used to detect the recombinant Fab fragments, instead of secondary antibody. In addition, when biotinylated Fab fragments were mixed with avidin, red blood cells were directly agglutinated.

  11. Red Blood Cell Agglutination for Blood Typing Within Passive Microfluidic Biochips.

    PubMed

    Huet, Maxime; Cubizolles, Myriam; Buhot, Arnaud

    2018-04-19

    Pre-transfusion bedside compatibility test is mandatory to check that the donor and the recipient present compatible groups before any transfusion is performed. Although blood typing devices are present on the market, they still suffer from various drawbacks, like results that are based on naked-eye observation or difficulties in blood handling and process automation. In this study, we addressed the development of a red blood cells (RBC) agglutination assay for point-of-care blood typing. An injection molded microfluidic chip that is designed to enhance capillary flow contained anti-A or anti-B dried reagents inside its microchannel. The only blood handling step in the assay protocol consisted in the deposit of a blood drop at the tip of the biochip, and imaging was then achieved. The embedded reagents were able to trigger RBC agglutination in situ, allowing for us to monitor in real time the whole process. An image processing algorithm was developed on diluted bloods to compute real-time agglutination indicator and was further validated on undiluted blood. Through this proof of concept, we achieved efficient, automated, real time, and quantitative measurement of agglutination inside a passive biochip for blood typing which could be further generalized to blood biomarker detection and quantification.

  12. Antiparietal cell antibody test

    MedlinePlus

    ... Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; Vitamin B12 - anti- ... may use this test to help diagnose pernicious anemia. Pernicious anemia is a decrease in red blood ...

  13. RSV antibody test

    MedlinePlus

    Respiratory syncytial virus antibody test; RSV serology; Bronchiolitis - RSV test ... Crowe JE. Respiratory syncytial virus. In: Kliegman RM, Stanton BF, St. Geme JW, Schor NF, eds. Nelson Textbook of Pediatrics . 20th ...

  14. Evaluation of latex agglutination test (KAtex) for early diagnosis of kala-azar.

    PubMed

    Ahsan, M M; Islam, M N; Mollah, A H; Hoque, M A; Hossain, M A; Begum, Z; Islam, M T

    2010-07-01

    Kala-azar is one of the major public health problem in Bangladesh. But the diagnosis of the problem often is difficult, unusual and time consuming, a simple, noninvasive, easy to perform, reliable and rapid diagnostic test has been a long-felt need of the clinicians. Therefore, the present study was conducted to see the sensitivity and specificity of Latex Agglutination test (KAtex) to detect leishmanial antigen from urine of kala-azar cases. The study was carried out in the department of Paediatrics, Mymensingh Medical College and Hospital, Bangladesh during July to December, 2008. A total of 100 urine samples were collected of which 50 were confirmed kala-azar cases and 50 were age and sex matched controls. Out of 50 kala-azar cases 47 showed positive result of KAtex. The test was also positive in 01 out of 30 healthy controls. None of the febrile controls was positive by KAtex. The sensitivity, specificity, positive predictive value and negative predictive value of the test using presence of LD bodies in splenic and/or bone marrow aspirate as gold standard were 94%, 98%, 97.91% and 94.23% respectively. KAtex is simple, noninvasive, easy to perform, rapid and reliable test for diagnosing kala-azar in endemic area and useful for small, less equipped laboratories as well as for the laboratories with better facilities.

  15. A critical role for the regulation of Syk from agglutination to aggregation in human platelets.

    PubMed

    Shih, Chun-Ho; Chiang, Tin-Bin; Wang, Wen-Jeng

    2014-01-10

    Agglucetin, a tetrameric glycoprotein (GP) Ibα agonist from Formosan Agkistrodon acutus venom, has been characterized as an agglutination inducer in human washed platelets (WPs). In platelet-rich plasma (PRP), agglucetin dramatically elicits a biphasic response of agglutination and subsequent aggregation. For clarifying the intracellular signaling events from agglutination to aggregation in human platelets, we examined the essential signaling molecules involved through the detection of protein tyrosine phosphorylation (PTP). In WPs, an anti-GPIbα monoclonal antibody (mAb) AP1, but not a Src kinase inhibitor PP1, completely inhibited agglucetin-induced agglutination. However, PP1 but not AP1 had a potent suppression on platelet aggregation by a GPVI activator convulxin. The PTP analyses showed agglucetin alone can cause a weak pattern involving sequential phosphorylation of Lyn/Fyn, Syk, SLP-76 and phospholipase Cγ2 (PLCγ2). Furthermore, a Syk-selective kinase inhibitor, piceatannol, significantly suppressed the aggregating response in agglucetin-activated PRP. Analyzed by flow cytometry, the binding capacity of fluorophore-conjugated PAC-1, a mAb recognizing activated integrin αIIbβ3, was shown to increase in agglucetin-stimulated platelets. Again, piceatannol but not PP1 had a concentration-dependent suppression on agglucetin-induced αIIbβ3 exposure. Moreover, the formation of signalosome, including Syk, SLP-76, VAV, adhesion and degranulation promoting adapter protein (ADAP) and PLCγ2, are required for platelet aggregation in agglucetin/fibrinogen-activated platelets. In addition, GPIbα-ligation via agglucetin can substantially promote the interactions between αIIbβ3 and fibrinogen. Therefore, the signal pathway of Lyn/Fyn/Syk/SLP-76/ADAP/VAV/PLCγ2/PKC is sufficient to trigger platelet aggregation in agglucetin/fibrinogen-pretreated platelets. Importantly, Syk may function as a major regulator for the response from GPIbα-initiated agglutination to

  16. Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A

    PubMed Central

    Chen, Alex; McKinley, Scott A.; Shi, Feng; Wang, Simi; Mucha, Peter J.; Harit, Dimple; Forest, M. Gregory; Lai, Samuel K.

    2015-01-01

    Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of “immune exclusion” based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers–a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates. PMID:26132216

  17. Anti-H antibody of unusually high titer showing variable reactivities against group A red cells and broad thermal amplitude in a patient with lymphoma.

    PubMed

    Choi, Seung Jun; Kim, Hoon Seok; Lee, Jaewoong; Song, Young-Sun; Lim, Jihyang

    2018-02-01

    We report a case of a patient with high titer anti-H antibody showing broad thermal amplitude and variable reactivities against group A red cells. A 62-year-old Korean female was diagnosed with diffuse large B cell lymphoma involving multiple organs. Her ABO/RhD type was A+ and her genotype was ABO*A.01.01/ABO*O.01.02. Antibody screening test (AST) and antibody identification test (IDT) were strongly positive for all reagent cells. Anti-human globulin (AHG) test revealed an antibody titer of 1:256 for 37 °C phase and trace positivity for poly- and mono-specific C3d. Reactivity was stronger for O+ red cells than that for A+ red cells across all temperatures tested (4 °C, room temperature (RT) and 37 °C). This was also found for AHG phase. Anti-IH was ruled out based on agglutination of O+ cord cells (CCs). Antibody was determined as IgM anti-H after DTT treatment. Three batches of 10 A+ red cells from random donors were tested with three consecutive serums for crossmatching using tube method. Interestingly, out of thirty A+ red cells tested, 20 cells at RT, 11 cells at 37 °C and 11 cells in the AHG phase showed reactivity of greater than 2+. The patient was transfused with 6 units of packed RBCs subsequently. Chemotherapy (R-CHOP regimen) and Helicobacter pylori eradication were then started. Her antibody titer gradually decreased following such treatment. In conclusion, we identified a case of patient with high titer anti-H with broad thermal amplitude, suggesting that anti-H antibodies might need to be considered for cases with pan-agglutination in AST and IDT. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. The value of automated gel column agglutination technology in the identification of true inherited D blood types in massively transfused patients.

    PubMed

    Summers, Thomas; Johnson, Viviana V; Stephan, John P; Johnson, Gloria J; Leonard, George

    2009-08-01

    Massive transfusion of D- trauma patients in the combat setting involves the use of D+ red blood cells (RBCs) or whole blood along with suboptimal pretransfusion test result documentation. This presents challenges to the transfusion service of tertiary care military hospitals who ultimately receive these casualties because initial D typing results may only reflect the transfused RBCs. After patients are stabilized, mixed-field reaction results on D typing indicate the patient's true inherited D phenotype. This case series illustrates the utility of automated gel column agglutination in detecting mixed-field reactions in these patients. The transfusion service test results, including the automated gel column agglutination D typing results, of four massively transfused D- patients transfused D+ RBCs is presented. To test the sensitivity of the automated gel column agglutination method in detecting mixed-field agglutination reactions, a comparative analysis of three automated technologies using predetermined mixtures of D+ and D- RBCs is also presented. The automated gel column agglutination method detected mixed-field agglutination in D typing in all four patients and in the three prepared control specimens. The automated microwell tube method identified one of the three prepared control specimens as indeterminate, which was subsequently manually confirmed as a mixed-field reaction. The automated solid-phase method was unable to detect any mixed fields. The automated gel column agglutination method provides a sensitive means for detecting mixed-field agglutination reactions in the determination of the true inherited D phenotype of combat casualties transfused massive amounts of D+ RBCs.

  19. A Protein-Conjugate Approach to Develop a Monoclonal Antibody-Based Antigen Detection Test for the Diagnosis of Human Brucellosis

    PubMed Central

    Patra, Kailash P.; Saito, Mayuko; Atluri, Vidya L.; Rolán, Hortensia G.; Young, Briana; Kerrinnes, Tobias; Smits, Henk; Ricaldi, Jessica N.; Gotuzzo, Eduardo; Gilman, Robert H.; Tsolis, Renee M.; Vinetz, Joseph M.

    2014-01-01

    Human brucellosis is most commonly diagnosed by serology based on agglutination of fixed Brucella abortus as antigen. Nucleic acid amplification techniques have not proven capable of reproducibly and sensitively demonstrating the presence of Brucella DNA in clinical specimens. We sought to optimize a monoclonal antibody-based assay to detect Brucella melitensis lipopolysaccharide in blood by conjugating B. melitensis LPS to keyhole limpet hemocyanin, an immunogenic protein carrier to maximize IgG affinity of monoclonal antibodies. A panel of specific of monoclonal antibodies was obtained that recognized both B. melitensis and B. abortus lipopolysaccharide epitopes. An antigen capture assay was developed that detected B. melitensis in the blood of experimentally infected mice and, in a pilot study, in naturally infected Peruvian subjects. As a proof of principle, a majority (7/10) of the patients with positive blood cultures had B. melitensis lipopolysaccharide detected in the initial blood specimen obtained. One of 10 patients with relapsed brucellosis and negative blood culture had a positive serum antigen test. No seronegative/blood culture negative patients had a positive serum antigen test. Analysis of the pair of monoclonal antibodies (2D1, 2E8) used in the capture ELISA for potential cross-reactivity in the detection of lipopolysaccharides of E. coli O157:H7 and Yersinia enterocolitica O9 showed specificity for Brucella lipopolysaccharide. This new approach to develop antigen-detection monoclonal antibodies against a T cell-independent polysaccharide antigen based on immunogenic protein conjugation may lead to the production of improved rapid point-of-care-deployable assays for the diagnosis of brucellosis and other infectious diseases. PMID:24901521

  20. Multiple Diphtheria Antigen-Antibody Systems Investigated by Passive Haemagglutination Techniques and Other Methods

    PubMed Central

    Fulthorpe, A. J.

    1962-01-01

    A fair degree of correlation has been found between the in vivo antitoxin content of sera from horses immunized with crude Corynebacterium diphtheriae culture filtrates and the direct agglutinin titre of the sera when tested with sheep cells sensitized with diphtheria toxoid. Haemagglutination inhibition tests at the LA level of test with the same sera showed some rather large discrepancies from the in vivo and further tests with special agglutinin inhibiting toxins suggested that specific antitoxin free from other accessory antibodies might be non-agglutinating, and therefore not titratable by haemagglutination inhibition. The phosphate-stable, pepsin-stable and trypsin-stable antigens isolated from culture filtrates of C. diphtheriae were found to contain extremely small quantities of specific toxoid, and cross titration of each of the three antigen preparations showed that there was very little contamination by other antigens within the group. Absorption of diphtheria antiserum with red cells sensitized with each of the three accessory antigens individually, showed that the antibodies were highly specific and distinct. Absorption of diphtheria antiserum with a mixture of red cells sensitized with the three different antigens removed all demonstrable accessory antibodies, and the absorbed serum would no longer agglutinate cells sensitized with complete diphtheria toxoid. The absorbed serum, however, retained a large proportion of its neutralizing capacity for diphtheria toxin, when titrated in vivo. Titration of each of the accessory antibodies in a number of horse sera by haemagglutination inhibition demonstrated a correlation between the values for the accessory antibodies to the phosphate-stable and pepsin-stable antigens, but no correlation with the values for the antibody to the trypsin-stable antigen, when compared with results of the flocculation test. The relative proportions of diphtheria toxin and of the phosphate-stable and pepsin-stable antigens

  1. 21 CFR 660.54 - Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... heterospecific antibodies, and additional tests for nonspecific properties. 660.54 Section 660.54 Food and Drugs..., specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. The...) Specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. [50...

  2. Measurement of RBC agglutination with microscopic cell image analysis in a microchannel chip.

    PubMed

    Cho, Chi Hyun; Kim, Ju Yeon; Nyeck, Agnes E; Lim, Chae Seung; Hur, Dae Sung; Chung, Chanil; Chang, Jun Keun; An, Seong Soo A; Shin, Sehyun

    2014-01-01

    Since Landsteiner's discovery of ABO blood groups, RBC agglutination has been one of the most important immunohematologic techniques for ABO and RhD blood groupings. The conventional RBC agglutination grading system for RhD blood typings relies on macroscopic reading, followed by the assignment of a grade ranging from (-) to (4+) to the degree of red blood cells clumping. However, with the new scoring method introduced in this report, microscopically captured cell images of agglutinated RBCs, placed in a microchannel chip, are used for analysis. Indeed, the cell images' pixel number first allows the differentiation of agglutinated and non-agglutinated red blood cells. Finally, the ratio of agglutinated RBCs per total RBC counts (CRAT) from 90 captured images is then calculated. During the trial, it was observed that the agglutinated group's CRAT was significantly higher (3.77-0.003) than that of the normal control (0). Based on these facts, it was established that the microchannel method was more suitable for the discrimination between agglutinated RBCs and non-agglutinated RhD negative, and thus more reliable for the grading of RBCs agglutination than the conventional method.

  3. Detection of antibodies against Sarcocystis neurona, Neospora spp., and Toxoplasma gondii in horses from Costa Rica.

    PubMed

    Dangoudoubiyam, S; Oliveira, J B; Víquez, C; Gómez-García, A; González, O; Romero, J J; Kwok, O C H; Dubey, J P; Howe, D K

    2011-06-01

    Serum samples from 315 horses from Costa Rica, Central America, were examined for the presence of antibodies against Sarcocystis neurona, Neospora spp., and Toxoplasma gondii by using the surface antigen (SAG) SnSAG2 enzyme-linked immunosorbent assay (ELISA), the NhSAG1 ELISA, and the modified agglutination test, respectively. Anti- S. neurona antibodies were found in 42.2% of the horses by using the SnSAG2 ELISA. Anti- Neospora spp. antibodies were found in only 3.5% of the horses by using the NhSAG1 ELISA, and only 1 of these horses was confirmed seropositive by Western blot. Antibodies to T. gondii were found in 34.0% of the horses tested, which is higher than in previous reports from North and South America. The finding of anti- S. neurona antibodies in horses from geographical areas where Didelphis marsupialis has wide distribution suggests that D. marsupialis is a potential definitive host for this parasite and a source of infection for these horses.

  4. Red blood cell membrane viscoelasticity, agglutination and zeta potential measurements with double optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Fernandes, Heloise P.; Barjas-Castro, Maria L.; de Thomaz, André A.; de Ysasa Pozzo, Liliana; Barbosa, Luiz C.; Cesar, Carlos L.

    2006-02-01

    The red blood cell (RBC) viscoelastic membrane contains proteins and glycolproteins embedded in, or attached, to a fluid lipid bilayer and are negatively charged, which creates a repulsive electric (zeta) potential between the cells and prevents their aggregation in the blood stream. There are techniques, however, to decrease the zeta potential to allow cell agglutination which are the basis of most of the tests of antigen-antibody interactions in blood banks. This report shows the use of a double optical tweezers to measure RBC membrane viscosity, agglutination and zeta potential. In our technique one of the optical tweezers trap a silica bead that binds strongly to a RBC at the end of a RBCs rouleaux and, at the same time, acts as a pico-Newton force transducer, after calibration through its displacement from the equilibrium position. The other optical tweezers trap the RBC at the other end. To measure the membrane viscosity the optical force is measured as a function of the velocity between the RBCs. To measure the adhesion the tweezers are slowly displaced apart until the RBCs disagglutination happens. The RBC zeta potential is measured in two complimentary ways, by the force on the silica bead attached to a single RBC in response to an applied electric field, and the conventional way, by the measurement of terminal velocity of the RBC after released from the optical trap. These two measurements provide information about the RBC charges and, also, electrolytic solution properties. We believe this can improve the methods of diagnosis in blood banks.

  5. Long-term human serum antibody responses after immunization with whole-cell pertussis vaccine in France.

    PubMed Central

    Grimprel, E; Bégué, P; Anjak, I; Njamkepo, E; François, P; Guiso, N

    1996-01-01

    Three hundred sixty children were tested for pertussis serology 0.5 to 1.58 months after complete whole-cell pertussis vaccination. An immunoblot assay was used to detect serum antibodies to pertussis toxin, filamentous hemagglutinin, adenylate cyclase-hemolysin, and pertactin, and agglutination was used for detection of anti-agglutinogen antibodies. Antibodies against pertussis toxin, pertactin, and agglutinogens decreased rapidly after vaccination but increased secondarily, suggesting exposure to infected persons. In contrast, anti-filamentous hemagglutinin antibodies persisted and anti-adenylate cyclase-hemolysin antibodies increased continuously, suggesting either cross-reaction with non-Bordetella antigens or exposure to Bordetella isolates expressing these two antigens, including Bordetella pertussis. These data suggest that unrecognized pertussis is common in France despite massive and sustained immunization in infants and that vaccinated children become susceptible to infection more than 6 years after their last vaccination. PMID:8770511

  6. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozoon cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossums, Didelphis virginiana, from southern Louisiana.

    PubMed

    Houk, Alice E; Goodwin, David G; Zajac, Anne M; Barr, Stephen C; Dubey, J P; Lindsay, David S

    2010-12-01

    We examined the prevalence of antibodies to zoonotic protozoan parasites ( Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoans of veterinary importance ( Neospora caninum, Sarcocystis neurona, and Besnoitia darlingi) in a population of North American opossums ( Didelphis virginiana) from Louisiana. Samples from 30 opossums were collected as part of a survey for T. cruzi in Louisiana. Frozen sera from these 30 opossums were examined using an indirect immunofluorescent antibody test (IFAT) against in vitro-produced antigenic stages of these protozoans. Additionally, 24 of the 30 samples were examined using hemoculture, and all 30 were examined in the modified direct agglutination test (MAT) for antibodies to To. gondii. The prevalences of reactive IFAT samples were as follows: 60% for T. cruzi, 27% for To. gondii, 23% for E. cuniculi, 17% for S. neurona, 47% for B. darlingi, and 0% for N. caninum. Hemoculture revealed that 16 (67%) of 24 samples were positive for T. cruzi, compared to 18 of 30 (60%) by IFAT. The sensitivity and specificity for the IFAT compared to hemoculture was 100% for each. The modified direct agglutination test revealed that 9 (30%) of the 30 samples from opossums had antibodies to To. gondii , compared to 8 (27%) using the IFAT. The sensitivity and specificity of the IFAT compared to the MAT was 100% and 72%, respectively.

  7. Utility of feline coronavirus antibody tests.

    PubMed

    Addie, Diane D; le Poder, Sophie; Burr, Paul; Decaro, Nicola; Graham, Elizabeth; Hofmann-Lehmann, Regina; Jarrett, Oswald; McDonald, Michael; Meli, Marina L

    2015-02-01

    Eight different tests for antibodies to feline coronavirus (FCoV) were evaluated for attributes that are important in situations in veterinary practice. We compared four indirect immunofluorescent antibody tests (IFAT), one enzyme-linked immunosorbent assay (ELISA) (FCoV Immunocomb; Biogal) and three rapid immunochromatographic (RIM) tests against a panel of samples designated by consensus as positive or negative. Specificity was 100% for all but the two IFATs based on transmissible gastroenteritis virus (TGEV), at 83.3% and 97.5%. The IFAT and ELISA tests were best for obtaining an antibody titre and for working in the presence of virus. The RIM tests were the best for obtaining a result quickly (10-15 mins); of these, the Speed F-Corona was the most sensitive, at 92.4%, followed by FASTest feline infectious peritonitis (FIP; 84.6%) and Anigen Rapid FCoV antibody test (64.1%). Sensitivity was 100% for the ELISA, one FCoV IFAT and one TGEV IFAT; and 98.2% for a second TGEV IFA and 96.1% for a second FCoV IFAT. All tests worked with effusions, even when only blood products were stipulated in the instruction manual. The ELISA and Anigen RIM tests were best for small quantities of sample. The most appropriate FCoV antibody test to use depends on the reason for testing: in excluding a diagnosis of FIP, sensitivity, specificity, small sample quantity, rapidity and ability to work in the presence of virus all matter. For FCoV screening, speed and sensitivity are important, and for FCoV elimination antibody titre is essential. © ISFM and AAFP 2014.

  8. Rapid detection of methicillin resistance in coagulase-negative staphylococci by a penicillin-binding protein 2a-specific latex agglutination test.

    PubMed

    Horstkotte, M A; Knobloch, J K; Rohde, H; Mack, D

    2001-10-01

    The detection of PBP 2a by the MRSA-Screen latex agglutination test with 201 clinical coagulase-negative staphylococci had an initial sensitivity of 98% and a high degree of specificity for Staphylococcus epidermidis strains compared to PCR for mecA. Determination of oxacillin MICs evaluated according to the new breakpoint (0.5 microg/ml) of the National Committee for Clinical Laboratory Standards exhibited an extremely low specificity for this population.

  9. Seroprevalence of Toxoplasma gondii antibodies in cats from Durango City, Mexico.

    PubMed

    Alvarado-Esquivel, C; Liesenfeld, O; Herrera-Flores, R G; Ramírez-Sánchez, B E; González-Herrera, A; Martínez-García, S A; Dubey, J P

    2007-10-01

    The prevalence of antibodies to Toxoplasma gondii was determined in sera from 105 domestic cats from Durango City, Mexico. Using a modified agglutination test, antibodies to this parasite were found in 21% of the 105 cats, with titers of 1:25 in 3 cats, 1:50 in 4 cats, 1:200 in 5 cats, 1:400 in 2 cats, 1:800 in 2 cats, 1:1,600 in 4 cats, and 1:3,200 or higher in 2 cats. Cats older than 1 yr had a significantly higher frequency of infection than that found in cats younger than 0.5 yr (41 vs. 13.2%, respectively; odds ratio = 4.55; 95% CI = 1.24-17.18; P = 0.01). Overall, the seroprevalence of T. gondii antibodies in cats in Durango, Mexico, is much lower compared with those reported in other countries.

  10. Mapping the distribution of specific antibody interaction forces on individual red blood cells

    NASA Astrophysics Data System (ADS)

    Yeow, Natasha; Tabor, Rico F.; Garnier, Gil

    2017-02-01

    Current blood typing methods rely on the agglutination of red blood cells (RBCs) to macroscopically indicate a positive result. An indirect agglutination mechanism is required when blood typing with IgG forms of antibodies. To date, the interaction forces between anti-IgG and IgG antibodies have been poorly quantified, and blood group related antigens have never been quantified with the atomic force microscope (AFM). Instead, the total intensity resulting from fluorescent-tagged antibodies adsorbed on RBC has been measured to calculate an average antigen density on a series of RBCs. In this study we mapped specific antibody interaction forces on the RBC surface. AFM cantilever tips functionalized with anti-IgG were used to probe RBCs incubated with specific IgG antibodies. This work provides unique insight into antibody-antigen interactions in their native cell-bound location, and crucially, on a per-cell basis rather than an ensemble average set of properties. Force profiles obtained from the AFM directly provide not only the anti-IgG - IgG antibody interaction force, but also the spatial distribution and density of antigens over a single cell. This new understanding might be translated into the development of very selective and quantitative interactions that underpin the action of drugs in the treatment of frontier illnesses.

  11. Surgical management of vulvovaginal agglutination due to lichen planus.

    PubMed

    Fairchild, Pamela S; Haefner, Hope K

    2016-02-01

    Lichen planus is a rare dermatological disorder that is often associated with painful and disfiguring vulvovaginal effects. At the University of Michigan Center for Vulvar Diseases, we see many women with vulvovaginal lichen planus each year, with marked scarring and vulvovaginal agglutination that precludes vaginal intercourse and causes difficulty with urination. Through our experience, we developed a protocol for the operative management and postoperative care for severe vulvovaginal agglutination. Our objective is to share this protocol with a wider audience so that providers who see patients with these devastating effects of lichen planus can benefit from our experience to better serve this patient population. The figure represents a case of erosive lichen planus with early vaginal agglutination. The video reviews the pathophysiology and presentation of lichen planus. We then present a case of scarring and agglutination in a young woman, including our surgical management and postoperative care recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. A comparison of five serological tests for bovine brucellosis.

    PubMed Central

    Dohoo, I R; Wright, P F; Ruckerbauer, G M; Samagh, B S; Robertson, F J; Forbes, L B

    1986-01-01

    Five serological assays: the buffered plate antigen test, the standard tube agglutination test, the complement fixation test, the hemolysis-in-gel test and the indirect enzyme immunoassay were diagnostically evaluated. Test data consisted of results from 1208 cattle in brucellosis-free herds, 1578 cattle in reactor herds of unknown infection status and 174 cattle from which Brucella abortus had been cultured. The complement fixation test had the highest specificity in both nonvaccinated and vaccinated cattle. The indirect enzyme immunoassay, if interpreted at a high threshold, also exhibited a high specificity in both groups of cattle. The hemolysis-in-gel test had a very high specificity when used in nonvaccinated cattle but quite a low specificity among vaccinates. With the exception of the complement fixation test, all tests had high sensitivities if interpreted at the minimum threshold. However, the sensitivities of the standard tube agglutination test and indirect enzyme immunoassay, when interpreted at high thresholds were comparable to that of the complement fixation test. A kappa statistic was used to measure the agreement between the various tests. In general the kappa statistics were quite low, suggesting that the various tests may detect different antibody isotypes. There was however, good agreement between the buffered plate antigen test and standard tube agglutination test (the two agglutination tests evaluated) and between the complement fixation test and the indirect enzyme immunoassay when interpreted at a high threshold. With the exception of the buffered plate antigen test, all tests were evaluated as confirmatory tests by estimating their specificity and sensitivity on screening-test positive samples.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3539295

  13. Antibodies in sera from camels (Camelus dromedarius) in western and sothren regions of Central Province, Saudi Arabia.

    PubMed

    Al-Anazi, Abdullah D

    2012-12-01

    The study evaluated the seroprevalence of Toxoplasma gondii in domestic camels in Western and Southern regions of Central province of Saudi Arabia. In total, 713 serum samples from clinically healthy camels were analyzed for anti-T. gondii antibodies using the Latex agglutination test (LAT). Antibodies to T. gondii were found in 94 (13.1%) camels. The number of seropositive in Al-Quwayiyah region (16.9%) was considerably higher than in other regions. However, the differences in seroprevalence between the 4 regions were not statistically significant (P >. 0.05). These results indicate that T. gondii antibodies are widespread in the camel populations and suggest that toxoplasmosis is a widely spread zoonotic infection this region.

  14. Interfering lipoproteins in magnetic field-assisted agglutination of superparamagnetic particles immunoassay.

    PubMed

    Cauet, Gilles; Daynès, Aurélien; Temurok, Nevzat

    2016-04-01

    The technology of magnetic field-assisted immuno-agglutination of superparamagnetic particles allows sensitive detection of biomarkers in whole blood. However, we observed non-specific agglutination (NSA), due to interfering plasma proteins, that negatively affects C-reactive protein immunoassay. The objective of the study was to identify the plasma proteins involved and to eliminate these interferences. Plasma was fractionated by size exclusion HPLC and each fraction was tested for non-specific agglutination. In addition, plasma proteins bound to magnetic particles were analyzed by SDS-gel electrophoresis and identified by mass spectrometry. We found that NSA was due to the binding of some lipoproteins to the particles. NSA was observed in the presence of purified LDL and VLDL but not HDL. NSA was mediated by the binding of ApoB100 to magnetic particles through its heparin binding sites. These interferences could be eliminated by addition of heparin or other polyanions like dextran sulfate to the assay buffer. NSA results from the binding of some plasma lipoproteins to magnetic particles. The use of a polyanion to eliminate these interferences allows the formulation of a stable reagent.

  15. False-positive cryptococcal antigen latex agglutination caused by disinfectants and soaps.

    PubMed Central

    Blevins, L B; Fenn, J; Segal, H; Newcomb-Gayman, P; Carroll, K C

    1995-01-01

    Five disinfectants or soaps were tested to determine if any could be responsible for false-positive results obtained with the Latex-Crypto Antigen Detection System kit (Immuno-Mycologics, Inc., Norman, Okla.). Three disinfectants or soaps (Derma soap, 7X, and Bacdown) produced false-positive agglutination after repeated washing of ring slides during testing of a known negative cerebrospinal fluid specimen. PMID:7650214

  16. Systems, devices, and methods for agglutination assays using sedimentation

    DOEpatents

    Schaff, Ulrich Y.; Sommer, Gregory J.; Singh, Anup K.

    2016-01-26

    Embodiments of the present invention include methods for conducting agglutination assays using sedimentation. Aggregates may be exposed to sedimentation forces and travel through a density medium to a detection area. Microfluidic devices, such as microfluidic disks, are described for conducting the agglutination assays, as are systems for conducting the assays.

  17. Antibody to HTLV‐I in Indigenous Inhabitants of the Andes and Amazon Regions in Colombia

    PubMed Central

    Zamora, Tomas; Zaninovic, Vladimir; Kajiwara, Masaharu; Komoda, Haruko; Hayami, Masanori

    1990-01-01

    To explore the HTLV‐I‐carrying groups among the indigenous inhabitants in South America, a sero‐epidemiological study on HTLV‐I focusing on hinterland villages isolated from others in the Andes and Amazon regions was conducted. Five (2.9%) out of 171 subjects showed positive for HTLV‐I antibody in the gelatin particle agglutination (PA) test. Two out of 5 positives with high antibody titer (≫× 1024) in the PA test also showed a positive immunofluorescence (IF) test and anti‐HTLV‐I‐specific protein products, p19, p24, p28, gp46, and p53 in sera by the Western blotting (WB) test. One of three negatives in the IF test showed positive antibodies to p19 and p24 by the WB test. Finally, two were confirmed as HTLV‐I carriers and one was suspected of being a carrier. All three are Paez Indians from the central Andes; 53‐ and 34‐year‐old women and a 35‐year‐old man. The results show that HTLV‐1 carriers exist among isolated indigenous people in South America. PMID:1975804

  18. [The incidence of agglutination and its influence on sperm quality and fertility of boar semen].

    PubMed

    Bollwein, Heinrich; Petschow, Karola; Weber, Frank; Leiding, Claus; Stolla, Rudolf

    2004-01-01

    The aim of this study was to examine the incidence of sperm agglutinations and their relationships with sperm quality and fertility. Semen samples of 40 boars of an AI-station were investigated. Nineteen of the 40 investigated boars showed a constantly low (< 10% agglutinated sperm), 3 an intermediate (10-20%) and 6 boars a high level (> 20%) of agglutination in raw semen. The degree of agglutination in sperm samples of 12 boars varied distinctly during the investigation period. During summer more (P < 0.05) agglutinated sperm were observed (11.0 +/- 11.6%) than during winter (6.2 +/- 7.3%). There was no association between bacterial contamination and incidence of agglutinations (P > 0.05). After dilution in extender the percentage of agglutinated sperm decreased from 6.2 +/- 7.3% to 1.1 +/- 1.4% (P < 0.0001). Twenty-four hours after dilution the percentage of progressively motile sperm was 7.4% lower (P < 0.05) in ejaculates with an initially high degree of agglutination (> 20% agglutinated sperm) compared to samples with an initially low degree of agglutinated sperm (< 10%). Plasma membrane integrity, mitochondrial membrane potential, acrosome reaction and chromatin structure were independent (P > 0.05) from the level of agglutination. Fertility data did not differ (P > 0.05) between boars with low and high numbers of agglutinated sperm in raw semen. The results show that there are individual, ejaculatory and seasonal variations in the incidence and degree of agglutination. Agglutinations have a negative effect on motility of sperm and disappear to a large extent after dilution in sperm extender. They have no negative consequences on fertility.

  19. Evaluation of the co-agglutination test in diagnosis of experimental microsporidiosis.

    PubMed

    Gaafar, Maha R

    2011-05-01

    Microsporidiosis is an emerging and opportunistic infection associated with wide range of clinical syndromes in humans. Confirmation of the presence of microsporidia in different samples is laborious, costly and often difficult. The present study was designed to evaluate the utility of the Co-agglutination test (Co-A test) for detection of urinary, fecal and circulating microsporidial antigens in experimentally infected mice. One hundred and twenty male Swiss albino mice were divided into non infected control and infected experimental groups which were further subdivided into two equal subgroups; immunosuppressed and immunocompetent. Microsporidial spores were isolated from human stools and identified to be Encephalitozoon intestinalis by the molecular methods. They were used to infect each subgroup of mice, then their urine, stools and sera were collected at the 1st, 3rd, 5th, 7th and 9th days post-infection (PI). Co-A test, using prepared hyperimmune serum, was used to detect antigens in all samples collected. The cross reactivity of microsporidial hyperimmune sera with antigens of Cyclospora cyatenensis and Cryptosporidium parvum was investigated by Co-A test. The results showed that Co-A test was effective in detecting microsporidial antigen in stool of immunosuppressed infected mice from the 1st day PI, and in urine and serum from the 3rd day PI till the end of the study. In the immunocompetent subgroup, Co-A test detected microsporidial antigens in stool, serum and urine of mice from the 1st day, 3rd day and the 5th day PI, respectively till the end of the study, without cross reactivity with C. cyatenensis or C. parvum in both subgroups. Co-A test proved to be simple and suitable tool for detecting microsporidial antigen in different specimens and did not need sophisticated equipment. It is very practical under field or rural conditions and in poorly equipped clinical laboratories. Copyright © 2011 Elsevier Inc. All rights reserved.

  20. Case report: false negative serum cryptococcal latex agglutination test in a patient with disseminated cryptococcal disease.

    PubMed

    Navabi, Nazlee; Montebatsi, Milton; Scott, Michelle; Gluckman, Stephen J; Reid, Michael J A

    2015-01-01

    A case of false-negative serum latex agglutination cryptococcal antigen (CRAG) test in a 45-year-old HIV-positive male with Cryptococcus-positive culture is described. The patient was presented to a hospital in Botswana, with breathlessness and a diffuse papular rash. His CD4 count was 25 cells/μL. Despite the suspicion for disseminated cryptococcal disease, an initial serum CRAG latex test was negative. Results of subsequent Indian ink staining, culture of cerebrospinal fluid and skin scrapings, and serum lateral flow immunoassay (LFA) were all positive for Cryptococcus neoformans. There are several possible explanations for the false-negative CRAG latex test. Given the positive LFA result, we speculate that disease may have been caused by Cryptococcus gattii, which is estimated to be responsible for between 15% and 30% of all cryptococcal diseases in Botswana. Reduced sensitivity of CRAG latex assays for detecting C gattii may lead to underdiagnosis of cryptococcal infection. © The Author(s) 2014.

  1. Impacts of papain and neuraminidase enzyme treatment on electrohydrodynamics and IgG-mediated agglutination of type A red blood cells.

    PubMed

    Hyono, Atsushi; Gaboriaud, Fabien; Mazda, Toshio; Takata, Youichi; Ohshima, Hiroyuki; Duval, Jérôme F L

    2009-09-15

    The stability of native and enzyme-treated human red blood cells of type A (Rh D positive) against agglutination is investigated under conditions where it is mediated by immunoglobuline G (IgG) anti-D antibody binding. The propensity of cells to agglutinate is related to their interphasic (electrokinetic) properties. These properties significantly depend on the concentration of proteolytic papain enzyme and protease-free neuraminidase enzyme that the cells are exposed to. The analysis is based on the interpretation of electrophoretic data of cells by means of the numerical theory for the electrokinetics of soft (bio)particles. A significant reduction of the hydrodynamic permeability of the external soft glycoprotein layer of the cells is reported under the action of papain. This reflects a significant decrease in soft surface layer thickness and a loss in cell surface integrity/rigidity, as confirmed by nanomechanical AFM analysis. Neuraminidase action leads to an important decrease in the interphase charge density by removing sialic acids from the cell soft surface layer. This is accompanied by hydrodynamic softness modulations less significant than those observed for papain-treated cells. On the basis of these electrohydrodynamic characteristics, the overall interaction potential profiles between two native cells and two enzyme-treated cells are derived as a function of the soft surface layer thickness in the Debye-Hückel limit that is valid for cell suspensions under physiological conditions (approximately 0.16 M). The thermodynamic computation of cell suspension stability against IgG-mediated agglutination then reveals that a decrease in the cell surface layer thickness is more favorable than a decrease in interphase charge density for inducing agglutination. This is experimentally confirmed by agglutination data collected for papain- and neuraminidase-treated cells.

  2. The Classroom-Friendly ABO Blood Types Kit: Blood Agglutination Simulation

    ERIC Educational Resources Information Center

    Arnold, Savittree Rochanasmita; Kruatong, Tussatrin; Dahsah, Chanyah; Suwanjinda, Duongdearn

    2012-01-01

    The classroom-friendly ABO blood type kit was developed by combining advantages of modelling and a simulation laboratory to teach the topics of ABO blood types and blood transfusion. Teachers can easily simulate the agglutination reaction on a blood type testing plate in the classroom, and show the students how this reaction occurs by using the…

  3. Differential Lectin Agglutination of Fetal, Dividing-Postnatal, and Malignant Hepatocytes

    PubMed Central

    Becker, F. F.

    1974-01-01

    Numerous studies have reported the capacity of the lectin, concanavalin A, to agglutinate selected cell-types. The finding that cells transformed in culture, embryonic cells, and malignant cells are all agglutinated by this substance, may contribute to our understanding of the oncogenic process. The present study compared the response to concanavalin A of rat hepatocytes derived from livers of differing developmental and mitotic-status as well as those derived from malignant liver tumors (hepatomas). Fetal hepatocytes and hepatoma cells were highly susceptible to agglutination while hepatocytes from post-natal livers, whether dividing or quiescent, were not. Treatment with protease(s) did not make the interphase hepatocyte agglutinable. These data emphasize the importance of examining a wide variety of cells in attempting to understand the interaction of lectins on cell surfaces, and further, demonstrate the value of obtaining cells directly from tissue(s) during differing physiologic and pathologic states. Images PMID:4373708

  4. Polyclonal and monoclonal antibodies in clinic.

    PubMed

    Wootla, Bharath; Denic, Aleksandar; Rodriguez, Moses

    2014-01-01

    Immunoglobulins (Ig) or antibodies are heavy plasma proteins, with sugar chains added to amino-acid residues by N-linked glycosylation and occasionally by O-linked glycosylation. The versatility of antibodies is demonstrated by the various functions that they mediate such as neutralization, agglutination, fixation with activation of complement and activation of effector cells. Naturally occurring antibodies protect the organism against harmful pathogens, viruses and infections. In addition, almost any organic chemical induces antibody production of antibodies that would bind specifically to the chemical. These antibodies are often produced from multiple B cell clones and referred to as polyclonal antibodies. In recent years, scientists have exploited the highly evolved machinery of the immune system to produce structurally and functionally complex molecules such as antibodies from a single B clone, heralding the era of monoclonal antibodies. Most of the antibodies currently in the clinic, target components of the immune system, are not curative and seek to alleviate symptoms rather than cure disease. Our group used a novel strategy to identify reparative human monoclonal antibodies distinct from conventional antibodies. In this chapter, we discuss the therapeutic relevance of both polyclonal and monoclonal antibodies in clinic.

  5. Antibody Blood Tests

    MedlinePlus

    ... out for sure? If antibody tests and/or symptoms suggest celiac disease, the physician needs to establish the diagnosis by ... who is still experiencing symptoms, to establish the diagnosis or to rule out celiac disease as a part of establishing another diagnosis. Find ...

  6. Agglutination of intravenously administered phosphatidylcholine-containing lipid emulsions with serum C-reactive protein.

    PubMed

    Tugirimana, Pierrot; Speeckaert, Marijn M; Fiers, Tom; De Buyzere, Marc L; Kint, Jos; Benoit, Dominique; Delanghe, Joris R

    2013-04-01

    C-reactive protein (CRP) is able to bind phospholipids in the presence of calcium. We wanted to investigate the reaction of CRP with various commercial fat emulsions and to explore the impact of CRP agglutination on serum CRP levels. Serum specimens were mixed with Intralipid 20% (soybean oil-based fat emulsion), Structolipid (structured oil-based fat emulsion), Omegaven (fish oil-based fat emulsion), or SMOFlipid (mixed soybean oil-, olive oil-, and fish oil-based emulsion) in Tris-calcium buffer (pH 7.5). After 30 minutes of incubation at 37°C, CRP-phospholipid complexes were turbidimetrically quantified and flow cytometric analysis was performed. Similarly, CRP complexes were monitored in vivo, following administration of fat emulsion. CRP was able to agglutinate phospholipid-containing lipid droplets present in the soybean oil-based fat emulsion and the structured oil-based fat emulsion. To a lesser extent, agglutination was observed for fish oil-containing fat emulsions, whereas no agglutination was noticed for the mixed soybean oil-, olive oil-, and fish oil-based emulsion. Results for propofol-containing emulsions were comparable. Agglutination correlated with phospholipid content of the emulsions. When in vivo agglutination occurred, plasma CRP values dropped due to consumption of CRP by phospholipid-induced agglutination. In this in vitro experiment, we demonstrated agglutination of CRP with phospholipids in various fat emulsions. Research studies are required in patients to determine which effects occur with various intravenous fat emulsions.

  7. Generation and selection of anti-flagellin monoclonal antibodies useful for serotyping Salmonella enterica.

    PubMed

    Hiriart, Yanina; Serradell, Maria; Martínez, Araci; Sampaolesi, Sofia; Maciel, Dolores Gonzalez; Chabalgoity, Jose Alejandro; Yim, Lucía; Algorta, Gabriela; Rumbo, Martin

    2013-01-01

    In developing countries, bacterial acute gastroenteritis continues to be an important cause of morbidity and mortality among young children. Salmonellosis constitutes a major cause of infectious enteritis worldwide, most of them associated to the consumption of contaminated food products. Traditionally, Salmonella has been classified in serovars based on varieties of O and H surface antigens. In the present work we generated and characterized a panel of anti-flagellin monoclonal antibodies (MAbs) in order to select antibodies useful for detecting the H surface antigen. Four different MAbs were obtained by somatic hybridization of splenocytes. We found two MAbs that recognised regions of flagellin conserved among different Salmonella serovars. Other two MAbs recognised structures restricted to Salmonella enterica sv. Typhimurium, being one of them suitable for agglutination tests. Using a diverse panel of S. enterica serovars with different H antigen varieties we confirmed that this MAb agglutinates specifically S. Typhimurium (antigenic formula: 4,12:i:1,2) or other serovars expressing flagellar factor i. In conclusion, we generated a valuable immunochemical tool to be used in simple assays for serotyping of epidemiologically relevant strains. The capacity to characterize specific strains and determine the primary sources of Salmonella contamination generate valuable information of the epidemiology of this microorganism, contributing to the improvement of public health.

  8. Tumour growth, phagocytic activity and antibody response in corynebacterium parvum-treated mice

    PubMed Central

    Woodruff, M. F. A.; McBride, W. H.; Dunbar, Noreen

    1974-01-01

    Serum from both normal and T cell-deprived female adult CBA mice shows a background titre of antibody to Corynebacterium parvum of about 2–4 log2 units by a latex agglutination test. Intraperitoneal injection of C. parvum causes a marked rise in titre which reaches its peak after about a month, and a second injection at that time evokes a further response. Treatment with mercaptoethanol reduces the background titre, and also the titre 1–3 weeks after immunization by 1–2 log units. Subcutaneous injection of C. parvum on the other hand evokes little or no antibody response. Both the antitumour effect of C. parvum, and its effect on clearance of colloidal carbon from the blood stream, can occur in the presence of high levels of antibody directed against the organism. Theoretical and possible therapeutic implications of these findings are discussed. PMID:4549691

  9. Culturing and extraction of Coprococcus comes, absorption of serumagglutinins by soluble fractions and relation between agglutinins and antibodies in sera of patients with Crohn's disease.

    PubMed

    Hazenberg, M P; Pennock-Schröder, A M; van de Merwe, J P

    1986-01-01

    Agglutinating antibodies to Coprococcus comes and three other obligately anaerobic coccoid rods from the intestinal flora are used in the diagnosis of Crohn's disease. Further studies on the pathogenetic role as well as the development of more sensitive and specific methods for detecting antibodies require extraction of the antigen fractions. Culturing methods to obtain C. comes with optimal antigen presentation and isolation of soluble antigen fractions were therefore developed. Hot water extraction of whole cells and subsequent removal of proteins with trichloroacetic acid provided a fraction that absorbed serum agglutinins, was useful for an enzyme-linked immunosorbent assay and induced agglutinating antibodies in rats.

  10. Behavioral and Psychological Responses to HIV Antibody Testing.

    ERIC Educational Resources Information Center

    Jacobsen, Paul B.; And Others

    1990-01-01

    Considers effects of informing individuals of their antibody status as determined by human immunodeficiency virus (HIV) antibody testing. Reviews research examining changes in psychological distress and in behaviors associated with HIV infections among individuals who have undergone antibody testing. Identifies methodological issues in studying…

  11. Lack of Sarcocystis neurona antibody response in Virginia opossums (Didelphis virginiana) fed Sarcocystis neurona-infected muscle tissue.

    PubMed

    Cheadle, M A; Lindsay, D S; Greiner, E C

    2006-06-01

    Serum was collected from laboratory-reared Virginia opossums (Didelphis virginiana) to determine whether experimentally infected opossums shedding Sarcocystis neurona sporocysts develop serum antibodies to S. neurona merozoite antigens. Three opossums were fed muscles from nine-banded armadillos (Dasypus novemcinctus), and 5 were fed muscles from striped skunks (Mephitis mephitis). Serum was also collected from 26 automobile-killed opossums to determine whether antibodies to S. neurona were present in these opossums. Serum was analyzed using the S. neurona direct agglutination test (SAT). The SAT was modified for use with a filter paper collection system. Antibodies to S. neurona were not detected in any of the serum samples from opossums, indicating that infection in the opossum is localized in the small intestine. Antibodies to S. neurona were detected in filter-paper-processed serum samples from 2 armadillos naturally infected with S. neurona.

  12. Heparin-Induced Thrombocytopenia Antibody Test

    MedlinePlus

    ... HIT II is clinically suspected. There is a pre-test scoring system that is typically used to determine ... The HIT antibody test is performed when this pre-scoring test shows that a person has a moderate to ...

  13. Latex agglutination test

    MedlinePlus

    ... Some labs use different measurements or test different samples. Talk to your provider about the meaning of your ... saliva test. BLOOD TEST Veins and arteries vary in size from one person to another and from one side of ...

  14. The latex agglutination test versus counterimmunoelectrophoresis for rapid diagnosis of bacterial meningitis

    PubMed Central

    Bortolussi, Robert; Wort, Arthur J.; Casey, Stephanie

    1982-01-01

    A modified latex agglutination (LA) test was compared with Gram-staining and counterimmunoelectrophoresis (CIE) for the rapid detection in the cerebrospinal fluid (CSF) of antigen to Haemophilus influenzae type b, Neisseria meningitidis groups A, B and C, Escherichia coli K1, Streptococcus pneumoniae and group B streptococci, seven frequent causes of bacterial meningitis in children. Of 50 CSF samples from patients with culture-proven bacterial meningitis 90% were correctly shown by the LA test to contain antigen of the responsible organism. Gram-staining revealed organisms in 80% of 45 of these samples. In 75% of the 40 samples that were of sufficient volume for CIE, positive results for the appropriate antigen were obtained. The concentration of antigen detected in the CSF by the LA test varied from undetectable to 800 000 ng/ml. Patients with a high concentration (more than 2000 ng/ml or a positive result at dilutions of CSF over 1/8) were significantly more likely to have a poor response to therapy (two died and two had persistent pleocytosis or bacteria in the CSF) than patients with a lower concentration (4/16 v. 0/18, P < 0.05). After appropriate therapy was begun the concentration of antigen fell dramatically, but measurable amounts of antigen persisted in the CSF for up to 6 days. The LA test detected bacterial antigen at concentrations 2 to 70 times below the lower limit detected by CIE. In seven additional patients who had received antibiotics before lumbar puncture was performed the LA test detected antigen from meningitis-causing bacteria even though cultures of the CSF were sterile. In another 145 patients who did not have meningitis the results of the LA test were negative. The LA test, done as described in this article, is easier to perform than CIE and should be a useful addition to the diagnostic tests carried out on the CSF of any patient suspected of having meningitis. PMID:6749272

  15. 21 CFR 866.5110 - Antiparietal antibody immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5110 Antiparietal antibody immunological test system. (a) Identification. An antiparietal antibody... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antiparietal antibody immunological test system...

  16. 21 CFR 866.5100 - Antinuclear antibody immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5100 Antinuclear antibody immunological test system. (a) Identification. An antinuclear antibody... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antinuclear antibody immunological test system...

  17. Laboratory Evaluation of a Smartphone-Based Electronic Reader of Rapid Dual Point-of-Care Tests for Antibodies to Human Immunodeficiency Virus and Treponema pallidum Infections.

    PubMed

    Herbst de Cortina, Sasha; Bristow, Claire C; Humphries, Romney; Vargas, Silver Keith; Konda, Kelika A; Caceres, Carlos F; Klausner, Jeffrey D

    2017-07-01

    Dual point-of-care tests for antibodies to human immunodeficiency virus (HIV) and Treponema pallidum allow for same-day testing and treatment and have been demonstrated to be cost-effective in preventing the adverse outcomes of HIV infection and syphilis. By recording and transmitting data as they are collected, electronic readers address challenges related to the decentralization of point-of-care testing. We evaluated a smartphone-based electronic reader using 201 sera tested with 2 dual rapid tests for detection of antibodies to HIV and T. pallidum in Los Angeles, USA, and Lima, Peru. Tests were read both visually and with the electronic reader. Enzyme immunoassay followed by Western blot and T. pallidum particle agglutination were the reference tests for HIV and T. pallidum, respectively. The sensitivities of the 2 rapid tests for detection of HIV were 94.1% and 97.0% for electronic readings. Both tests had a specificity of 100% for detection of HIV by electronic reading. The sensitivities of the 2 rapid tests for detection of T. pallidum were 86.5% and 92.4% for electronic readings. The specificities for detection of T. pallidum were 99.1% and 99.0% by electronic reading. There were no significant differences between the accuracies of visual and electronic readings, and the performance did not differ between the 2 study sites. Our results show the electronic reader to be a promising option for increasing the use of point-of-care testing programs.

  18. Evolution of Shock Melt Compositions in Lunar Agglutinates

    NASA Technical Reports Server (NTRS)

    Vance, A. M.; Christoffersen, R.; Keller, L. P.

    2015-01-01

    Lunar agglutinates are aggregates of regolith grains fused together in a glassy matrix of shock melt produced during smaller-scale (mostly micrometeorite) impacts. Agglutinate formation is a key space weathering process under which the optically-active component of nanophase metallic Fe (npFe(sup 0)) is added to the lunar regolith. Here we have used energy-dispersive X-ray (EDX) compositional spectrum imaging in the SEM to quantify the chemical homogeneity of agglutinitic glass, correlate its homogeneity to its parent soil maturity, and identify the principle chemical components contributing to the shock melt compositional variations.

  19. Determination of degree of RBC agglutination for blood typing using a small quantity of blood sample in a microfluidic system.

    PubMed

    Chang, Yaw-Jen; Ho, Ching-Yuan; Zhou, Xin-Miao; Yen, Hsiu-Rong

    2018-04-15

    Blood typing assay is a critical test to ensure the serological compatibility of a donor and an intended recipient prior to a blood transfusion. This paper presents a microfluidic blood typing system using a small quantity of blood sample to determine the degree of agglutination of red blood cell (RBC). Two measuring methods were proposed: impedimetric measurement and electroanalytical measurement. The charge transfer resistance in the impedimetric measurement and the power parameter in the electroanalytical measurement were used for the analysis of agglutination level. From the experimental results, both measuring methods provide quantitative results, and the parameters are linearly and monotonically related to the degree of RBC agglutination. However, the electroanalytical measurement is more reliable than the impedimetric technique because the impedimetric measurement may suffer from many influencing factors, such as chip conditions. Five levels from non-agglutination (level 0) to strong agglutination (level 4+) can be discriminated in this study, conforming to the clinical requirement to prevent any risks in transfusion. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

    NASA Technical Reports Server (NTRS)

    Laul, J. C.; Smith, M. R.; Papike, J. J.; Simon, S. B.

    1984-01-01

    Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

  1. Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

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

    Laul, J.C.; Smith, M.R.

    1984-11-15

    Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

  2. Lack of chemical fractionation in major and minor elements during agglutinate formation. [in lunar soil

    NASA Technical Reports Server (NTRS)

    Hu, H.-N.; Taylor, L. A.

    1977-01-01

    Rhodes et al. (1975, 1976) and Adams et al. (1975) have reported that the agglutinate fraction of the soils on the lunar surface displays a marked enrichment in Fe, Mg, Ti, K, and La, and a depletion in Ca, Na, Al, and Eu, relative to the bulk soils. The reported investigation is concerned with a testing of the theory of chemical fractionation involving magnetic separation which was developed in connection with these findings. Soils 64421 and 71501 were sieved and the magnetic fractions separated according to the method developed by Adams and McCord (1973). Analyses of agglutinitic glass did not indicate any appreciable chemical fractionation for the major and minor elements accompanying the agglutination process. It was found that most, if not all fractionations reported can be accounted for completely by the magnetic nonagglutinate impurities in the agglutinate fraction. It is, therefore, concluded that there appears to be no reason to make use of any chemical fractionation theory, whose validity remains to be demonstrated.

  3. Prevalence of naturally occurring antibodies against dog erythrocyte antigen 7 in a population of dog erythrocyte antigen 7-negative dogs from Spain and Italy.

    PubMed

    Spada, Eva; Proverbio, Daniela; Viñals Flórez, Luis Miguel; Del Rosario Perlado Chamizo, Maria; Serra Y Gómez de la Serna, Blanca; Perego, Roberta; Baggiani, Luciana

    2016-08-01

    OBJECTIVE To determine the prevalence of naturally occurring anti-dog erythrocyte antigen (DEA) 7 antibodies in DEA 7-negative dogs from Spain and Italy. ANIMALS 252 DEA 7-negative dogs from a population of 312 dogs that were previously tested for DEA 1, DEA 4, and DEA 7. PROCEDURES A plasma sample was obtained from each dog and evaluated for anti-DEA 7 antibodies by the use of gel column agglutination. Each plasma sample underwent major crossmatching with RBCs from DEA 7-positive dogs. Samples that resulted in agglutination were then crossmatched with RBCs from DEA 1-negative, DEA 4-positive, and DEA 7-negative dogs to confirm the presence of anti-DEA 7 antibodies. Results were then used to calculate the risk for a delayed transfusion reaction in a DEA 7-negative dog with anti-DEA 7 antibodies after a transfusion with blood that was not crossmatched or typed for DEA 7. RESULTS 96 of 252 (38.1%) plasma samples contained anti-DEA 7 antibodies. A DEA 7-negative dog with anti-DEA 7 antibodies had a 5.9% chance of developing a delayed hemolytic reaction after transfusion with blood not crossmatched or typed for DEA 7. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that canine blood used for transfusion should be crossmatched with the blood or plasma of the intended recipient prior to transfusion to minimize the likelihood that the recipient will develop a hemolytic reaction associated with anti-DEA 7 antibodies. Ideal canine blood donors should be negative for both DEA 1 and DEA 7.

  4. Lipopolysaccharide-Specific but Not Anti-Flagellar Immunoglobulin A Monoclonal Antibodies Prevent Salmonella enterica Serotype Enteritidis Invasion and Replication within HEp-2 Cell Monolayers

    PubMed Central

    Iankov, Ianko D.; Petrov, Dragomir P.; Mladenov, Ivan V.; Haralambieva, Iana H.; Mitov, Ivan G.

    2002-01-01

    The protective potential of immunoglobulin A (IgA) monoclonal antibodies (MAbs) directed against O and H antigens of Salmonella enterica serotype Enteritidis to prevent bacterial adhesion to and invasion of HEp-2 cells was evaluated. Although anti-flagellar IgA MAbs showed strong agglutinating capacities, they did not protect cell monolayers. In contrast, IgA MAbs specific for the O:9 epitope of Salmonella lipopolysaccharide antigen alone prevented S. enterica serotype Enteritidis entry and replication within HEp-2 cells, and the protection was not mediated by direct binding of antibodies to bacterial adhesins or by agglutination of microorganisms. PMID:11854252

  5. Typing of Haemophilus influenzae by Coagglutination and Conventional Slide Agglutination

    PubMed Central

    Shively, Roxanne G.; Shigel, Janet T.; Peterson, Ellena M.; De La Maza, Luis M.

    1981-01-01

    Coagglutination was compared with conventional slide agglutination for the typing of 297 clinical isolates of Haemophilus sp. A 100% correlation was found with the H. influenzae type b isolates. Coagglutination showed no false-positive reactions with the nontypable strains of H. influenzae and H. parainfluenzae isolates; however, conventional slide agglutination exhibited many false-positive and non-interpretable reactions. PMID:6977555

  6. [Antibacterial antibodies in human immunoglobulins and sera: past and present].

    PubMed

    Romanov, V A; Kulibin, A Iu; Zaĭtseva, I P

    2010-01-01

    To measure levels of several types of antibacterial antibodies in preparations of normal human immunoglobulin as well as in samples of donor sera obtained in 1965 and 2009. Five batches of human normal immunoglobulin manufactured in 1965 and five batches manufactured in 2009 as well as 77 and 28 blood serum samples respectively were tested by agglutination assay for the presence of antibodies to enterobacteria, Brucella species, tularemia agent, Rickettsia burnetii, Rickettsia prowazekii, and several species of opportunistic bacteria. Higher antibody titers to Salmonella typhi, Salmonella paratyphi A and B, Salmonella enteritidis, Salmonella typhimurium, Shigella flexneri and Shigella sonnei were revealed in immunoglobulin preparations and donor sera obtained in 1965 compared to that obtained in 2009. There was no difference in antibody titers to Shigella boydii, Salmonella choleraesuis, Escherichia coli O-55, Pseudomonas aeruginosa, Proteus vulgaris, Serratia marcescens and E. coli. Antibodies to Brucella species, tularemia agent, R. burnetii, R. prowazekii were not detected in normal human immunoglobulin. Decrease of antibody levels to several pathogenic enterobacteria in human immunoglobulin preparations as well as in sera of donors for 40 years could be linked with decrease of number of immunized persons, changes in circulation of pathogenic bacteria, decrease of rate of asymptomatic infections. Stability of antibody titers to opportunistic bacteria is a rationale to use them for assessment of humoral immunity function.

  7. A solid-phase assay for the detection of anti-sperm antibodies.

    PubMed

    Okada, H; Kamidono, S; Owens, G R; Nagamatsu, G R; Addonizio, J C

    1993-05-01

    ELISA is an ideal assay method for a large-scale screening of anti-sperm antibodies among a large number of infertile males. However, conventional ELISA with whole spermatozoa needs time-consuming steps of centrifugation. A solid-phase assay used for detecting anti-sperm antibodies was established. This assay is suitable not only for detecting circulating anti-sperm antibodies of IgG, IgM, and IgA subclass simultaneously but also for screening hybridomas secreting anti-sperm monoclonal antibodies (mAbs). The microtiter plates, on which solubilized sperm antigens are fixed, can be stored at -80 degrees C for up to six months without losing reactivity with anti-sperm antibodies. Using this assay, 53 sera (13 were proven positive and 40 were proven negative for sperm agglutination antibody) were tested. Although the false-negative rate was 0%, the false-positive rate was 32%. One thousand one hundred sixty-five supernatants from hybridomas constructed with splenocytes of mice who were hyperimmunized with human sperm and nonsecreting myeloma cells were tested by this solid-phase assay and two anti-sperm mAb secreting clones were selected and established. It is recommended that for research work this assay could be used for the first screening of the hybridoma secreting anti-sperm mAb, and for clinical use this assay might be suitable for the first screening of sera of infertile patients. However, conventional bioassays should follow to confirm the biological meaning of the positivity.

  8. Limited value of testing for intrinsic factor antibodies with negative gastric parietal cell antibodies in pernicious anaemia.

    PubMed

    Khan, S; Del-Duca, C; Fenton, E; Holding, S; Hirst, J; Doré, P C; Sewell, W A C

    2009-05-01

    The appropriate testing strategy for diagnosing pernicious anaemia using gastric parietal cell (GPC) and/or intrinsic factor antibodies (IFA) is controversial. Intrinsic factor antibodies are found in only about 70% of cases. Indirect immunofluorescence screening for gastric parietal cell antibodies is more sensitive, labour intensive, and less specific. The frequency of antibody positivity (IFA and/or GPC) was retrospectively examined in patients tested for both autoantibodies over a three-year period. It was investigated whether B12 levels were related to antibody status. These findings were validated in a prospective study of IFA in 91 GPC negative patients with low B12 levels. Of 847 samples identified in the retrospective study, 4 (0.47%) were positive for only intrinsic factor antibodies, 731 (86.3%) positive for GPC alone, and 112 (13.2%) for both. Student t test on log-transformed data showed B12 levels had no bearing on autoantibody status. 91 consecutive patients with low B12 levels were tested for both autoantibodies; all were negative for gastric parietal cell antibodies. Only one sample was positive for intrinsic factor antibody using the porcine intrinsic factor assay, but was negative by a human recombinant intrinsic factor-based ELISA. This study provides evidence that testing for gastric parietal cell antibodies is an appropriate screening test for pernicious anaemia, with intrinsic factor antibodies reserved for confirmatory testing or in patients with other autoantibodies that mask the GPC pattern; B12 levels are not related to autoantibody status.

  9. Development of a vaccine to mitigate greenhouse gas emissions in agriculture: vaccination of sheep with methanogen fractions induces antibodies that block methane production in vitro.

    PubMed

    Wedlock, D N; Pedersen, G; Denis, M; Dey, D; Janssen, P H; Buddle, B M

    2010-02-01

    To develop an understanding of the immune responses of ruminants to methanogens, and to provide proof of a concept that harnessing the immune system of ruminants is a potentially viable approach to mitigate greenhouse gas emissions from agriculture. Four subcellular fractions, namely cytoplasmic, two cell-wall preparations, and cell wall-derived proteins were prepared from Methanobrevibacter ruminantium M1. Twenty sheep (10 months of age) were vaccinated with these fractions or with whole cells (n=4 per group). Sheep were re-vaccinated once after 3 weeks, and antibody responses to M. ruminantium M1 antigens in sera and saliva measured using ELISA at 2 weeks after the second vaccination. Antigens recognised by the antisera were visualised using Western blotting. The antisera were tested in vitro for their impact on M. ruminantium M1, measuring the effect on cell growth, methane production, and ability to induce agglutination. Basal levels (pre-vaccination) of antibodies against M. ruminantium M1 antigens were low. Vaccination with the antigenic fractions induced strong antibody responses in serum. Both IgG and IgA responses to methanogen antigens were detected in saliva following vaccination. Western blot analysis of the antisera indicated reactivity of antibodies, and a wide range of proteins was present in the different methanogen fractions. Antisera against the various fractions agglutinated methanogens in an in-vitro assay. In addition, these antisera decreased the growth of a pure culture of a methanogen and production of methane in vitro. Antigens from methanogens are immunogenic in ruminants, and antisera from sheep vaccinated with fractions of methanogens have a significant impact on these organisms, inducing cell agglutination, and decreasing growth of methanogens and production of methane. Only antisera to selected methanogen fractions were able to achieve these effects. The results demonstrate the feasibility of a vaccination strategy to mitigate emission

  10. 21 CFR 866.5090 - Antimitochondrial antibody immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Systems § 866.5090 Antimitochondrial antibody immunological test system. (a) Identification. An antimitochondrial antibody immunological test system is a device that consists of the reagents used to measure by... of diseases that produce a spectrum of autoantibodies (antibodies produced against the body's own...

  11. Comparison of optomagnetic and AC susceptibility readouts in a magnetic nanoparticle agglutination assay for detection of C-reactive protein.

    PubMed

    Fock, Jeppe; Parmvi, Mattias; Strömberg, Mattias; Svedlindh, Peter; Donolato, Marco; Hansen, Mikkel Fougt

    2017-02-15

    There is an increasing need to develop biosensor methods that are highly sensitive and that can be combined with low-cost consumables. The use of magnetic nanoparticles (MNPs) is attractive because their detection is compatible with low-cost disposables and because application of a magnetic field can be used to accelerate assay kinetics. We present the first study and comparison of the performance of magnetic susceptibility measurements and a newly proposed optomagnetic method. For the comparison we use the C-reactive protein (CRP) induced agglutination of identical samples of 100nm MNPs conjugated with CRP antibodies. Both methods detect agglutination as a shift to lower frequencies in measurements of the dynamics in response to an applied oscillating magnetic field. The magnetic susceptibility method probes the magnetic response whereas the optomagnetic technique probes the modulation of laser light transmitted through the sample. The two techniques provided highly correlated results upon agglutination when they measure the decrease of the signal from the individual MNPs (turn-off detection strategy), whereas the techniques provided different results, strongly depending on the read-out frequency, when detecting the signal due to MNP agglomerates (turn-on detection strategy). These observations are considered to be caused by differences in the volume-dependence of the magnetic and optical signals from agglomerates. The highest signal from agglomerates was found in the optomagnetic signal at low frequencies. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Agglutination of human erythrocytes by the interaction of Zn(2+)ion with histidine-651 on the extracellular domain of band 3.

    PubMed

    Kiyotake, Kento; Ochiai, Hideharu; Yamaguchi, Takeo

    2016-05-01

    Clustering of band 3, chloride/bicarbonate exchanger, has been reported in Zn(2+)-treated human erythrocytes. However, the agglutination of human erythrocytes is also induced by the interaction of Zn(2+)ion with histidine on band 3. Identification of histidine that interacts with Zn(2+)ion remains to be determined. The Zn(2+)-induced agglutination of human erythrocytes was unaffected by chymotrypsin cleavage of the small loop region containing His-547 in the extracellular domain of band 3. On the other hand, papain digestion of the large loop region containing His-651 in band 3 inhibited such Zn(2+)-induced agglutination. Moreover, Zn(2+)-induced erythrocyte agglutination was inhibited by the peptide (ARGWVIHPLG) containing His-651, but not by the peptide such as ARGWVIRPLG, which His-651 was substituted by arginine. Among 10 kinds of animal erythrocytes tested, interestingly, no agglutination by Zn(2+)ions was observed in cow cells only that the forth amino acid in the upstream from His-669 on the large loop of cow band 3 is aspartate (Asp-665) instead of glycine. As expected, the agglutination of human erythrocytes by Zn(2+) ions was inhibited in the presence of aspartate. These data indicate that the interaction of Zn(2+) ion with His-651 residue of band 3 plays an important role in the Zn(2+)-induced agglutination of human erythrocytes. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Evaluation of Gamma Interferon and Antibody Tuberculosis Tests in Alpacas

    PubMed Central

    Holder, Tom; Clifford, Derek; Dexter, Ian; Brewer, Jacky; Smith, Noel; Waring, Laura; Crawshaw, Tim; Gillgan, Steve; Lyashchenko, Konstantin; Lawrence, John; Clarke, John; de la Rua-Domenech, Ricardo; Vordermeier, Martin

    2012-01-01

    We describe the performance of cell-based and antibody blood tests for the antemortem diagnosis of tuberculosis (TB) in South American camelids (SAC). The sensitivity and specificity of the gamma interferon (IFN-γ) release assay, two lateral flow rapid antibody tests (Stat-Pak and Dual Path Platform [DPP]), and two enzyme-linked immunosorbent assay (ELISA)-based antibody tests (Idexx and Enferplex) were determined using diseased alpacas from Mycobacterium bovis culture-confirmed breakdown herds and TB-free alpacas from geographical areas with no history of bovine TB, respectively. Our results show that while the sensitivities of the IFN-γ and antibody tests were similar (range of 57.7% to 66.7%), the specificity of the IFN-γ test (89.1%) was lower than those of any of the antibody tests (range of 96.4% to 97.4%). This lower specificity of the IFN-γ test was at least in part due to undisclosed Mycobacterium microti infection in the TB-free cohort, which stimulates a positive purified protein derivative (PPD) response. The sensitivity of infection detection could be increased by combining two antibody tests, but even the use of all four antibody tests failed to detect all diseased alpacas. These antibody-negative alpacas were IFN-γ positive. We found that the maximum sensitivity could be achieved only by the combination of the IFN-γ test with two antibody tests in a “test package,” although this resulted in decreased specificity. The data from this evaluation of tests with defined sensitivity and specificity provide potential options for antemortem screening of SAC for TB in herd breakdown situations and could also find application in movement testing and tracing investigations. PMID:22914362

  14. Evaluation of gamma interferon and antibody tuberculosis tests in alpacas.

    PubMed

    Rhodes, Shelley; Holder, Tom; Clifford, Derek; Dexter, Ian; Brewer, Jacky; Smith, Noel; Waring, Laura; Crawshaw, Tim; Gillgan, Steve; Lyashchenko, Konstantin; Lawrence, John; Clarke, John; de la Rua-Domenech, Ricardo; Vordermeier, Martin

    2012-10-01

    We describe the performance of cell-based and antibody blood tests for the antemortem diagnosis of tuberculosis (TB) in South American camelids (SAC). The sensitivity and specificity of the gamma interferon (IFN-γ) release assay, two lateral flow rapid antibody tests (Stat-Pak and Dual Path Platform [DPP]), and two enzyme-linked immunosorbent assay (ELISA)-based antibody tests (Idexx and Enferplex) were determined using diseased alpacas from Mycobacterium bovis culture-confirmed breakdown herds and TB-free alpacas from geographical areas with no history of bovine TB, respectively. Our results show that while the sensitivities of the IFN-γ and antibody tests were similar (range of 57.7% to 66.7%), the specificity of the IFN-γ test (89.1%) was lower than those of any of the antibody tests (range of 96.4% to 97.4%). This lower specificity of the IFN-γ test was at least in part due to undisclosed Mycobacterium microti infection in the TB-free cohort, which stimulates a positive purified protein derivative (PPD) response. The sensitivity of infection detection could be increased by combining two antibody tests, but even the use of all four antibody tests failed to detect all diseased alpacas. These antibody-negative alpacas were IFN-γ positive. We found that the maximum sensitivity could be achieved only by the combination of the IFN-γ test with two antibody tests in a "test package," although this resulted in decreased specificity. The data from this evaluation of tests with defined sensitivity and specificity provide potential options for antemortem screening of SAC for TB in herd breakdown situations and could also find application in movement testing and tracing investigations.

  15. Evaluation of an Immunocapture-Agglutination Test (Brucellacapt) for Serodiagnosis of Human Brucellosis

    PubMed Central

    Orduña, Antonio; Almaraz, Ana; Prado, Ana; Gutierrez, M. Purificación; Garcia-Pascual, Agustina; Dueñas, Ana; Cuervo, Milagros; Abad, Ramon; Hernández, Beatriz; Lorenzo, Belen; Bratos, Miguel A.; Torres, Antonio Rodriguez

    2000-01-01

    We evaluated the validity and the usefulness of a new test for the diagnosis of human brucellosis based on an immunocapture-agglutination technique. A total of 315 sera from 82 patients with a diagnosis of brucellosis, 157 sera from patients in whom brucellosis was suspected but not confirmed, and 412 sera from people living in rural areas with endemic brucellosis were studied. The seroagglutination test (SAT), Coombs anti-Brucella test, and Brucellacapt test were evaluated. All the initial sera from the 82 patients proved to be positive in Brucellacapt and Coombs tests, while only 75 (91.4%) were positive in the SAT. If a ≥1/160 diagnostic threshold titer was defined for the Brucellacapt test, Coombs test, and SAT, the sensitivities were 95.1, 91.5, and 65.8%, respectively. Taking the same diagnostic threshold titer for the 157 sera from the unconfirmed but suspected patients, the specificities of the Brucellacapt, Coombs, and SAT were 81.5, 96.2, and 100%, respectively; for the 412 control sera, the specificities were 99.0, 99.8, and 100%. The diagnostic efficiency (area below the receiver operating characteristic curve) of Brucellacapt was 0.987852 (95% confidence interval [CI], 0.95109 to 0.99286), very similar to the diagnostic efficiency of the Coombs test (0.97611; 95% CI, 0.94781 to 0.99146) and higher than that of SAT (0.91013; 95% CI, 0.86649 to 0.94317). The results of the Brucellacapt test were compared with those of the Coombs test (correlation coefficient, 0.956; P = 0.000) and SAT (correlation coefficient, 0.866; P = 0.000). The study shows very good correlation between the Brucellacapt and Coombs tests, with a high concordance between titers obtained in the two tests. Nevertheless, lower correlation and concordance were found between the Brucellacapt and Coombs tests when the results for titers of ≥1/160 were compared (0.692; P = 0.000). In acute brucellosis, the Brucellacapt and Coombs tests render positive titers of ≥1/160. When the titers

  16. An integrated fiberoptic-microfluidic device for agglutination detection and blood typing.

    PubMed

    Ramasubramanian, Melur K; Alexander, Stewart P

    2009-02-01

    In this paper, an integrated fiberoptic-microfluidic device for the detection of agglutination for blood type cross-matching has been described. The device consists of a straight microfluidic channel through with a reacted RBC suspension is pumped with the help of a syringe pump. The flow intersects an optical path created by an emitter-received fiber optic pair integrated into the microfluidic device. A 650 nm laser diode is used as the light source and a silicon photodiode is used to detect the light intensity. The spacing between the tips of the two optic fibers can be adjusted. When fiber spacing is large and the concentration of the suspension is high, scattering phenomenon becomes the dominant mechanism for agglutination detection while at low concentrations and small spacing, optointerruption becomes the dominant mechanism. An agglutination strength factor (ASF) is calculated from the data. Studies with a variety of blood types indicate that the sensing method correctly identifies the agglutination reaction in all cases. A disposable integrated device can be designed for future implementation of the method for near-bedside pre-transfusion check.

  17. Paper diagnostic for instantaneous blood typing.

    PubMed

    Khan, Mohidus Samad; Thouas, George; Shen, Wei; Whyte, Gordon; Garnier, Gil

    2010-05-15

    Agglutinated blood transports differently onto paper than stable blood with well dispersed red cells. This difference was investigated to develop instantaneous blood typing tests using specific antibody-antigen interactions to trigger blood agglutination. Two series of experiments were performed. The first related the level of agglutination and the fluidic properties of blood on its transport in paper. Blood samples were mixed at different ratios with specific and nonspecific antibodies; a droplet of each mixture was deposited onto a filter paper strip, and the kinetics of wicking and red cell separation were measured. Agglutinated blood phase separated, with the red blood cells (RBC) forming a distinct spot upon contact with paper while the plasma wicked; in contrast, stable blood suspensions wicked uniformly. The second study analyzed the wicking and the chromatographic separation of droplets of blood deposited onto paper strips pretreated with specific and nonspecific antibodies. Drastic differences in transport occurred. Blood agglutinated by interaction with one of its specific antibodies phase separated, causing a chromatographic separation. The red cells wicked very little while the plasma wicked at a faster rate than the original blood sample. Blood agglutination and wicking in paper followed the concepts of colloids chemistry. The immunoglobin M antibodies agglutinated the red blood cells by polymer bridging, upon selective adsorption on the specific antigen at their surface. The transport kinetics was viscosity controlled, with the viscosity of red cells drastically increasing upon blood agglutination. Three arm prototypes were investigated for single-step blood typing.

  18. Evaluation of a new automated instrument for pretransfusion testing.

    PubMed

    Morelati, F; Revelli, N; Maffei, L M; Poretti, M; Santoro, C; Parravicini, A; Rebulla, P; Cole, R; Sirchia, G

    1998-10-01

    A number of automated devices for pretransfusion testing have recently become available. This study evaluated a fully automated device based on column agglutination technology (AutoVue System, Ortho, Raritan, NJ). Some 6747 tests including forward and reverse ABO group, Rh type and phenotype, antibody screen, autocontrol, and crossmatch were performed on random samples from 1069 blood donors, 2063 patients, and 98 newborns and cord blood. Also tested were samples from 168 immunized patients and 53 donors expressing weak or variant A and D antigens. Test results and technician times required for their performance were compared with those obtained by standard methods (manual column agglutination technology, slide, semiautomatic handler). No erroneous conclusions were found in regard to the 5028 ABO group and Rh type or phenotype determinations carried out with the device. The device rejected 1.53 percent of tests for sample inadequacy. Of the remaining 18 tests with discrepant results found with the device and not confirmed with the standard methods, 6 gave such results because of mixed-field reactions, 10 gave negative results with A2 RBCs in reverse ABO grouping, and 2 gave very weak positive reactions in antibody screening and crossmatching. In the samples from immunized patients, the device missed one weak anti-K, whereas standard methods missed five weak antibodies. In addition, 48, 34, and 31 of the 53 weak or variant antigens were detected by the device, the slide method, and the semiautomated handler, respectively. Technician time with the standard methods was 1.6 to 7 times higher than that with the device. The technical performance of the device compared favorably with that of standard methods, with a number of advantages, including in particular the saving of technician time. Sample inadequacy was the most common cause of discrepancy, which suggests that standardization of sample collection can further improve the performance of the device.

  19. Development of a fluorescent antibody virus neutralisation test (FAVN test) for the quantitation of rabies-neutralising antibody.

    PubMed

    Cliquet, F; Aubert, M; Sagné, L

    1998-03-01

    A microtest named the FAVN test (fluorescent antibody virus neutralisation test), which is an adaptation of the original rapid fluorescent focus inhibition test (RFFIT) has been developed and evaluated. One hundred percent specificity was estimated using 414 sera from dogs sampled in rabies-free areas or from non-vaccinated animals. The accuracy as determined by the agreement between observed and expected values using sera of known titres was satisfactory. Serum samples from unvaccinated and vaccinated dogs (using sera with titres near 0.5 IU/ml) were assayed for rabies antibody by the FAVN test, the RFFIT and the mouse neutralisation test (MNT): comparative results obtained on the same sera with the three tests showed good agreement. Furthermore, distinguishing negative sera from positive sera with low titres is much easier with the FAVN test than with the RFFIT.

  20. Detection of antibodies reacting with the antithetical duffy blood group antigens Fy(a) and Fy(b) using recombinant fusion proteins containing the duffy extracellular domain.

    PubMed

    Sheffield, William P; Bhakta, Varsha; Branch, Donald R; Denomme, Gregory A

    2006-12-01

    Detecting blood group-specific antibodies in patient sera is essential to the management of blood transfusions or pregnancies. We produced the antithetical forms of the 65 amino acid extracellular domain (ECD) of the Duffy (Fy) blood group protein fused to glutathione sulfotransferase (GST): GST-Fy(a); and GST-Fy(b), differing only in Gly or Asp at position 44, respectively. The purified recombinant proteins were recognized more effectively by reference polyclonal or monoclonal antibodies than the antithetical Fy specificity by either ELISA or immunoblotting. Combined immunoblot and ELISA tests performed at 1:200 dilutions of sera using the recombinant proteins gave results in agreement with undiluted sera and agglutination for 17/19 alloimmunized patients. At 1:200, agglutination detected anti-Fy(a) or anti-Fy(b) in only three of 12 samples that were positive by ELISA. Recombinant ECD-Fy proteins are suitable and sensitive reagents for the detection of anti-Fy that use technology amenable to automation and/or miniaturization and avoid the need for intact red cells.

  1. Kinetic of antigent-antibody reactions with scattering method

    NASA Astrophysics Data System (ADS)

    Bilyi, Olexander I.; Kiselyov, Yevgen M.; Novikov, Volodymyr P.

    2001-07-01

    The immune reactions of interaction antigen-antibody represent specific effect of an antigene with an antibody, which outcome are the complex immune aggregates forming precipitate in case of a soluble antigene, or agglutinate in case of a corpuscular antigene. Immunological methods which uses in the quality of carrier protein latex's polymeric microspheresis, gained name and method latex agglutination. Polymeric microspheresis have the array of advantages before biological carries, which consist in the opportunity of the variation of attributes surface and size microspheresis in the broad band of meanings with the preservation of narrow distribution particles behind measurements, the putting of functional groups, necessary for bunch with ligand on stage their synthesis, in ragidity at storage. The quantitative evaluation of parameters of a response of interaction antigen-antibody in immunology is possible by optical methods on a measurement of a modification of intensity of a light stream of a solution in an outcome of a course of a reaction. Concentration of immune complexes determine both on slacking a taking place stream of light, and on a modification of intensity of a stream of light scattering suspended particles in a solution. The process light scattering by colloidal aggregates are formed from suspension microspheresis with adsorbed on their surface protein is described. In report the physics principle of registration immune reaction by light scattering methods is concerned. The results of the effectiveness latex's preparation created on basis of the polymeric carries is described.

  2. Seroprevalence of Brucella antibodies in camels in Katsina State, Nigeria.

    PubMed

    Salisu, U S; Kudi, C A; Bale, J O O; Babashani, M; Kaltungo, B Y; Saidu, S N A; Asambe, A; Baba, A Y

    2017-06-01

    A cross-sectional study was carried out to determine the status of Brucella infection in one-humped (Dromedary) camels in the North and Central senatorial districts of Katsina State, Nigeria. Nine hundred and eighty serum samples from live and slaughtered camels were tested. Modified Rose Bengal plate test (RBPT) and serum agglutination test (SAT) with ethylenediaminetetraacetic acid, (EDTA) were used as screening and standard tests, respectively. The prevalence of Brucella antibodies were 110 (11.2%) and 103 (10.5%) for RBPT and SAT, respectively. Of the 472 and 508 serum samples tested from the herds and abattoirs, respectively, 63 (13.3%) and 47 (9.3%) were positive by RBPT while 62 (13.1%) and 41 (8.1%) were positive by SAT, respectively. Based on the results, it was concluded that Brucella antibodies were present in camels in the study area. Poor management practices and mixing of camels with other species of livestock as well as unrestricted movement of camels were proposed to be the reasons for the prevalence of the disease in the study area. In view of the public health importance of the disease, it is recommended that there is the need to develop a strategic plan to decrease spread of brucellosis in the study area.

  3. 21 CFR 866.5090 - Antimitochondrial antibody immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5090 Antimitochondrial antibody immunological test system. (a) Identification. An... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antimitochondrial antibody immunological test...

  4. Prevalence of antibodies against Toxoplasma gondii in polar bears (Ursus maritimus) from Svalbard and East Greenland.

    PubMed

    Oksanen, A; Asbakk, K; Prestrud, K W; Aars, J; Derocher, A E; Tryland, M; Wiig, O; Dubey, J P; Sonne, C; Dietz, R; Andersen, M; Born, E W

    2009-02-01

    Serum samples from 419 polar bears (Ursus maritimus) from Svalbard and the Barents Sea (collected 1990-2000) and 108 polar bears from East Greenland (collected 1999-2004) were assayed for antibodies against Toxoplasma gondii using the modified agglutination test. Antibody prevalences were 3.6% among cubs dependent on their mothers and 21.4% among subadults and adults. Among subadults and adults there was an interaction between population and sex, with similar prevalences among females (Svalbard = 19.5%, Greenland = 18.0%), but a high frequency among Svalbard males (28.7%) as compared to Greenland males (5.8%). The pattern was also significant after correcting for differences in age distribution. The sex-population interaction term is believed to be connected to area- and sex-specific feeding ecology. The prevalences of antibodies against T. gondii in Svalbard and Greenland were high compared to previously reported findings in polar bears from Russian and Alaskan areas.

  5. Utility of HLA Antibody Testing in Kidney Transplantation

    PubMed Central

    Konvalinka, Ana

    2015-01-01

    HLA antigens are polymorphic proteins expressed on donor kidney allograft endothelium and are critical targets for recipient immune recognition. HLA antibodies are risk factors for acute and chronic rejection and allograft loss. Solid-phase immunoassays for HLA antibody detection represent a major advance in sensitivity and specificity over cell-based methods and are widely used in organ allocation and pretransplant risk assessment. Post-transplant, development of de novo donor–specific HLA antibodies and/or increase in donor-specific antibodies from pretransplant levels are associated with adverse outcomes. Although single antigen bead assays have allowed sensitive detection of recipient HLA antibodies and their specificities, a number of interpretive considerations must be appreciated to understand test results in clinical and research contexts. This review, which is especially relevant for clinicians caring for transplant patients, discusses the technical aspects of single antigen bead assays, emphasizes their quantitative limitations, and explores the utility of HLA antibody testing in identifying and managing important pre- and post-transplant clinical outcomes. PMID:25804279

  6. Comparison of commercial ELISA tests for the detection of Toxoplasma antibodies in the meat juice of naturally infected pigs.

    PubMed

    Felin, Elina; Näreaho, Anu; Fredriksson-Ahomaa, Maria

    2017-04-30

    Toxoplasmosis is a globally distributed protozoal zoonosis. Pigs are considered an important reservoir of Toxoplasma gondii and pork a major infection source of human toxoplasmosis. ELISA methods are commonly used diagnostic tools for detecting Toxoplasma infections. They are also used for slaughterhouse-based serological monitoring of toxoplasmosis in pigs to identify positive farms. The methods used are non-standardised with varying sensitivity and specificity. In our study, four commercial ELISA tests for the detection of Toxoplasma antibodies in the meat juice of slaughter pigs were compared with a modified agglutination test (MAT) as a reference. The cut-off values of the ELISA tests provided by the manufacturer varied between 0.20 and 0.50, and clearly influenced prevalence. The sensitivity of tests I, II and III varied between 96.4 and 78.6. Sensitivity was unacceptably low (3.6) for test IV (cut-off=0.30). Tests I, II and III had the highest accuracy and the best agreement with the reference test when a cut-off of 0.30 was used. Test II and III showed very good agreement (K=0.92 and 0.84, respectively) with the MAT. A very strong correlation (Pearson correlation >0.89) was observed between the S/P values of tests I, II and III. Our results demonstrate that the test and cut-off value used influence the results of the apparent seroprevalence studies. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. A rare case of anti-jk3 antibody detected on pre-transfusion investigation.

    PubMed

    Yousuf, Rabeya; Abdul Aziz, Suria; Yusof, Nurasyikin; Leong, Chooi-Fun

    2014-09-01

    We report a 47-year-old Malay lady, para 4 + 1, with known medical history of hypertension whom presented at Emergency Department with severe anaemia, most likely secondary to menorrhagia caused by uterine fibroids. Her haemoglobin was 5.5 g/dl and she was transfused with three units of packed cell without any adverse reaction, her haemoglobin level increased to 9.8 g/dl. She was then planned for total abdominal hysterectomy and bilateral salpingo-oophorectomy later. Four months later when she came for the elective surgery, her pre transfusion investigations showed blood group as B Rh D positive, with a probable R1R1 phenotype. Her antibody screening was positive in all the three panel cells. Further testings showed a negative Direct Coomb's test and negative autocontrol, antibody identification showed pan-agglutination reaction on all 11 panel cells with enzyme enhancement. Patient's red cell phenotype was Jk(a-b-). Anti-Jk3 was suspected and further confirmed in the reference laboratory by phenotyping as well as negative urea lysis test. This case report highlights an extremely rare but clinically significant anti-JK3 antibody detected during pretransfusion testing. This phenotype is rare in the white population, more commonly seen in various polynesians. Increased awareness among the blood bank personnel regarding the variability of the blood group phenotype and the capricious nature of the Kidd antibodies may contribute to the better management of these patients.

  8. STUDIES OF ANTIGENIC DIFFERENCES AMONG STRAINS OF INFLUENZA A BY MEANS OF RED CELL AGGLUTINATION

    PubMed Central

    Hirst, George K.

    1943-01-01

    A study of cross inhibition tests among strains of influenza A virus and their antisera showed that the results obtained were subject to a certain amount of variation due to the red cells, the virus suspensions, and the ferret antisera employed. Methods have been demonstrated for handling the data obtained from such tests, so that these variables were corrected or avoided, making it possible to use the agglutination technique for antigenic comparisons. The antigenic pattern of eighteen strains of influenza A virus, obtained from the 1940–41 epidemic in the United States, has been compared by means of agglutination inhibition tests with ferret antisera. No significant antigenic differences were found among sixteen of these strains (all isolated from throat washings by the inoculation of chick embryos) although they were obtained from individuals in widely separated regions of the country. Two strains, from cases occurring early in the epidemic and isolated from throat washings by ferret and mouse passage, showed a slight but significant strain difference from the other strains and from each other. One of the 1940–41 strains on cross test resembled the PR8 strain more closely than any other stock strain tested. PMID:19871338

  9. Humoral responses in human organ transplantation

    PubMed Central

    Waller, Marion; Pierce, J. C.; Moncure, C. W.; Hume, D. M.

    1972-01-01

    The plasmas of fifteen patients undergoing organ transplantation were serially tested for a variety of humoral antibodies. The antibodies studied were those which usually reflect covert immunologic events, i.e. the antiglobulins (rheumatoid factors and serum agglutinators), heterophile antibodies and typical and atypical isoantibodies. Although the isoantibodies and the heterophile antibodies were not significantly stimulated by organ transplantation, the administration of ALG (horse antilymphocyte globulin) invariably led to the presence of antihorse globulin antibodies. Three patients were Rh negative and received organs from Rh-positive donors. However, only one of the patients responded with anti-Rh antibodies, but these antibodies exceeded in titre the anti-Rh antibodies usually observed following intentional immunization of normal volunteers. The most startling observation was the significant increase in titres of the serum agglutinators in eight of the patients. These observations suggest that the antigen–antibody complexes associated with chronic rejection may stimulate the production of the serum agglutinators. PMID:4625156

  10. Case report and literature review: transient Inab phenotype and an agglutinating anti-IFC in a patient with a gastrointestinal problem.

    PubMed

    Yazer, Mark H; Judd, W John; Davenport, Robertson D; Dake, Louann R; Lomas-Francis, Christine; Hue-Roye, Kim; Powell, Vivien; Reid, Marion

    2006-09-01

    The Inab phenotype is a rare deficiency of all Cromer antigens. These antigens are carried on the decay-accelerating factor (DAF, CD55) molecule that is attached to the red blood cell (RBC) membrane by a glycosylphosphatidylinositol (GPI) anchor. Although typically inherited, an acquired and transient form of the Inab phenotype also exists. A patient with the triad of transient Inab phenotype, a direct-agglutinating anti-IFC, and gastrointestinal (GI) abnormalities is reported. An 18-month-old boy with gastroesophageal reflux disease requiring a feeding tube, milk and soy intolerance, and severe growth retardation, as well as vision and hearing deficits from cytomegalovirus infection, was identified when pretransfusion testing revealed a potent panagglutinin (titer > 2000 at 4 degrees C). This antibody did not react with Dr(a-) and IFC RBCs, and the autocontrol was negative. The patient's RBCs lacked CD55 by flow cytometric techniques but had normal levels of CD59 and antigens such as Yt(a) and Emm, carried on GPI-linked proteins, thus excluding paroxysmal nocturnal hemoglobinuria. Several months after initial detection, the anti-IFC was virtually undetectable and his cells reacted weakly with anti-IFC, anti-Dr(a), and anti-CD55. RBCs from the propositus' parents and brother demonstrated normal CD55 and CD59 expression. This is the first example of a direct-agglutinating anti-IFC. The cause of the transient depression in CD55 protein (and thus Cromer system antigens) and appearance of anti-IFC remains unknown, as does the relationship between the patient's GI system abnormalities and these serologic findings.

  11. Development and evaluation of an enzyme-labeled antibody test for the rapid detection of hog cholera antibodies

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

    Saunders, G.C.

    1977-01-01

    A rapid enzyme-labeled antibody (ELA) microtechnique for the screening of swine for hog cholera antibodies was developed and evaluated with a blind study, using a 640-sample hog cholera serum bank. The total time to run a group of 22 samples was approximately 1 hour. The ELA test results correlated >99% with hog cholera serum-neutralization test results on the same serums. Test results also indicated that the ELA test shares with the hog cholera serum-neutralization test the problem of cross reactions between the antibodies of hog cholera and bovine viral diarrhea.

  12. Antibodies to Toxoplasma gondii and Leishmania spp. in domestic cats from Luanda, Angola.

    PubMed

    Lopes, Ana Patrícia; Oliveira, Ana Cristina; Granada, Sara; Rodrigues, Filipa T; Papadopoulos, Elias; Schallig, Henk; Dubey, Jitender P; Cardoso, Luís

    2017-05-30

    Toxoplasma gondii and Leishmania spp. are zoonotic protozoa of importance to animal and public health. The present study aimed to assess for the first time the seroprevalence of these zoonotic parasites in a domestic feline population living in Luanda, Angola. One hundred and two cats were sampled at a veterinary medical centre, from May 2014 to February 2016. The age of the cats ranged from 2.5 to 143 months (median: 12 months; interquartile range: 7.5-24). Serum samples were tested for immunoglobulin (Ig) G antibodies to T. gondii at two-fold dilutions of 1:20 to 1:2560 with a modified agglutination test (MAT) commercial kit. The direct agglutination test (DAT) for titration of IgG antibodies specific to Leishmania spp. used a standard freeze-dried antigen at a concentration of 5×10 7 promastigotes per milliliter, following a predefined protocol. Two-fold dilution series ranging from 1:25 to 1:800 were tested, with a cut-off titre of 100 chosen for seropositivity. Four out of 102 cats (3.9%; 95% confidence interval [CI]: 1.1-9.7) had antibodies to T. gondii: one had a titer of 20, one a titer of 160, and two had a titer≥2560. No cat (0.0%; CI: 0.0-3.5) was found seropositive for Leishmania spp. A statistically significant difference was found between T. gondii seroprevalence and Leishmania spp. seroprevalence (p=0.043). The odds of a cat being seropositive to T. gondii increased by an average factor of 1.58 for each 1-year increase in age (p=0.003). The sampled cats were well-cared animals and may not represent the overall feline population of Angola at the national and city levels. The fact that only 12 out of the 102 sampled cats ate or had access to raw or undercooked meat and/or viscera may have reduced the likelihood of finding seropositive results. Under these circumstances, additional studies, including a larger number of cats, are necessary for a more comprehensive assessment of the zoonotic risk posed by these animals in Angola. Copyright © 2017

  13. Antibody testing against canine coronavirus by immunoperoxidase plaque staining.

    PubMed

    Soma, T; Hara, M; Ishii, H; Yamamoto, S

    2001-05-01

    The application of the immunoperoxidase (IP) plaque staining procedure (IP test) to the diagnosis of canine coronavirus (CCV) infection was investigated. The IP test did not react with sera from either 15 specific pathogen-free (SPF) dogs or 7 SPF dogs immunized with a multivalent vaccine, including canine parvovirus type 2, canine distemper virus, canine adenovirus type 2, and canine parainfluenza virus. To compare the IP test with the neutralizing test (NT), sera from 240 healthy dogs and from 3 experimentally CCV-infected dogs were examined. All 60 sera positive for NT antibody were positive for IP antibody, and all 180 sera negative for NT antibody were negative for IP antibody in the healthy dogs. The IP titres showed similar changes with time after CCV inoculation to those of the NT titres in the experimentally infected dogs. These findings indicate that the IP test specifically detected anti-CCV antibodies. When the IP test and NT were compared in dogs with diarrhoeic signs. 2.1% of 48 sera and 20.3% of 74 sera, which were all negative for NT antibody, were positive for IP antibody in the dogs of under one year of age and at least one year of age, respectively. The difference between the IP and NT titres (log10 [reciprocal of IP titre] log10 [reciprocal of NT titre]) for the diarrhoeic dogs of under one year of age (2.350 +/- 0.931) was significantly larger than that for the healthy dogs (0.982 +/- 0.447) (p<0.0001), the NT titre being negative or very low, despite a high IP titre in many diarrhoeic dogs. Hence, the IP test is more able to detect anti-CCV antibodies, especially in dogs showing clinical signs. The IP-positivity rate was significantly higher in the diarrhoeic dogs of under one year of age (48.7%) than in the healthy dogs (25.0%) (chi2 = 19.844, p<0.0001), suggesting that CCV may contribute to diarrhoea in many juvenile dogs.

  14. Mutant botrocetin-2 inhibits von Willebrand factor-induced platelet agglutination.

    PubMed

    Matsui, T; Hori, A; Hamako, J; Matsushita, F; Ozeki, Y; Sakurai, Y; Hayakawa, M; Matsumoto, M; Fujimura, Y

    2017-03-01

    Essentials Botrocetin-2 (Bot2) binds to von Willebrand factor (VWF) and induces platelet agglutination. We identified Bot2 residues that are required for binding to VWF and glycoprotein (GP) Ib. We produced a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Mutant Bot2 could be used as a potential anti-thrombotic reagent to block VWF-GPIb interaction. Background Botrocetin-2 (Bot2) is a botrocetin-like protein composed of α and β subunits that have been cloned from the snake Bothrops jararaca. Bot2 binds specifically to von Willebrand factor (VWF), and the complex induces glycoprotein (GP) Ib-dependent platelet agglutination. Objectives To exploit Bot2's VWF-binding capacity in order to attempt to create a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Methods and Results Several point mutations were introduced into Bot2 cDNA, and the recombinant protein (recombinant Bot2 [rBot2]) was purified on an anti-botrocetin column. The mutant rBot2 with either Ala at Asp70 in the β subunit (Aspβ70Ala), or Argβ115Ala and Lysβ117Ala, showed reduced platelet agglutination-inducing activity. rBot2 with Aspβ70Ala showed little binding activity towards immobilized VWF on an ELISA plate, whereas rBot2 with Argβ115Ala/Lysβ117Ala showed reduced binding activity towards GPIb (glycocalicin) after forming a complex with VWF. rBot2 point-mutated to oppositely charged Glu at both Argβ115 and Lysβ117 showed normal binding activity towards VWF but no platelet-agglutinating activity. Furthermore, this doubly mutated protein inhibited ristocetin-induced or high shear stress-induced platelet aggregation, and restrained thrombus formation under flow conditions. Conclusions Asp70 in the β subunit of botrocetin is important for VWF binding, and Arg115 and Lys117 in the β subunit are essential for interaction with GPIb. Doubly mutated rBot2, with Argβ115Glu and Lysβ117Glu, repels GPIb and might have potential as an antithrombotic reagent that

  15. The Staphylococcus aureus ArlRS Two-Component System Is a Novel Regulator of Agglutination and Pathogenesis

    PubMed Central

    Walker, Jennifer N.; Crosby, Heidi A.; Spaulding, Adam R.; Salgado-Pabón, Wilmara; Malone, Cheryl L.; Rosenthal, Carolyn B.; Schlievert, Patrick M.; Boyd, Jeffrey M.; Horswill, Alexander R.

    2013-01-01

    Staphylococcus aureus is a prominent bacterial pathogen that is known to agglutinate in the presence of human plasma to form stable clumps. There is increasing evidence that agglutination aids S. aureus pathogenesis, but the mechanisms of this process remain to be fully elucidated. To better define this process, we developed both tube based and flow cytometry methods to monitor clumping in the presence of extracellular matrix proteins. We discovered that the ArlRS two-component system regulates the agglutination mechanism during exposure to human plasma or fibrinogen. Using divergent S. aureus strains, we demonstrated that arlRS mutants are unable to agglutinate, and this phenotype can be complemented. We found that the ebh gene, encoding the Giant Staphylococcal Surface Protein (GSSP), was up-regulated in an arlRS mutant. By introducing an ebh complete deletion into an arlRS mutant, agglutination was restored. To assess whether GSSP is the primary effector, a constitutive promoter was inserted upstream of the ebh gene on the chromosome in a wildtype strain, which prevented clump formation and demonstrated that GSSP has a negative impact on the agglutination mechanism. Due to the parallels of agglutination with infective endocarditis development, we assessed the phenotype of an arlRS mutant in a rabbit combined model of sepsis and endocarditis. In this model the arlRS mutant displayed a large defect in vegetation formation and pathogenesis, and this phenotype was partially restored by removing GSSP. Altogether, we have discovered that the ArlRS system controls a novel mechanism through which S. aureus regulates agglutination and pathogenesis. PMID:24367264

  16. Antibodies to H5 subtype avian influenza virus and Japanese encephalitis virus in northern pintails (Anas acuta) sampled in Japan

    USGS Publications Warehouse

    Ramey, Andy M.; Spackman, Erica; Yeh, Jung-Yong; Fujita, Go; Konishi, Kan; Reed, John A.; Wilcox, Benjamin R.; Brown, Justin D.; Stallknecht, David E.

    2013-01-01

    Blood samples from 105 northern pintails (Anas acuta) captured on Hokkaido, Japan were tested for antibodies to avian influenza virus (AIV), Japanese encephalitis virus (JEV), and West Nile virus (WNV) to assess possible involvement of this species in the spread of economically important and potentially zoonotic pathogens. Antibodies to AIV were detected in 64 of 105 samples (61%). Of the 64 positives, 95% and 81% inhibited agglutination of two different H5 AIV antigens (H5N1 and H5N9), respectively. Antibodies to JEV and WNV were detected in five (5%) and none of the samples, respectively. Results provide evidence for prior exposure of migrating northern pintails to H5 AIV which couldhave implications for viral shedding and disease occurrence. Results also provide evidence for limited involvement of this species in the transmission and spread of flaviviruses during spring migration.

  17. Cross-sectional study of serum antibodies against Sarcocystis neurona in cats tested for antibodies against Toxoplasma gondii.

    PubMed

    Rossano, Mary G; Murphy, Alice J; Vrable, Ruth A; Vanzo, Nicole E; Lewis, Stacy K; Sheline, Katherine D; Kaneene, John B; Mansfield, Linda S

    2002-08-15

    To determine apparent seroprevalence of antibodies against Sarcocystis neurona in a population of domestic cats previously tested for antibodies against Toxoplasma gondii. Cross-sectional study. Serum from 196 domestic cats. Banked serum samples submitted to the Michigan State University Animal Health Diagnostic Laboratory for T. gondii diagnostic testing were tested for antibodies against S. neurona by use of an indirect fluorescent antibody (IFA) test and a western blot test. Submission records were analyzed to determine descriptive statistics and test for associations between positive results of a test for S. neurona and other variables in the data set. 10 of 196 (5%) samples yielded positive results for antibodies against S. neurona by use of western blot analysis, whereas 27 samples yielded positive results by use of the IFA. No association was found between S. neurona western blot test results and T. gondii test results, age, sex, or the reason for T. gondii testing. The S. neurona IFA titer was positively and significantly associated with positive results of western blot analysis. Domestic cats are not likely to play a substantial role as intermediate hosts in the natural life cycle of S. neurona. Results indicate that natural infection of domestic cats may occur, and small animal practitioners should be aware of this fact when evaluating cats with neurologic disease. The S. neurona IFA test had lower specificity than western blot analysis.

  18. Soybean extracts facilitate bacterial agglutination and prevent biofilm formation on orthodontic wire.

    PubMed

    Lee, Heon-Jin; Kwon, Tae-Yub; Kim, Kyo-Han; Hong, Su-Hyung

    2014-01-01

    Soybean is an essential food ingredient that contains a class of organic compounds known as isoflavones. It is also well known that several plant agglutinins interfere with bacterial adherence to smooth surfaces. However, little is known about the effects of soybean extracts or genistein (a purified isoflavone from soybean) on bacterial biofilm formation. We evaluated the effects of soybean (Glycine max) extracts, including fermented soybean and genistein, on streptococcal agglutination and attachment onto stainless steel orthodontic wire. After cultivating streptococci in biofilm medium containing soybean extracts and orthodontic wire, the viable bacteria attached to the wire were counted. Phase-contrast microscopy and scanning electron microscopy (SEM) analyses were conducted to evaluate bacterial agglutination and attachment. Our study showed that soybean extracts induce agglutination between streptococci, which results in bacterial precipitation. Conversely, viable bacterial counting and SEM image analysis of Streptococcus mutans attached to the orthodontic wire show that bacterial attachment decreases significantly when soybean extracts were added. However, there was no significant change in pre-attached S. mutans biofilm in response to soybean. A possible explanation for these results is that increased agglutination of planktonic streptococci by soybean extracts results in inhibition of bacterial attachment onto the orthodontic wire.

  19. Klebsiella pneumoniae type 3 fimbriae agglutinate yeast in a mannose-resistant manner.

    PubMed

    Stahlhut, Steen G; Struve, Carsten; Krogfelt, Karen A

    2012-03-01

    The ability of bacterial pathogens to express different fimbrial adhesins plays a significant role in virulence. Thus, specific detection of fimbrial expression is an important task in virulence characterization and epidemiological studies. Most clinical Klebsiella pneumoniae isolates express type 1 and type 3 fimbriae, which are characterized by mediation of mannose-sensitive agglutination of yeast cells and agglutination of tannic acid-treated ox red blood cells (RBCs), respectively. It has been observed that K. pneumoniae isolates agglutinate yeast cells and commercially available sheep RBCs in a mannose-resistant manner. Thus, this study was initiated to identify the adhesin involved. Screening of a mutant library surprisingly revealed that the mannose-resistant agglutination of yeast and sheep RBCs was mediated by type 3 fimbriae. Specific detection of type 1 fimbriae expression in K. pneumoniae was feasible only by the use of guinea pig RBCs. This was further verified by the use of isogenic fimbriae mutants and by cloning and expressing K. pneumoniae fimbrial gene clusters in Escherichia coli. Yeast agglutination assays are commonly used to detect type 1 fimbriae expression but should not be used for bacterial species able to express type 3 fimbriae. For these species, the use of guinea pig blood for specific type 1 fimbriae detection is essential. The use of commercially available sheep RBCs or yeast is an easy alternative to traditional methods to detect type 3 fimbriae expression. Easy and specific detection of expression of type 1 and type 3 fimbriae is essential in the continuous characterization of these important adhesive virulence factors present in members of the Enterobacteriaceae.

  20. Comparison of the H7 latex agglutination test with a fliCh7 real-time PCR assay for confirmation of the H type of Escherichia coli O157:H7

    USDA-ARS?s Scientific Manuscript database

    Escherichia coli O157:H7 is a food-borne pathogen that causes hemorrhagic colitis and hemolytic uremic syndrome. Positive identification of E. coli O157:H7 is made using biochemical tests and latex agglutination using specific antisera. However, under certain conditions, some E. coli O157:H7 isolate...

  1. 21 CFR 864.9175 - Automated blood grouping and antibody test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes (red... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated blood grouping and antibody test system...

  2. 21 CFR 864.9175 - Automated blood grouping and antibody test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes (red... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated blood grouping and antibody test system...

  3. 21 CFR 864.9175 - Automated blood grouping and antibody test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes (red... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated blood grouping and antibody test system...

  4. 21 CFR 864.9175 - Automated blood grouping and antibody test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes (red... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated blood grouping and antibody test system...

  5. 21 CFR 864.9175 - Automated blood grouping and antibody test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Manufacture Blood and Blood Products § 864.9175 Automated blood grouping and antibody test system. (a) Identification. An automated blood grouping and antibody test system is a device used to group erythrocytes (red... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated blood grouping and antibody test system...

  6. Are the Major Agglutinative Languages Genetically Related?

    ERIC Educational Resources Information Center

    Hakola, H. P. A.

    1989-01-01

    Examination of accidental CVC and CV correspondences among languages representing 5 large families of agglutinative languages found that comparison pairs had much more similarity between basic 100-word vocabularies than would have been possible by mere chance, supporting the hypothesis that those 5 language families were mutually related.…

  7. Isolation, in vitro culture, ultrastructure study, and characterization by lectin-agglutination tests of Phytomonas isolated from tomatoes (Lycopersicon esculentum) and cherimoyas (Anona cherimolia) in southeastern Spain.

    PubMed

    Sanchez-Moreno, M; Fernandez-Becerra, C; Mascaro, C; Rosales, M J; Dollet, M; Osuna, A

    1995-01-01

    Plants of Lycopersicon esculentum (grown in greenhouses) and Anona cherimolia cultivated in southeastern Spain were examined for the presence of trypanosomatid flagellates. Kinetoplastid protozoa were found in the fruits but not in the phloem or other plant tissues. Parasites were detected from the onset of fruiting. Isolates were detected from the onset of fruiting. Isolates were adapted to in vitro culturing in monophase media. The form and the structural organization was studied by scanning and transmission electron microscopy. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. In tomatoes experimentally inoculated with flagellates cultivated in vitro, we observed that the parasites did not lose their infectious capacity. Three strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia (E. characias and E. hyssopifolia) and from Cocos nucifera, were compared with our isolates by lectin-agglutination tests. Our isolates were different from the two strains isolated from Euphorbia, but with this technique we could not differentiate our isolates from those of the coconut, nor could we differentiate between the isolates, their ultrastructural similarity together with their similar behavior in the lectin-agglutination test suggesting that these isolates have a common origin.

  8. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5120 Antismooth muscle antibody immunological test system. (a) Identification. An antismooth... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Antismooth muscle antibody immunological test...

  9. Clinical Utility of Acetylcholine Receptor Antibody Testing in Ocular Myasthenia Gravis.

    PubMed

    Peeler, Crandall E; De Lott, Lindsey B; Nagia, Lina; Lemos, Joao; Eggenberger, Eric R; Cornblath, Wayne T

    2015-10-01

    The sensitivity of acetylcholine receptor (AChR) antibody testing is thought to be lower in ocular myasthenia gravis (OMG) compared with generalized disease, although estimates in small-scale studies vary. There is little information in the literature about the implications of AChR antibody levels and progression from OMG to generalized myasthenia gravis. To test the hypothesis that serum AChR antibody testing is more sensitive in OMG than previously reported and to examine the association between AChR antibody levels and progression from OMG to generalized myasthenia gravis. A retrospective, observational cohort study was conducted of 223 patients (mean [SD] age, 59.2 [16.4] years; 139 [62.3%] male) diagnosed with OMG between July 1, 1986, and May 31, 2013, at 2 large, academic medical centers. Baseline characteristics, OMG symptoms, results of AChR antibody testing, and progression time to generalized myasthenia gravis (if this occurred) were recorded for each patient. Multiple logistic regression was used to measure the association between all clinical variables and antibody result. Kaplan-Meier survival analysis was performed to examine time to generalization. Among the 223 participants, AChR antibody testing results were positive in 158 participants (70.9%). In an adjusted model, increased age at diagnosis (odds ratio [OR], 1.03; 95% CI, 1.01-1.04; P = .007) and progression to generalized myasthenia gravis (OR, 2.92; 95% CI, 1.18-7.26; P = .02) were significantly associated with positive antibody test results. Women were less likely to have a positive antibody test result (OR, 0.36; 95% CI, 0.19-0.68; P = .002). Patients who developed symptoms of generalized myasthenia gravis had a significantly higher mean (SD) antibody level than those who did not develop symptoms of generalized myasthenia gravis (12.7 [16.5] nmol/L vs 4.2 [7.9] nmol/L; P = .002). We demonstrate a higher sensitivity of AChR antibody testing than previously reported in the

  10. [Influence of S-nitrosoglutathione on agglutination and nitric oxide concentration in frozen platelets].

    PubMed

    Wu, Tao; Liu, Jing-Han; Li, Hui; Zhou, Wu; Wang, Shu-Ying

    2012-04-01

    The aim of this study was to investigate the influence of S-nitrosoglutathione (GSNO) on agglutination and nitric oxide (NO) concentration in frozen platelets. The agglutination of platelets was detected by using platelet agglutination apparatus, the level of NO in platelets was detected by the nitrate enzyme reduction method. The results showed that the rates of agglutination in freeze platelets and frozen platelets treated with GSNO were (35.47 ± 2.93) and (24.43 ± 3.07), which were significantly lower than that in fresh liquid platelets (63.44 ± 2.96). The level of NO concentration in frozen platelets was (22.16 ± 6.38), which was significantly lower than that in fresh liquid platelets (31.59 ± 16.88). The level of NO concentration in frozen platelets treated with GSNO was (45.64 ± 6.31), which was significantly higher than that in fresh liquid platelets (P < 0.01). It is concluded that GSNO increases the concentration of NO in frozen platelets, inhibits platelet activation and maintains platelet function, thus GSNO can be used as a frozen protective agent.

  11. A systematic review on the microscopic agglutination test seroepidemiology of bovine leptospirosis in Latin America.

    PubMed

    Pinto, Priscila da Silva; Libonati, Hugo; Penna, Bruno; Lilenbaum, Walter

    2016-02-01

    The diagnosis of leptospirosis commonly relies on serology, which has three issues that are referred: the sampling, the antigen panel, and the cutoff point. We propose a systematic review of the bovine leptospirosis in Latin America, in order to provide a better understanding of the evolution of the research and of the seroepidemiology of bovine leptospirosis in that region. Internet databases were consulted over the year of 2014. Inclusion criteria for analysis included serosurvey using microscopic agglutination test (MAT), a relevant number of animals, the presence in the antigen panel of at least one representant of serogroup Sejroe, and a cutoff point of ≥100. A total of 242 articles that referred to cattle, leptospir*, and one region of Latin America was found. Only 105 articles regarding to serosurveys using MAT were found in several countries, and 61 (58.1 %) met all the inclusion criteria. In conclusion, this systematic review demonstrated a high prevalence of the infection (75.0 % at herd level and 44.2 % at animal level), with predominance of strains of serogroup Sejroe (80.3 %). It was evident that there is the necessity of more studies in several countries, as well as the need for greater standardization in studies, especially with regard to the adopted cutoff point at serological tests.

  12. Seroprevalence of Neospora caninum and Toxoplasma gondii antibodies in the South American opossum (Didelphis marsupialis) from the city of São Paulo, Brazil.

    PubMed

    Yai, L E O; Cañon-Franco, W A; Geraldi, V C; Summa, M E L; Camargo, M C G O; Dubey, J P; Gennari, S M

    2003-08-01

    Antibodies to Neospora caninum and Toxoplasma gondii were assayed in sera of 396 opossums (Didelphis marsupialis) from the city of São Paulo, Brazil. Antibodies to N. caninum were assayed using the indirect immunofluorescent antibody test (IFAT). Antibodies (IFAT, approximately 1:25) to N. caninum were found in 84 opossums (D. marsupialis) in titers of 1:25 in 46, 1:50 in 20, 1:100 in 17, and 1:400 in 1. Antibodies to T. gondii were assayed with the modified agglutination test (MAT) and the IFAT. Antibodies to T. gondii (MAT, approximately 1:25) were found in 82 (20.4%) of the 396 opossums, in titers of 1:25 in 24, 1:50 in 26, 1:100 in 18, 1:200 in 13, and 1:800 in 1. The IFAT antibodies to T. gondii were found in 148 of 396 opossums, in titers of 1:16 in 41, 1:32 in 23, 1:64 in 13, 1:128 in 6, 1:256 in 20, 1:512 in 17, 1:1,024 in 10, 1:2,048 in 10, 1:4,096 in 7, and 1:8,192 in 1. This is the first report of N. caninum and T. gondii infections in D. marsupialis.

  13. Single agglutinates: A comparative study of compositions of agglutinitic glass, whole-grain, bulk soil, and FMR

    NASA Technical Reports Server (NTRS)

    Basu, A.; Robinson, R.; Mckay, D. S.; Blanchard, D. P.; Morris, R. V.; Wentworth, Susan J.

    1994-01-01

    Previous workers on single agglutinates have variously interpreted the composition of agglutinitic glass to represent impact melts of (1) bulk soil, (2) mixed components in finer sizes, and (3) microtargets. Separately, Papike has argued in favor of fusion of the finest fraction of bulk soils. Thirty-four single agglutinates were hand-picked from the mature Apollo 16 soil 61181 (I(sub s)/FeO = 82) and the FMR and chemical composition (INAA for Fe, Sc, Sm, Co, Ni, and Cr) of each agglutinate particle were measured. Thirteen of these single agglutinates were selected for electron beam microanalysis and imaging. Less than 1 micron spots were analyzed (for Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Mn, Fe, Ni, and Ba) on pure glassy areas (approximately ten in each particle) selected on the basis of optical and BSE images (avoiding all clasts and inclusions) with an electron microprobe to obtain average glass compositions of each single agglutinate.

  14. Process to create simulated lunar agglutinate particles

    NASA Technical Reports Server (NTRS)

    Gustafson, Robert J. (Inventor); Gustafson, Marty A. (Inventor); White, Brant C. (Inventor)

    2011-01-01

    A method of creating simulated agglutinate particles by applying a heat source sufficient to partially melt a raw material is provided. The raw material is preferably any lunar soil simulant, crushed mineral, mixture of crushed minerals, or similar material, and the heat source creates localized heating of the raw material.

  15. Experimental shock metamorphism of terrestrial basalts: Agglutinate-like particle formation, petrology, and magnetism

    NASA Astrophysics Data System (ADS)

    Badyukov, Dmitrii D.; Bezaeva, Natalia S.; Rochette, Pierre; Gattacceca, Jérôme; Feinberg, Joshua M.; Kars, Myriam; Egli, Ramon; Raitala, Jouko; Kuzina, Dilyara M.

    2018-01-01

    Hypervelocity impacts occur on bodies throughout our solar system, and play an important role in altering the mineralogy, texture, and magnetic properties in target rocks at nanometer to planetary scales. Here we present the results of hypervelocity impact experiments conducted using a two-stage light-gas gun with 5 mm spherical copper projectiles accelerated toward basalt targets with 6 km s-1 impact velocities. Four different types of magnetite- and titanomagnetite-bearing basalts were used as targets for seven independent experiments. These laboratory impacts resulted in the formation of agglutinate-like particles similar in texture to lunar agglutinates, which are an important fraction of lunar soil. Materials recovered from the impacts were examined using a suite of complementary techniques, including optical and scanning electron microscopy, micro-Raman spectroscopy, and high- and low-temperature magnetometry, to investigate the texture, chemistry, and magnetic properties of newly formed agglutinate-like particles and were compared to unshocked basaltic parent materials. The use of Cu-projectiles, rather than Fe- and Ni-projectiles, avoids magnetic contamination in the final shock products and enables a clearer view of the magnetic properties of impact-generated agglutinates. Agglutinate-like particles show shock features, such as melting and planar deformation features, and demonstrate shock-induced magnetic hardening (two- to seven-fold increases in the coercivity of remanence Bcr compared to the initial target materials) and decreases in low-field magnetic susceptibility and saturation magnetization.

  16. Seroprevalence of leptospiral antibodies among market workers and food handlers in the central state of Malaysia.

    PubMed

    Samsudin, S; Sakinah, S N S; Malina, O; Norliza, B A; Noh, M A; Fairuz, A; Jamaluddin, T Z M T; Hamat, R A; Zahiruddin, W M; Mohd Nazri, S; Sukeri, S; Aziah, B D; Zawaha, I; Zainudin, A W; Munirah, N A; Desa, M N; Neela, V; Masri, S N

    2018-03-01

    The high prevalence of leptospirosis in humans is of great public health concern, particularly in tropical and subtropical regions. This study aimed to determine the seroprevalence of leptospiral antibodies and distribution of serovars, and to assess the usefulness of enzyme-linked immunosorbent assay (ELISA) as a screening method for leptospiral antibodies in a high-risk healthy community. Cross-sectional study of 231 market workers and food handlers in wet markets and food premises from two localities in central Malaysia. Respondents' background information was obtained using a questionnaire. Serum samples were tested for leptospiral antibodies using ELISA and microscopic agglutination test (MAT). Seroprevalence of leptospirosis among healthy workers was 46.3%. Detection of seropositivity was higher by MAT (46%) than ELISA (15%). We observed high seropositivity among local workers (49%), food handlers (49.5%), females (60.8%) and those aged 34 years and older (46.3%). Local strain LEP175 was the predominant serovar, followed by WHO strain Patoc. Overall seroprevalence among healthy food handlers and market workers was high in this study. The workplace places susceptible individuals at risk of leptospirosis. © 2018 John Wiley & Sons Ltd.

  17. The bovine immune response to Brucella abortus. II. Elimination of some sporadic serological reactions by chelation of divalent cations.

    PubMed Central

    Nielsen, K; Samagh, B S; Speckmann, G; Stemshorn, B

    1979-01-01

    The standard agglutination tests for detecting antibody to Brucella abortus were modified by addition of chelating agents (EDTA and EGTA) to the antigens. Approximately 80% of "singleton" agglutination test reactions, negative on the diagnostic complement fixation test, obtained with cattle sera were eliminated while no decrease in titer was apparent when sera from B. abortus infected or vaccinated cattle were tested. PMID:121242

  18. Seroprevalence of Toxoplasma gondii antibodies in humans from rural Western Amazon, Brazil.

    PubMed

    Cavalcante, G T; Aguilar, D M; Camargo, L M A; Labruna, M B; de Andrade, H F; Meireles, L R; Dubey, J P; Thulliez, P; Dias, R A; Gennari, S M

    2006-06-01

    Antibodies to Toxoplasma gondii were assayed in sera of 266 humans from 71 farms located at Rondônia State, Western Amazon, Brazil, by the modified agglutination test (MAT) and the indirect immunofluorescent antibody test (IFAT). Antibodies were found in 195 humans (73.3%), with MAT titers of 1:25 in 11, 1:50 in 11, 1:100 in 16, 1:200 in 27, 1:400 in 38, 1:800 in 37, 1:1,600 in 22, and 1:3,200 or higher in 33. From the 71 farms visited, 69 had seropositive humans. Prevalence of anti-T. gondii antibodies increased with age of the people (P < 0.05), and no difference was observed in the occurrence by gender (P > 0.05). A sanitary questionnaire was applied in each farm, and statistical association between the serologic status and several variables were analyzed. Home-grown vegetable consumption and origin of drinking water (well or river) were the independent variables that displayed significant association (P = 0.002 and 0.02, respectively). Higher values of occurrence were found in people with consumption of home-grown vegetables (76.1%) and people that drink well water (75.4%) compared with people that did not consume this type of food (61.9%) and drink river water (55.2%). By IFAT (> or = 1:16), 194 of 266 (73%) humans were seropositive and there was a good correlation between MAT and IFAT.

  19. Studies on a Factor in Sweet Potato Root Which Agglutinates Spores of Ceratocystis fimbriata, Black Rot Fungus 1

    PubMed Central

    Kojime, Mineo; Kawakita, Kazuhito; Uritani, Ikuzo

    1982-01-01

    A factor which agglutinated the spores of Ceratocystis fimbriata in the presence of Ca2+ was purified from sweet potato (Ipomea batatas Lam cv. Norin[1]) root. Element composition of the purified factor was as follows; analysis found: C (29.8%), H (3.97%), O (65.34%), N (0.81%): calculated for C43H69O70N1: C (30.02%), H (4.01%), O (65.15%), N (0.81%). The factor was mainly composed of galacturonic acid (53% of dry weight) and contained arabinose, fucose, and unidentified component as minor components. The factor also agglutinated A-, B-, AB-, and O types of human erythrocytes to almost the same degree in the presence of Ca2+. The differential spore-agglutinating activity of the factor depended on the pH of the assay medium; it agglutinated similarly the germinated spores of sweet potato and coffee strains at pH 7.5 and 5.5, whereas it displayed a distinct differential agglutinating activity at pH 6.5. The factor was assayed for spore-agglutinating activity at pH 6.5, using the germinated and ungerminated spores of seven strains of C. fimbriata; sweet potato, coffee, prune, cacao, oak, taro, and almond strains. The factor agglutinated ungerminated spores of all seven strains similarly, although small differences were observed among strains. On the other hand, a clear differential agglutination was observed among the germinated spores of various strains; sweet potato and almond strains were highly insensitive in comparison with other strains. The growth of the agglutinated spores of C. fimbriata was inhibited. These results are discussed in relation to host-parasite specificity. Images PMID:16662232

  20. Seroprevalence of Toxoplasma gondii antibodies in cats and pigs from rural Western Amazon, Brazil.

    PubMed

    Cavalcante, G T; Aguiar, D M; Chiebao, D; Dubey, J P; Ruiz, V L A; Dias, R A; Camargo, L M A; Labruna, M B; Gennari, S M

    2006-08-01

    Antibodies to Toxoplasma gondii were assayed in sera of 63 cats and 80 pigs from 71 farms located at Rondônia State, Western Amazon, Brazil, by the modified agglutination test (MAT) and the indirect immunofluorescent antibody test (IFAT). Antibodies (MAT > or = 1: 25) were found in 55 of 63 cats (87.3%) with titers of 1:25 in 2, 1:50 in 2, 1:100 in 7, 1:200 in 1, 1:400 in 2, 1:800 in 9, 1:1,600 in 6, and 1:3,200 or higher in 26 cats. By IFAT, antibodies were found in 55 cats (87.3%) with titers of 1:25 in 2, 1:50 in 1, 1:100 in 4, 1:200 in 4, 1: 400 in 1, 1:800 in 13, 1:1,600 in 12, and 1:3,200 or higher in 18 cats. In pig sera, by MAT, antibodies were found in 30 of 80 pigs (37.5%) with titers of 1:25 in 2, 1:50 in 3, 1:100 in 2, 1:200 in 8, 1:400 in 3, 1:800 in 5, 1:1,600 in 3, and 1:3,200 or higher in 4 pigs. By using the IFAT (titers > or = 1:64), antibodies were found in 35 (43.7%) pigs. The ingestion of undercooked tissues of infected pigs can be a source of T. gondii infection for humans and cats. However, the high seroprevalence of T. gondii in cats from the Amazon seems most likely to be indicative of high contamination of the environment by oocysts.

  1. Detection of Leptospira spp. and Brucella abortus antibodies in free-living jaguars (Panthera onca) in two protected areas of northern Pantanal, Brazil.

    PubMed

    Onuma, Selma Samiko Miyazaki; Kantek, Daniel Luis Zanella; Crawshaw Júnior, Peter Gransden; Morato, Ronaldo Gonçalves; May-Júnior, Joares Adenilson; Morais, Zenaide Maria de; Ferreira Neto, José Soares; Aguiar, Daniel Moura de

    2015-01-01

    This study aimed to assess the exposure of free-living jaguars (Panthera onca) to Leptospira spp. and Brucella abortus in two conservation units in the Pantanal of Mato Grosso, Brazil. The presence of antibodies in blood samples of eleven jaguars was investigated using autochthonous antigens isolated in Brazil added to reference antigen collection applied to diagnosis of leptospirosis by Microscopic Agglutination Test (MAT). The Rose Bengal test was applied for B. abortus antibodies. Two (18.2%) jaguars were seroreactive for the Leptospira spp. antigen and the serovar considered as most infective in both animals was a Brazilian isolate of serovar Canicola (L01). All jaguars were seronegative for B. abortus. These data indicate that the inclusion of autochthonous antigens in serological studies can significantly increase the number of reactive animals, as well as modify the epidemiological profile of Leptospira spp. infection.

  2. DARPA Antibody Technology Program. Standardized Test Bed for Antibody Characterization: Characterization of an MS2 ScFv Antibody Produced by Illumina

    DTIC Science & Technology

    2016-08-01

    platforms. 15. SUBJECT TERMS Antibody Antibody Technology Program (ATP) Quality Enzyme-linked immunosorbent assay ( ELISA ) Biosurveillance Single-chain...2.6 Thermal Stress Test............................................................................................4 2.7 ELISA ...3.5 ELISA Results .................................................................................................11 3.6 SPR Results

  3. Dodecamer is required for agglutination of Litopenaeus vannamei hemocyanin with bacterial cells and red blood cells.

    PubMed

    Pan, Jian-yi; Zhang, Yue-ling; Wang, San-ying; Peng, Xuan-xian

    2008-01-01

    Hemocyanins are multi-functional proteins, although they are well known to be respiratory proteins of invertebrate to date. In the present study, the agglutination ability of two oligomers of hemocyanin, hexamer and dodecamer, with pathogenic bacteria and red blood cells (RBCs) is investigated in pacific white shrimp, Litopenaeus vannamei. Hexameric hemocyanin exhibits an extremely high stability even in the absence of Ca(2+) and in alkaline pH. Dodecamer (di-hexamer) is easily dissociated into hexamers in unphysiological conditions. Hexamer and dodecamer are interchanged reciprocally with environmental conditions. Both oligomers can bind to bacteria and RBCs, but agglutination is observed only using dodecamer but not using hexamer in agglutination assay. However, the agglutination is detected when hexamer is utilized in the presence of antiserum against hemocyanin. These results indicate that dodecamer of hemocyanin is required for agglutination with bacteria and RBCs. It can be logically inferred that there is only one carbohydrate-binding site to bacterial cells and RBCs in the hexamer, while at least two sites in the dodecamer. Our finding has provided new insights into structural-functional relationship of hemocyanin.

  4. Effect of salivary agglutination on oral streptococcal clearance by human polymorphonuclear neutrophil granulocytes

    PubMed Central

    Itzek, Andreas; Chen, Zhiyun; Merritt, Justin; Kreth, Jens

    2016-01-01

    Salivary agglutination is an important host defense mechanism to aggregate oral commensal bacteria as well as invading pathogens. Saliva flow and subsequent swallowing more easily clear aggregated bacteria compared to single cells. Phagocytic clearance of bacteria through polymorphonuclear neutrophil granulocytes also seems to increase to a certain extent with the size of bacterial aggregates. To determine a connection between salivary agglutination and the host innate immune response by phagocytosis, an in vitro agglutination assay was developed reproducing the average size of salivary bacterial aggregates. Using the oral commensal Streptococcus gordonii as a model organism, the effect of salivary agglutination to the phagocytic clearance through polymorphonuclear neutrophil granulocytes was investigated. Here we describe that salivary aggregates of S. gordonii are readily cleared through phagocytosis, while single bacterial cells showed a significant delay in being phagocytosed and killed. Furthermore, prior to phagocytosis the polymorphonuclear neutrophil granulocytes were able to induce a specific de-aggregation, which was dependent on serine protease activity. The herein presented data suggest that salivary agglutination of bacterial cells leads to an ideal size for recognition by polymorphonuclear neutrophil granulocytes. As a first line of defense, these phagocytic cells are able to recognize the aggregates and de-aggregate them via serine proteases to a more manageable size for efficient phagocytosis and subsequent killing in the phagolysosome. This observed mechanism not only prevents the rapid spreading of oral bacterial cells while entering the bloodstream but would also avoid degranulation of involved polymorphonuclear neutrophil granulocytes thus preventing collateral damage to nearby tissue. PMID:27194631

  5. Effect of salivary agglutination on oral streptococcal clearance by human polymorphonuclear neutrophil granulocytes.

    PubMed

    Itzek, A; Chen, Z; Merritt, J; Kreth, J

    2017-06-01

    Salivary agglutination is an important host defense mechanism to aggregate oral commensal bacteria as well as invading pathogens. Saliva flow and subsequent swallowing more easily clear aggregated bacteria compared with single cells. Phagocytic clearance of bacteria through polymorphonuclear neutrophil granulocytes also seems to increase to a certain extent with the size of bacterial aggregates. To determine a connection between salivary agglutination and the host innate immune response by phagocytosis, an in vitro agglutination assay was developed reproducing the average size of salivary bacterial aggregates. Using the oral commensal Streptococcus gordonii as a model organism, the effect of salivary agglutination on phagocytic clearance through polymorphonuclear neutrophil granulocytes was investigated. Here we describe how salivary aggregates of S. gordonii are readily cleared through phagocytosis, whereas single bacterial cells showed a significant delay in being phagocytosed and killed. Furthermore, before phagocytosis the polymorphonuclear neutrophil granulocytes were able to induce a specific de-aggregation, which was dependent on serine protease activity. The data presented suggest that salivary agglutination of bacterial cells leads to an ideal size for recognition by polymorphonuclear neutrophil granulocytes. As a first line of defense, these phagocytic cells are able to recognize the aggregates and de-aggregate them via serine proteases to a more manageable size for efficient phagocytosis and subsequent killing in the phagolysosome. This observed mechanism not only prevents the rapid spreading of oral bacterial cells while entering the bloodstream but would also avoid degranulation of involved polymorphonuclear neutrophil granulocytes, so preventing collateral damage to nearby tissue. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Study of blood group B antigen with a specific monoclonal antibody (anti-B, b-183).

    PubMed Central

    Rouger, P; Edelman, L; Doinel, C; Reviron, J; Salmon, C; Bach, J F

    1983-01-01

    A murine anti-B monoclonal antibody was obtained by the hybridoma technique. This antibody called anti-B (b-183) is of IgM nature; it is capable of agglutinating normal B, B3, Bx, cis AB and some acquired B red cells. Its association constant is 1.1 X 10(8) l/mol, and appears high compared to those of the monoclonal anti-A. This monoclonal anti-B was used to determine the number of B sites on B3 and Bx red cells. PMID:6840810

  7. Prevalence of antibodies to Leptospira in wild mammals trapped on livestock farms in Ontario, Canada.

    PubMed

    Allen, Samantha E; Ojkic, Davor; Jardine, Claire M

    2014-07-01

    To determine the prevalence and diversity of Leptospira serogroups circulating in wildlife on farms in Ontario, we tested samples from 51 raccoons (Procyon lotor), seven skunks (Mephitis mephitis), four rats (Rattus norvegicus), and three opossums (Didelphis virginiana) that were trapped on 27 livestock (swine [Sus scrofa], cattle [Bos taurus]) farms in 2010. Seventeen of 51 raccoons (33%; 95% confidence interval [CI], 21-48%) sampled were positive for at least one Leptospira serogroup using the microscopic agglutination test. None of the other 14 animals had detectable Leptospira antibodies. On swine farms, 13 of 30 raccoons (43%; 95% CI, 27-61%) were antibody positive, and on cattle farms, four of 21 raccoons (19%; 95% CI, 8-40%) were positive. Leptospira antibody prevalence in raccoons did not differ between swine and cattle farms. Raccoons were positive to serovars representative of serogroups Grippotyphosa, Australis, Icterohaemorrhagiae, and Pomona and were negative to serovars of serogroups Autumnalis, Canicola, and Sejroe. The prevalence of Leptospira antibodies in raccoons in this study is similar to what has been reported previously; however, the diversity of serogroups was higher in this study than what has been reported in raccoons from an urban area of Ontario, Canada. Understanding the prevalence and distribution of Leptospira serogroups in wildlife in Ontario, Canada, is important for the development and maintenance of appropriate disease management strategies in humans, livestock, and companion animals.

  8. Erythrocyte agglutination by wheat germ agglutinin: ionic strength dependence of the contact seam topology.

    PubMed

    Rolfe, M; Parmar, A; Hoy, T G; Coakley, W T

    2001-01-01

    The topology of the cell-cell contact seam formed when normal or pronase pre-treated (PPT) erythrocytes are exposed to wheat germ agglutinin (WGA) in isotonic media of different ionic strengths was examined here. Lectin uptake and cell agglutination were also quantified. Agglutination of normal cells was gradually and significantly inhibited as ionic strength (IS) was reduced from 0.15 (buffered 145 mm NaCl) to 0.105. Agglutination was less inhibited in PPT cells, even when IS was reduced to 0.09. Cell contact seams formed during agglutination showed patterns of localized contacts. The scale of the patterns, i.e. the average lateral separation distance of contact regions, was 0.62 microm for normal cells and was significantly shorter, at 0.44 microm, for PPT cells at an IS of 0.15. The scale increased significantly for both cell types when the IS was reduced to 0.09. Flow cytometry measurements showed that WGA uptake by normal cells increased slightly, whilst that for PPT cells was unchanged, as IS was decreased from 0.15 to 0.09. The results imply that, whilst ionic strength change does not exert a strong influence on intermolecular WGA-ligand binding, physico-chemical modification of the interaction between cells modulates not only the extent and progression of the biospecific lectin-induced cell-cell agglutination but also the topology of the contact seam. The IS dependence of contact separation in WGA-agglutinated cells is contrasted here with that reported for cells adhering in dextran solutions. The influence of IS change and pronase pre-treatment on contact pattern are consistent with predictions, from interfacial instability theory, of punctuate thinning of the aqueous layer separating bilayer membranes in close apposition.

  9. Outbreak of uncommon O4 non-agglutinating Salmonella typhimurium linked to minced pork, Saxony-Anhalt, Germany, January to April 2013.

    PubMed

    Alt, Katja; Simon, Sandra; Helmeke, Carina; Kohlstock, Claudia; Prager, Rita; Tietze, Erhard; Rabsch, Wolfgang; Karagiannis, Ioannis; Werber, Dirk; Frank, Christina; Fruth, Angelika

    2015-01-01

    In January 2013, the National Reference Centre for Salmonella (NRC) detected a salmonellosis cluster in Saxony-Anhalt, Germany, caused by uncommon O4 non-agglutinating, monophasic Salmonella (S.) Typhimurium DT193. Circulating predominant monophasic S. Typhimurium DT193 clones typically display resistance phenotype ASSuT. We investigated common exposures to control the outbreak, and conducted microbiological investigations to assess the strains' phenotype. We conducted a case-control study defining cases as persons living or working in Saxony-Anhalt diagnosed with the O4 non-agglutinating strain between January and March 2013. We selected two controls contemporarily reported with norovirus infection, frequency-matched on residence and age group, per case. We interviewed regarding food consumption, especially pork and its place of purchase. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI) using logistic regression. The NRC investigated human and food isolates by PCR, SDS-PAGE, MLST, PFGE, MLVA and susceptibility testing. Altogether, 68 O4 non-agglutinating human isolates were confirmed between January and April 2013. Of those, 61 were assigned to the outbreak (median age 57 years, 44% female); 83% cases ≥ 60 years were hospitalized. Eating raw minced pork from butcheries within 3 days was associated with disease (31 cases, 28 controls; OR adjusted for sex: 3.6; 95% CI: 1.0-13). Phage type DT193 and MLST ST34 were assigned, and isolates' lipopolysaccharide (LPS) matched control strains. Isolates linked to Saxony-Anhalt exhibited PFGE type 5. ASSuT- and ACSSuT phenotype proportions were 34 and 39% respectively; 54% were resistant to chloramphenicol. Three pork isolates matched the outbreak strain. Raw minced pork was the most likely infection vehicle in this first reported outbreak caused by O4 non-agglutinating, mostly chloramphenicol-resistant S. Typhimurium DT193. High hospitalization proportions demand awareness on the risk of consumption

  10. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Systems § 866.5120 Antismooth muscle antibody immunological test system. (a) Identification. An antismooth muscle antibody immunological test system is a device that consists of the reagents used to measure by... serum. The measurements aid in the diagnosis of chronic hepatitis (inflammation of the liver) and...

  11. 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

  12. ANCA / MPO / PR3 Antibodies Test

    MedlinePlus

    ... normal limits." For more information, please read the article Reference Ranges and What They Mean . What is being tested? Antineutrophil cytoplasmic antibodies (ANCA) are autoantibodies produced by a person's immune system that mistakenly target and attack proteins within the ...

  13. [Methicillin resistance detection in Staphylococcus aureus: comparison between conventional methods and MRSA-Screen latex agglutination technique].

    PubMed

    Soloaga, R; Corso, A; Gagetti, P; Faccone, D; Galas, M

    2004-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the "gold standard" for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100%, agar dilution 97 and 95%, oxacillin agar screen test 100 and 100%, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.

  14. 21 CFR 866.5090 - Antimitochondrial antibody immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... immunochemical techniques the antimitochondrial antibodies in human serum. The measurements aid in the diagnosis of diseases that produce a spectrum of autoantibodies (antibodies produced against the body's own... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test...

  15. 21 CFR 866.5090 - Antimitochondrial antibody immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... immunochemical techniques the antimitochondrial antibodies in human serum. The measurements aid in the diagnosis of diseases that produce a spectrum of autoantibodies (antibodies produced against the body's own... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test...

  16. 21 CFR 866.5090 - Antimitochondrial antibody immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... immunochemical techniques the antimitochondrial antibodies in human serum. The measurements aid in the diagnosis of diseases that produce a spectrum of autoantibodies (antibodies produced against the body's own... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test...

  17. Analysis of HTLV-1 proviral load (PVL) and antibody detected with various kinds of tests in Japanese blood donors to understand the relationship between PVL and antibody level and to gain insights toward better antibody testing.

    PubMed

    Matsumoto, Chieko; Sagara, Yasuko; Sobata, Rieko; Inoue, Yukiko; Morita, Maiko; Uchida, Shigeharu; Kiyokawa, Hiroyuki; Satake, Masahiro; Tadokoro, Kenji

    2017-08-01

    Adult T-cell leukemia/lymphoma (ATL) occurs in approximately 5% of individuals infected with human T-cell leukemia virus type 1 (HTLV-1). A high proviral load (PVL; more than four copies per 100 peripheral blood mononuclear cells (PBMCs) or 1.6 copies per 100 blood leukocytes) and being male are risk factors for ATL development. Whether anti-HTLV-1 antibody level is related to such risk is unknown. Here, PVL and antibody levels were examined using real-time PCR and other tests in 600 HTLV-1 positive screened Japanese blood donors to understand the relationship between PVL and antibody level in asymptomatic carriers and to gain insights toward better antibody testing for HTLV-1 infection. The 430 donors in whom proviral DNA was detected were considered as true positives for HTLV-1 infection. Among donors aged 40 years or older, more males than females had a PVL corresponding to more than 1.6% infected leukocytes, and an antibody titer below the median (P = 0.0018). In antibody tests using an HTLV-1 positive cell line or Env antigens there was a large discrepancy in antibody titer among 13 provirus-positive samples, probably suggesting that antibody-based screening tests should incorporate multiple HTLV-1 antigens, such as Gag and Env antigens. © 2017 Wiley Periodicals, Inc.

  18. Genetic and mechanistic evaluation for the mixed-field agglutination in B3 blood type with IVS3+5G>A ABO gene mutation.

    PubMed

    Chen, Ding-Ping; Tseng, Ching-Ping; Wang, Wei-Ting; Sun, Chien-Feng

    2012-01-01

    The ABO blood type B(3) is the most common B subtype in the Chinese population with a frequency of 1/900. Although IVS3+5G>A (rs55852701) mutation of B gene has been shown to associate with the development of B(3) blood type, genetic and mechanistic evaluation for the unique mixed-field agglutination phenotype has not yet been completely addressed. In this study, we analyzed 16 cases of confirmed B(3) individuals and found that IVS3+5G>A attributes to all cases of B(3). RT-PCR analyses revealed the presence of at least 7 types of aberrant B(3) splicing transcripts with most of the transcripts causing early termination and producing non-functional protein during translation. The splicing transcript without exon 3 that was predicted to generate functional B(3) glycosyltransferase lacking 19 amino acids at the N-terminal segment constituted only 0.9% of the splicing transcripts. Expression of the B(3) cDNA with exon 3 deletion in the K562 erythroleukemia cells revealed that the B(3) glycosyltransferase had only 40% of B(1) activity in converting H antigen to B antigen. Notably, the typical mixed-field agglutination of B(3)-RBCs can be mimicked by adding anti-B antibody to the K562-B(3) cells. This study thereby demonstrates that both aberrant splicing of B transcripts and the reduced B(3) glycosyltransferase activity contribute to weak B expression and the mixed-field agglutination of B(3), adding to the complexity for the regulatory mechanisms of ABO gene expression.

  19. Comparison of a New and Rapid Method: Brucella Coombs Gel Test With Other Diagnostic Tests.

    PubMed

    Kalem, Fatma; Ergün, Ayşe Gül; Durmaz, Süleyman; Doğan, Metin; Ertuğrul, Ömür; Gündem, Seval

    2016-09-01

    The aim of this study was to detect reliability of Brucella Coombs gel test (BCGT) by comparing with with ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination methods in serological diagnosis of brucellosis. Brucella Coombs gel test (BCGT), Brucella ELISA (IgG + IgM), Standard agglutination test, and Brucella immunocapture agglutination tests of 78 patients with presumptive diagnosis of brucellosis which were sent to Microbiology Laboratory of Konya Numune Hospital from various regions of Konya were studied. Of 78 patients with ELISA IgG and IgM, STA, BICA and BCGT; 26, 21, 10, 12 and 12 were positive. When compared with BICA, the sensitivity and specifity of BCGT were 100% and 100%, respectively. According to results BCGT can be used as a diagnostic test in routine laboratories after more comprehensive studies in control groups and patients. © 2016 Wiley Periodicals, Inc.

  20. Th2-biased immune response and agglutinating antibodies generation by a chimeric protein comprising OmpC epitope (323-336) of Aeromonas hydrophila and LTB.

    PubMed

    Sharma, Mahima; Dash, Pujarini; Sahoo, Pramod K; Dixit, Aparna

    2018-02-01

    Aeromonas hydrophila is responsible for causing fatal infections in freshwater fishes. Besides chemical/antibiotic treatment and whole-cell vaccine, no subunit vaccine is currently available for A. hydrophila. Outer membrane proteins of gram-negative bacteria have been reported as effective vaccine candidates. Peptide antigens elicit focused immune responses against immunodominant stretches of the antigen. We have attempted to characterize the immunogenicity of linear B-cell epitopes of outer membrane protein (OmpC) of A. hydrophila identified using in silico tools, in conjugation with heat-labile enterotoxin B (LTB) subunit of Escherichia coli as a carrier protein. Antisera against the fusion protein harboring 323-336 residues of the AhOmpC (raised in mice) showed maximum cross-reactivity with the parent protein OmpC and LTB. The fusion protein displayed efficient GM 1 ganglioside receptor binding, retaining the adjuvanicity of LTB. Antibody isotype profile and in vitro T-cell response analysis, cytokine ELISA, and array analysis collectively revealed a Th2-biased mixed T-helper cell response. Agglutination assay and flow cytometry analysis validated the ability of anti-fusion protein antisera to recognize the surface exposed epitopes on Aeromonas cells, demonstrating its neutralization potential. Oral immunization studies in Labeo rohita resulted in the generation of long-lasting humoral immune response, and the antisera could cross-react with the fusion protein as well as both the fusion partners. Considering significant similarity among OmpC of different enteric bacteria, the use of A. hydrophila OmpC epitope 323-336 in fusion with LTB could have a broader scope in vaccine design.

  1. 21 CFR 660.54 - Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. 660.54 Section 660.54 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR...

  2. 21 CFR 660.54 - Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. 660.54 Section 660.54 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR...

  3. 21 CFR 660.54 - Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. 660.54 Section 660.54 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR...

  4. 21 CFR 660.54 - Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Potency tests, specificity tests, tests for heterospecific antibodies, and additional tests for nonspecific properties. 660.54 Section 660.54 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR...

  5. DETECTION OF Leptospira spp. AND Brucella abortus ANTIBODIES IN FREE-LIVING JAGUARS (Panthera onca) IN TWO PROTECTED AREAS OF NORTHERN PANTANAL, BRAZIL

    PubMed Central

    ONUMA, Selma Samiko Miyazaki; KANTEK, Daniel Luis Zanella; CRAWSHAW, Peter Gransden; MORATO, Ronaldo Gonçalves; MAY-JÚNIOR, Joares Adenilson; de MORAIS, Zenaide Maria; FERREIRA, José Soares; de AGUIAR, Daniel Moura

    2015-01-01

     This study aimed to assess the exposure of free-living jaguars (Panthera onca) to Leptospira spp. and Brucella abortus in two conservation units in the Pantanal of Mato Grosso, Brazil. The presence of antibodies in blood samples of eleven jaguars was investigated using autochthonous antigens isolated in Brazil added to reference antigen collection applied to diagnosis of leptospirosis by Microscopic Agglutination Test (MAT). The Rose Bengal test was applied for B. abortus antibodies. Two (18.2%) jaguars were seroreactive for the Leptospira spp. antigen and the serovar considered as most infective in both animals was a Brazilian isolate of serovar Canicola (L01). All jaguars were seronegative for B. abortus. These data indicate that the inclusion of autochthonous antigens in serological studies can significantly increase the number of reactive animals, as well as modify the epidemiological profile of Leptospira spp. infection. PMID:25923900

  6. 'Agglutination and flocculation' of stem cells collected by apheresis due to cryofibrinogen.

    PubMed

    Siegenthaler, M A; Vu, D-H; Ebnöther, M; Ketterer, N; Luthi, F; Schmid, P; Bargetzi, M; Gasparini, D; Tissot, J-D

    2004-04-01

    Collection of peripheral stem cells by apheresis is a well-described process. Here, investigations concerning 'agglutination and flocculation' of stem cells collected from two patients are described. In both cases, cryoproteins were observed and cryofibrinogen was identified using high-resolution two-dimensional electrophoresis. In one case, peripheral stem cells were collected after a second course of mobilization, and the cells were immediately washed at 37 degrees C before being frozen, allowing their use, despite the presence of cryofibrinogen. In the other case, 'agglutination' was reversed by warming the bag, and plasma was removed before freezing.

  7. Seroprevalence of Toxoplasma gondii infection in captive mammals in three zoos in Mexico City, Mexico

    USDA-ARS?s Scientific Manuscript database

    Antibodies to Toxoplasma gondii were determined in 167 mammals in 3 zoos in Mexico City, Mexico using the modified agglutination test (MAT). Overall, antibodies to T. gondii were found in 89 (53.3%) of the 167 animals tested. Antibodies were found in 35 of 43 wild Felidae: 2 of 2 bobcats (Lynx rufus...

  8. Real time observation and automated measurement of red blood cells agglutination inside a passive microfluidic biochip containing embedded reagents.

    PubMed

    Huet, Maxime; Cubizolles, Myriam; Buhot, Arnaud

    2017-07-15

    The process of agglutination is commonly used for the detection of biomarkers like proteins or viruses. The multiple bindings between micrometer sized particles, either latex beads or red blood cells (RBCs), create aggregates that are easily detectable and give qualitative information about the presence of the biomarkers. In most cases, the detection is made by simple naked-eye observation of agglutinates without any access to the kinetics of agglutination. In this study, we address the development of a real-time time observation of RBCs agglutination. Using ABO blood typing as a proof-of-concept, we developed i) an integrated biological protocol suitable for further use as point-of-care (POC) analysis and ii) two dedicated image processing algorithms for the real-time and quantitative measurement of agglutination. Anti-A or anti-B typing reagents were dried inside the microchannel of a passive microfluidic chip designed to enhance capillary flow. A blood drop deposit at the tip of the biochip established a simple biological protocol. In situ agglutination of autologous RBCs was achieved by means of embedded reagents and real time agglutination process was monitored by video recording. Using a training set of 24 experiments, two real-time indicators based on correlation and variance of gray levels were optimized and then further confirmed on a validation set. 100% correct discrimination between positive and negative agglutinations was performed within less than 2min by measuring real-time evolution of both correlation and variance indicators. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. A deep-sea agglutinated foraminifer tube constructed with planktonic foraminifer shells of a single species

    NASA Astrophysics Data System (ADS)

    Pearson, Paul N.; Expedition 363 Shipboard Scientific Party, IODP

    2018-01-01

    Agglutinated foraminifera are marine protists that show apparently complex behaviour in constructing their shells, involving selecting suitable sedimentary grains from their environment, manipulating them in three dimensions, and cementing them precisely into position. Here we illustrate a striking and previously undescribed example of complex organisation in fragments of a tube-like foraminifer (questionably assigned to Rhabdammina) from 1466 m water depth on the northwest Australian margin. The tube is constructed from well-cemented siliciclastic grains which form a matrix into which hundreds of planktonic foraminifer shells are regularly spaced in apparently helical bands. These shells are of a single species, Turborotalita clarkei, which has been selected to the exclusion of all other bioclasts. The majority of shells are set horizontally in the matrix with the umbilical side upward. This mode of construction, as is the case with other agglutinated tests, seems to require either an extraordinarily selective trial-and-error process at the site of cementation or an active sensory and decision-making system within the cell.

  10. The Production of Nominal and Verbal Inflection in an Agglutinative Language: Evidence from Hungarian

    PubMed Central

    Peckham, Don; Szanka, Szilvia; Gazso, Dorottya; Lovassy, Noemi; Ullman, Michael T.

    2015-01-01

    The contrast between regular and irregular inflectional morphology has been useful in investigating the functional and neural architecture of language. However, most studies have examined the regular/irregular distinction in non-agglutinative Indo-European languages (primarily English) with relatively simple morphology. Additionally, the majority of research has focused on verbal rather than nominal inflectional morphology. The present study attempts to address these gaps by introducing both plural and past tense production tasks in Hungarian, an agglutinative non-Indo-European language with complex morphology. Here we report results on these tasks from healthy Hungarian native-speaking adults, in whom we examine regular and irregular nominal and verbal inflection in a within-subjects design. Regular and irregular nouns and verbs were stem on frequency, word length, and phonological structure, and both accuracy and response times were acquired. The results revealed that the regular/irregular contrast yields similar patterns in Hungarian, for both nominal and verbal inflection, as in previous studies of non-agglutinative Indo-European languages: the production of irregular inflected forms was both less accurate and slower than of regular forms, both for plural and past-tense inflection. The results replicate and extend previous findings to an agglutinative language with complex morphology. Together with previous studies, the evidence suggests that the regular/irregular distinction yields a basic behavioral pattern that holds across language families and linguistic typologies. Finally, the study sets the stage for further research examining the neurocognitive substrates of regular and irregular morphology in an agglutinative non-Indo-European language. PMID:25769039

  11. Serodiagnosis of infectious mononucleosis with a bovine erythrocyte glycoprotein.

    PubMed

    Fletcher, M A; Klimas, N G; Latif, Z A; Caldwell, K E

    1983-09-01

    A glycoprotein from bovine erythrocyte membrane was evaluated in two immunoassays as a reagent for the serodiagnosis of infectious mononucleosis (IM). We previously reported that a partially purified preparation of this glycoprotein, when attached to latex beads, agglutinated in the presence of IM heterophile antibody. In the present study, we used a highly purified form of the glycoprotein both as an agglutinating reagent, covalently bound to latex, and in a solid-phase sandwich-type radioimmunoassay (RIA) for IM antibody detection in a larger population of patients. We tested serum samples from college students with symptoms suggestive of IM with the latex reagent (143 samples) and with the RIA (245 samples). Correlation of these two tests, both with each other and with the classical differentially absorbed, agglutination tests for Paul-Bunnell antibody in IM sera, using fresh sheep or horse cells, was excellent (greater than 97% agreement). The new tests also corresponded in most cases with a rapid, unabsorbed preserved horse erythrocyte slide test. However, in this study of 245 samples, both apparent false-positives (5 samples) and apparent false-negatives (3 samples) were observed with this slide test. In conclusion, we found that the bovine glycoprotein as a reagent can facilitate the diagnosis of IM, giving results comparable to those with erythrocyte agglutination tests on differentially absorbed sera. The advantages are ease and speed of performance (latex test), potential for automation (RIA test), stability and uniformity of the glycoprotein reagent (latex and RIA tests), and most importantly, the ability to use unabsorbed sera (latex and RIA tests).

  12. Diagnosis and treatment of Neospora caninum--associated dermatitis in a red fox (Vulpes vulpes) with concurrent Toxoplasma gondii infection.

    PubMed

    Duhey, Jitender P; Whitesell, Leah E; Culp, William E; Daye, Sharon

    2014-06-01

    A 3-mo-old red fox (Vulpes vulpes) developed generalized crusty plaques on its body during rehabilitation after an automobile accident requiring amputation of one leg. Histologic examination of skin lesion biopsy revealed granulomatous dermatitits with many intralesional protozoal tachyzoites. The protozoa stained positively with antibodies to Neospora caninum but not to Toxoplasma gondii. Treatment with clindamycin hydrochloride (10 mg/kg, twice daily, s.c.) for 1 mo completely resolved lesions, and protozoa were not demonstrable in biopsy of skin after treatment. The fox had agglutinating antibodies to T. gondii (modified agglutination test, titer 1:3200) and N. caninum (Neospora agglutination test, titer 1:25), and viable T. gondii (genotype III) was isolated from the skin biopsy after treatment. This is the first report of clinical neosporosis in a wild canid.

  13. Public health consequences of a false-positive laboratory test result for Brucella--Florida, Georgia, and Michigan, 2005.

    PubMed

    2008-06-06

    Human brucellosis, a nationally notifiable disease, is uncommon in the United States. Most human cases have occurred in returned travelers or immigrants from regions where brucellosis is endemic, or were acquired domestically from eating illegally imported, unpasteurized fresh cheeses. In January 2005, a woman aged 35 years who lived in Nassau County, Florida, received a diagnosis of brucellosis, based on results of a Brucella immunoglobulin M (IgM) enzyme immunoassay (EIA) performed in a commercial laboratory using analyte specific reagents (ASRs); this diagnosis prompted an investigation of dairy products in two other states. Subsequent confirmatory antibody testing by Brucella microagglutination test (BMAT) performed at CDC on the patient's serum was negative. The case did not meet the CDC/Council of State and Territorial Epidemiologists' (CSTE) definition for a probable or confirmed brucellosis case, and the initial EIA result was determined to be a false positive. This report summarizes the case history, laboratory findings, and public health investigations. CDC recommends that Brucella serology testing only be performed using tests cleared or approved by the Food and Drug Administration (FDA) or validated under the Clinical Laboratory Improvement Amendments (CLIA) and shown to reliably detect the presence of Brucella infection. Results from these tests should be considered supportive evidence for recent infection only and interpreted in the context of a clinically compatible illness and exposure history. EIA is not considered a confirmatory Brucella antibody test; positive screening test results should be confirmed by Brucella-specific agglutination (i.e., BMAT or standard tube agglutination test) methods.

  14. A Dual Point-of-Care Test Shows Good Performance in Simultaneously Detecting Nontreponemal and Treponemal Antibodies in Patients With Syphilis: A Multisite Evaluation Study in China

    PubMed Central

    Yin, Yue-Ping; Chen, Xiang-Sheng; Wei, Wan-Hui; Gong, Kuang-Long; Cao, Wen-Ling; Yong, Gang; Feng, Liang; Huang, Shu-Jie; Wang, Dong-Mei; Han, Yan; Chen, Shao-Chun; Mabey, David; Peeling, Rosanna W.

    2013-01-01

    Background. Rapid point-of-care (POC) syphilis tests based on simultaneous detection of treponemal and nontreponemal antibodies (dual POC tests) offer the opportunity to increase coverage of syphilis screening and treatment. This study aimed to conduct a multisite performance evaluation of a dual POC syphilis test in China. Methods. Participants were recruited from patients at sexually transmitted infection clinics and high-risk groups in outreach settings in 6 sites in China. Three kinds of specimens (whole blood [WB], fingerprick blood [FB], and blood plasma [BP]) were used for evaluating sensitivity and specificity of the Dual Path Platform (DPP) Syphilis Screen and Confirm test using its treponemal and nontreponemal lines to compare Treponema pallidum particle agglutination (TPPA) assay and toluidine red unheated serum test (TRUST) as reference standards. Results. A total of 3134 specimens (WB 1323, FB 488, and BP 1323) from 1323 individuals were collected. The sensitivities as compared with TPPA were 96.7% for WB, 96.4% for FB, and 94.6% for BP, and the specificities were 99.3%, 99.1%, and 99.6%, respectively. The sensitivities as compared with TRUST were 87.2% for WB, 85.8% for FB, and 88.4% for BP, and the specificities were 94.4%, 96.1%, and 95.0%, respectively. For specimens with a TRUST titer of 1:4 or higher, the sensitivities were 100.0% for WB, 97.8% for FB, and 99.6% for BP. Conclusions. DPP test shows good sensitivity and specificity in detecting treponemal and nontreponemal antibodies in 3 kinds of specimens. It is hoped that this assay can be considered as an alternative in the diagnosis of syphilis, particularly in resource-limited areas. PMID:23132172

  15. Re-examination of the Neisser—Wechsberg (antibody prozone) phenomenon

    PubMed Central

    Muschel, L. H.; Gustafson, Linda; Larsen, Linda J.

    1969-01-01

    Although the Neisser—Wechsberg phenomenon resembles the inhibition of agglutination systems by excess antibody, the experimental results have indicated that with heat-inactivated antiserum the phenomenon results both from an excess of specific antibody and of non-specific anti-complementary activity. Complement (C) has been shown to be fixed in the presence of the excess antiserum which inhibits the bactericidal reaction. The inhibition was overcome by an excess of the third complement component factors indicating that the excess of antiserum interfered with the activation or function of the components acting at one of the late steps in the reaction sequence. The prozone phenomenon was relatively slight when unheated antiserum was used or when sensitized organisms were washed to remove serum substances unrelated to antibody. Non-specific anti-complementary activity, therefore, is a major contributor to the prozone phenomenon. Both IgM and IgG fractions of rabbit antisera elicited a prozone although the former had relatively greater bactericidal than inhibitory activity. PMID:5352361

  16. Testing Eurasian wild boar piglets for serum antibodies against Mycobacterium bovis.

    PubMed

    Che' Amat, A; González-Barrio, D; Ortiz, J A; Díez-Delgado, I; Boadella, M; Barasona, J A; Bezos, J; Romero, B; Armenteros, J A; Lyashchenko, K P; Venteo, A; Rueda, P; Gortázar, C

    2015-09-01

    Animal tuberculosis (TB) caused by infection with Mycobacterium bovis and closely related members of the M. tuberculosis complex (MTC), is often reported in the Eurasian wild boar (Sus scrofa). Tests detecting antibodies against MTC antigens are valuable tools for TB monitoring and control in suids. However, only limited knowledge exists on serology test performance in 2-6 month-old piglets. In this age-class, recent infections might cause lower antibody levels and lower test sensitivity. We examined 126 wild boar piglets from a TB-endemic site using 6 antibody detection tests in order to assess test performance. Bacterial culture (n=53) yielded a M. bovis infection prevalence of 33.9%, while serum antibody prevalence estimated by different tests ranged from 19% to 38%, reaching sensitivities between 15.4% and 46.2% for plate ELISAs and between 61.5% and 69.2% for rapid immunochromatographic tests based on dual path platform (DPP) technology. The Cohen kappa coefficient of agreement between DPP WTB (Wildlife TB) assay and culture results was moderate (0.45) and all other serological tests used had poor to fair agreements. This survey revealed the ability of several tests for detecting serum antibodies against the MTC antigens in 2-6 month-old naturally infected wild boar piglets. The best performance was demonstrated for DPP tests. The results confirmed our initial hypothesis of a lower sensitivity of serology for detecting M. bovis-infected piglets, as compared to older wild boar. Certain tests, notably the rapid animal-side tests, can contribute to TB control strategies by enabling the setup of test and cull schemes or improving pre-movement testing. However, sub-optimal test performance in piglets as compared to that in older wild boar should be taken into account. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Agglutinates as recorders of fossil soil compositions. [of Apollo 17 lunar probes

    NASA Technical Reports Server (NTRS)

    Taylor, G. J.; Wentworth, S.; Warner, R. D.; Keil, K.

    1978-01-01

    The composition of agglutinates in polished sections of the Apollo 17 drill core was studied in an attempt to deduce the nature of the Taurus-Littrow valley regolith prior to the formation of the Camelot and Central Cluster craters. The agglutinate compositions in the soils differed from the host soil compositions except for samples from the North Massif. Local materials from the valley floor and the massifs appear to form the pre-Central Cluster regolith. It is also shown that chemical mixing models for bulk soil compositions can be misleading unless the petrologic characteristics of each soil are taken into account.

  18. Synthesis for Lunar Simulants: Glass, Agglutinate, Plagioclase, Breccia

    NASA Technical Reports Server (NTRS)

    Weinstein, Michael; Wilson, Stephen A.; Rickman, Douglas L.; Stoeser, Douglas

    2012-01-01

    The video describes a process for making glass for lunar regolith simulants that was developed from a patented glass-producing technology. Glass composition can be matched to simulant design and specification. Production of glass, pseudo agglutinates, plagioclase, and breccias is demonstrated. The system is capable of producing hundreds of kilograms of high quality glass and simulants per day.

  19. Design of a comprehensive biochemistry and molecular biology experiment: phase variation caused by recombinational regulation of bacterial gene expression.

    PubMed

    Sheng, Xiumei; Xu, Shungao; Lu, Renyun; Isaac, Dadzie; Zhang, Xueyi; Zhang, Haifang; Wang, Huifang; Qiao, Zheng; Huang, Xinxiang

    2014-01-01

    Scientific experiments are indispensable parts of Biochemistry and Molecular Biology. In this study, a comprehensive Biochemistry and Molecular Biology experiment about Salmonella enterica serovar Typhi Flagellar phase variation has been designed. It consisted of three parts, namely, inducement of bacterial Flagellar phase variation, antibody agglutination test, and PCR analysis. Phase variation was observed by baterial motility assay and identified by antibody agglutination test and PCR analysis. This comprehensive experiment can be performed to help students improve their ability to use the knowledge acquired in Biochemistry and Molecular Biology. Copyright © 2014 by The International Union of Biochemistry and Molecular Biology.

  20. The role of latex agglutination test for the etiological diagnosis of pleural effusion in children and adolescents.

    PubMed

    Camargos, Paulo; Fonseca, Ana Cristina; Amantéa, Sérgio; Oliveira, Elizabeth; Benfica, Maria das Graças; Chamone, Chequer

    2017-05-01

    The etiological diagnosis of pleural effusion is a difficult task because the diagnostic tools can only establish a definitive etiological diagnosis in at most 76% of cases. To verify the diagnostic accuracy of the latex agglutination test (LAT) for the etiological diagnosis of pleural effusions caused by Streptococcus pneumoniae and Haemophilus influenzae type b. After thoracocentesis, paired fresh samples of pleural fluid from 418 children and adolescents were included in this investigation. They were tested blindly and simultaneously through counterimmunoelectrophoresis (CIE) and LAT for both bacteria. Sensitivity, specificity, predictive values and likelihood ratios (LR) were calculated taking CIE as a reference standard. The sensitivity and specificity of LAT was 100% (95% confidence interval, 94.4%-100%) and 83.3% (95% confidence interval, 79.0%-87.0%), respectively, whereas the positive (calculated from Bayes' theorem) and negative predictive values were, respectively, lower than 1% and 100% (95% confidence interval, 98.8%-100%). Positive and negative LR were 6.0 (95% confidence interval, 4.7-7.6) and zero, respectively. Our results suggest that LAT is a useful tool for the etiological diagnosis of pleural effusion. It is a reliable, rapid, simple to perform and shows an excellent yield in our studied population, helping to prescribe appropriate antibiotics for this clinical condition. © 2015 John Wiley & Sons Ltd.

  1. Genetic and Mechanistic Evaluation for the Mixed-Field Agglutination in B3 Blood Type with IVS3+5G>A ABO Gene Mutation

    PubMed Central

    Wang, Wei-Ting; Sun, Chien-Feng

    2012-01-01

    Background The ABO blood type B3 is the most common B subtype in the Chinese population with a frequency of 1/900. Although IVS3+5G>A (rs55852701) mutation of B gene has been shown to associate with the development of B3 blood type, genetic and mechanistic evaluation for the unique mixed-field agglutination phenotype has not yet been completely addressed. Methodology/Principal Findings In this study, we analyzed 16 cases of confirmed B3 individuals and found that IVS3+5G>A attributes to all cases of B3. RT-PCR analyses revealed the presence of at least 7 types of aberrant B3 splicing transcripts with most of the transcripts causing early termination and producing non-functional protein during translation. The splicing transcript without exon 3 that was predicted to generate functional B3 glycosyltransferase lacking 19 amino acids at the N-terminal segment constituted only 0.9% of the splicing transcripts. Expression of the B3 cDNA with exon 3 deletion in the K562 erythroleukemia cells revealed that the B3 glycosyltransferase had only 40% of B1 activity in converting H antigen to B antigen. Notably, the typical mixed-field agglutination of B3-RBCs can be mimicked by adding anti-B antibody to the K562-B3 cells. Conclusions/Significance This study thereby demonstrates that both aberrant splicing of B transcripts and the reduced B3 glycosyltransferase activity contribute to weak B expression and the mixed-field agglutination of B3, adding to the complexity for the regulatory mechanisms of ABO gene expression. PMID:22624005

  2. Simple Tests for Rapid Detection of Canine Parvovirus Antigen and Canine Parvovirus-Specific Antibodies▿ †

    PubMed Central

    Marulappa, Shashidhara Y.; Kapil, Sanjay

    2009-01-01

    Canine parvovirus (CPV) is the number one viral cause of enteritis, morbidity, and mortality in 8-week-old young puppies. We have developed twin assays (slide agglutination test [SAT] for CPV antigen and slide inhibition test [SIT] for CPV antibody) that are sensitive, specific, cost-effective, generic for all genotypes of CPV, and provide instant results for CPV antigen detection in feces and antibody quantification in serum. We found these assays to be useful for routine applications in kennels with large numbers of puppies at risk. The results of these assays are available in 1 min and do not require any special instrumentation. SAT-SIT technology will find applications in rapid screening of samples for other hemagglutinating emerging viruses of animals and humans (influenza virus and severe acute respiratory syndrome coronavirus). PMID:18987166

  3. Passive haemagglutination test for antibodies against rabies virus*

    PubMed Central

    Gough, P. M.; Dierks, R. E.

    1971-01-01

    All the procedures now available for the measurement of rabies virus antibodies in serum have certain disadvantages. The serum neutralization test (SN), whether carried out by assay in mice or by the plaque-reduction technique, requires several days before the titrations are completed, necessitates special facilities for keeping large numbers of animals and tissue-culture plates, and is relatively expensive. A complement-fixation test is very insensitive, giving low titres in comparison with SN tests, and a haemagglutination-inhibition procedure is complicated by the presence of nonspecific reactions. A rabies passive haemagglutination technique (RPHA), developed to overcome many of these problems, is described. Titres obtained with human sera by the RPHA procedure correlated well with those obtained by SN tests. Both IgG and IgM classes of antibodies were measured by the RPHA procedure; however, it appeared to be more sensitive for detecting IgM than was the SN test and, therefore, gave higher titres for this class of immunoglobulins. PMID:5317009

  4. INRA, a new high-frequency antigen in the INDIAN (IN023) blood group system

    PubMed Central

    Joshi, Sanmukh R.; Sheladiya, Ankita; Mendapara-Dobariya, Kinjal V.

    2017-01-01

    BACKGROUND: The INDIAN blood group system comprises 4 antigens sensitive to enzymes and 2-aminoethyl isothiouronium bromide (AET). AIM: The patient's antibody was investigated for its specificity to the high-frequency antigens (HFA) of this system. MATERIAL AND METHODS: Low ionic strength solution (LISS)-tube/LISS-indirect antiglobulin test (IAT) methods were used. The patient's red blood cells (RBCs) were tested with antisera to HFA. Her antibody was tested with RBCs lacking the HFA. Furthermore, it was tested with RBCs as untreated or treated with enzyme or AET. The genetic sequence was studied for mutation in CD44 gene that encodes INDIAN antigens. RESULTS: The patient was grouped A1B, RhD+, antibody screening test positive, direct antiglobulin test negative. A negative autocontrol test had suggested to the alloantibody being present. Antibody had agglutinated RBCs in LISS-tube at RT and by LISS-IAT at 37°C. The RBCs of the 11-cell panel, those lacking HFA and from 50 random donors, were agglutinated by her antibody indicating its specificity to the HFA, though the RBCs of Lu (a-b-)/In (Lu) type showed a weaker reaction. The patient's RBCs were agglutinated by antisera to a number of the enzyme-sensitive HFA, including those of INDIAN blood groups. The antibody showed reduced reactivity with the RBCs treated with papain, chymotrypsin, and AET but resistant to trypsin and dithiothreitol. The patient's genetic sequence revealed a novel homozygous mutation 449G>A in exon 5 of CD44. CONCLUSION: The antibody to enzyme sensitive HFA was tested for serological and molecular genetics studies and found to be directed to the novel HFA, named as INRA of the INDIAN blood group system and was assigned a numerical symbol IN: 005 by the International Society of Blood Transfusion (ISBT). PMID:28970678

  5. INRA, a new high-frequency antigen in the INDIAN (IN023) blood group system.

    PubMed

    Joshi, Sanmukh R; Sheladiya, Ankita; Mendapara-Dobariya, Kinjal V

    2017-01-01

    The INDIAN blood group system comprises 4 antigens sensitive to enzymes and 2-aminoethyl isothiouronium bromide (AET). The patient's antibody was investigated for its specificity to the high-frequency antigens (HFA) of this system. Low ionic strength solution (LISS)-tube/LISS-indirect antiglobulin test (IAT) methods were used. The patient's red blood cells (RBCs) were tested with antisera to HFA. Her antibody was tested with RBCs lacking the HFA. Furthermore, it was tested with RBCs as untreated or treated with enzyme or AET. The genetic sequence was studied for mutation in CD44 gene that encodes INDIAN antigens. The patient was grouped A1B, RhD+, antibody screening test positive, direct antiglobulin test negative. A negative autocontrol test had suggested to the alloantibody being present. Antibody had agglutinated RBCs in LISS-tube at RT and by LISS-IAT at 37°C. The RBCs of the 11-cell panel, those lacking HFA and from 50 random donors, were agglutinated by her antibody indicating its specificity to the HFA, though the RBCs of Lu (a-b-)/In (Lu) type showed a weaker reaction. The patient's RBCs were agglutinated by antisera to a number of the enzyme-sensitive HFA, including those of INDIAN blood groups. The antibody showed reduced reactivity with the RBCs treated with papain, chymotrypsin, and AET but resistant to trypsin and dithiothreitol. The patient's genetic sequence revealed a novel homozygous mutation 449G>A in exon 5 of CD44 . The antibody to enzyme sensitive HFA was tested for serological and molecular genetics studies and found to be directed to the novel HFA, named as INRA of the INDIAN blood group system and was assigned a numerical symbol IN: 005 by the International Society of Blood Transfusion (ISBT).

  6. Differential serological testing by simultaneous indirect immunofluorescent antibody test in canine leishmaniosis and ehrlichiosis.

    PubMed

    Guillén Llera, J L; López García, M L; Martín Reinoso, E; De Vivar González, R

    2002-11-11

    A mixed indirect fluorescence antibody test (IFAT), based on cultured promastigotes Leishmania infantum and formol-inactivated suspension of cells infected with the bacteria Ehrlichia canis, was applied to make a differential diagnosis between canine ehrlichiosis and leishmaniosis. A titre greater than 80 was considered positive for antibodies to E. canis and suggestive of antibodies to L. infantum. Positive sera were titrated subsequently by serial dilutions to confirm antibodies positive to Leishmania and establishing the antibody titre of both pathogens. Fluorescence was absent with negative control sera and background staining was minimal. No serological cross-reactions between positive sera for L. infantum or E. canis were detected. Results obtained by mixed IFAT did not differ when the same serum IFAT standard was compared. The test showed equivalent sensitivity (100%). The specifities were 100% for L. infantum and 98.5% for E. canis. The equivalence in sensitivity was confirmed by calculating the correlation coefficient between IFAT standards and mixed IFAT (r>or=0.99 for both pathogens). The results of our investigations demonstrated that mixed IFAT is a specific means of establishing serological differential diagnosis of canine leishmaniosis and ehrlichiosis.

  7. Evaluation of ID-PaGIA syphilis antibody test.

    PubMed

    Naaber, Paul; Makoid, Ene; Aus, Anneli; Loivukene, Krista; Poder, Airi

    2009-01-01

    Laboratory diagnosis of syphilis is usually accomplished by serology. There are currently a large number of different commercial treponemal tests available that vary in format, sensitivity and specificity. To evaluate the ID-PaGIA Syphilis Antibody Test as an alternative to other specific treponemal tests for primary screening or confirmation of diagnosis. Serum samples from healthy adults (n = 100) were used for detection of specificity of ID-PaGIA. To evaluate sensitivity of ID-PaGIA serum samples (n = 101) from patients with confirmed or suspected syphilis were tested for syphilis antibodies with FTA-Abs IgM, ID-PaGIA, ELISA IgM and TPHA tests. No false-positive results were found with ID-PaGIA. Sensitivity of various treponemal tests was the following: FTA-Abs IgM: 95.5%, ID-PaGIA and ELISA IgM: 94%, and TPHA 75%. The positive and negative predictive values of ID-PaGIA were 100 and 89.5%, respectively. Compared with other treponemal tests ID-PaGIA has excellent sensitivity and specificity.

  8. Differential actions of proteinases and neuraminidase on mammalian erythrocyte surface and its impact on erythrocyte agglutination by concanavalin A.

    PubMed

    Sharma, Savita; Gokhale, Sadashiv M

    2012-12-01

    Action of proteinases viz. trypsin and chymotrypsin, and neuraminidase on intact erythrocyte membrane proteins and glycophorins (sialoglycoproteins) exposed to cell surface and its impact on lectin (concanavalin A)-mediated agglutination were studied in Homo sapiens (human), Capra aegagrus hircus (goat) and Bubalus bubalis (buffalo). Membrane proteins and glycophorins analysis by SDS-PAGE as visualized by coomassie brilliant blue and periodic acid-schiff stains, respectively, and agglutination behaviour revealed marked differences: 1) there were prominent dissimilarities in the number and molecular weights of glycophorins in human, goat and buffalo erythrocyte membranes; 2) proteinase action(s) on human and buffalo erythrocyte surface membrane proteins and glycophorins showed similarity but was found different in goat; 3) significant differences in erythrocyte agglutinability with concanavalin A can be attributed to differences in membrane composition and alterations in the surface proteins after enzyme treatment; 4) a direct correlation was found between degradation of glycophorins and concanavalin A agglutinability; 5) action of neuraminidase specifically indicated the negative role of cell surface sialic acids in determining concanavalin A agglutinability of goat and buffalo erythrocytes, similar to human. Present studies clearly indicate that there are some basic differences in human, goat and buffalo erythrocyte membrane proteins, especially with respect to glycophorins, which determine the concanavalin A-mediated agglutination in enzyme treated erythrocytes.

  9. Establishment and performance assessment of preparation technology of internal quality control products for blood transfusion compatibility testing.

    PubMed

    Yu, Yang; Ma, Chunya; Feng, Qian; Chen, Xin; Guan, Xiaozhen; Zhang, Xiaojuan; Chen, Linfeng; Lin, Zilin; Pan, Jichun; Zhang, Ting; Luo, Qun; Wang, Deqing

    2013-05-01

    The aim of this study was to establish and to optimize the preparation technology of whole blood internal quality control (IQC) products for blood transfusion compatibility testing. Several B-type RhD-negative blood samples collected from healthy donors were mixed. Two groups of whole blood IQC products, namely, the preservative solution group (PS group) and the saline group, were prepared. The agglutination intensity of IQC sample red cells and anti-B antibody, IgM anti-A antibody and reverse-typing A cell, IgG anti-D and O-type RhD-positive red cells, as well as free hemoglobin concentration in the supernatant of the two groups were detected. The erythrocytes in both groups were damaged to a certain extent during storage, but no evident (above moderate) hemolysis was observed in the stored sample within 42 days. The red cells remained structurally complete and the reaction activity of IgG anti-D reagent remained generally unchanged (P>0.05). Although the reaction activity oscillation of IgM anti-A reagent was observed, the agglutination intensity varied within an acceptable range of 1+. No difference was observed between the preparation methods of the samples, i.e., between the erythrocyte washed with saline and the one washed with red cell preservative solution (P>0.05). The long shelf life, low variance between tubes and stable antigen-antibody reaction activity of the whole blood IQC products prepared using the proposed method can meet the requirements of blood transfusion compatibility testing.

  10. Bioactive extracts of red seaweeds Pterocladiella capillacea and Osmundaria obtusiloba (Floridophyceae: Rhodophyta) with antioxidant and bacterial agglutination potential.

    PubMed

    de Alencar, Daniel Barroso; de Carvalho, Fátima Cristiane Teles; Rebouças, Rosa Helena; Dos Santos, Daniel Rodrigues; Dos Santos Pires-Cavalcante, Kelma Maria; de Lima, Rebeca Larangeira; Baracho, Bárbara Mendes; Bezerra, Rayssa Mendes; Viana, Francisco Arnaldo; Dos Fernandes Vieira, Regine Helena Silva; Sampaio, Alexandre Holanda; de Sousa, Oscarina Viana; Saker-Sampaio, Silvana

    2016-04-01

    To evaluate the antioxidant, antibacterial and bacterial cell agglutination activities of the hexane (Hex) and 70% ethanol (70% EtOH) extracts of two species of red seaweeds Pterocladiella capillacea (P. capillacea) and Osmundaria obtusiloba. In vitro antioxidant activity was determined by DPPH radical scavenging assay, ferric-reducing antioxidant power assay, ferrous ion chelating assay, β-carotene bleaching assay and total phenolic content quantification. Antimicrobial activity was tested using the method of disc diffusion on Mueller-Hinton medium. The ability of algal extracts to agglutinate bacterial cells was also tested. The 70% EtOH extract of the two algae showed the highest values of total phenolic content compared to the Hex extract. The results of DPPH for both extracts (Hex, 70% EtOH) of Osmundaria obtusiloba (43.46% and 99.47%) were higher than those of P. capillacea (33.04% and 40.81%) at a concentration of 1000 μg/mL. As for the ferrous ion chelating, there was an opposite behavior, extracts of P. capillacea had a higher activity. The extracts showed a low ferric-reducing antioxidant power, with optical density ranging from 0.054 to 0.180. Antioxidant activities of all extracts evaluated for β-carotene bleaching were above 40%. There was no antibacterial activity against bacterial strains tested. However, the extracts of both species were able to agglutinate bacterial Gram positive cells of Staphylococcus aureus and Gram negative cells of Escherichia coli, multidrug-resistant Salmonella and Vibrio harveyi. This is the first report of the interaction between these algal extracts, rich in natural compounds with antioxidant potential, and Gram positive and Gram negative bacterial cells. Copyright © 2016 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

  11. A rapid immunochromatographic test strip for detecting rabies virus antibody.

    PubMed

    Wang, Hualei; Feng, Na; Yang, Songtao; Wang, Chengyu; Wang, Tiecheng; Gao, Yuwei; Su, Jianqing; Zheng, Xuexing; Hou, Xiaoqiang; Huang, Hainan; Yang, Ruimei; Zou, Xiaohuan; Huang, Geng; Xia, Xianzhu

    2010-12-01

    An immunochromatographic test strip (ICTS) for detecting antibodies to rabies virus was developed, using colloidal gold particles labeled with rabies virus glycoprotein as the tracer. The assay was evaluated using sera from dogs immunized with various commercial rabies vaccines, or from dogs in the clinics and sera from dogs immunized with vaccines against pathogens other than rabies virus, and negative sera from a wide variety of animal sources, including dogs, mice, and cats which had never been vaccinated. The ICTS was found to be highly specific for antibodies against rabies virus, with a detection limit of 0.5IU/ml as measured by the fluorescent antibody virus neutralization (FAVN) test. Compared with the FAVN test, the specificity and sensitivity of ICTS were 98.2% and 90.4%, respectively. There was an excellent agreement between results obtained by the ICTS and FAVN tests (kappa=0.888). Strips stored at 4°C in a plastic bag with a desiccant retained their specificity and sensitivity for at least 15 months, and strips stored at ambient temperature remained stable for 12 months. The immunochromatographic test strip may therefore be useful for clinical laboratories lacking specialized equipment and for diagnosis in the field for rapid detection of rabies virus-specific antibodies. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Indirect micro-immunofluorescence test for detecting type-specific antibodies to herpes simplex virus.

    PubMed

    Forsey, T; Darougar, S

    1980-02-01

    A rapid indirect micro-immunofluorescence test capable of detecting and differentiating type-specific antibodies to herpes simplex virus is described. The test proved highly sensitive and, in 80 patients with active herpes ocular infection, antibody was detected in 94%. No anti-herpes antibody was detected in a control group of 20 patients with adenovirus infections. Testing of animal sera prepared against herpes simplex virus types 1 and 2 and of human sera from cases of ocular and genital herpes infections showed that the test can differentiate antibodies to the infecting serotypes. Specimens of whole blood, taken by fingerprick, and eye secretions, both collected on cellulose sponges, could be tested by indirect micro-immunofluorescence. Anti-herpes IgG, IgM, and IgA can also be detected.

  13. Tailoring Antibody Testing and How to Use it in the Calculated Panel Reactive Antibody Era: The Northwestern University Experience

    PubMed Central

    Tambur, Anat R.; Leventhal, Joseph; Kaufman, Dixon B.; Friedewald, John; Miller, Joshua; Abecassis, Michael M.

    2014-01-01

    Background Patients with human leukocyte antigen antibodies constitute a significantly disadvantaged population among those awaiting renal transplantation. We speculated that more understanding of the patients’ antibody makeup would allow a more “immunologic” evaluation of crossmatch data, facilitate the use of virtual crossmatch (XM), and lead to more transplantability of these patients. Methods We retrospectively compared the transplantability and transplant outcome of two consecutive patient populations transplanted in our center. Group I (n=374) was evaluated using solid-phase base testing for determination of percentage panel reactive antibody (“PRA screen”) with limited antibody identification testing. Group II (n=333) was tested in a more comprehensive manner with major emphasis on antibody identification, antibody strength assignment, and the use of pronase for crossmatch. Results Given this approach, 49% (166/333) of the transplanted patients in group II were sensitized compared with 40% (150/374) of the recipients in group I; P=0.012. Transplant outcome at 1-year posttransplant was similar in both groups. Conclusions We conclude that comprehensive evaluation of human leukocyte antigen sensitization and application of immunologic in analyzing compatibility between donor and recipient can increase the transplantability of sensitized patients while maintaining similar outcome. Our approach is in line with United Network for Organ Sharing new guidelines for calculated panel reactive antibody and virtual XM analysis. We hope this report will prompt additional transplant programs to consider how they will use the new United Network for Organ Sharing algorithms. PMID:18946342

  14. Rapid, whole blood diagnostic test for detecting anti-hantavirus antibody in rats.

    PubMed

    Amada, Takako; Yoshimatsu, Kumiko; Yasuda, Shumpei P; Shimizu, Kenta; Koma, Takaaki; Hayashimoto, Nobuhito; Gamage, Chandika D; Nishio, Sanae; Takakura, Akira; Arikawa, Jiro

    2013-10-01

    Hantavirus is a causative agent of rodent-borne viral zoonoses, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome. Seoul virus (SEOV) is a causative agent of urban and laboratory rat-associated HFRS worldwide. Surveillance of rodents has been done mainly by serological detection of hantavirus-specific antibodies by enzyme linked immunosorbent assay (ELISA) and immunofluorescent antibody assay (IFA). An immunochromatographic (ICG) test was developed with the N-terminal 103 amino acids of nucleocapsid protein of Hantaan virus expressed by Escherichia coli as an antigen to detect IgG antibody specific to hantavirus in sera from Rattus sp. animals. Antibody-detecting sensitivity of the ICG test was the same as that of ELISA and about 100-times higher than that of IFA. Overall sensitivities and specificities of the ICG test in comparison to ELISA and IFA for sera from 192 urban rats and 123 laboratory rats were 99.3% and 100%, respectively. Diluted whole blood samples without separation could be used for the ICG test. The ICG test enabled detection of antibodies to SEOV, Hantaan, Dobrava/Belgrade, and Thailand viruses, which are causative agents of HFRS throughout Eurasia. The ICG test is a rapid, simple and safe method for diagnosis of SEOV infection in rats. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. A simple nucleic acid hybridization/latex agglutination assay for the rapid detection of polymerase chain reaction amplicons.

    PubMed

    Vollenhofer-Schrumpf, Sabine; Buresch, Ronald; Schinkinger, Manfred

    2007-03-01

    We have developed a new method for the detection of nucleic acid hybridization, based on a simple latex agglutination test that can be evaluated by the unaided eye. Nucleic acid, e.g., a polymerase chain reaction (PCR) product, is denatured and incubated with polystyrene beads carrying covalently bound complementary oligonucleotide sequences. Hybridization of the nucleic acids leads to aggregation of the latex particles, thereby verifying the presence of target sequence. The test is performed at room temperature, and results are available within 10 min. As a proof of principle, the hybridization/latex agglutination assay was applied to the detection of purified PCR fragments either specific for Salmonella spp. or a synthetic sequence, and to the detection of Salmonella enterica in artificially contaminated chicken samples. A few nanograms of purified PCR fragments were detectable. In artificially contaminated chicken samples, 3 colony-forming units (cfu)/25 g were detected in one of three replicates, and 30 cfu/25 g were detected in both of two replicates when samples for PCR were taken directly from primary enrichment, demonstrating the practical applicability of this test system. Even multiplex detection might be achievable. This novel kind of assay could be useful for a range of applications where hybridization of nucleic acids, e.g., PCR fragments, is to be detected.

  16. Incomplete antibodies and immunoglobulin characterization in adult urodeles, Pleurodeles waltlii Michah. and Triturus alpestris Laur.

    PubMed Central

    Tournefier, A

    1975-01-01

    Humoral immunoglobulin synthesis has been studied in two adult urodeles, Pleurodeles waltlii Michah. and Triturus alpestris Laur. following SRBC immunization. The specific antibody response is detected after a long period of immunization and is due exclusively to 'incomplete' antibodies which are unable to induce agglutination. The antibody titre is essentially dependent on the number of stimulations rather than on the dose or nature of the antigen (papainized or normal erythrocytes). Antibodies are detected in only 50 per cent of the immunized animals, 50 per cent never respond. This suggests that the latter group does not possess the genetic equipment (Ir genes) to recognize the antigenic determinants and to synthesize the corresponding antibodies. The sedimentation coefficient of the synthesized immunoglobulins was investigated by sucrose density gradient centrifugation and their characterization was carried out by starch and polyacrylamide gel electrophoresis. With this peculiar antigen even after a booster injection, only one class of immunoglobulin, an 18-2S IgM could be detected. PMID:49296

  17. [Analysis on willingness to pay for HIV antibody saliva rapid test and related factors].

    PubMed

    Li, Junjie; Huo, Junli; Cui, Wenqing; Zhang, Xiujie; Hu, Yi; Su, Xingfang; Zhang, Wanyue; Li, Youfang; Shi, Yuhua; Jia, Manhong

    2015-02-01

    To understand the willingness to pay for HIV antibody saliva rapid test and its influential factors among people seeking counsel and HIV test, STD clinic patients, university students, migrant people, female sex workers (FSWs), men who have sex with men (MSM) and injecting drug users (IDUs). An anonymous questionnaire survey was conducted among 511 subjects in the 7 groups selected by different sampling methods, and 509 valid questionnaires were collected. The majority of subjects were males (54.8%) and aged 20-29 years (41.5%). Among the subjects, 60.3% had education level of high school or above, 55.4% were unmarried, 37.3% were unemployed, 73.3% had monthly expenditure <2 000 Yuan RMB, 44.2% had received HIV test, 28.3% knew HIV saliva test, 21.0% were willing to receive HIV saliva test, 2.0% had received HIV saliva test, only 1.0% had bought HIV test kit for self-test, and 84.1% were willing to pay for HIV antibody saliva rapid test. Univariate logistic regression analysis indicated that subject group, age, education level, employment status, monthly expenditure level, HIV test experience and willingness to receive HIV saliva test were correlated statistically with willingness to pay for HIV antibody saliva rapid test. Multivariate logistic regression analysis showed that subject group and monthly expenditure level were statistically correlated with willingness to pay for HIV antibody saliva rapid test. The willingness to pay for HIV antibody saliva rapid test and acceptable price of HIV antibody saliva rapid test varied in different areas and populations. Different populations may have different willingness to pay for HIV antibody saliva rapid test;the affordability of the test could influence the willingness to pay for the test.

  18. The relationship of the lunar regolith less than 10 micrometer fraction and agglutinates. I - A model for agglutinate formation and some indirect supportive evidence

    NASA Technical Reports Server (NTRS)

    Papike, J. J.; Simon, S. B.; White, C.; Laul, J. C.

    1982-01-01

    The first part of a study of the 'less than 10 micrometer' soil fraction and agglutinates is concerned with the chemical systematics of the considered fraction of lunar soils, taking into account a model for agglutinate formation based on the fusion of the finest fraction (FFF). Attention is given to some evidence which supports the FFF model. The evidence is based on some indirect approaches to an estimation of the composition of the fused soil component. It is found that the 'less than 10 micrometer' soil fraction from all Apollo sites except Apollo 16 (which can be explained) is more feldspathic and enriched in incompatible elements (e.g., K and Th) than the bulk soil. It is concluded that these systematics result from simple comminution in which feldspar breaks down to finer sizes than pyroxene and olivine and the fine-grained incompatible-element-enriched mesostasis concentrates in the 'less than 10 micrometer' soil fraction.

  19. Pheromone induction of agglutination in Saccharomyces cerevisiae a cells

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

    Terrance, K.; Lipke, P.N.

    1987-10-01

    a-Agglutinin, the cell surface sexual agglutinin of yeast a cells, was assayed by its ability to bind its complementary agglutinin, ..cap alpha..-agglutinin. The specific binding of /sup 125/I-..cap alpha..-agglutinin to a cells treated with the sex pheromone ..cap alpha..-factor was 2 to 2.5 times that of binding to a cells not treated with ..cap alpha..-factor. Competition with unlabeled ..cap alpha..-agglutinin revealed that the increased binding was due to increased cell surface expression of a-agglutinin, with no apparent change in the binding constant. The increase in site number was similar to the increase in cellular agglutinability. Increased expression of a-agglutinin followedmore » the same kinetics as the increase in cellular agglutinability, with a 10-min lag followed by a 15- to 20-min response time. Induction kinetics were similar in cells in phases G1 and G2 of the cell cycle. Maximal expression levels were similar in cells treated with excess pheromone and in cells exposed to pheromone after destruction of constitutively expressed a-agglutinin.« less

  20. Shared epitopes of glycoprotein A and protein 4.1 defined by antibody NaM10-3C10.

    PubMed

    Rasamoelisolo, M; Czerwinski, M; Willem, C; Blanchard, D

    1998-06-01

    We have produced the murine monoclonal antibody (MAb) NaM70-3C10 (IgM) from splenocytes of mice immunized with human red blood cells (RBCs). The MAb agglutinated untreated as well as trypsin, chymotrypsin, neuraminidase, or ficin-treated RBCs from controls. In contrast, control RBCs treated with papaine or bromelaine were not agglutinated. On immunoblots, the MAb bound to glycophorin A (GPA) and to a 80 kDa protein identified as protein 4.1. Analysis by agglutination of variant RBCs carrying hybrid glycophorins made of the N-terminus (amino acids 1-58) of GPA and of the C-terminus (amino acids 27-72) of glycophorin B (GPB) and competition-inhibition test using purified GPA and a synthetic peptide corresponding to the amino acid sequence 48-58 of GPA demonstrated that the epitope is located within residues 48-58 of GPA. Epitope analysis with immobilized peptides showed that the MAb recognizes the sequence 53Pro-Pro-Glu-Glu-GIu58 of GPA. A homologous sequence is also present within amino acids 395 to 405 of protein 4.1. Finally, the MAb bound to 16 kDa chymotryptic peptide of protein 4.1, which carries the above amino acid sequence. In conclusion, it may be assumed that NaM70-3C10 specifically recognizes a common epitope on the extracellular domain of GPA and on the intracellular protein 4.1; this specificity explains the persistence of the 80 kDa band on blots when RBCs are treated with papain.

  1. 21 CFR 866.5785 - Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) antibody (ASCA) test systems. 866.5785 Section 866.5785 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test Systems § 866.5785 Anti-Saccharomyces cerevisiae (S. cerevisiae) antibody (ASCA) test systems...

  2. Avian P1 antigens inhibit agglutination mediated by P fimbriae of uropathogenic Escherichia coli.

    PubMed Central

    Johnson, J R; Swanson, J L; Neill, M A

    1992-01-01

    Whole egg white from pigeon, dove, and cockatiel eggs, as well as the ovomucoid fraction of pigeon egg white, exhibited strong P1 antigenic activities and inhibited agglutination of human P1 erythrocytes and of digalactoside-coated latex beads by P-fimbriated Escherichia coli strains. In contrast, chicken egg white exhibited only weak P1 antigenic activity and had little impact on P-fimbrial agglutination. These preparations did not affect hemagglutination by E. coli strains expressing mannose-resistant adhesins other than P fimbriae, i.e., Dr, F1845, and S adhesins. Human anti-P1 serum diminished the P-fimbrial inhibitory activities of pigeon egg white and pigeon ovomucoid. Pigeon ovomucoid was equipotent on a molar basis with globoside, and the pigeon, dove, and cockatiel egg white preparations were equipotent with each other in P-fimbrial inhibition. Incubation of p erythrocytes in whole egg whites or in pigeon ovomucoid did not render them agglutinable by P-fimbriated bacteria, whereas incubation in globoside did. These data demonstrate that whole egg whites (and their ovomucoid fraction) from members of the families Columbidae (pigeons and doves) and Psittacidae (parrots) specifically and potently inhibit P-fimbrial agglutination, probably by providing P1 antigen as a receptor for the P-fimbrial adhesin. Avian egg white preparations may facilitate adhesin characterization of wild-type uropathogenic strains and may useful in preventing upper urinary tract infections due to P-fimbriated E. coli. PMID:1346125

  3. Assessment of a fluorescent antibody test for the detection of antibodies against epizootic bovine abortion.

    PubMed

    Blanchard, Myra T; Anderson, Mark L; Hoar, Bruce R; Pires, Alda F A; Blanchard, Patricia C; Yeargan, Bret V; Teglas, Mike B; Belshaw, Margaret; Stott, Jeffery L

    2014-09-01

    The current study was directed at developing and validating an indirect fluorescent antibody test (IFAT) capable of detecting antibodies specific for the agent of epizootic bovine abortion (aoEBA). Sensitivity and specificity was determined by comparing antibody titers from 114 fetuses infected with aoEBA with 68 fetuses diagnosed with alternate infectious etiologies. Data established specificity at 100% and sensitivity at 94.7% when cutoff criteria for a positive test were assigned at a titer of ≥1,000. Potential cross-reactivity was noted in samples from 3 fetuses with antibody titers of 10 or100; all were infected with Gram-positive organisms. The remaining 65 fetuses infected with microbes other than aoEBA, and an additional 12 negative reference sera, did not have detectable titers. The IFAT-based serology assay is rapid, reproducible, and unaffected by fluid color or opacity. Total fetal immunoglobulin (Ig)G was also evaluated as an aid for diagnosing EBA. Significantly higher concentrations of IgG were identified in fetuses infected with aoEBA as compared to those with alternate infectious etiologies. The presence of IgG is a sensitive indicator of EBA and increases the specificity of FAT-based serologic diagnosis when titers are 10 or 100. Taken together, serology and IgG analyses suggest that the incidence of EBA may be underestimated. © 2014 The Author(s).

  4. Detection of Antibodies to Brucella Cytoplasmic Proteins in the Cerebrospinal Fluid of Patients with Neurobrucellosis

    PubMed Central

    Baldi, Pablo C.; Araj, George F.; Racaro, Graciela C.; Wallach, Jorge C.; Fossati, Carlos A.

    1999-01-01

    The diagnosis of human neurobrucellosis usually relies on the detection of antibodies to Brucella lipopolysaccharide (LPS) in cerebrospinal fluid (CSF) by agglutination tests or enzyme-linked immunosorbent assay (ELISA). Here we describe the detection of immunoglobulin G (IgG) to cytoplasmic proteins (CP) of Brucella spp. by ELISA and Western blotting in seven CSF samples from five patients with neurobrucellosis. While IgG to CP (titers of 200 to 12,800) and IgG to LPS (800 to 6,400) were found in the CSF of these patients, these antibodies were not detected in CSF samples from two patients who had systemic brucellosis without neurological involvement. The latter, however, had serum IgG and IgM to both LPS and CP. No reactivity to these antigens was found in CSF samples from 14 and 20 patients suffering from nonbrucellar meningitis and noninfectious diseases, respectively. These findings suggest that, in addition to its usefulness in the serological diagnosis of human systemic brucellosis, the ELISA with CP antigen can be used for the specific diagnosis of human neurobrucellosis. PMID:10473531

  5. Antibody Prevalence and Isolation of Viable Toxoplasma gondii from Raptors in the Southeastern USA.

    PubMed

    Love, David; Kwok, Oliver C; Verma, Shiv Kumar; Dubey, Jitender P; Bellah, Jamie

    2016-07-01

    Raptors are good indicators of the prevalence of Toxoplasma gondii in the environment because they prey on small mammals and birds. These prey species are a major source of infection in domestic cats ( Felis catus ), which shed the environmentally resistant oocysts. We assessed T. gondii infection in 281 opportunistically available raptors at a rehabilitation facility between 2012 and 2014. Antibodies to T. gondii were assayed by a modified agglutination test (cutoff 1:25) and found in serum of 22/71 Red-tailed Hawks ( Buteo jamaicensis ), 25/54 Barred Owls ( Strix varia ), 9/41 Red-shouldered Hawks ( Buteo lineatus ), 13/28 Great Horned Owls ( Bubo virginianus ), 6/20 Broad-winged Hawks ( Buteo platypterus ), 2/16 Eastern Screech Owls (Megascops asio), 12/13 Bald Eagles ( Haliaeetus leucocephalus ), 6/12 Cooper's Hawks ( Accipiter cooperii ), 1/8 Black Vultures ( Coragyps atratus ), and 1/1 Golden Eagle ( Aquila chrysaetos ). Antibodies were not detected in 5 Barn Owls ( Tyto alba ), 3 American Kestrels ( Falco sparverius ), 1 Mississippi Kite ( Ictinia mississippiensis ), and 1 Osprey ( Pandion haliaetus ). Viable T. gondii was isolated from the tissues of 1 antibody-positive Barred Owl and identified as a strain having type II alleles at all 10 loci tested, except one (ToxoDB polymerase chain reaction-restriction fragment length polymorphism genotype 3). Type II strain is the most common strain in the US. Results of this study indicate a high prevalence of T. gondii in some raptor species and the first reported genotyping from a Barred Owl.

  6. Epizoological Survey of Certain Endemic Diseases in the Southern Part of the Great Salt Lake Desert.

    DTIC Science & Technology

    1959-06-30

    Rocky Mountain spotted fever , Rickettsia rickettsii; Q fever, Coxiella burneti; and psittacosis. The wildlife and cattle sera were tested for...complement-fixing antibodies for Q fever, Rocky Mountain spotted fever and the psittacosis-Lymphogranuloma group; and agglutinating antibodies for tularemia and brucellosis.

  7. Interaction forces between red cells agglutinated by antibody. II. Measurement of hydrodynamic force of breakup.

    PubMed Central

    Tha, S P; Shuster, J; Goldsmith, H L

    1986-01-01

    The expressions derived in the previous paper for the respective normal, F3, and shear forces, Fshear, acting along and perpendicular to the axis of a doublet of rigid spheres, were used to determine the hydrodynamic forces required to separate two red cell spheres of antigenic type B crosslinked by the corresponding antibody. Cells were sphered and swollen in isotonic buffered glycerol containing 8 X 10(-5) M sodium dodecyl sulfate, fixed in 0.085% glutaraldehyde, and suspended in aqueous glycerol (viscosity: 15-34 mPa s), containing 0.15 M NaCl and anti-B antibody from human hyperimmune antiserum at concentrations from 0.73 to 3.56 vol%. After incubating and mixing for 12 h, doublets were observed through a microscope flowing in a 178-micron tube by gravity feed between two reservoirs. Using a traveling microtube apparatus, the doublets were tracked in a constantly accelerating flow and the translational and rotational motions were recorded on videotape until breakup occurred. From a frame by frame replay of the tape, the radial position, velocity and orientation of the doublet were obtained and the normal and shear forces of separation at breakup computed. Both forces increased significantly with increasing antiserum concentration, the mean values of F3 increasing from 0.060 to 0.197 nN, and Fshear from 0.023 to 0.072 nN. There was no significant effect of glycerol viscosity on the forces of separation. It was not possible to determine whether the shear or normal force was responsible for doublet separation. Measurements of the mean dimensionless period of rotation, TG, of doublets in suspensions containing 0.73 and 2.40% antiserum undergoing steady flow were also made to test whether the spheres were rigidly linked or capable of some independent rotation. A fairly narrow distribution in TG about the value 15.64, predicted for rigidly-linked doublets, was obtained at both antiserum concentrations. Images FIGURE 1 PMID:3801572

  8. Monoclonal antibodies for serotyping the P fimbriae of uropathogenic Escherichia coli.

    PubMed Central

    de Ree, J M; Schwillens, P; van den Bosch, J F

    1986-01-01

    Monoclonal antibodies (MAbs) against seven serologically different P fimbriae (F7(1), F7(2), F8, F9, F11, F12, and F13) of uropathogenic Escherichia coli were tested for their ability to detect the P fimbriae on wild-type strains. In a plate agglutination test the MABs could detect the fimbriae on strains which expressed cloned fimbriae but not on wild-type strains. In a coagglutination test and in a whole-bacterium enzyme-linked immunosorbent assay the MAbs recognized the fimbriae on strains with cloned fimbriae and on wild-type strains. However, the coagglutination test has some disadvantages: only immunoglobulin G MAbs can be used, and the results cannot be read in an objective way. From these results, we concluded that the whole-bacterium enzyme-linked immunosorbent assay is the most convenient method for the determination of P fimbriae on wild-type E. coli strains. With this fast and easy method it is possible to do epidemiological studies on the distribution of P fimbriae among clinical isolates of uropathogenic E. coli and to extend the O:K:H serotype with the F serotype. PMID:2873149

  9. Assay of anti-HBs antibodies using a recombinant antigen and latex particle counting: comparison with five commercial tests.

    PubMed

    Galanti, L M; Cornu, C; Masson, P L; Robert, A R; Becheanu, D; Lamy, M E; Cambiaso, C L

    1991-05-01

    An assay of anti-HBs antibodies based on agglutination of latex particles coated with recombinant HBs-antigen was compared with Abbott radioimmunoassay (Abbott-RIA), which uses a human plasma-derived antigen. The population examined consisted of 76 Abbott-RIA anti-HBs-negative prevaccinated subjects and 1044 serum samples anti-HBs found positive by Abbott-RIA, including 283 samples of subjects vaccinated either with a human plasma-derived vaccine (group A; n = 180) or with a recombinant vaccine (group B; n = 103). Correlation coefficients between the two techniques were respectively r = 0.89 for the whole population (n = 1044), r = 0.98 in group A and r = 0.74 in group B. Anti-HBs titres were higher with latex than with RIA in group B as shown by the regression slopes: latex = 508 + 1.11 RIA in group A and latex = -1138 + 3.97 RIA in group B, suggesting that some vaccinated subjects from group B produced antibodies against epitopes proper to the recombinant antigen. In the prevaccinated population and in group A, the latex results were compared with those of radioimmunoassays (Abbott, Sorin) and enzyme immunoassays (Behring, Roche, Pasteur). Only the Roche-EIA detected anti-HBs in the prevaccinated subjects. The correlation between the various immunoassays was r greater than 0.96 only for values higher than 100 IU/l.

  10. 9 CFR 147.7 - Standard test procedures for mycoplasma. 5

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... plate agglutination test, the tube agglutination test, and the enzyme-linked immunosorbent assay (ELISA... accurate however, and are useful in evaluating serum samples that react with the ELISA, plate, and/or tube...

  11. 9 CFR 147.7 - Standard test procedures for mycoplasma. 5

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... plate agglutination test, the tube agglutination test, and the enzyme-linked immunosorbent assay (ELISA... accurate however, and are useful in evaluating serum samples that react with the ELISA, plate, and/or tube...

  12. 9 CFR 147.7 - Standard test procedures for mycoplasma. 5

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... plate agglutination test, the tube agglutination test, and the enzyme-linked immunosorbent assay (ELISA... accurate however, and are useful in evaluating serum samples that react with the ELISA, plate, and/or tube...

  13. 9 CFR 147.7 - Standard test procedures for mycoplasma. 5

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... plate agglutination test, the tube agglutination test, and the enzyme-linked immunosorbent assay (ELISA... accurate however, and are useful in evaluating serum samples that react with the ELISA, plate, and/or tube...

  14. 9 CFR 147.7 - Standard test procedures for mycoplasma. 5

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... plate agglutination test, the tube agglutination test, and the enzyme-linked immunosorbent assay (ELISA... accurate however, and are useful in evaluating serum samples that react with the ELISA, plate, and/or tube...

  15. Antimicrobial Action and Cell Agglutination by the Eosinophil Cationic Protein Are Modulated by the Cell Wall Lipopolysaccharide Structure

    PubMed Central

    Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M. Victòria

    2012-01-01

    Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination. PMID:22330910

  16. Antimicrobial action and cell agglutination by the eosinophil cationic protein are modulated by the cell wall lipopolysaccharide structure.

    PubMed

    Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M Victòria; Torrent, Marc; Boix, Ester

    2012-05-01

    Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination.

  17. Long-term antibody responses of cats fed toxoplasma gondii tissue cysts.

    PubMed

    Dubey, J P; Lappin, M R; Thulliez, P

    1995-12-01

    As part of a long-term study on immunity to oocyst shedding, 12 4-6-mo-old cats were inoculated orally with tissue cysts of the ME-49 strain (6 cats) or the TS-2 strain (6 cats) of Toxoplasma gondii. Two cats fed the ME-49 strain died or were killed because of acute toxoplasmosis 12 and 13 days after inoculation (DAI), respectively. On day 39 after primary infection, 5 cats (2 infected with the ME-49 strain and 3 infected with the TS-2 strain) were challenged orally with tissue cysts of the ME-49 strain. One cat died following rechallenge infection due to causes unrelated to toxoplasmosis. Seventy-seven months after primary infection, the remaining 9 cats were challenged orally with tissue cysts of the P89 strain of T. gondii. Blood samples were obtained weekly or monthly and sera were analyzed for antibodies to T. gondii using the modified agglutination test (MAT), the Sabin-Feldman dye test (DT), and the enzyme-linked immunosorbent assay (ELISA) for IgM (IgM-ELISA) or IgG (IgG-ELISA). The MAT was performed using both formalin-fixed (FF) and acetone-fixed (AF) tachyzoites. The MAT (FF) was the most sensitive test; cats seroconverted within 14 DAI and high titers (> 10,000) persisted > 6 yr, although cats had no clinical signs. The MAT titers using the AF detected recent exposure and titers declined sharply after 2 mo postinoculation. DT and ELISA titers were lower and developed slower than MAT titers. Fluctuations in antibody titers were limited to 8-fold during the 6-yr observation period. Anamnestic serum antibody responses were seen in 2 cats after the final challenge, but not after first challenge.

  18. Clinico-laboratory aspects of anti-nuclear and anti-native DNA antibody tests.

    PubMed

    Webb, J

    1978-01-01

    Available techniques for detection of anti-nuclear antibodies are here briefly reviewed. The relatively insensitive LE cell test has been largely supplanted by the indirect immunofluorescent ANA test which should be reported in terms of titre and pattern. Specific measurement of nDNA antibodies is now a regular technique in SLE diagnosis and management.

  19. Recombinant blood group proteins for use in antibody screening and identification tests.

    PubMed

    Seltsam, Axel; Blasczyk, Rainer

    2009-11-01

    The present review elucidates the potentials of recombinant blood group proteins (BGPs) for red blood cell (RBC) antibody detection and identification in pretransfusion testing and the achievements in this field so far. Many BGPs have been eukaryotically and prokaryotically expressed in sufficient quantity and quality for RBC antibody testing. Recombinant BGPs can be incorporated in soluble protein reagents or solid-phase assays such as ELISA, color-coded microsphere and protein microarray chip-based techniques. Because novel recombinant protein-based assays use single antigens, a positive reaction of a serum with the recombinant protein directly indicates the presence and specificity of the target antibody. Inversely, conventional RBC-based assays use panels of human RBCs carrying a huge number of blood group antigens at the same time and require negative reactions of samples with antigen-negative cells for indirect determination of antibody specificity. Because of their capacity for single-step, direct RBC antibody determination, recombinant protein-based assays may greatly facilitate and accelerate the identification of common and rare RBC antibodies.

  20. A comparative study of Widal test with blood culture in the diagnosis of typhoid fever in febrile patients.

    PubMed

    Andualem, Gizachew; Abebe, Tamrat; Kebede, Nigatu; Gebre-Selassie, Solomon; Mihret, Adane; Alemayehu, Haile

    2014-09-17

    Typhoid fever is a major health problem in developing countries and its diagnosis on clinical ground is difficult. Diagnosis in developing countries including Ethiopia is mostly done by Widal test. However, the value of the test has been debated. Hence, evaluating the result of this test is necessary for correct interpretation of the result. The main aim of this study was to compare the result of Widal test and blood culture in the diagnosis of typhoid fever in febrile patients. Blood samples were collected from 270 febrile patients with symptoms clinically similar to typhoid fever and visiting St. Paul's General Specialized Hospitals from mid December 2010 to March 2011. Blood culture was used to isolate S.typhi and S.paratyphi. Slide agglutination test and tube agglutination tests were used for the determination of antibody titer. An antibody titer of ≥1:80 for anti TO and ≥1:160 for anti TH were taken as a cut of value to indicate recent infection of typhoid fever. One hundred and eighty six (68.9%) participants were females and eighty four (31.1%) were males. 7 (2.6%) cases of S. typhi and 4 (1.5%) cases of S. paratyphi were identified with the total prevalence of typhoid fever 4.1%. The total number of patients who have indicative of recent infection by either of O and H antigens Widal test is 88 (32.6%). The sensitivity, specificity, Positive predictive Value and Negative predictive Value of Widal test were 71.4%, 68.44%, 5.7% and 98.9% respectively. Widal test has a low sensitivity, specificity and PPV, but it has good NPV which indicates that negative Widal test result have a good indication for the absence of the disease.

  1. Immunogold-agglutination assay for direct detection of HPV-16 E6 and L1 proteins from clinical specimens.

    PubMed

    Bhattarakosol, Parvapan; Plaignam, Kamolwan; Sereemaspun, Amornpun

    2018-05-01

    HPV-16 infection is the most common cause of cervical cancer. As HPV-16 transforms the cell, E6 oncoprotein is over-expressed. Therefore, molecular detection of HPV-16 E6 mRNA is now being used for diagnosis and prediction of cancer development. Besides detecting E6 mRNA, a rapid lateral flow detecting the E6 protein using enzyme immunoassay is also now on market with a sensitivity of 53.5% for cervical intraepithelial neoplasia (CIN)-3 or more severe (CIN-3+). Here, an immunogold-agglutination assay was developed to detect not only HPV-16 E6 protein but also L1, a major capsid protein found in the productive stage of the virus. Evaluation of this test using HPV-16 DNA positive cervical samples showed that the HPV-16 E6 immunogold-agglutination assay results correlated well with the progression of the cervical lesions, i.e., 10.34% of CIN-1, 68.75% of CIN-3 and 80% of cancer (CaCx) and none for healthy normal samples. Interestingly, the HPV-16 L1 protein was found in most of the cases with cancer indicating the possibility of virion production. Immunogold-agglutination assay for E6 protein is simpler, easier to be performed with a sensitivity of 73.1% for CIN-3+ suggesting a good method for laboratory diagnostic use. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Laboratory tests on the effectiveness of oral vaccination of young children against typhoid and paratyphoid A and B

    PubMed Central

    Vlădoianu, I. R.; Dimache, G.; Antohi, S.; Vlădoianu, Constanța; Zarma, Ortansa

    1965-01-01

    In Romania, pre-school children are excluded from subcutaneous inoculation with typhoid and paratyphoid A and B vaccine. The authors have therefore investigated the possibility of giving them an oral vaccine. Laboratory tests were carried out on 30 children from 3 to 7 years of age. Samples of blood serum were collected before and after vaccination and subsequently tested for (1) seroprotection in chick embryos, (2) seroprotection in white mice, (3) titration of the agglutinating antibodies, and (4) electrophoretic pattern. The results obtained showed that the oral administration of the vaccine can, under the conditions used in the test, afford a considerable degree of protection to young children. PMID:14290078

  3. Use of commercial extenders and alternatives to prevent sperm agglutination for cryopreservation of brown bear semen.

    PubMed

    Gomes-Alves, S; Alvarez, M; Nicolas, M; Lopez-Urueña, E; Martínez-Rodríguez, C; Borragan, S; de Paz, P; Anel, L

    2014-08-01

    The objective of this study was to evaluate different bovine and canine commercial semen extenders for cryopreservation of brown bear ejaculates and the effect of semen collection directly into extender on sperm agglutination. Semen samples were obtained by electroejaculation from 13 adult males. In experiment 1, eleven ejaculates from eight bears were used to evaluate Bioxcell and Andromed as extenders, whereas in experiment 2, nine ejaculates from six bears were used to evaluate Triladyl canine, CaniPro, and Extender 2 as extenders. An extender specifically developed for brown bears (Test-Tris-fructose-egg yolk-glycerol, TTF-ULE/bear) served as a control extender in both experiments. After thawing, total and progressive sperm motility and sperm viability were greater (P < 0.05) for TTF-ULE/bear and Andromed extenders than for Bioxcell in experiment 1 and greater (P < 0.05) for TTF-ULE/bear extender than for Triladyl Canine, CaniPro, and Extender 2 in experiment 2. In experiment 3, addition of handling extender (TTF-H) to the semen collection tube for eight ejaculates from seven bears resulted in less (P < 0.05) sperm agglutination in fresh samples (score 0.5 ± 0.2 vs. 1.8 ± 0.4 in diluted and control samples, respectively) with no effect on pre-freeze and post-thawing semen quality. In conclusion, TTF-ULE/bear is the most suitable extender for brown bear semen cryopreservation, but comparable results can be obtained with the commercial extender Andromed. In addition, collection of ejaculates directly in TTF-H extender decreases sperm agglutination in fresh samples. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Is there a role for antibody testing in the diagnosis of invasive candidiasis?

    PubMed

    Quindós, Guillermo; Moragues, María Dolores; Pontón, José

    2004-03-01

    During the last decades, the use of antibody tests for the diagnosis of invasive mycoses has declined as a consequence of the general belief that they are insensitive and non-specific. However, there is a clear evidence that antibodies can be detected in highly immunodeficient patients (such as bone marrow transplant recipients), and that those antibodies are useful for the diagnosis. Antibody tests are currently in use as diagnostic tools for some primary mycoses, such as the endemic mycoses, aspergilloma, allergic bronchopulmonary aspergilosis and sporothrichosis. For invasive candidiasis, diagnostic methods must differentiate Candida colonization of mucous membranes or superficial infection from tissue invasion by this microorganism. Substantial progress has been made in diagnosis of invasive candidiasis with the development of a variety of methods for the detection of antibodies and antigens. However, no single test has found widespread clinical use and there is a consensus that diagnosis based on a single specimen lacks sensitivity. It is necessary to test sequential samples taken while the patient is at greatest risk for developing invasive candidiasis to optimize the diagnosis. Results obtained from a panel of diagnostic tests in association with clinical aspects will likely be the most useful strategy for early diagnosis and therapy.

  5. Cross-reactions between alpha-streptococci and Omniserum, a polyvalent pneumococcal serum, demonstrated by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination.

    PubMed Central

    Holmberg, H; Danielsson, D; Hardie, J; Krook, A; Whiley, R

    1985-01-01

    In recent years several groups have used serological methods to demonstrate pneumococcal capsular antigens in sputum. In the present study 123 strains of alpha-hemolytic streptococci (including 97 strains from sputum or pharyngeal specimens) were tested for cross-reactions with a polyvalent antipneumococcal serum (Omniserum). Representatives of the following species were included: Streptococcus bovis, S. equinus, S. intermedius, S. lactis, S. milleri, S. mitis, S. mutans, S. sobrinus, S. salivarius, S. sanguis, S. suis, and Aerococcus viridans. Serological reactions were detected by direct immunofluorescence, immunoelectroosmophoresis, and latex agglutination. Fifteen (12%) of the strains gave positive reactions by all three methods. Positive reactions were also observed with another 32 strains (26%) with two of the methods, whereas 37 strains (30%) gave positive reactions by just one technique. Altogether 84 (68%) strains gave positive reactions with one or more of the methods. Latex agglutination gave positive reactions with 26 (21%) strains compared with 57 (46%) in immunofluorescence and 63 (51%) in immunoelectroosmophoresis. Absorption of the antiserum with one alpha-hemolytic strain reduced but did not entirely eliminate the cross-reactions with five tested strains. These findings indicate a potential risk of cross-reactions with polyvalent antipneumococcal serum in tests carried out on sputa or other specimens which may be contaminated with alpha-hemolytic streptococci. PMID:3889046

  6. Detection of methicillin-resistant Staphylococcus aureus using a specific anti-PBP2a chicken IgY antibody.

    PubMed

    Yamada, Keiko; Wanchun, Jin; Ohkura, Teruko; Murai, Atsushi; Hayakawa, Reina; Kinoshita, Keiji; Mizutani, Makoto; Okamoto, Akira; Namikawa, Takao; Ohta, Michio

    2013-01-01

    Immunodetection of methicillin-resistant Staphylococcus aureus (MRSA) by conventional methods employing mammalian immunoglobulins has unknown detection limits, and often yields false-positive results because of the presence of S. aureus protein A, which binds the Fc region of mammalian IgG. In this study, a new PBP2a-specific chicken IgY antibody was developed in inbred and conventional chickens, and used for the detection of MRSA using whole cell lysate samples. Our results showed that this chicken IgY antibody minimized the side effects of protein A. Moreover, enzyme-linked immunosorbent assay and immunochromatography systems were used with a monoclonal and polyclonal anti-PBP2a IgY antibody, clearly differentiating MRSA from methicillin-sensitive S. aureus and other methicillin-sensitive Staphylococcus spp. The detection limit of the immunochromatography was 10(8) colony-forming units; therefore, 1 colony on an agar plate was adequate to distinguish MRSA from non-MRSA. The specificity and sensitivity of this assay were almost similar to that of a commercially available latex agglutination test; however, the procedure used in this study was less complicated. The entire detection procedure, including sample preparation, takes only 20 min and does not require special equipment. Therefore, the use of this IgY antibody as a new tool for the detection of MRSA is highly recommended.

  7. Single-molecule detection of proteins with antigen-antibody interaction using resistive-pulse sensing of submicron latex particles

    NASA Astrophysics Data System (ADS)

    Takakura, T.; Yanagi, I.; Goto, Y.; Ishige, Y.; Kohara, Y.

    2016-03-01

    We developed a resistive-pulse sensor with a solid-state pore and measured the latex agglutination of submicron particles induced by antigen-antibody interaction for single-molecule detection of proteins. We fabricated the pore based on numerical simulation to clearly distinguish between monomer and dimer latex particles. By measuring single dimers agglutinated in the single-molecule regime, we detected single human alpha-fetoprotein molecules. Adjusting the initial particle concentration improves the limit of detection (LOD) to 95 fmol/l. We established a theoretical model of the LOD by combining the reaction kinetics and the counting statistics to explain the effect of initial particle concentration on the LOD. The theoretical model shows how to improve the LOD quantitatively. The single-molecule detection studied here indicates the feasibility of implementing a highly sensitive immunoassay by a simple measurement method using resistive-pulse sensing.

  8. The fluorescent treponemal antibody-absorption (FTA-ABS) test for syphilis.

    PubMed

    Hunter, E F

    1975-01-01

    The FTA test was developed at a time when immunofluorescence procedures were not well-defined. Through technique control and research, a modification of the FTA test, the FTA-ABS, has attained a position as one of the leading treponemal tests to confirm the reagin tests for syphilis. In this review of the FTA-ABS test, attention has been focused on reagent development, with the anticipation that reagent standardization may soon become a reality. The T. pallidum antigen obtained by extracting infected rabbit testicular tissue has evolved from a preparation in which the treponemes remained in the initial extracting fluid to a reagent that can be free of rabbit tissue and globulin. These washed antigen preparations improve visibility of the treponemes on the microscope slide, reduce background fluorescence, and reduce or prevent from occurring nonspecific reactions that are a result of tissue and globulin components. Both washed and nonwashed antigens are available commercially, and, to date, little differentiation has appeared on the product label. The predominant immunoglobulin that reacts with T. pallidum in the indirect fluorescent antibody tests appears to be IgG. This is the major immunoglobulin detected in the FTA-ABS test. IgM, although increased in early syphilis, is also increased in other clinical conditions. Several reports suggest that adult IgM detection in the present FTA-ABS test would be nonspecific. Until specific IgM antibody in adult syphilis can be detected without a risk to test specificity, the conjugate for the FTA-ABS test should continue to be an anti-IgG reagent. Class-specific, anti-IgG reagents are more expensive than other reagents; however, their use may eliminate the problem of nonspecificity resulting from IgM detection. Additionally, micromethods can be used to reduce cost, and this possibility should be investigated. The sorbent that contains an antigen to the Reiter treponeme may or may not specifically absorb the reactivity that

  9. Application of a spectrally filtered probing light beam and RGB decomposition of microphotographs for flow registration of ultrasonically enhanced agglutination of erythrocytes

    NASA Astrophysics Data System (ADS)

    Doubrovski, V. A.; Ganilova, Yu. A.; Zabenkov, I. V.

    2013-08-01

    We propose a development of the flow microscopy method to increase the resolving power upon registration of erythrocyte agglutination. We experimentally show that the action of a ultrasonic standing wave on an agglutinating mixture blood-serum leads to the formation of so large erythrocytic immune complexes that it seems possible to propose a new two-wave optical method of registration of the process of erythrocyte agglutination using the RGB decomposition of microphotographs of the flow of the mixture under study. This approach increases the reliability of registration of erythrocyte agglutination and, consequently, increases the reliability of blood typing. Our results can be used in the development of instruments for automatic human blood typing.

  10. Serosurvey of selected zoonotic agents in polar bears (Ursus maritimus)

    USGS Publications Warehouse

    Rah, H.; Chomel, B.B.; Follmann, Erich H.; Kasten, R.W.; Hew, C.H.; Farver, T.B.; Garner, G.W.; Amstrup, Steven C.

    2005-01-01

    Between 1982 and 1999 blood samples were collected from 500 polar bears (Ursus maritimus) captured in the Beaufort and Chukchi seas, to determine the seroprevalence of Brucella species, Toxoplasma gondii, and Trichinella species infections. The bears were classified into four age groups, cubs, yearlings, subadults and adults. Brucella and Toxoplasma antibodies were detected by agglutination (a buffered acidified card antigen and rapid automated presumptive test for brucellosis and a commercial latex agglutination test for toxoplasmosis); an ELISA was used to detect Thichinella antibodies. The overall seroprevalence of Brucella species was 5 per cent, and subadults and yearlings were 2.62 times (95 per cent confidence interval 1-02 to 6-82) more likely to be seropositive for Brucella species than adults and their cubs. The antibody prevalence for Toxoplasma gondii was 6 per cent, and for Trichinella species 55.6 per cent. The prevalence of antibodies to Trichinella species increased with age (P<0.001).

  11. The role of RhD agglutination for the detection of weak D red cells by anti-D flow cytometry.

    PubMed

    Grey, D E; Davies, J I; Connolly, M; Fong, E A; Erber, W N

    2005-04-01

    Anti-D flow cytometry is an accurate method for quantifying feto-maternal haemorrhage (FMH). However, weak D red cells with <1000 RhD sites are not detectable using this methodology but are immunogenic. As quantitation of RhD sites is not practical, an alternative approach is required to identify those weak D fetal red cells where anti-D flow cytometry is inappropriate. We describe a simple algorithm based on RhD agglutination and flow cytometry peak separation. All weak D (n = 34) gave weak agglutination with RUM-1 on immediate spin (grading agglutination (grading 3) was observed and the red cells were undetectable by flow cytometry. In the second subgroup, agglutination was strong (grading 4) and the red cells were detectable by anti-D flow cytometry. The accuracy of the quantitation was dependent on adequate separation of the weak D and RhD-negative peaks as in seven of 11 samples <1.11% of an expected 2% red cells were detectable. Monitoring RhD agglutination and flow cytometric peak separation are pivotal if anti-D flow cytometry is to be maintained as the primary technique for FMH quantitation in the routine laboratory.

  12. Evaluation of surveillance case definition in the diagnosis of leptospirosis, using the Microscopic Agglutination Test: a validation study.

    PubMed

    Dassanayake, Dinesh L B; Wimalaratna, Harith; Agampodi, Suneth B; Liyanapathirana, Veranja C; Piyarathna, Thibbotumunuwe A C L; Goonapienuwala, Bimba L

    2009-04-22

    Leptospirosis is endemic in both urban and rural areas of Sri Lanka and there had been many out breaks in the recent past. This study was aimed at validating the leptospirosis surveillance case definition, using the Microscopic Agglutination Test (MAT). The study population consisted of patients with undiagnosed acute febrile illness who were admitted to the medical wards of the Teaching Hospital Kandy, from 1st July 2007 to 31st July 2008. The subjects were screened to diagnose leptospirosis according to the leptospirosis case definition. MAT was performed on blood samples taken from each patient on the 7th day of fever. Leptospirosis case definition was evaluated in regard to sensitivity, specificity and predictive values, using a MAT titre >or= 1:800 for confirming leptospirosis. A total of 123 patients were initially recruited of which 73 had clinical features compatible with the surveillance case definition. Out of the 73 only 57 had a positive MAT result (true positives) leaving 16 as false positives. Out of the 50 who didn't have clinical features compatible with the case definition 45 had a negative MAT as well (true negatives), therefore 5 were false negatives. Total number of MAT positives was 62 out of 123. According to these results the test sensitivity was 91.94%, specificity 73.77%, positive predictive value and negative predictive values were 78.08% and 90% respectively. Diagnostic accuracy of the test was 82.93%. This study confirms that the surveillance case definition has a very high sensitivity and negative predictive value with an average specificity in diagnosing leptospirosis, based on a MAT titre of >or= 1: 800.

  13. Evaluation of IgY Antibody as a Polyspecific Coombs-Reagent.

    PubMed

    Calzado, Esteban Justo Gutiérrez; Heredia, Marlene Toledano; Duharte, Jeorge Fernadez; Zarnani, Amir-Hassan

    2017-01-01

    During the last twenty years, the extraction of specific egg yolk (IgY) antibodies from the immunized chickens has been accepted as a useful alternative to the immunization of mammals. The aim of the present study was immunizing the chickens with Human Umbilical Cord Serum (HUCS) and the extraction of specific anti-human globulins (IgG, C3b, and C3d) antibodies from egg yolk in order to obtain polyspecific Coombs reagent. The novelty of this work was the achievement of a polyclonal reagent through a very cheap alternative method in accordance with all ethical regulations required for obtaining it. Three Leghorn hens (21 weeks old) were immunized four times for a period of 66 days with 20uL of HUCS mixed with PBS/FCA or FIA each time. The extraction of IgY antibodies was performed according to the method of lipid precipitation of yolk and using water soluble fraction as the reagent material. The resulting IgY antibody was characterized by SDS-PAGE and immunoelectrophoresis and tested for the presence of hetero-agglutinins by means of direct agglutination using human erythrocytes of all blood groups treated with 0.1% papain and for indirect Coombs-test to evaluate its specificity to fractions (C3b, C3d, C4d) of human complement and human IgG, respectively. Our findings show, that, the reagent obtained contains IgY and other 3 proteins (SDS-PAGE), and reacts specifically with plasma proteins, that migrate in β and ϒ regions. In immunoelectrophoresis, in addition, there is the presence of low hetero-agglutinins levels in IgY-preparation (3 lots), and the possibility to produce high amount (more than 500 ml/egg ) of polyspecific Coombs-reagent in chickens is also discussed. IgY-preparation (3 lots), and the possibility to produce high amount (more than 500 ml/egg ) of polyspecific Coombs-reagent in chickens with the originality to achieve a polyclonal reagent through a very cheap alternative method in accordance with all ethical regulations required for obtaining it

  14. Neospora caninum and Toxoplasma gondii antibody prevalence in Alaska wildlife.

    PubMed

    Stieve, Erica; Beckmen, Kimberlee; Kania, Stephen A; Widner, Amanda; Patton, Sharon

    2010-04-01

    Free-ranging caribou and moose populations in some regions of Alaska undergo periodic declines in numbers. Caribou and moose are managed by the state as valuable resources for not only sustenance and subsistence, but also for cultural heritage. Incidence and prevalence of diseases that may impact herd health and recruitment from year to year are relevant to management decisions aimed to protect the long-term viability of these herds. Neospora caninum and Toxoplasma gondii are two apicomplexan parasites that can cause neurologic disease and abortions in their intermediate hosts and less frequently cause disease in their definitive hosts. The definitive hosts of N. caninum and T. gondii are canids and felids, respectively, and prevalence in the environment is in part dependent on maintenance of the life cycle through the definitive hosts. Serum samples from caribou (Rangifer tarandus, n=453), wolf (Canis lupus, n=324), moose (Alces alces, n=201), black-tailed deer (Odocoileus hemionus, n=55), coyote (Canis latrans, n=12), and fox (Vulpes vulpes, n=9) collected in Alaska were assayed for N. caninum- and T. gondii-reactive antibodies with an immunofluorescent antibody test (IFAT) and a modified agglutination test (MAT), respectively. Seroprevalence of N. caninum was greater in caribou (11.5%) than in wolves (9.0%), moose (0.5%), or black-tailed deer (0%). Seroprevalence of T. gondii was greater in wolves (17.8%) than in caribou (0.4%), moose (0%), or black-tailed deer (0%). Seroprevalence of N. caninum and T. gondii were 16.7% and 0.0% in coyotes and 0.0% and 12.5% in fox, but small sample sizes prevented further analysis. Antibodies to N. caninum in young caribou compared to adult caribou suggest that vertical transmission may be an important component of new infections in Alaskan caribou. The spatial distribution of antibody-positive individuals across Alaska may reflect differences in frequency of definitive hosts and alteration of predation patterns among regions.

  15. IMMUNOREACTIONS INVOLVING PLATELETS

    PubMed Central

    Shulman, N. Raphael

    1958-01-01

    Quantitative aspects of platelet agglutination and inhibition of clot retraction by the antibody of quinidine purpura were described. The reactions appeared to depend on formation of types of antibody-quinidine-platelet complexes which could fix complement but complement was not necessary for these reactions. Complement fixation was at least 10 times more sensitive than platelet agglutination or inhibition of clot retraction for measurement and detection of antibody activity. Although it has been considered that antibodies of drug purpura act as platelet lysins in the presence of complement and that direct lysis of platelets accounts for development of thrombocytopenia in drug purpura, the present study suggests that attachment of antibody produces a change in platelets which is manifested in vitro only by increased susceptibility to non-specific factors which can alter the stability of platelets in the absence of antibody. The attachment of antibody to platelets in vivo may only indirectly affect platelet survival. In contrast to human platelets, dog, rabbit, and guinea pig platelets, and normal or trypsin-treated human red cells did not agglutinate, fix complement, or adsorb antibody; and intact human endothelial cells did not fix complement or adsorb antibody. Rhesus monkey platelets were not agglutinated by the antibody but did adsorb antibody and fix complement although their activity in these reactions differed quantitatively from that of human platelets. Cinchonine could be substituted for quinidine in agglutination and inhibition of clot retraction reactions but quinine and cinchonidine could not. Attempts to cause passive anaphylaxis in guinea pigs with the antibody of quinidine purpura were not successful. PMID:13525580

  16. 21 CFR 866.3290 - Gonococcal antibody test (GAT).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Gonococcal antibody test (GAT). 866.3290 Section 866.3290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3290 Gonococcal...

  17. 21 CFR 866.3290 - Gonococcal antibody test (GAT).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gonococcal antibody test (GAT). 866.3290 Section 866.3290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3290 Gonococcal...

  18. 21 CFR 866.3290 - Gonococcal antibody test (GAT).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Gonococcal antibody test (GAT). 866.3290 Section 866.3290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3290 Gonococcal...

  19. 21 CFR 866.3290 - Gonococcal antibody test (GAT).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Gonococcal antibody test (GAT). 866.3290 Section 866.3290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3290 Gonococcal...

  20. 21 CFR 866.3290 - Gonococcal antibody test (GAT).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Gonococcal antibody test (GAT). 866.3290 Section 866.3290 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3290 Gonococcal...

  1. The generation of monoclonal antibodies and their use in rapid diagnostic tests

    USDA-ARS?s Scientific Manuscript database

    Antibodies are the most important component of an immunoassay. In these proceedings we outline novel methods used to generate and select monoclonal antibodies that meet performance criteria for use in rapid lateral flow and microfluidic immunoassay tests for the detection of agricultural pathogens ...

  2. Differentiation of the serological response to Yersinia enterocolitica and Brucella abortus in cattle

    PubMed Central

    Corbel, M. J.; Cullen, G. A.

    1970-01-01

    The serological responses of cattle to inoculation with Brucella abortus and Yersinia enterocolitica type IX were compared. Complete cross-reactions were found in serum agglutination, antiglobulin, complement fixation and Rose Bengal plate tests. The cross-reaction between Br. abortus and Y. enterocolitica IX was confirmed by immunodiffusion tests. Although antibodies specific for each organism could also be detected by immunodiffusion tests with high titre rabbit or bovine sera, these tests were insufficiently sensitive for routine diagnostic use. A quantitative Rose Bengal plate test, using Rose Bengal stained Br. abortus and Y. enterocolitica IX, was developed which enabled the antibody responses to the two organisms to be differentiated. The specificity of this test was confirmed by cross-absorption experiments and its sensitivity was sufficient to permit evaluation of all bovine sera giving positive reactions to the serum agglutination test. ImagesFig. 1Fig. 2 PMID:4992575

  3. Determination of O:4 antigen-antibody affinity level in O:5 antigen positive and negative variants of Salmonella enterica serovar Typhimurium.

    PubMed

    Nakai, Yuka; Ito, Akihisa; Ogawa, Yohsuke; Aribam, Swarmistha Devi; Elsheimer-Matulova, Marta; Shiraiwa, Kazumasa; Kisaka, Stevens M B; Hikono, Hirokazu; Nishikawa, Sayaka; Akiba, Masato; Kawahara, Kazuyoshi; Shimoji, Yoshihiro; Eguchi, Masahiro

    2017-04-01

    Salmonella enterica serovar Typhimurium (S. Typhimurium) has two serological variants: one that expresses the O:5 antigen (1,4,5,12:i:1,2) and one that lacks O:5 antigen (1,4,12:i:1,2). For serotyping, S. Typhimurium is agglutinated by diagnostic O:4 antigen serum. This study was carried out to compare the antigen-antibody affinity of O:4 antigen in S. Typhimurium χ3306 O:5-positive and S. Typhimurium χ3306 O:5-negative strains. The affinity of O:4 antigen with O:4 antigen serum was found to be stronger in the O:5-negative strains compared to O:5-positive strains. Next, we investigated the antigen-antibody affinity of O:4 antigen with O:4 antigen serum in field strains of S. Typhimurium, which showed the same tendency in affinity as seen with S. Typhimurium χ3306 O:5-positive and negative strains. This study suggests that the presence or absence of O:5 antigen causes differences in O:4 agglutination reactions with different field strains of S. Typhimurium. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Comparisons of Venezuelan encephalitis virus strains by hemagglutination-inhibition tests with chicken antibodies.

    PubMed Central

    Scherer, W F; Pancake, B A

    1977-01-01

    Twenty strains of Venezuelan encephalitis (VE) virus inoculated intravenously in large doses into roosters produced hemagglutination-inhibition (HI) antibodies detectable in plasmas within 7 to 10 days. No signs of illness occurred, and there was no evidence of viral growth in tissues since blood concentrations of infectious virus steadily decreased after inoculation. HI antibodies in early plasmas were specific for VE virus and did not cross-react significantly with two other North American alphaviruses, eastern and western encephalitis viruses. VE virus strains could be distinquished by virus-dilution, short-incubation HI, but not by plasma-dilution neutralization tests, by using early rooster antibodies. The distinctions by HI test were similar with some strains to, but different with other strains from, those described by Young and Johnson with the spiny rat antisera used to establish their subtype classifications of VE virus (14, 28). Nevertheless, results of HI tests with rooster antibodies correlated with equine virulence, as did results with spiny rat antibodies, and distinguished the new strains of virus that appeared in Middle America during the VE outbreak of 1969 from preexisting strains. PMID:591629

  5. ANTIBODY FORMATION IN WORKERS OF ROENTGEN DEPARTMENTS VACCINATED WITH LIVE TULAREMIA VACCINE (in Russian)

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

    Marder, B.B.

    1961-01-01

    Workers of roentgenological departments, physicians, roentgen technicians and auxiliary personnel (a totul of 15 persons) were immunized by the pericutaneous method with live tularemia vaccine. For comparison, subject to immunization were 5 medical workers not working in roentgenological departments. In all the persons immunized blood was taken 1, 2, 3 months and one year after the vaccination for studies of the agglutination titers of sera. The lowest antibody titer was seen in roentgen technicians, whereas the highest---in auxiliary personnel and the controls. (auth)

  6. Development of monoclonal antibodies bearing the internal image of the gizzerosine epitope and application in a competitive ELISA for fish meal.

    PubMed

    Manosalva, Headdy; De Ioannes, Alfredo E; Becker, María Inés

    2004-02-01

    Gizzerosine (GZ), a derivative of histamine, is a biogenic amine found in fish meal, and one of the causative agents of black vomit, a poultry disease. We describe here the preparation of anti-idiotype antibodies to the anti-GZ monoclonal antibody (anti-GZ 3H4) and their possible application to an immunoassay. BALB-c mice were immunized with anti-GZ 3H4 antibody coupled to hemocyanin from Concholepas concholepas. Using somatic cell fusion between NSO/2 cells and splenic lymphocytes from the immunized mice, we obtained 34 potential anti-idiotype antibodies. They were characterized by passive agglutination with supernatants from hybridoma cultures and latex particles conjugated to the idiotype. Anti-idiotype antibodies were analyzed by a competitive RIA, to determine their ability to dissociate the interaction between (125)I-GZ and the anti-GZ 3H4-idiotype antibody. They were also characterized by GZ inhibition of latex passive agglutination assay. Three anti-idiotypes named 2D11, 2H6, and 3A12, all of the IgG isotype, were obtained. They were evaluated by a competitive ELISA, in which GZ competes with the tracer (HRP-idiotype). All presented sensitivity in the range of 0.1-10 microg/mL of GZ; and the 3A12 anti-idiotype antibody showed the best performance. An ELISA was developed using the idiotype bound to the solid phase and the anti-idiotype 3A12-HRP as the tracer. The assay showed a similar sensitivity and cross-reactivity with histamine was only observed at concentrations over 10 microg/mL. Lysine and histidine did not interfere with the assay up to 500 microg/mL. An experiment was conducted with fish meal contaminated with synthetic GZ. The results are promising, and showed that no other compounds of the fish meal interfere with the ELISA system; however the extraction procedure of the sample needs to be improved. From the results presented here, we conclude that the idiotype anti-idiotype ELISA would be an appropriate method to determine GZ in fish meal.

  7. Presence of antigen and antibodies in serum and genital discharges of cows from dairy herds naturally infected with Leptospira interrogans serovar hardjo.

    PubMed

    Dhaliwal, G S; Murray, R D; Dobson, H; Montgomery, J; Ellis, W A

    1996-03-01

    Samples of cervico-vaginal mucus from 163 bulling cows (group 1) and post calving discharges from 59 newly calved cows (group 2) in five dairy herds naturally infected with Leptospira interrogans serovar hardjo were examined for the presence of antigen and IgG and IgA antibodies by using two ELISA systems which were protein or carbohydrate based. Corresponding serum samples were examined for systemic immune responses by using a microscopic agglutination test (MAT) and IgG-ELISA tests. Antigen was detected by direct immunofluorescence in six of the 163 samples of cervico-vaginal mucus. Both IgG and IgA antibodies were detected by ELISA in the genital discharges with a prevalence much higher than that obtained by the MAT but lower than that observed with the serum IgG-ELISA. Combining both groups, none of the MAT-positive cattle was negative by serum-ELISA. By using the protein or carbohydrate fraction serum IgG-ELISA assays, respectively, 29 or 41 per cent of the MAT-negative cows were positive at a titre of at least 1:40. Similarly, eight or 23 samples (10 or 27 per cent) had titres of at least 1:20 in the genital discharge ELISA for IgG and IgA antibodies, respectively. The serum IgG-ELISA was the most efficient in detecting hardjo antibodies, but in group 2 the IgG- and IgA-ELISA of the post calving discharge proved to be equally effective.

  8. Prevalence of Diego blood group antigen and the antibody in three ethnic population groups in Klang valley of Malaysia.

    PubMed

    Wei, Cheong Tar; Al-Hassan, Faisal Muti; Naim, Norris; Knight, Aishah; Joshi, Sanmukh R

    2013-01-01

    Diego blood group antigen, Di(a), is very rare among Caucasians and Blacks, but relatively common among the South American Indians and Asians of Mongolian origin. The antibody to Di(a) is clinically significant to cause hemolytic disease in a new-born or hemolytic transfusion reaction. This study was designed to determine the prevalence of Di(a) antigen among the blood donors from the three major ethnic groups in Klang Valley of Malaysia as well as to find an incidence of an antibody of the Diego antigen, anti-Di(a), in a tertiary care hospital to ascertain the need to include Di(a+) red cells for an antibody screen cell panel. Serological tests were performed by column agglutination technique using commercial reagents and following instruction as per kit insert. Di(a) antigen was found with a frequency of 2.1% among the Malaysians donors in three ethnic groups viz, Malay, Chinese and Indian. It was present among 1.25% of 401 Malay, 4.01% of Chinese and 0.88% of 114 Indian origin donors. None of the 1442 patients, including 703 antenatal outpatients, had anti-Di(a) in serum. The prevalence of Di(a) antigen was found among the donors of all the three ethnic background with varying frequency. Inclusion of Di(a+) red cells in routine antibody screening program would certainly help in detection of this clinically significant antibody and to provide safe blood transfusion in the Klang Valley, though the incidence of antibody appears to be very low in the region.

  9. Combined neutrophil and erythrocyte agglutination in a 7-year-old boy.

    PubMed

    Yenson, Paul R; Fleming, Adam; Kaikov, Yigal; Wadsworth, Louis D

    2007-09-01

    Leukoagglutination is a rare in vitro phenomenon, with demonstration of both temperature and/or ethylenediaminetetraacetic acid dependence. We report a case of combined leukocyte and erythrocyte agglutination in a 7-year-old male with Mycoplasma pneumoniae and Epstein-Barr virus coinfection. To our knowledge, this morphologic finding has not previously been described.

  10. Modification of the fluorescent antibody virus neutralisation test--elimination of the cytotoxic effect for the detection of rabies virus neutralising antibodies.

    PubMed

    Bedeković, Tomislav; Lemo, Nina; Lojkić, Ivana; Mihaljević, Zeljko; Jungić, Andreja; Cvetnić, Zeljko; Cač, Zeljko; Hostnik, Peter

    2013-04-01

    The virus neutralisation test is used for the quantitation of specific antibodies in serum samples. However, the success of the test depends on the quality of samples. In the case of poor quality samples, a cytotoxic effect can be observed and the results of the test can be compromised. Additionally, the cytotoxic effect limits the use of different substances, such as muscle extract or liquid from thoracic cavity (thoracic liquid), as a sample for the detection of rabies virus neutralising antibodies in the follow-up of fox oral vaccination campaigns. To eliminate the cytotoxic effect, a modified fluorescent antibody virus neutralisation (mFAVN) test was developed and evaluated. In the mFAVN test, inocula were removed after a 1h and the cytotoxic effect was prevented. According to the results obtained, the specificity of the mFAVN test compared to the FAVN test was 88.8% and the sensitivity was 94.4%. The diagnostic validity of the test was 0.99 (CI=0.98-1.00). To evaluate the possibility of using muscle extract and thoracic liquid as samples for the virus neutralisation test, 102 sera, muscle extract and thoracic liquid samples of dog origin were tested with the mFAVN test. The correlation between sera and muscle extracts was 87.9% (r=0.88, p<0.001). The correlation between sera and thoracic liquid was 94.2% (r=0.94, p<0.001). These findings indicated that both muscle extract and thoracic liquid could be used as samples for detection of rabies virus neutralising antibodies in the follow-up of oral vaccination campaigns. To evaluate the level of elimination of the cytotoxic effect, the 102 samples of sera, muscle extracts and thoracic liquid of dog origin were also tested in parallel using the mFAVN and FAVN tests. In the mFAVN test, no instance of cytotoxic effect was observed in the cells. In the FAVN test, two sera (1.9%), 35 muscle extracts (34.3%) and 56 thoracic liquid samples (54.9%) showed cytotoxic effect. The results of this study strongly suggest that

  11. Direct detection of methicillin resistance in Staphylococcus aureus in blood culture broth by use of a penicillin binding protein 2a latex agglutination test.

    PubMed

    Qian, Qinfang; Venkataraman, Lata; Kirby, James E; Gold, Howard S; Yamazumi, Toshiaki

    2010-04-01

    We studied the utility of performing a penicillin binding protein 2a latex agglutination (PBP-LA) assay directly on Bactec blood culture broth samples containing Staphylococcus aureus to rapidly detect methicillin resistance. The sensitivity, specificity, positive predictive value, and negative predictive value of this method were 94.1%, 97.5%, 98%, and 92.9%, respectively.

  12. Validation of a Microsphere Immunoassay for Serological Leptospirosis Diagnosis in Human Serum by Comparison to the Current Gold Standard

    PubMed Central

    Wynwood, Sarah J.; Burns, Mary-Anne A.; Graham, Glenn C.; Weier, Steven L.; McKay, David B.; Craig, Scott B.

    2015-01-01

    A microsphere immunoassay (MIA) utilising Luminex xMap technology that is capable of determining leptospirosis IgG and IgM independently was developed. The MIA was validated using 200 human samples submitted for routine leptospirosis serology testing. The traditional microscopic agglutination (MAT) method (now 100 years old) suffers from a significant range of technical problems including a dependence on antisera which is difficult to source and produce, false positive reactions due to auto-agglutination and an inability to differentiate between IgG and IgM antibodies. A comparative validation method of the MIA against the MAT was performed and used to determine the ability of the MIA to detect leptospiral antibodies when compared with the MAT. The assay was able to determine samples in the reactive, equivocal and non-reactive ranges when compared to the MAT and was able to differentiate leptospiral IgG antibodies from leptospiral IgM antibodies. The MIA is more sensitive than the MAT and in true infections was able to detect low levels of antibody in the later stages of the acute phase as well as detect higher levels of IgM antibody earlier in the immune phase of the infection. The relatively low cost, high throughput platform and significantly reduced dependency on large volumes of rabbit antisera make this assay worthy of consideration for any microbiological assay that currently uses agglutination assays. PMID:25807009

  13. Paper-based assay for red blood cell antigen typing by the indirect antiglobulin test.

    PubMed

    Yeow, Natasha; McLiesh, Heather; Guan, Liyun; Shen, Wei; Garnier, Gil

    2016-07-01

    A rapid and simple paper-based elution assay for red blood cell antigen typing by the indirect antiglobulin test (IAT) was established. This allows to type blood using IgG antibodies for the important blood groups in which IgM antibodies do not exist. Red blood cells incubated with IgG anti-D were washed with saline and spotted onto the paper assay pre-treated with anti-IgG. The blood spot was eluted with an elution buffer solution in a chromatography tank. Positive samples were identified by the agglutinated and fixed red blood cells on the original spotting area, while red blood cells from negative samples completely eluted away from the spot of origin. Optimum concentrations for both anti-IgG and anti-D were identified to eliminate the washing step after the incubation phase. Based on the no-washing procedure, the critical variables were investigated to establish the optimal conditions for the paper-based assay. Two hundred ten donor blood samples were tested in optimal conditions for the paper test with anti-D and anti-Kell. Positive and negative samples were clearly distinguished. This assay opens up new applications of the IAT on paper including antibody detection and blood donor-recipient crossmatching and extends its uses into non-blood typing applications with IgG antibody-based diagnostics. Graphical abstract A rapid and simple paper-based assay for red blood cell antigen typing by the indirect antiglobulin test.

  14. Competitive Enzyme-Linked Immunosorbent Assay for Detection of Leptospira interrogans Serovar pomona Antibodies in Bovine Sera

    PubMed Central

    Surujballi, Om; Mallory, Maria

    2001-01-01

    A competitive enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody (M898) was developed for detection of bovine antibodies to Leptospira interrogans serovar pomona. This assay was evaluated using field sera (n = 190) with serovar pomona microscopic agglutination test (MAT) titers of ≥100 as the positive population (group A); field sera (n = 1,445) which were negative in the MAT (1:100 dilution) for serovar pomona (group B); and sera (from a specific-pathogen-free cattle herd [n = 210]) which were negative in the MAT (1:100 dilution) for serovars canicola, copenhageni, grippotyphosa, hardjo, pomona, and sejroe (group C). At the cutoff point recommended by receiver operating characteristic (ROC) curve analysis of the combined ELISA results of serum groups A, B, and C, the sensitivity and specificity values were 93.7 and 96.3%, respectively. The value for the area under this ROC curve was 0.977, indicating a high level of accuracy for the ELISA. Similar results were obtained from the analysis of the combined results of serum groups A and B and from the analysis of the combined results of serum groups A and C. PMID:11139193

  15. Characterization of thyroid function and antithyroid antibody tests among Saudis

    PubMed Central

    Jammah, Anwar A.; Alshehri, Anwar S.; Alrakhis, Afaf A.; Alhedaithy, Asma S.; Almadhi, Asma M.; Alkwai, Hala M.; Alhamad, Maram M.; Alzahrani, Saad H.

    2015-01-01

    Objective: To determine the reference intervals for thyroid function tests and the prevalence of thyroid autoimmunity in the Saudi population. Methods: A cross-sectional prospective study was conducted in King Khalid University Hospital, Riyadh, Saudi Arabia from January to June 2013. History and physical examination were obtained. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were measured by Electro-chemiluminescence Immunoassay system-assay. Anti-thyroperoxidase, and anti-thyroglobulin antibodies were measured using enzyme-linked immunosorbent-assay. Subjects with previous or a family history of thyroid disorders, those taking medications affecting thyroid function, pregnant or lactating women, and those with goiter were excluded. Individuals with positive antibodies were excluded from the final analysis of the TSH reference range, but were used to determine the prevalence of thyroid autoimmunity. Results: Out of 337 Saudi subjects initially screened, 132 (aged 13-60 years) were candidates for reference calculation, the mean±standard deviation, and (2.5th-97.5th) percentile of TSH (mIU/L) was 1.96±0.9 (0.59-4.37), for FT4 (pmol/L) was 15.47±1.83 (12.04-19.13), and for FT3 (pmol/L) was 5.22±0.7 (4.07-6.76). The TSH was higher in the antibodies positive group (2.5±1.17 mIU/L) compared with the negative one (1.96±0.9 mIU/L) (p<0.05). Finally, 26% of subjects were tested positive for antithyroid antibodies. Conclusion: The TSH reference range was similar to laboratory references. Thyroid antibodies were prevalent in Saudis, necessitating further work in larger scale studies. PMID:25987111

  16. Characterization of thyroid function and antithyroid antibody tests among Saudis.

    PubMed

    Jammah, Anwar A; Alshehri, Anwar S; Alrakhis, Afaf A; Alhedaithy, Asma S; Almadhi, Asma M; Alkwai, Hala M; Alhamad, Maram M; Alzahrani, Saad H

    2015-06-01

    To determine the reference intervals for thyroid function tests and the prevalence of thyroid autoimmunity in the Saudi population.   A cross-sectional prospective study was conducted in King Khalid University Hospital, Riyadh, Saudi Arabia from January to June 2013. History and physical examination were obtained. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were measured by Electro-chemiluminescence Immunoassay system-assay. Anti-thyroperoxidase, and anti-thyroglobulin antibodies were measured using enzyme-linked immunosorbent-assay. Subjects with previous or a family history of thyroid disorders, those taking medications affecting thyroid function, pregnant or lactating women, and those with goiter were excluded. Individuals with positive antibodies were excluded from the final analysis of the TSH reference range, but were used to determine the prevalence of thyroid autoimmunity.   Out of 337 Saudi subjects initially screened, 132 (aged 13-60 years) were candidates for reference calculation, the mean±standard deviation, and (2.5th-97.5th) percentile of TSH (mIU/L) was 1.96±0.9 (0.59-4.37), for FT4 (pmol/L) was 15.47±1.83 (12.04-19.13), and for FT3 (pmol/L) was 5.22±0.7 (4.07-6.76). The TSH was higher in the antibodies positive group (2.5±1.17 mIU/L) compared with the negative one (1.96±0.9 mIU/L) (p less than 0.05). Finally, 26% of subjects were tested positive for antithyroid antibodies.   The TSH reference range was similar to laboratory references. Thyroid antibodies were prevalent in Saudis, necessitating further work in larger scale studies.

  17. Direct measurement of IgM-Antigen interaction energy on individual red blood cells.

    PubMed

    Yeow, Natasha; Tabor, Rico F; Garnier, Gil

    2017-07-01

    Most blood grouping tests rely on the principle of red blood cells (RBCs) agglutination. Agglutination is triggered by the binding of specific blood grouping antibodies to the corresponding RBC surface antigen on multiple cells. The interaction energies between blood grouping antibodies and antigens have been poorly defined in immunohaematology. Here for the first time, we functionalized atomic force microscope (AFM) cantilevers with the IgM form of blood grouping antibodies to probe populations of individual RBCs of different groups under physiological conditions. The force-mapping mode of AFM allowed us to measure specific antibody - antigen interactions, and simultaneously localize and quantify antigen sites on the scanned cell surface. This study provides a new insight of the interactions between IgM antibodies and its corresponding antigen. The technique and information can be translated to develop better blood typing diagnostics and optimize target-specific drug delivery for medical applications. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  18. 9 CFR 147.6 - Procedure for determining the status of flocks reacting to tests for Mycoplasma gallisepticum...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... agglutination test, enzyme-labeled immunosorbent assay (ELISA), official molecular examination procedure, or... the tube agglutination, ELISA, or serum plate test is positive, the hemaglutination inhibition (HI...

  19. 9 CFR 147.6 - Procedure for determining the status of flocks reacting to tests for Mycoplasma gallisepticum...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... agglutination test, enzyme-labeled immunosorbent assay (ELISA), official molecular examination procedure, or... the tube agglutination, ELISA, or serum plate test is positive, the hemaglutination inhibition (HI...

  20. 9 CFR 147.6 - Procedure for determining the status of flocks reacting to tests for Mycoplasma gallisepticum...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... agglutination test, enzyme-labeled immunosorbent assay (ELISA), official molecular examination procedure, or... the tube agglutination, ELISA, or serum plate test is positive, the hemaglutination inhibition (HI...

  1. Functionality of Immunoglobulin G and Immunoglobulin M Antibody Physisorbed on Cellulosic Films

    PubMed Central

    Huang, Ziwei; Raghuwanshi, Vikram Singh; Garnier, Gil

    2017-01-01

    The functionality and aging mechanism of antibodies physisorbed onto cellulosic films was investigated. Blood grouping antibodies immunoglobulin G (IgG) and immunoglobulin M (IgM) were adsorbed onto smooth cellulose acetate (CAF) and regenerated cellulose (RCF) films. Cellulose films and adsorbed IgG layers were characterized at the air and liquid interface by X-ray and neutron reflectivity (NR), respectively. Cellulose film 208 Å thick (in air) swell to 386 Å once equilibrated in water. IgG adsorbs from solution onto cellulose as a partial layer 62 Å thick. IgG and IgM antibodies were adsorbed onto cellulose and cellulose acetate films, air dried, and aged at room temperature for periods up to 20 days. Antibody functionality and surface hydrophobicity were measured everyday with the size of red blood cell (RBC) agglutinates (using RBC specific to IgG/IgM) and the water droplet contact angle, respectively. The functionality of the aged IgG/IgM decreases faster if physisorbed on cellulose than on cellulose acetate and correlates to surface hydrophobicity. IgG physisorbed on RCF or CAF age better and remain functional longer than physisorbed IgM. We found a correlation between antibody stability and hydrogen bond formation ability of the system, evaluated from antibody carbonyl concentration and cellulosic surface hydroxyl concentration. Antibody physisorbs on cellulose by weak dipole forces and hydrogen bonds. Strong hydrogen bonding contributes to the physisorption of antibody on cellulose into a non-functional configuration in which the molecule relaxes by rotation of hydophobic groups toward the air interface. PMID:28770196

  2. Lead isotopic studies of lunar soils - Their bearing on the time scale of agglutinate formation

    NASA Technical Reports Server (NTRS)

    Church, S. E.; Tilton, G. R.; Chen, J. H.

    1976-01-01

    Fines (smaller than 75 microns) and bulk soil were studied to analyze loss of volatile lead; losses of the order of 10% to 30% radiogenic lead during the production of agglutinates are assessed. Lead isotope data from fine-agglutinate pairs are analyzed for information on the time scale of micrometeorite bombardment, from the chords generated by the data in concordia diagrams. Resulting mean lead loss ages were compared to spallogenic gas exposure ages for all samples. Labile parentless radiogenic Pb residing preferentially on or in the fines is viewed as possibly responsible for aberrant lead loss ages. Bulk soils plot above the concordia curve (in a field of excess radiogenic Pb) for all samples with anomalous ages.

  3. Antibody detection tests improve the sensitivity of tuberculosis diagnosis in cattle.

    PubMed

    Casal, C; Infantes, J A; Risalde, M A; Díez-Guerrier, A; Domínguez, M; Moreno, I; Romero, B; de Juan, L; Sáez, J L; Juste, R; Gortázar, C; Domínguez, L; Bezos, J

    2017-06-01

    We evaluated the sensitivity (Se) of the single cervical intradermal tuberculin (SIT) test, two interferon-gamma (IFN-γ) assays and three different antibody detection techniques for bovine tuberculosis (bTB) diagnosis in 131 mixed beef breed cattle. The results of the diagnostic techniques performed over the whole herd, and over the animals confirmed as infected based on the presence of lesions compatible with the disease and/or M. bovis isolation were compared to determine apparent prevalence (AP) and Se. The Se of the SIT test (severe interpretation) was 63.7% (95% CI, 54.54-72.00), while the Se of the IFN-γ assays ranged between 60.2% and 92%. The proportion of infected cattle detected by the different antibody detection techniques ranged from 65.5% to 87.6%. Three of the antibody detection techniques yielded a significant higher (p<0.05) Se than that achieved with the official diagnostic techniques. In addition, the interpretation in parallel of cellular and antibody detection techniques reached the highest Se: 98.2% (95% CI, 93.78-99.51) suggesting that the use of diagnostic techniques detecting both cellular and humoral responses could be considered as an alternative in the control of bTB outbreaks in high prevalence settings. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Agglutinated foraminifera from the Ludlow (Silurian) of Ireland

    NASA Astrophysics Data System (ADS)

    Kaminski, Michael; Ferretti, Annalisa; Messori, Fabio; Papazzoni, Cesare Andrea; Sevastopulo, George

    2017-04-01

    Agglutinated foraminifera are one of the most primitive groups of foraminifera, possibly already appearing in the Cryogenian but usually rare in lower Paleozoic rocks. Their mean standing diversity slowly increased during Cambrian and Ordovician times, reaching a stable value of about 50 genera in the mid-Silurian which remained fairly constant up to the Triassic. An assemblage of agglutinated foraminifera was unexpectedly found in conodont residue from material collected in the Dingle Peninsula, County Kerry, southwestern Ireland. This material comes from rare calcareous occurrences in volcanoclastics previously known for their rich trilobite and conodont assemblages. The limestones are trilobite-crinoidal silty wackestone to packstone, with local brachiopod concentrations, documenting brachiopod-trilobite-crinoidal dominated communities of shallow and well-ventilated water that might have periodically colonized the bottom intercalating with volcanic events and then successively redeposited in deeper waters. The conodont fauna indicates an early Ludlow (Gorstian-earliest Ludfordian) age (Kaminski et al., 2016). The foraminiferal assemblage has limited potential for stratigraphical correlation as long-range taxa are present, but it represents the first record from the Silurian of Ireland. The assemblage is dominated by tubothalamids (Rectoammodiscus and rare Sansabaina), with less abundant monothalamids (Psammosiphonella and Psammosphaera). The assemblage displays low diversity compared with other assemblages described from the British Isles (Kircher & Brasier, 1989). At the species level, this assemblage is identical to those described previously from the Silurian of North America but with lower diversity. Only Rectoammodiscus diai had apparently a wider geographic distribution, including not only the central USA (Oklahoma and Kansas) but also the Welsh Borderlands and Senegal. The affinities with the assemblages reported at several localities in the central

  5. The influence of different techniques in characterizing human antibodies to cow's milk proteins

    PubMed Central

    McCaffery, T. D.; Kraft, S. C.; Rothberg, R. M.

    1972-01-01

    Sera from 760 subjects with and without inflammatory bowel disease (IBD) were studied selectively using both primary and secondary antibody assay techniques and different cow's milk antigens. Techniques which demonstrate antibody–antigen binding revealed that the incidence, amount and immunoglobulin class of detectable antibody to bovine serum albumin (BSA) were not significantly different among IBD and control subjects. Only 13 of the 138 sera with the most anti-BSA by primary binding techniques had the capacity to precipitate spontaneously either BSA or antigens in raw (RSM) and pasteurized (PSM) skimmed milk. In passive haemagglutination studies, 41% of these 138 sera had the capacity to agglutinate BSA-coated erythrocytes, while the respective figures for RSM and PSM were 56% and 77%. Only in studies employing the passive haemagglutination of RSM-coated erythrocytes were high titres found more frequently in sera from patients with IBD than in sera from control subjects. Taken as a whole, this study fails to provide evidence for the pathogenetic significance of milk antibodies in IBD. PMID:4625158

  6. [The mechanism of change in speed of agglutination of human erythrocytes under the influence of adrenaline].

    PubMed

    Volodchenko, A I; Tsirkin, V I; Kostiaev, A A

    2014-01-01

    In the study of red blood cells of 80 men found that adrenaline (10(-10) - 10(-6) g/mL) and phenylephrine (10-(10) - 10(-6) g/mL) dose-dependently increase the speed of agglutination of red blood cells, according to the decrease in agglutination of the start time and ginipral (10(-10) - 10(-7) g/mL), on the contrary, decreases it. The effect of adrenaline and phenylephrine is blocked by nicergoline (10(-6) g/mL), increased obzidan (10(-6) g/mL) and does not change under the action ofyohimbine (10(-6) g/mL) and atenolol (10(-6) g/mL). These data indicate that the speed of agglutination increases with activation alpha1-adrenergic receptor (AR) and decreases in the activation of beta2-AR, while the activation of alpha2- and beta1-AR does not affect it. Trifluoperazine (10(-6) g/mL) as the calmodulin antagonist, barium chloride (10(-6) g/mL) as a blocked of Ca(2+)-dependent K(+)-channels and indomethacine (10(-6) g/mL) as an inhibitor of cyclooxygenase and phospholipase A2 inhibit the ability of adrenaline to increases the speed of agglutination of red blood cells. This suggests that the effect of adrenaline caused an increase in erythrocyte entry of Ca2+, activation of calmodulin, cyclooxygenase, phospholipase A2 and the release of K+ from red blood cell through the Ca(2+)-dependent K+ channels, which is regarded as a manifestation of eryptosis. Indirectly, this means that more efficient activation of alpha1-AR and beta2-AR, respectively, increases or, conversely, decreases the rate of eryptosis.

  7. Effect of cutaneous and digestive colonization in the induction of anti-Candida albicans antibodies: experimental study.

    PubMed

    Nogueira, J M; Garcia-de-Lomas, J; Buesa, F J; Prat, J; Mir, A; Camarena, J J

    1985-10-01

    Candida albicans colonization induces antibodies, which must be taken into account in the serological diagnosis of candidiasis. In order to determine the degree of this effect, an experimental study in rabbits free of specific anti-Candida antibodies by cutaneous and digestive inoculation has been carried out. The evolution of humoral response was studied over 8 weeks by indirect immunofluorescence (IIF), direct agglutination (DA), counterimmunoelectrophoresis (CIE) and double diffusion (DD). The cutaneous colonization detectable by culture was maintained until the second week in 70% of the animals and the presence of antibodies detectable by IIF and DA was observed after the 2nd week. The highest antibody titre by IFF and DA was 1/64, and was reached in the 5th week, with a tendency to drop in the following weeks. Precipitins were only detected by CIE in 15% of the animals in the 7th week. Elimination of yeast in stools continued only in 20% of the animals in the 2nd week of the experiment. Antibodies were detected by IIF and DA after the 2nd week, with the highest titres detectable by IFF in the 5th week. Precipitant antibodies detectable by CIE appeared in 15% of the animals in the 8th week.

  8. Evaluation of IgY Antibody as a Polyspecific Coombs-Reagent

    PubMed Central

    Calzado, Esteban Justo Gutiérrez; Heredia, Marlene Toledano; Duharte, Jeorge Fernadez; Zarnani, Amir-Hassan

    2017-01-01

    Background: During the last twenty years, the extraction of specific egg yolk (IgY) antibodies from the immunized chickens has been accepted as a useful alternative to the immunization of mammals. The aim of the present study was immunizing the chickens with Human Umbilical Cord Serum (HUCS) and the extraction of specific anti-human globulins (IgG, C3b, and C3d) antibodies from egg yolk in order to obtain polyspecific Coombs reagent. Methods: The novelty of this work was the achievement of a polyclonal reagent through a very cheap alternative method in accordance with all ethical regulations required for obtaining it. Three Leghorn hens (21 weeks old) were immunized four times for a period of 66 days with 20uL of HUCS mixed with PBS/FCA or FIA each time. The extraction of IgY antibodies was performed according to the method of lipid precipitation of yolk and using water soluble fraction as the reagent material. The resulting IgY antibody was characterized by SDS-PAGE and immunoelectrophoresis and tested for the presence of hetero-agglutinins by means of direct agglutination using human erythrocytes of all blood groups treated with 0.1% papain and for indirect Coombs-test to evaluate its specificity to fractions (C3b, C3d, C4d) of human complement and human IgG, respectively. Results: Our findings show, that, the reagent obtained contains IgY and other 3 proteins (SDS-PAGE), and reacts specifically with plasma proteins, that migrate in β and ϒ regions. In immunoelectrophoresis, in addition, there is the presence of low hetero-agglutinins levels in IgY-preparation (3 lots), and the possibility to produce high amount (more than 500 ml/egg) of polyspecific Coombs-reagent in chickens is also discussed. Conclusion: IgY-preparation (3 lots), and the possibility to produce high amount (more than 500 ml/egg) of polyspecific Coombs-reagent in chickens with the originality to achieve a polyclonal reagent through a very cheap alternative method in accordance with all ethical

  9. An international study of agglutinins to Eubacterium, Peptostreptococcus and Coprococcus species in Crohn's disease, ulcerative colitis and control subjects.

    PubMed

    Wensinck, F; van de Merwe, J P; Mayberry, J F

    1983-01-01

    The world-wide occurrence of agglutinating antibodies to four coccoid anaerobes belonging to Eubacterium, Peptostreptococcus and Coprococcus spp. was investigated in 937 coded sera from patients suffering from Crohn's disease, ulcerative colitis, various other diseases and from healthy controls. Positive results were found in 59% of patients with Crohn's disease, 29% of patients with ulcerative colitis, and 8% of both diseased and healthy control subjects. Patients with Crohn's disease of the colon had more positive tests (67%) than patients with disease confined to the small bowel (46%). The results show that agglutinating antibodies to the coccoid anaerobes occur more frequently in patients with Crohn's disease than in other subjects in widely varying geographic regions.

  10. High-Throughput Incubation and Quantification of Agglutination Assays in a Microfluidic System.

    PubMed

    Castro, David; Conchouso, David; Kodzius, Rimantas; Arevalo, Arpys; Foulds, Ian G

    2018-06-04

    In this paper, we present a two-phase microfluidic system capable of incubating and quantifying microbead-based agglutination assays. The microfluidic system is based on a simple fabrication solution, which requires only laboratory tubing filled with carrier oil, driven by negative pressure using a syringe pump. We provide a user-friendly interface, in which a pipette is used to insert single droplets of a 1.25-µL volume into a system that is continuously running and therefore works entirely on demand without the need for stopping, resetting or washing the system. These assays are incubated by highly efficient passive mixing with a sample-to-answer time of 2.5 min, a 5⁻10-fold improvement over traditional agglutination assays. We study system parameters such as channel length, incubation time and flow speed to select optimal assay conditions, using the streptavidin-biotin interaction as a model analyte quantified using optical image processing. We then investigate the effect of changing the concentration of both analyte and microbead concentrations, with a minimum detection limit of 100 ng/mL. The system can be both low- and high-throughput, depending on the rate at which assays are inserted. In our experiments, we were able to easily produce throughputs of 360 assays per hour by simple manual pipetting, which could be increased even further by automation and parallelization. Agglutination assays are a versatile tool, capable of detecting an ever-growing catalog of infectious diseases, proteins and metabolites. A system such as this one is a step towards being able to produce high-throughput microfluidic diagnostic solutions with widespread adoption. The development of analytical techniques in the microfluidic format, such as the one presented in this work, is an important step in being able to continuously monitor the performance and microfluidic outputs of organ-on-chip devices.

  11. Sociodemographic and environmental analysis for the occurrence of anti-Leptospira antibodies in dogs of Teresina, Piauí, Brazil.

    PubMed

    Silva, Elís Rosélia Dutra de Freitas Siqueira; Castro, Vanessa; Mineiro, Ana Lys Bezerra Barradas; Prianti, Maria das Graças; Martins, Gustavo Henrique Chaves; Santana, Misael das Virgens; Brito, Lucas Moreira; Silva, Silvana Maria Medeiros de Sousa

    2018-05-01

    Leptospirosis is a worldwide zoonosis whose transmission is interlinked by multiple factors in the man-animal-ecosystem interface. This study aimed to evaluate the risk factors for the occurrence of anti-Leptospira antibodies in dogs in the capital Teresina (PI), and to determine their spatial distribution. Five hundred fifty-eight dog blood samples were submitted to the Microscopic Serum Agglutination (MSA) test. We applied semi-structured questionnaires to dog owners and obtained the area of residence for projection in geographical maps. Serum prevalence was 13.8%, in which the most common serovar was icterohaemorrhagiae, with 49.2%. Dogs with street access, failure to collect food bowl and low income of owners were risk factors. There was a higher number of seropositive dogs in the rainy season, with 87.1%, which is a probable risk factor for the occurrence of cases. The distribution of seropositive dogs was widely spread in the city, with predominance of cases in anthropized areas. These risk factors favor the occurrence of anti-Leptospira antibodies in dogs that are agent maintenance sources in the city and reinforce the need for epidemiological and environmental surveillance to prevent leptospirosis.

  12. Mumps prophylaxis in the light of a new test for antibody.

    PubMed Central

    Mortimer, P P

    1978-01-01

    A radial haemolysis test was used to investigate immunity to mumps. Antibody was found in 92 (42%) out of 220 children aged up to 5 years, 124 (78%) out of 159 children aged 6--10 years, 192 (86%) out of 222 children aged 11 years, 138 (92%) out of 150 children aged 15 years, and 280 (95%) out of 296 women attending an antenatal clinic. A group of 307 cadets aged 16--18 years were also tested and interviewed: 133 (95%) out of 140 who said that they had had mumps and 108 (87%) out of 124 who said that they had not had mumps were found to have antibody. The results suggest that tests for immunity to mumps by radial haemolysis would permit more rational use of mumps-specific immunoglobulin and attenuated mumps vaccine. PMID:365288

  13. An Integrin from Shrimp Litopenaeus vannamei Mediated Microbial Agglutination and Cell Proliferation

    PubMed Central

    Zhang, Ying; Wang, Leilei; Wang, Lingling; Wu, Ning; Zhou, Zhi; Song, Linsheng

    2012-01-01

    Background Integrins are a family of adhesion receptors which regulate cell proliferation, differentiation, leukocyte migration, and complement receptor-dependent phagocytosis. In invertebrates, as a cell adhesion receptor, β integrins play an important role for the balanced activation of immune defense responses especially during the encounter of infections. The present study attempts to characterize the immune functions of shrimp integrin (LvIntegrin) to have better understanding on the immune system and its regulation mechanisms in shrimps. Methodology A shrimp integrin was identified from the Pacific white shrimp Litopenaeus vannamei (designated as LvIntegrin). Its full-length cDNA was of 2621 bp with an open reading frame (ORF) of 2439 bp encoding a polypeptide of 812 amino acids. The mRNA expression of LvIntegrin was significantly up-regulated at 3, 6 and 12 h after Listonella anguillarum challenge. The cDNA fragment encoding β integrin domains (βA and hybrid domain) of LvIntegrin was recombined and expressed in Escherichia coli BL21(DE3)-pLysS. The recombinant protein (rLvIntegrin) could significantly agglutinate the tested microbe including E. coli JM109, L. anguillarum, Micrococcus luteus and Candida dattiladattila in the presence of divalent cations. Moreover, when NIH3T3 cells were cultured with rLvIntegrin, the proliferation rate increased significantly in a dose-dependent manner. Conclusions LvIntegrin, a shrimp β integrin was identified from L. vannamei, shared several highly conserved features. LvIntegrin exhibited broad-spectrum agglutination activity towards both bacteria and fungi and could improve the proliferation of NIH3T3 cells, indicating that LvIntegrin is involved in the immune response against microbe challenge and regulation of cell proliferation as a cell adhesion receptor in shrimp. PMID:22792387

  14. An integrin from shrimp Litopenaeus vannamei mediated microbial agglutination and cell proliferation.

    PubMed

    Zhang, Ying; Wang, Leilei; Wang, Lingling; Wu, Ning; Zhou, Zhi; Song, Linsheng

    2012-01-01

    Integrins are a family of adhesion receptors which regulate cell proliferation, differentiation, leukocyte migration, and complement receptor-dependent phagocytosis. In invertebrates, as a cell adhesion receptor, β integrins play an important role for the balanced activation of immune defense responses especially during the encounter of infections. The present study attempts to characterize the immune functions of shrimp integrin (LvIntegrin) to have better understanding on the immune system and its regulation mechanisms in shrimps. A shrimp integrin was identified from the Pacific white shrimp Litopenaeus vannamei (designated as LvIntegrin). Its full-length cDNA was of 2621 bp with an open reading frame (ORF) of 2439 bp encoding a polypeptide of 812 amino acids. The mRNA expression of LvIntegrin was significantly up-regulated at 3, 6 and 12 h after Listonella anguillarum challenge. The cDNA fragment encoding β integrin domains (βA and hybrid domain) of LvIntegrin was recombined and expressed in Escherichia coli BL21(DE3)-pLysS. The recombinant protein (rLvIntegrin) could significantly agglutinate the tested microbe including E. coli JM109, L. anguillarum, Micrococcus luteus and Candida dattiladattila in the presence of divalent cations. Moreover, when NIH3T3 cells were cultured with rLvIntegrin, the proliferation rate increased significantly in a dose-dependent manner. LvIntegrin, a shrimp β integrin was identified from L. vannamei, shared several highly conserved features. LvIntegrin exhibited broad-spectrum agglutination activity towards both bacteria and fungi and could improve the proliferation of NIH3T3 cells, indicating that LvIntegrin is involved in the immune response against microbe challenge and regulation of cell proliferation as a cell adhesion receptor in shrimp.

  15. Role of enzyme-treated cells in RBC antibody screening using the gel test: a study of anti-RH1, -RH2, and -RH3 antibodies.

    PubMed

    Conne, Jocelyne; Schneider, Philippe; Tissot, Jean-Daniel

    2007-01-01

    The role of enzyme-treated cells (ETCs) in red blood cell (RBC) antibody screening has been the subject of controversy, and its place in the clinical routine remains to be determined. In this work, plasma samples containing anti-RH1 (anti-D; N = 10), anti-RH2 (anti-C; N = 10), or anti-RH3 (anti-E; N = 10) antibodies were studied. The samples were diluted in nonbuffered or buffered normal saline, as well as in a pool of AB plasma samples. Titers and scores were determined by means of the gel test, using the indirect antiglobulin test (IAT) as well as ETCs, with R(0)r, r'r, or r''r test cells. Our results showed that compared to the IAT, ETCs allowed a clearer detection of anti-RH2 and anti-RH3, but not of anti-RH1 antibodies. Based on our study, it is not clear whether the ETC phase of the gel test should be maintained for RBC antibody screening. 2007 Wiley-Liss, Inc.

  16. [Comparison of eight screening tests for ant-HCV antibody].

    PubMed

    Deguchi, Matsuo; Kagita, Masanori; Yamashita, Naoko; Nakano, Takasi; Tahara, Kazuko; Asari, Seishi; Iwatani, Yoshinori

    2002-09-01

    We compared eight HCV screening tests for detection of anti-HCV antibody; Ortho Quick Chaser HCV Ab (QC), Ortho HCV Ab ELISA III (ELISA), Ortho HVC Ab PA test III (PA), Lumipulse II Ortho HCV (LUMI), IMx HCV.DAINAPACKII (IMx), ARCHITECT HCV (ARCH), Immucheck.F-HCV C50 Ab (Immu), RANREAM HCV Ab Ex II (RAN). Sera from six hundred patients were examined by these eight screening tests. The positive rates of the eight screening tests were from 9.0% to 13.2%. Forty-five sera showed discrepant results between the eight screening tests, and about half of them showed weak positive reaction and/or false positive. Twenty-five of the forty-five sera were negative for ant-HCV antibody in the CHIRON RIBA III confirmatory test, and forty-four of them were negative for HCV-RNA in the PCR method. The agreement rates between the two reagents were from 95.5% to 99.2%, but were not always high between the two reagents that used similar antigen. The specificities and sensitivities evaluated by using the RIBA III confirmatory test were excellent in ELISA, LUMI, IMx, ARCH and Immu. Three BBI seroconversion panels were used to compare the positive readings in the initial stage of HCV infection by eight screening tests. ELISA and ARCH showed the earliest positive readings, and then IMx, LUMI = RAN, PA, QC and Immu in this order. These findings indicate that ELISA and ARCH were the most excellent in the sensitivity, specificity and early diagnosis of HCV infection. However, we must pay attention to the weak positive reaction in the screening tests, because there is a possibility of "false positive".

  17. Comparison of two commercial rapid in-clinic serological tests for detection of antibodies against Leishmania spp. in dogs.

    PubMed

    Athanasiou, Labrini V; Petanides, Theodoros A; Chatzis, Manolis K; Kasabalis, Dimitrios; Apostolidis, Kosmas N; Saridomichelakis, Manolis N

    2014-03-01

    Antibodies against Leishmania spp. are detected in most dogs with clinical signs of leishmaniasis due to Leishmania infantum. Accurate, rapid in-clinic serological tests may permit immediate confirmation of the diagnosis and implementation of therapeutic measures. The aim of the current study was to evaluate the diagnostic accuracy of 2 commercial, rapid in-clinic serological tests for the detection of anti-Leishmania antibodies in sera of dogs, the Snap Canine Leishmania Antibody Test kit (IDEXX Laboratories Inc., Westbrook, Maine) and the ImmunoRun Antibody Detection kit (Biogal Galed Labs, Kibbutz Galed, Israel), using indirect fluorescent antibody test (IFAT) as the reference method. A total of 109 sera collected from 65 seropositive and 44 seronegative dogs were used. The sensitivities of the Snap and ImmunoRun kits were 89.23% (95% confidence interval: 79.05-95.54%) and 86.15% (95% confidence interval: 75.33-93.45%), respectively, and the specificity of both tests was 100%. A good agreement between each of the rapid in-clinic serological tests and IFAT and between the 2 rapid in-clinic serological tests was witnessed. Both rapid in-clinic serological tests showed an adequate diagnostic accuracy and can be used for the fast detection of antibodies against L. infantum in dogs.

  18. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test... serum. The measurements aid in the diagnosis of chronic hepatitis (inflammation of the liver) and autoimmune connective tissue diseases (diseases resulting from antibodies produced against the body's own...

  19. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test... serum. The measurements aid in the diagnosis of chronic hepatitis (inflammation of the liver) and autoimmune connective tissue diseases (diseases resulting from antibodies produced against the body's own...

  20. 21 CFR 866.5120 - Antismooth muscle antibody immunological test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Immunological Test... serum. The measurements aid in the diagnosis of chronic hepatitis (inflammation of the liver) and autoimmune connective tissue diseases (diseases resulting from antibodies produced against the body's own...

  1. Serological tests for detecting Rift Valley fever viral antibodies in sheep from the Nile Delta.

    PubMed Central

    Scott, R M; Feinsod, F M; Allam, I H; Ksiazek, T G; Peters, C J; Botros, B A; Darwish, M A

    1986-01-01

    To determine the accuracy of serological methods in detecting Rift Valley fever (RVF) viral antibodies, we examined serum samples obtained from 418 sheep in the Nile Delta by using five tests. The plaque reduction neutralization test (PRNT) was considered the standard serological method against which the four other tests were compared. Twenty-four serum samples had RVF viral antibodies detected by PRNT. Hemagglutination inhibition and enzyme-linked immunosorbent assay antibodies to RVF virus were also present in the same 24 serum samples. Indirect immunofluorescence was less sensitive in comparison with PRNT, and complement fixation was the least sensitive. These results extend observations made with laboratory animals to a large field-collected group of Egyptian sheep. PMID:3533977

  2. Screening test for neutralizing antibodies against yellow fever virus, based on a flavivirus pseudotype.

    PubMed

    Mercier-Delarue, Séverine; Durier, Christine; Colin de Verdière, Nathalie; Poveda, Jean-Dominique; Meiffrédy, Vincent; Fernandez Garcia, Maria Dolores; Lastère, Stéphane; Césaire, Raymond; Manuggera, Jean-Claude; Molina, Jean-Michel; Amara, Ali; Simon, François

    2017-01-01

    Given the possibility of yellow fever virus reintroduction in epidemiologically receptive geographic areas, the risk of vaccine supply disruption is a serious issue. New strategies to reduce the doses of injected vaccines should be evaluated very carefully in terms of immunogenicity. The plaque reduction test for the determination of neutralizing antibodies (PRNT) is particularly time-consuming and requires the use of a confinement laboratory. We have developed a new test based on the use of a non-infectious pseudovirus (WN/YF17D). The presence of a reporter gene allows sensitive determination of neutralizing antibodies by flow cytometry. This WN/YF17D test was as sensitive as PRNT for the follow-up of yellow fever vaccinees. Both tests lacked specificity with sera from patients hospitalized for acute Dengue virus infection. Conversely, both assays were strictly negative in adults never exposed to flavivirus infection or vaccination, and in patients sampled some time after acute Dengue infection. This WN/YF17D test will be particularly useful for large epidemiological studies and for screening for neutralizing antibodies against yellow fever virus.

  3. Prevalence and genetic characterization of Toxoplasma gondii in free-range chickens from grocery stores and farms

    USDA-ARS?s Scientific Manuscript database

    Chickens are considered important in the epidemiology of Toxoplasma gondii. Chicken hearts (n=1185) obtained from the local markets were tested for T. gondii infection. Antibodies to T. gondii were assayed in fluid removed from the heart cavity using the modified agglutination test (MAT) at 1:5, 1:2...

  4. Isolation and genetic characterization of Toxoplasma gondii from the gray wolf Canis lupus

    USDA-ARS?s Scientific Manuscript database

    Little is known of the genetic diversity of Toxoplasma gondii circulating in wildlife. In the present study feral gray wolf (Canis lupus) from Minnesota were examined for T. gondii infection. Antibodies to T. gondii were detected in 130 (52.4%) of 248 wolves tested by the modified agglutination test...

  5. Comparison between available serologic tests for detecting antibodies against Anaplasma phagocytophilum and Borrelia burgdorferi in horses in Canada.

    PubMed

    Schvartz, Gili; Epp, Tasha; Burgess, Hilary J; Chilton, Neil B; Lohmann, Katharina L

    2015-07-01

    To investigate the agreement between available serologic tests for the detection of antibodies against Anaplasma phagocytophilum and Borrelia burgdorferi, 50 serum samples from horses of unknown clinical status and at low risk for infection were tested. In addition to a point-of-care enzyme-linked immunosorbent assay (pocELISA), the evaluated tests included 2 indirect fluorescent antibody tests (IFATs) for antibodies against A. phagocytophilum and an IFAT, an ELISA confirmed with Western blot, and the Lyme multiplex assay for antibodies against B. burgdorferi. For each pair-wise comparison between serologic tests, the difference in the proportion of seropositive results as well as kappa and the prevalence-adjusted, bias-adjusted kappa were calculated. The proportion of seropositive results differed significantly in each pairwise comparison of tests for detection of antibodies against A. phagocytophilum, and between the pocELISA and IFAT as well as between the pocELISA and Lyme multiplex assay for detection of antibodies against B. burgdorferi. Agreement based on kappa varied from poor to fair while agreement was improved when evaluating prevalence-adjusted, bias-adjusted kappa. Lack of agreement may be explained by differences in methodology between the evaluated tests, cross-reactivity or false-positive and false-negative tests. In addition to the limitations of serologic test interpretation in the absence of clinical disease, this data suggest that screening of horses for exposure to tick-borne diseases in nonendemic areas may not be warranted. © 2015 The Author(s).

  6. Restriction-Site-Specific PCR as a Rapid Test To Detect Enterohemorrhagic Escherichia coli O157:H7 Strains in Environmental Samples

    PubMed Central

    Kimura, Richard; Mandrell, Robert E.; Galland, John C.; Hyatt, Doreene; Riley, Lee W.

    2000-01-01

    Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is an important food-borne pathogen in industrialized countries. We developed a rapid and simple test for detecting E. coli O157:H7 using a method based on restriction site polymorphisms. Restriction-site-specific PCR (RSS-PCR) involves the amplification of DNA fragments using primers based on specific restriction enzyme recognition sequences, without the use of endonucleases, to generate a set of amplicons that yield “fingerprint” patterns when resolved electrophoretically on an agarose gel. The method was evaluated in a blinded study of E. coli isolates obtained from environmental samples collected at beef cattle feedyards. The 54 isolates were all initially identified by a commonly used polyclonal antibody test as belonging to O157:H7 serotype. They were retested by anti-O157 and anti-H7 monoclonal antibody enzyme-linked immunosorbent assay (ELISA). The RSS-PCR method identified all 28 isolates that were shown to be E. coli O157:H7 by the monoclonal antibody ELISA as belonging to the O157:H7 serotype. Of the remaining 26 ELISA-confirmed non-O157:H7 strains, the method classified 25 strains as non-O157:H7. The specificity of the RSS-PCR results correlated better with the monoclonal antibody ELISA than with the polyclonal antibody latex agglutination tests. The RSS-PCR method may be a useful test to distinguish E. coli O157:H7 from a large number of E. coli isolates from environmental samples. PMID:10831431

  7. Submicron polymer particles containing fluorescent semiconductor nanocrystals CdSe/ZnS for bioassays.

    PubMed

    Generalova, Alla N; Sizova, Svetlana V; Zdobnova, Tatiana A; Zarifullina, Margarita M; Artemyev, Michail V; Baranov, Alexander V; Oleinikov, Vladimir A; Zubov, Vitaly P; Deyev, Sergey M

    2011-02-01

    This study aimed to design a panel of uniform particulate biochemical reagents and to test them in specific bioassays. These reagents are polymer particles of different sizes doped with semiconductor nanocrystals and conjugated with either full-size antibodies or recombinant mini-antibodies (4D5 scFv fragment) designed by genetic engineering approaches. A panel of highly fluorescent polymer particles (150-800 nm) were formed by embedding CdSe/ZnS nanocrystals (quantum dots) into preformed polyacrolein and poly(acrolein-co-styrene) particles. Morphology, content and fluorescence characteristics of the prepared materials were studied by laser correlation spectroscopy, spectrophotometry, optical and fluorescent microscopy and fluorimetry. The obtained fluorescent particles sensitized by anti-Yersinia pestis antibodies were used for rapid agglutination glass test suitable for screening analysis of Y. pestis antigen and for microtiter particle agglutination, which, owing to its speed and simplicity, is very beneficial for diagnostic detection of Y. pestis antigen. Recombinant 4D5 scFv antibodies designed and conjugated with polymer particles containing quantum dots provide multipoint highly specific binding with cancer marker HER2/neu on the surface of SKOV-3 cell.

  8. [Detection of leptospira by culture of vitreous humor and detection of antibodies against leptospira in vitreous humor and serum of 225 horses with equine recurrent uveitis].

    PubMed

    Dorrego-Keiter, Elisa; Tóth, József; Dikker, Lieke; Sielhorst, Jutta; Schusser, Gerald Fritz

    2016-01-01

    In the ongoing discussion regarding the aetiopathogenesis of equine recurrent uveitis (ERU) it was the aim of the present study to elucidate the relationship of leptospira infection and ERU. In a population of 225 horses leptospira were examined in vitreous humor by culture and leptospira antibody were detected in vitreous humor and serum samples. Preoperative serum samples were collected from 221/225 ERU patients of different age, gender and breed. Undiluted vitreous humor was aseptically taken from 198/225 patients that underwent pars plana vitrectomy at the beginning of surgery and from 27/225 patients' eyeball after enucleation: Serum and vitreous humor were tested for specific leptospiral antibodies by microscopic agglutination test (MAT). Furthermore, vitreous humor was examined by culture. 20 patients which were euthanized due to a live-threatening disease other than ERU served as a control group. A total of 127/221 (57.5%) horses had serum antibodies (≥ 1:100). Most frequently antibodies against L. interrogans serovar Grippotyphosa were detected (79/127), followed by L. interrogans serovar lcterohaemorrhagiae (34/127) and L. interrogans serovar Bratislava (29/127). Only 79/225 horses (35.1%) had leptospiral antibodies in vitreous humor, in which L. interrogans serovar Grippotyphosa (67/79) was identified most frequently followed by L. interrogans serovar Pomona (18/79) and L. interrogans serovar lcterohaemorrhagiae (8/79) which was identified as single or multiple reaction. Isolation of leptospira from vitreous humor was positive in 34/212 horses (16%). 10/20 control horses had a positive antibody titer against leptospira in serum and 2/20 horses in vitreous humor, whereas there was no leptospira detected in culture. The result of 84% negative cultures from vitreous humor of 212 ERU patients is decisive for the diagnosis and therapy of ERU.

  9. Performance of an automated solid-phase red cell adherence system compared with that of a manual gel microcolumn assay for the identification of antibodies eluted from red blood cells.

    PubMed

    Finck, R H; Davis, R J; Teng, S; Goldfinger, D; Ziman, A F; Lu, Q; Yuan, S

    2011-01-01

    IgG antibodies coating red blood cells (RBCs) can be removed by elution procedures and their specificity determined by antibody identification studies. Although such testing is traditionally performed using the tube agglutination assay, prior studies have shown that the gel microcolumn (GMC) assay may also be used with comparable results. The purpose of this study was to compare an automated solid-phase red cell adherence (SPRCA) system with a GMC assay for the detection of antibodies eluted from RBCs. Acid eluates from 51 peripheral blood (PB) and 7 cord blood (CB) samples were evaluated by both an automated SPRCA instrument and a manual GMC assay. The concordance rate between the two systems for peripheral RBC samples was 88.2 percent (45 of 51), including cases with alloantibodies (n = 8), warm autoantibodies (n = 12), antibodies with no identifiable specificity (n = 2), and negative results (n = 23). There were six discordant cases, of which four had alloantibodies (including anti-Jka, -E, and -e) demonstrable by the SPRCA system only. In the remaining 2 cases, anti-Fya and antibodies with no identifiable specificity were demonstrable by the GMC assay only. All seven CB specimens produced concordant results, showing anti-A (n = 3), -B (n = 1), maternal anti-Jka (n = 2), or a negative result (n = 1). Automated SPRCA technology has a performance that is comparable with that of a manual GMC assay for identifying antibodies eluted from PB and CB RBCs.

  10. Comparison of four commercially available avidity tests for Toxoplasma gondii-specific IgG antibodies.

    PubMed

    Villard, O; Breit, L; Cimon, B; Franck, J; Fricker-Hidalgo, H; Godineau, N; Houze, S; Paris, L; Pelloux, H; Villena, I; Candolfi, E

    2013-02-01

    Toxoplasma infection in pregnant women may cause congenital toxoplasmosis. Diagnosis of infection is based on serological tests aimed at detecting IgM and IgG antibodies against Toxoplasma gondii. However, IgM antibodies are not an accurate marker for discriminating between acute and latent infection. Detection of residual or persistent IgM may occur months or even years after primary infection, while the IgG avidity test is a rapid means of identifying latent infections in pregnant women who exhibit both IgG and IgM anti-Toxoplasma antibodies on initial testing during pregnancy. In this study, we assessed and compared the performances of four commercially available Toxoplasma IgG avidity tests in immunocompetent and immunocompromised patients with acute and latent toxoplasmosis. The positive predictive value of high avidity to confirm latent toxoplasmosis was 100% for all the assays, indicating that high avidity is a hallmark of latent infection. However, the negative predictive value of high avidity ranged from 99.2% (bioMérieux) to 95.3% (Abbott), indicating that acute toxoplasmosis could not be reliably diagnosed based on low IgG avidity alone. Thus, the avidity test provides a rapid means for identifying latent Toxoplasma infection in immunocompetent pregnant women presenting both IgG and IgM anti-Toxoplasma antibodies on initial testing. In terms of cost-effectiveness, avidity testing is a powerful tool that optimizes screening and follow-up of pregnant women while minimizing the costs of screening by avoiding subsequent costly maternal and fetal investigation and unnecessary treatment. The cheapest assay, Vidas Toxo IgG Avidity, also had the best performance for the diagnosis of latent toxoplasmosis.

  11. Comparison of Four Commercially Available Avidity Tests for Toxoplasma gondii-Specific IgG Antibodies

    PubMed Central

    Breit, L.; Cimon, B.; Franck, J.; Fricker-Hidalgo, H.; Godineau, N.; Houze, S.; Paris, L.; Pelloux, H.; Villena, I.

    2013-01-01

    Toxoplasma infection in pregnant women may cause congenital toxoplasmosis. Diagnosis of infection is based on serological tests aimed at detecting IgM and IgG antibodies against Toxoplasma gondii. However, IgM antibodies are not an accurate marker for discriminating between acute and latent infection. Detection of residual or persistent IgM may occur months or even years after primary infection, while the IgG avidity test is a rapid means of identifying latent infections in pregnant women who exhibit both IgG and IgM anti-Toxoplasma antibodies on initial testing during pregnancy. In this study, we assessed and compared the performances of four commercially available Toxoplasma IgG avidity tests in immunocompetent and immunocompromised patients with acute and latent toxoplasmosis. The positive predictive value of high avidity to confirm latent toxoplasmosis was 100% for all the assays, indicating that high avidity is a hallmark of latent infection. However, the negative predictive value of high avidity ranged from 99.2% (bioMérieux) to 95.3% (Abbott), indicating that acute toxoplasmosis could not be reliably diagnosed based on low IgG avidity alone. Thus, the avidity test provides a rapid means for identifying latent Toxoplasma infection in immunocompetent pregnant women presenting both IgG and IgM anti-Toxoplasma antibodies on initial testing. In terms of cost-effectiveness, avidity testing is a powerful tool that optimizes screening and follow-up of pregnant women while minimizing the costs of screening by avoiding subsequent costly maternal and fetal investigation and unnecessary treatment. The cheapest assay, Vidas Toxo IgG Avidity, also had the best performance for the diagnosis of latent toxoplasmosis. PMID:23239801

  12. Nanoscale Mineralogy and Composition of Experimental Regolith Agglutinates Produced under Asteroidal Impact Conditions

    NASA Technical Reports Server (NTRS)

    Christoffersen, Roy; Cintala, M. J.; Keller, L. P.; See, T. H.; Horz, F.

    2013-01-01

    On the Moon, the energetics of smaller impactors and the physical/chemical characteristics of the granular regolith target combine to form a key product of lunar space weathering: chemically reduced shock melts containing optically-active nanophase Fe metal grains (npFe0) [1]. In addition to forming the optically dark glassy matrix phase in lunar agglutinitic soil particles [1], these shock melts are becoming increasingly recognized for their contribution to optically active patina coatings on a wide range of exposed rock and grain surfaces in the lunar regolith [2]. In applying the lessons of lunar space weathering to asteroids, the potential similarities and differences in regolith-hosted shock melts on the Moon compared to those on asteroids has become a topic of increasing interest [3,4]. In a series of impact experiments performed at velocities applicable to the asteroid belt [5], Horz et al. [6] and See and Horz [7] have previously shown that repeated impacts into a gabbroic regolith analog target can produce melt-welded grain aggregates morphologically very similar to lunar agglutinates [6,7]. Although these agglutinate-like particles were extensively analyzed by electron microprobe and scanning electron microscopy (SEM) as part of the original study [7], a microstructural and compositional comparison of these aggregates to lunar soil agglutinates at sub-micron scales has yet to be made. To close this gap, we characterized a representative set of these aggregates using a JEOL 7600 field-emission scanning electron microscope (FE-SEM), and JEOL 2500SE field-emission scanning transmission electron microscope (FE-STEM) both optimized for energy dispersive X-ray spectroscopy (EDX) compositional spectrum imaging at respective analytical spatial resolutions of 0.5 to 1 micron, and 2 to 4 nm.

  13. On a grain of sand - a microhabitat for the opportunistic agglutinated foraminifera Hemisphaerammina apta n. sp., from the early Eocene Arctic Ocean

    NASA Astrophysics Data System (ADS)

    McNeil, David H.; Neville, Lisa A.

    2018-02-01

    Hemisphaerammina apta n. sp. is an attached monothalamous agglutinated foraminifera discovered in shelf sediments of the early Eocene Arctic Ocean. It is a simple yet distinctive component of the endemic agglutinated foraminiferal assemblage that colonized the Arctic Ocean after the microfaunal turnover caused by the Paleocene-Eocene Thermal Maximum. Associated foraminifera are characterized by a high percentage of monothalamous species (up to 60 %) and are entirely agglutinated indicating a brackish (mesohaline) early Eocene Arctic Ocean. Hemisphaerammina apta occurs exclusively as individuals attached to fine detrital grains (0.2 to 1.8 mm) of sediment. It is a small species (0.06 to 0.2 mm in diameter), fine-grained, with a low hemispherical profile, no floor across the attachment area, no substantive marginal flange, no internal structures, and no aperture. Lacking an aperture, it apparently propagated and fed through minute (micrometre-sized) interstitial pores in the test wall. Attachment surfaces vary from concave to convex and rough to smooth. Grains for attachment are diverse in shape and type but are predominantly of quartz and chert. The presence of H. apta in the early Eocene was an opportunistic response to an environment with an active hydrological system (storm events). Attachment to grains of sand would provide a more stable base on a sea floor winnowed by storm-generated currents. Active transport is indicated by the relative abundance of reworked foraminifera mixed with in situ species. Contemporaneous reworking and colonization by H. apta is suggested by its attachment to a reworked specimen of Cretaceous foraminifera.

  14. Inadequacy of IgM antibody tests for diagnosis of Rocky Mountain Spotted Fever.

    PubMed

    McQuiston, Jennifer H; Wiedeman, Caleb; Singleton, Joseph; Carpenter, L Rand; McElroy, Kristina; Mosites, Emily; Chung, Ida; Kato, Cecilia; Morris, Kevin; Moncayo, Abelardo C; Porter, Susan; Dunn, John

    2014-10-01

    Among 13 suspected Rocky Mountain spotted fever (RMSF) cases identified through an enhanced surveillance program in Tennessee, antibodies to Rickettsia rickettsii were detected in 10 (77%) patients using a standard indirect immunofluorescent antibody (IFA) assay. Immunoglobulin M (IgM) antibodies were observed for 6 of 13 patients (46%) without a corresponding development of IgG, and for 3 of 10 patients (30%) at least 1 year post-onset. However, recent infection with a spotted fever group rickettsiae could not be confirmed for any patient, based on a lack of rising antibody titers in properly timed acute and convalescent serologic specimens, and negative findings by polymerase chain reaction testing. Case definitions used in national surveillance programs lack specificity and may capture cases that do not represent current rickettsial infections. Use of IgM antibodies should be reconsidered as a basis for diagnosis and public health reporting of RMSF and other spotted fever group rickettsiae in the United States. © The American Society of Tropical Medicine and Hygiene.

  15. Inadequacy of IgM Antibody Tests for Diagnosis of Rocky Mountain Spotted Fever

    PubMed Central

    McQuiston, Jennifer H.; Wiedeman, Caleb; Singleton, Joseph; Carpenter, L. Rand; McElroy, Kristina; Mosites, Emily; Chung, Ida; Kato, Cecilia; Morris, Kevin; Moncayo, Abelardo C.; Porter, Susan; Dunn, John

    2014-01-01

    Among 13 suspected Rocky Mountain spotted fever (RMSF) cases identified through an enhanced surveillance program in Tennessee, antibodies to Rickettsia rickettsii were detected in 10 (77%) patients using a standard indirect immunofluorescent antibody (IFA) assay. Immunoglobulin M (IgM) antibodies were observed for 6 of 13 patients (46%) without a corresponding development of IgG, and for 3 of 10 patients (30%) at least 1 year post-onset. However, recent infection with a spotted fever group rickettsiae could not be confirmed for any patient, based on a lack of rising antibody titers in properly timed acute and convalescent serologic specimens, and negative findings by polymerase chain reaction testing. Case definitions used in national surveillance programs lack specificity and may capture cases that do not represent current rickettsial infections. Use of IgM antibodies should be reconsidered as a basis for diagnosis and public health reporting of RMSF and other spotted fever group rickettsiae in the United States. PMID:25092818

  16. Toxoplasmosis: the innocent suspect of pregnancy wastage in Duhok, Iraq.

    PubMed

    Razzak, A H; Wais, S A; Saeid, A Y

    2005-07-01

    To identify the true contribution of toxoplasmosis to fetal loss and bad obstetric history, we tested 310 women, 77.4% of whom had had single or multiple fetal loss, for evidence of infection. The study was conducted in Duhok, northern Iraq, from July 2002 till September 2003. All the women were examined for the presence of toxoplasma-specific IgM antibodies by enzyme-linked immunofluorescent assay; only 3 (0.97%) tested positive. We also tested 187 of the women by latex agglutination test; 55 tested positive. Histopathological examination was done for 9 pregnant women who tested positive by the latex agglutination test but we found no evidence of toxoplasma infection. The results indicate that the contribution of toxoplasmosis to fetal loss in our region is greatly overestimated.

  17. Interpretations of antibody responses to Salmonella enterica serotype enteritidis gm flagellin in poultry flocks are enhanced by a kinetics-based enzyme-linked immunosorbent assay.

    PubMed

    McDonough, P L; Jacobson, R H; Timoney, J F; Mutalib, A; Kradel, D C; Chang, Y F; Shin, S J; Lein, D H; Trock, S; Wheeler, K

    1998-07-01

    Many regulatory and diagnostic programs for the detection of Salmonella enterica serotype Enteritidis infection in commercial poultry flocks have relied on rapid Pullorum agglutination tests to screen birds because of the shared antigens of S. enterica Enteritidis and S. enterica Pullorum and Gallinarum; however, the use of the enzyme-linked immunosorbent assay (ELISA) format affords better analytical sensitivity than crude agglutination tests. In this study, we adapted our earlier conventional indirect ELISA, using gm flagellin as the antigen, to a kinetics-based, computer-controlled ELISA (KELA). The KELA was used to screen for flagellin antibody from three commercial flocks: (i) a large flock involved in a U.S. Department of Agriculture trace back from a human S. enterica Enteritidis foodborne outbreak (n = 3,209), (ii) a flock infected with the endemic S. enterica Enteritidis serotype but which also had multiple other Salmonella serotypes (n = 65), and (iii) an S. enterica Pullorum-infected flock (n = 12). The first flock (S. enterica Enteritidis prevalence of 2.45% based on culture) provided a field test of the KELA and allowed the calculation of diagnostic sensitivity (D-Sn) and diagnostic specificity (D-Sp). With a cutoff of 10 (used for screening flocks [i.e., high sensitivity]), the KELA has a D-Sn of 95.2% and a D-Sp of 18.5%; with a cutoff of 140 (used in confirmatory flock testing [i.e., high specificity]), the KELA has a D-Sn of 28.0% and a D-Sp of 99.1%. We found that with a cutoff of 60 (D-Sn = 63.1%; D-Sp = 91.6%), we could eliminate reactions in the KELA caused by other non-S. enterica Enteritidis salmonellae. The KELA was also compared to two commercial rapid Pullorum tests, the Solvay (D-Sn = 94.9%; D-Sp = 55.5%) and the Vineland (D-Sn = 62.0%; D-Sp = 75.3%).

  18. Affective and Behavioral Responses of Gay and Bisexual Men to HIV Antibody Testing.

    ERIC Educational Resources Information Center

    Huggins, James; And Others

    1991-01-01

    Surveyed 56 gay and bisexual men tested for antibody to human immunodeficiency virus. Subjects who tested positive experienced increased anxiety, depression and Acquired Immune Deficiency Syndrome anxiety; subjects who tested negative experienced decrease in these feelings after learning results. Subjects who chose not to learn results experienced…

  19. Serological cross-reactivity between a porcine Actinobacillus strain and Haemophilus pleuropneumoniae.

    PubMed Central

    Rosendal, S; Mittal, K R

    1985-01-01

    During serological screening of a closed SPF-herd free of pleuropneumonia, more than half of the pigs were positive for complement-fixing antibodies to Haemophilus pleuropneumoniae. Actinobacillus bacteria closely related to A. suis were isolated from tonsillar tissue of 14 out of 20 slaughtered pigs submitted for pathological and bacteriological evaluation. None of the pigs had evidence of respiratory disease. Two pigs inoculated endobronchially with a selected Actinobacillus strain developed mild focal pneumonia and complement-fixing antibodies cross-reacting with H. pleuropneumoniae. Five pigs exposed and vaccinated with the Actinobacillus strain and five pigs spontaneously infected with the strain also developed complement-fixing antibodies against H. pleuropneumoniae and appeared to be less susceptible to experimental Haemophilus pleuropneumonia than pigs not exposed to the Actinobacillus infection. The agglutination test applied on serum treated with 2-mercaptoethanol detected antibodies against H. pleuropneumoniae serotype 5 but not against serotype 1 in pigs exposed to the Actinobacillus strain. Antibodies reactive with the Actinobacillus strain were also found in pigs hyperimmunized against H. pleuropneumoniae serotypes 1-5 in 2-mercaptoethanol tube agglutination test and rabbits hyperimmunized against serotypes 1,2 and 7, and strain 73567 in the immunodiffusion test. Conversely rabbits immunized against the Actinobacillus strain had antibodies against H. pleuropneumoniae serotypes 1, 3, 4, 5 and 6. It is concluded that pigs infected with Actinobacillus organisms may become false positive reactors against H. pleuropneumoniae. PMID:3926287

  20. HIV Antibody Testing among Adults in the United States: Data from 1988 NHIS.

    ERIC Educational Resources Information Center

    Hardy, Ann M.; Dawson, Deborah A.

    1990-01-01

    Analyzes statistical data from 1988 National Health Interview Survey to determine adult awareness of and experience with HIV antibody testing. Following findings reported: most knew of test; 17 percent had been tested; Blacks and Hispanics were more likely than Whites to have been voluntarily tested; and high-risk group members were more likely…

  1. Effect of skin test on serum antibody responses to Mycobacterium bovis infection in cattle

    USDA-ARS?s Scientific Manuscript database

    Recently, several serologic tests designed to detect immunodominant antibodies to M. bovis antigens (e.g., MPB83, MPB70, ESAT-6, and CFP10) have emerged for potential use with samples from cattle. Of these, a commercial ELISA to MPB83/MPB70 (M. bovis antibody ELISA) has gained approval for use in ca...

  2. High prevalence of anti-toxoplasma antibodies and absence of Toxoplasma gondii infection risk factors among pregnant women attending routine antenatal care in two Hospitals of Addis Ababa, Ethiopia.

    PubMed

    Gelaye, Woyneshet; Kebede, Tadesse; Hailu, Asrat

    2015-05-01

    Toxoplasmosis is an infection caused by the protozoan parasite Toxoplasma gondii. It is acquired mainly by eating raw or undercooked meat containing Toxoplasma gondii tissue cyst, eating food or water contaminated with oocyst, and acquiring congenital infection through the placenta. This study was conducted to determine the prevalence of toxoplasmosis and assess possible risk factors associated with the infection among pregnant women in Addis Ababa, Ethiopia. Cross sectional study was designed, and 288 serum samples were collected from November 1(st) 2010 to January 2011. The serum samples were tested for anti- Toxoplasma gondii antibodies using latex agglutination test. The risk factors were tested for significance using Bivariate and multivariate analysis. P-value <0.05 was considered statistically significant. 85.4% were positive for anti Toxoplasma gondii antibody. No significant association was observed between seroprevalence and age, gestational age, socio demographic characters, history of abortion, consumption of raw or undercooked meat, consumption of raw vegetable, owning of cat, and blood transfusion. Prevalence of toxoplasmosis among pregnant women in Addis Ababa, Ethiopia is higher than that reported from other countries. Efforts to describe risk factors for toxoplasma infection among Ethiopians should focus in children. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. A scallop C-type lectin from Argopecten irradians (AiCTL5) with activities of lipopolysaccharide binding and Gram-negative bacteria agglutination.

    PubMed

    Mu, Changkao; Song, Xiaoyan; Zhao, Jianmin; Wang, Lingling; Qiu, Limei; Zhang, Huan; Zhou, Zhi; Wang, Mengqiang; Song, Linsheng; Wang, Chunlin

    2012-05-01

    C-type lectins are a family of calcium-dependent carbohydrate-binding proteins. In the present study, a C-type lectin (designated as AiCTL5) was identified and characterized from Argopecten irradians. The full-length cDNA of AiCTL5 was of 673 bp, containing a 5' untranslated region (UTR) of 24 bp, a 3' UTR of 130 bp with a poly (A) tail, and an open reading frame (ORF) of 519 bp encoding a polypeptide of 172 amino acids with a putative signal peptide of 17 amino acids. A C-type lectin-like domain (CRD) containing 6 conserved cysteines and a putative glycosylation sites were identified in the deduced amino acid sequence of AiCTL5. AiCTL5 shared 11%-27.5% identity with the previous reported C-type lectin from A. irradians. The cDNA fragment encoding the mature peptide of AiCTL5 was recombined into pET-21a (+) with a C-terminal hexa-histidine tag fused in-frame, and expressed in Escherichia coli Origami (DE3). The recombinant AiCTL5 (rAiCTL5) agglutinated Gram-negative E. coli TOP10F' and Listonella anguillarum, but did not agglutinate Gram-positive bacteria Bacillus thuringiensis and Micrococcus luteus, and the agglutination could be inhibited by EDTA, indicating that AiCTL5 was a Ca(2+)-dependent lectin. rAiCTL5 exhibited a significantly strong activity to bind LPS from E. coli, which conformed to the agglutinating activity toward Gram-negative bacteria. Moreover, rAiCTL5 also agglutinated rabbit erythrocytes. These results indicated that AiCTL5 could function as a pattern recognition receptor to protect bay scallop from Gram-negative bacterial infection, and also provide evidence to understand the structural and functional diverse of lectin. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Detection of antibodies to egg drop syndrome virus in chicken serum using a field-based immunofiltration (flow-through) test.

    PubMed

    Raj, G Dhinakar; Thiagarajan, V; Nachimuthu, K

    2007-09-01

    A simple, user-friendly, and rapid method to detect the presence of antibodies to egg drop syndrome 76 (EDS) virus in chicken sera based on an immunofiltration (flow-through) test was developed. Purified EDS virus antigen was coated onto nitrocellulose membranes housed in a plastic module with layers of absorbent filter pads underneath. Following addition of serum to be tested and washing, monoclonal antibodies or polyclonal serum to chicken immunoglobulin G (IgG) was used as a bridge antibody to mediate binding between EDS virus-specific IgG and protein A gold conjugate. The appearance of a pink dot indicated the presence of antibodies to EDS virus in the sample tested. The results could be obtained within 5-10 min. The developed immunofiltration test could detect antibodies in the sera of experimentally vaccinated chickens from 2 wk postvaccination. With field sera samples, this test was positive in samples having hemagglutination inhibition titers of 8 and above. This test has the potential to be used as a field-based kit to assess seroconversion in EDS-vaccinated flocks.

  5. Evaluation of a Community's Risk for Canine Parvovirus and Distemper Using Antibody Testing and GIS Mapping of Animal Shelter Intakes.

    PubMed

    Spindel, Miranda E; Krecic, Matthew R; Slater, Margaret R; Vigil, Nicole

    2018-03-20

    This cross-sectional study aimed to identify where dogs with negative antibody tests to canine parvovirus (CPV) and canine distemper virus (CDV) originated when entering a community shelter, using a commercially available ELISA antibody test and Geographic Information Systems mapping. Of 2745 canines entering during a three-month period, 1056 test results were obtained. Dogs or puppies weighing over 2 lb were eligible if they could be humanely, nonchemically restrained for phlebotomy. Age and minor health issues weren't exclusions. Dogs were excluded if trained personnel were concerned health would be compromised by phlebotomy. Blood samples were collected within 24 hours of entry. Four hundred and twenty-seven (40%) dogs had positive antibody test results for both viruses, 422 (40%) were positive for CPV, 37 (4%) were positive for CDV, and 170 (16%) were negative for both. Mapping revealed geographic patterns for dogs with negative antibody tests. This shelter admitted dogs with negative CPV and/or CDV antibody tests from defined community areas. Targeting vaccination efforts in communities to areas where dogs with negative antibody tests originate could be an effective wellness strategy.

  6. Establishment and Evaluation of a One-Step Microplate Chemiluminescence Immunoassay to Detect IgG Antibody Against Treponema Pallidum.

    PubMed

    Liu, Lijuan; Xie, Yuling; Dai, Zhenxian; Zhuo, Chuanshang; Wu, Yushui

    2015-11-01

    The serological detection of specific antibodies against Treponema pallidum is of particular importance in the diagnosis of syphilis. The chemiluminescence immunoassay (CLIA) has been widely used for clinical diagnosis because they remit no radical waste products, cause no enzyme precipitation, and exhibit an excellent sensitivity. A one-step CLIA was established to detect T. pallidum IgG antibody based on microplate coated with a mixture of recombinant T. pallidum antigens TpN15, TpN17, and TpN47. The Chinese national reference substances standard panel for T. pallidum diagnosis was applied to test the accuracy, stability, interference, and cross-reactivity of the established CLIA. The validation of efficacy for clinical application was performed by comparing the established method with the marketed T. pallidum particle agglutination (TPPA) kit and the Abbott ARCHITEC Auto System. The established method met the requirement of the Chinese national reference substances standard for T. pallidum diagnosis. When compared with TPPA (n = 1,052), the specificity, sensitivity, and overall concordance were 99.7%, 99.0%, and 98.8% respectively, showing a great agreement with a kappa value of 0.81. When compared with the Abbott ARCHITEC Auto System (n = 352), the results showed that the specificity, sensitivity, and overall concordance were 98.6.0%, 96.6% and 98.6% respectively, and a high-degree agreement was observed (kappa value = 0.95). The established rapid, specific, sensitive, and stable microplate CLIA method to detect IgG antibody against T pallidum will provide an efficient alternative to the treponemal tests and wide application in clinical laboratory. © 2014 Wiley Periodicals, Inc.

  7. PULMONARY MYCOTIC INFECTIONS—Allergic and Immunologic Factors

    PubMed Central

    Keeney, Edmund L.

    1954-01-01

    The mechanisms of immunity and allergy, at play in every infectious disease, must be comprehended before the pathogenesis of an infection can be appreciated. Immunity, allergy and serology are concerned with specific antigen-antibody reactions. In immunity the principal concern is with the final disposition of antigen (agglutination, lysis, and phagocytosis). In allergy attention is focused upon tissue damage resulting from antigen-antibody union. In serology interest is devoted to the presence of antibody as evaluated by certain visible in vitro reactions—precipitin, agglutination, opsonization and complement fixation tests. There are two types of allergic reaction—the immediate or anaphylactic type and the delayed type or the allergic disease of infection. Neither kind takes part in the mechanism of immunity. At this time the allergic antibody and the immune antibody must be considered as two different and distinct antibodies. Skin and serologic tests are important diagnostic aids in certain pulmonary mycotic infections—for example, coccidioidomycosis, blastomycosis, histoplasmosis and moniliasis. Clinical expressions of allergy may appear in coccidioidomycosis, histoplasmosis and moniliasis. Pulmonary mycoses are divided into three groups, that is, the endogenous mycoses (actinomycosis, moniliasis, geotrichosis), the endogenous-exogenous mycoses (cryptococcosis, aspergillosis, mucormycosis) and the exogenous mycoses (nocardiosis, coccidioidomycosis, histoplasmosis, North American blastomycosis). The diagnosis and treatment of the important mycotic infections that invade lung tissue are discussed. PMID:13209369

  8. Diagnostic performance of serological tests for swine brucellosis in the presence of false positive serological reactions.

    PubMed

    Dieste-Pérez, L; Blasco, J M; de Miguel, M J; Moriyón, I; Muñoz, P M

    2015-04-01

    Swine brucellosis caused by Brucella suis biovar 2 is an emerging disease in Europe. Currently used diagnostic tests for swine brucellosis detect antibodies to the O-polysaccharide (O-PS) of Brucella smooth lipopolysaccharide (S-LPS) but their specificity is compromised by false-positive serological reactions (FPSRs) when bacteria carrying cross-reacting O-PS infect pigs. FPSRs occur throughout Europe, and the only tool available for a specific B. suis diagnosis is the intradermal test with Brucella protein extracts free of O-PS or S-LPS. Using sera of 162 sows naturally infected by B. suis biovar 2, 406 brucellosis-free sows, and 218 pigs of brucellosis-free farms affected by FPSR, we assessed the diagnostic performance of an indirect ELISA with rough LPS (thus devoid of O-PS) and of gel immunodiffusion, counterimmunoelectrophoresis, latex agglutination and indirect ELISA with O-PS free proteins in comparison with several S-LPS tests (Rose Bengal, complement fixation, gel immunodiffusion and indirect ELISA). When adjusted to 100% specificity, the sensitivity of the rough LPS ELISA was very low (30%), and adoption of other cut-offs resulted in poor specificity/sensitivity ratios. Although their specificity was 100%, the sensitivity of protein tests (ELISA, latex agglutination, counterimmunoelectrophoresis, and gel immunodiffusion) was only moderate (45, 58, 61 and 63%, respectively). Among S-LPS tests, gel immunodiffusion was the only test showing acceptable sensitivity/specificity (68 and 100%, respectively). Despite these shortcomings, and when the purpose is to screen out FPSR at herd level, gel immunodiffusion tests may offer a technically simple and practical alternative to intradermal testing. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Acute HIV Discovered During Routine HIV Screening With HIV Antigen-Antibody Combination Tests in 9 US Emergency Departments.

    PubMed

    White, Douglas A E; Giordano, Thomas P; Pasalar, Siavash; Jacobson, Kathleen R; Glick, Nancy R; Sha, Beverly E; Mammen, Priya E; Hunt, Bijou R; Todorovic, Tamara; Moreno-Walton, Lisa; Adomolga, Vincent; Feaster, Daniel J; Branson, Bernard M

    2018-01-05

    Newer combination HIV antigen-antibody tests allow detection of HIV sooner after infection than previous antibody-only immunoassays because, in addition to HIV-1 and -2 antibodies, they detect the HIV-1 p24 antigen, which appears before antibodies develop. We determine the yield of screening with HIV antigen-antibody tests and clinical presentations for new diagnoses of acute and established HIV infection across US emergency departments (EDs). This was a retrospective study of 9 EDs in 6 cities with HIV screening programs that integrated laboratory-based antigen-antibody tests between November 1, 2012, and December 31, 2015. Unique patients with newly diagnosed HIV infection were identified and classified as having either acute HIV infection or established HIV infection. Acute HIV infection was defined as a repeatedly reactive antigen-antibody test result, a negative HIV-1/HIV-2 antibody differentiation assay, or Western blot result, but detectable HIV ribonucleic acid (RNA); established HIV infection was defined as a repeatedly reactive antigen-antibody test result and a positive HIV-1/HIV-2 antibody differentiation assay or Western blot result. The primary outcomes were the number of new HIV diagnoses and proportion of patients with laboratory-defined acute HIV infection. Secondary outcomes compared reason for visit and the clinical presentation of acute HIV infection. In total, 214,524 patients were screened for HIV and 839 (0.4%) received a new diagnosis, of which 122 (14.5%) were acute HIV infection and 717 (85.5%) were established HIV infection. Compared with patients with established HIV infection, those with acute HIV infection were younger, had higher RNA and CD4 counts, and were more likely to have viral syndrome (41.8% versus 6.5%) or fever (14.3% versus 3.4%) as their reason for visit. Most patients with acute HIV infection displayed symptoms attributable to acute infection (median symptom count 5 [interquartile range 3 to 6]), with fever often

  10. When should we test for voltage-gated potassium channel complex antibodies? A retrospective case control study.

    PubMed

    O'Sullivan, B J; Steele, T; Ellul, M A; Kirby, E; Duale, A; Kier, G; Crooks, D; Jacob, A; Solomon, T; Michael, B D

    2016-11-01

    Patients with voltage-gated potassium channel (VGKC)-complex antibodies are increasingly recognized as having central, peripheral or combined phenotypes. With increasing awareness, more patients are tested and the clinical spectrum is expanding. Consequently, clinicians may be uncertain as to which patients should or should not be tested. Previous studies have identified common clinical features, but none has looked at the usefulness of these in predicting seropositive disease. We conducted a case-control study of patients tested for VGKC-complex antibodies over 10years at a regional tertiary neurology centre determining which clinical/biochemical features were associated with antibody-positive disease. We found a marked increase in the numbers tested, although the percentage positive remained low. Antibody titre was highest in central disease (p<0.001). Time from presentation to testing was shorter in those with VGKC-disease (p=0.01). Seizures were present in 11 (69%) of those with VGKC-disease versus three (18%) without (odds ratio [OR] 10.3, 95% confidence interval [CI]: 2.0-52.7, p=0.005). There was an inverse correlation between the antibody titre and serum sodium. A multivariate model selected seizures and hyponatraemia as predictive of VGKC disease (sensitivity 75% and specificity 82%); faciobrachial dystonic movements were specific but insensitive. Interestingly serum alkaline phosphatase was higher in those with VGKC-disease (p=0.016) and highest in those with peripheral disease (p=0.015). An ALP>70u/L was strongly associated with antibody positivity (OR 4.11 95% CI: 1.43-11.8, p=0.007) with a sensitivity of 74.2%. The presence of seizures, faciobrachial movements, and hyponatraemia should raise suspicion of VGKC-disease; alkaline phosphatase may represent a novel biomarker, particularly in those with peripheral disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Anxiety in voluntary HIV-antibody testing in pregnancy and its implications for preventive strategies.

    PubMed

    Foldspang, A; Hedegaard, M

    1991-06-01

    During a three-month period in 1989, 820 pregnant women attending the antenatal clinic of the Aarhus University Hospital, Denmark, were offered a HIV-antibody test and asked to fill out an anonymous questionnaire about attitudes to HIV-antibody testing; 779 (95.0%) agreed to do so. One hundred and fifty-six women (20.0% of the participants) had been tested on a previous occasion, and 629 (80.7%) accepted the present offer to be tested. The most prevalent reasons to decline testing were indifference to the epidemic (45.3% of those declining), refusal of (further) blood testing (34.7%) and fear of being infected (16.7%). Women who consented to be tested most often expressed fear of being infected (21.8%). Fear of registration worried less than 5% of study group members; only 1% declined to be tested because of such worry. The pattern of worries expressed by the pregnant women is interpreted as one of anxiety and, in part at least, perplexity as concerns how to take rational consequences of public messages about the HIV epidemic. It is suggested that future surveillance be based primarily on voluntary testing and, whenever needed and possible, supplied with anonymous unlinked testing of existing blood samples from groups and persons declining to be tested. Such surveillance strategies should be supported in individual patient contacts and public health educational campaigns underscoring the risk of heterosexual transmission of HIV and the need for repeated HIV-antibody testing of selected groups and individuals.

  12. Treponema pallidum western blot: comparison with the FTA-ABS test as a confirmatory test for syphilis.

    PubMed

    Backhouse, J L; Nesteroff, S I

    2001-01-01

    We developed a Treponema pallidum Western blot and compared the results with Treponema pallidum particle agglutination (TPPA) and fluorescent treponemal antibody absorption (FTA-ABS) tests. The Western blot was deemed reactive if the serum reacted with at least three major antigenic bands (TpN47, TpN44.5, TpN17, TpN15). The sensitivities of the Western blot, TPPA and FTA-ABS, were all 100% and the specificities of the Western blot, TPPA and FTA-ABS were 100%, 100% and 94.5% respectively. In 52 problem sera, reactive in only one treponemal test, the agreement between the Western blot and TPPA (61.5%) was significantly better than between Western blot and FTA-ABS (38.5%). The individual sensitivities and specificities of TpN47, TpN44.5, TpN17, TpN15 were 100%, 100%, 96%, 100% and 20%, 96%, 100%, 100% respectively. We conclude that the Western blot is a useful additional confirmatory test or alternative to the FTA-ABS and that a more sensitive and specific criterion for the Western blot would be reactivity with TpN15 and two of the three other major antigens.

  13. A study of the transport and immobilisation mechanisms of human red blood cells in a paper-based blood typing device using confocal microscopy.

    PubMed

    Li, Lizi; Tian, Junfei; Ballerini, David; Li, Miaosi; Shen, Wei

    2013-09-07

    Recent research on the use of bioactive paper for human blood typing has led to the discovery of a new method for identifying the haemagglutination of red blood cells (RBCs). When a blood sample is introduced onto paper treated with the grouping antibodies, RBCs undergo haemagglutination with the corresponding grouping antibodies, forming agglutinated cell aggregates in the paper. A subsequent washing of the paper with saline buffer could not remove these aggregates from the paper; this phenomenon provides a new method for rapid, visual identification of the antibody-specific haemagglutination reactions and thus the determination of the blood type. This study aims to understand the mechanism of RBC immobilization inside the paper which follows haemagglutination reactions. Confocal microscopy is used to observe the morphology of the free and agglutinated RBCs that are labelled with FITC. Chromatographic elution patterns of both agglutinated and non-agglutinated RBCs are studied to gain insight into the transport behaviour of free RBCs and agglutinated aggregates. This work provides new information about RBC haemagglutination inside the fibre network of paper on a microscopic level, which is important for the future design of paper-based blood typing devices with high sensitivity and assaying speed.

  14. Detection of antibodies to Toxoplasma gondii in wild animals in Brazil.

    PubMed

    da Silva, Rodrigo Costa; Machado, Gustavo Puglia; Cruvinel, Tatiane Morosini de Andrade; Cruvinel, Ciro Alexandre; Langoni, Helio

    2014-01-01

    Toxoplasmosis is a worldwide zoonosis caused by an obligate intracellular protozoan parasite, Toxoplasma gondii, that affects all warm-blooded animals, including wild animals. The increased number of cases of parasitic infections is mainly due to the destruction of environmental conservation areas, which is driving wild animals out of their habitats and towards urban areas. In this study, the occurrence of T. gondii infection was investigated by the modified agglutination test (MAT) in 26 different species of run over and injured wild animals that were treated at a Brazilian university veterinary hospital, from June 2007 to August 2008. Of the studied animals, six (23.1%; CI95% 11.1-42.2%) had T. gondii antibodies, with titers equal to 10 (4; 66.7%) and 40 (2; 33.3%). The species Pseudalopex vetulus, Cerdocyon thous, Hydrochoerus hydrochaeris and Tapyrus terrestris had titers of 10, while Alouatta caraya and Puma concolor had titers of 40. There was no significant association regarding age, gender or purpose of care (p > 0.05). Carnivorous, herbivorous and omnivorous wild animals are potential sentinels of human toxoplasmosis, especially when wild felids are present, maintaining the environmental contamination.

  15. Evaluation of monoclonal antibody-based direct, rapid immunohistochemical test for rabies diagnosis.

    PubMed

    Feng, Ye; Wang, Muyang; Liu, Tingfang; Zhang, Yan; Tu, Zhongzhong; Guo, Huancheng; Zhang, Cuijuan; Zhu, Renying; Ren, Wenlin; Sun, Le; Xu, Weidi; Wang, Yuyang; Li, Maohua; Tu, Changchun

    2018-06-01

    Rabies is a major public health problem in developing countries in Asia and Africa. Although a number of laboratory diagnoses can be used for rabies control, the WHO and OIE recommended gold standard for rabies diagnosis is the direct fluorescent antibody test (FAT). However, FAT is not widely used in developing countries because of deficient financial sources to procure fluorescent microscope. Recently the direct rapid immunohistochemical test (dRIT) has been developed and has a worldwide promising application, particularly in developing countries, since its result can be read by inexpensive light microscopy, in addition to be consistent with that of FAT. However, no commercial conjugated antibody is available to meet the laboratory demand. We describe here the production of a monoclonal antibody (MAb) against rabies virus (RABV) N protein and its use as a biotinylated conjugate in a dRIT. Tested against a batch of 107 brain specimens representing a wide phylogenetic diversity of RABV collected from different animal species with multiple geographical origins in China, results showed that the dRIT had 100% specificity (95% CI 0.93-1.00) and 96.49% sensitivity (95% CI 0.88-1.00) as compared with the gold standard FAT. It therefore provides a simple, economical alternative to FAT, particularly for use in rabies diagnosis in developing countries. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Diagnosis of toxoplasmic encephalitis in patients with acquired immunodeficiency syndrome by using a new serologic method.

    PubMed Central

    Suzuki, Y; Israelski, D M; Dannemann, B R; Stepick-Biek, P; Thulliez, P; Remington, J S

    1988-01-01

    The present study was performed to develop a serological method for diagnosing toxoplasmic encephalitis in patients with acquired immunodeficiency syndrome (AIDS). The trophozoite form of Toxoplasma gondii, fixed with either Formalin or acetone, was used in a modification of an agglutination method previously shown to differentiate between the acute and the chronic (latent) stages of infection with toxoplasma in immunologically normal persons. By using these antigens in separate tests and evaluating the data for statistical significance, 70% of patients with AIDS with biopsy-proven toxoplasmic encephalitis were distinguished from control, ambulatory patients with AIDS with toxoplasma antibodies but without signs or symptoms of central nervous system involvement. In a separate study, the agglutination tests identified from controls 84% of patients with AIDS with two or more brain lesions detected by computed-tomographic or magnetic-resonance-imaging scans and suspected of having toxoplasmic encephalitis. Thus, these agglutination tests should prove valuable for the noninvasive diagnosis of toxoplasmic encephalitis in patients with AIDS. PMID:3230132

  17. Clinical interpretation of antinuclear antibody tests in systemic rheumatic diseases

    PubMed Central

    Mercado, Monica Vázquez-Del; Chan, Edward K. L.

    2010-01-01

    Autoantibody tests have been used extensively in diagnosis and follow-up of patients in rheumatology clinics. Immunofluorescent antinuclear antibody test using HEp-2 cells is still considered the gold standard for screening of autoantibodies, and most of specific autoantibodies are currently tested by ELISA as a next step. Among the many autoantibody specificities described, some have been established as clinically useful diagnostic markers and are included in the classification criteria of diseases. Despite a long history of routine tests and attempts to standardize such assays, there are still limitations and problems that clinicians need to be aware of. Clinicians should be able to use autoantibody tests more efficiently and effectively with a basic knowledge on the significance of and potential problems in autoantibody tests. PMID:19277826

  18. Lymphocyte functional antigens stabilize agglutination between Reed-Sternberg cells and T cells, but are not responsible for homotypic binding of Hodgkin's Reed-Sternberg cells.

    PubMed Central

    Hsu, S. M.; Hsu, P. L.

    1990-01-01

    The neoplastic (Hodgkin's Reed-Sternberg [H-RS]) cells in Hodgkin's disease (HD) are known for their unique capacity to form rosettes with unprimed T cells. Recently, a family of leukocyte-adherence molecules (LFA-1 and LFA-2) has been identified on T lymphocytes. The molecules bind to intercellular-adhesion molecules (ICAMs) and to LFA-3, respectively, which are associated with antigen-presenting cells. In this study, the authors examined whether these molecules are responsible for the homotypic and heterotypic agglutination that occurs in the cultured H-RS cells HDLM-1, HDLM-1d, and KM-H2. Despite their similar expressions of LFA-3 and ICAM-1, the different H-RS cells tested showed different growth patterns in culture. HDLM-1 cells grew singly, whereas HDLM-1d and KM-H2 cells grew in clumps. The HDLM-1 cells formed clumps when mixed with peripheral-blood T lymphocytes, cells of two lymphoblastic T-cell lines (MOLT-3 and MOLT-4), and cells of two monocyte lines (ML-1 and U-937). The addition of anti-LFA and ICAM-1 antibodies to cultures did not result in disassembly of the homotypic clusters of HDLM-1d or KM-H2 cells and it did not cause any significant changes in the size of heterotypic clusters or in the timing of cluster formation of HDLM-1 cells with other types of cells. In all studies, the cell clusters formed during homotypic and heterotypic aggregation were disassembled only minimally by cell shearing with pipetting. The disaggregation by pipetting was slightly more prominent in the presence of antibodies than was that of control cultures. However, in no case did the use of monoclonal antibodies (MAbs) and cell shearing cause complete disaggregation of homotypic and heterotypic clusters. The result seems to suggest that binding between H-RS cells and T cells and between H-RS cells and monocytes is not mediated primarily by LFAs and ICAMs, but that the binding may be strengthened in the presence of these molecules. Images Figure 1 Figure 3 Figure 4 Figure 5

  19. Toxoplasmosis in sand fox (Vulpes rueppelli).

    PubMed

    Pas, An; Dubey, J P

    2008-08-01

    Fatal toxoplasmosis was diagnosed in a sand fox (Vulpes rueppelli) from United Arab Emirates. Toxoplasma gondii-like tachyzoites were found associated with necrosis in the intestine, spleen, liver, pancreas, lungs, mesenteric lymph nodes, and heart. Tachyzoites reacted positively with T. gondii-specific polyclonal antibodies. Antibodies to T. gondii were detected in 8 captive V. rueppelli assayed by the modified direct agglutination test in titers of 1:800 or higher.

  20. Glycomics-based analysis of chicken red blood cells provides insight into the selectivity of the viral agglutination assay.

    PubMed

    Aich, Udayanath; Beckley, Nia; Shriver, Zachary; Raman, Rahul; Viswanathan, Karthik; Hobbie, Sven; Sasisekharan, Ram

    2011-05-01

    Agglutination of red blood cells (RBCs), including chicken RBCs (cRBCs), has been used extensively to estimate viral titer, to screen glycan-receptor binding preference, and to assess the protective response of vaccines. Although this assay enjoys widespread use, some virus strains do not agglutinate RBCs. To address these underlying issues and to increase the usefulness of cRBCs as tools for studying viruses, such as influenza, we analyzed the cell surface N-glycans of cRBCs. On the basis of the results obtained from complementary analytical strategies, including MS, 1D and 2D-NMR spectroscopy, exoglycosidase digestions, and HPLC profiling, we report the major glycan structures present on cRBCs. By comparing the glycan structures of cBRCs with those of representative human upper respiratory cells, we offer a possible explanation for the fact that certain influenza strains do not agglutinate cRBCs, using specific human-adapted influenza hemagglutinins as examples. Finally, recent understanding of the role of various glycan structures in high affinity binding to influenza hemagglutinins provides context to our findings. These results illustrate that the field of glycomics can provide important information with respect to the experimental systems used to characterize, detect and study viruses. © 2011 The Authors Journal compilation © 2011 FEBS.

  1. Effects of blood contamination of cerebrospinal fluid on results of indirect fluorescent antibody tests for detection of antibodies against Sarcocystis neurona and Neospora hughesi.

    PubMed

    Finno, Carrie J; Packham, Andrea E; David Wilson, W; Gardner, Ian A; Conrad, Patricia A; Pusterla, Nicola

    2007-05-01

    The purpose of this study was to determine the effect of blood contamination of cerebrospinal fluid (CSF) on the results of indirect fluorescent antibody tests (IFATs) for Sarcocystis neurona and Neospora hughesi. The in vitro study used antibody-negative CSF collected from non-neurologic horses immediately after euthanasia and blood samples from 40 healthy horses that had a range of IFAT antibody titers against S. neurona and N. hughesi. Serial dilutions of whole blood were made in seronegative CSF to generate blood-contaminated CSF with red blood cell (RBC) concentrations ranging from 10 to 100,000 RBCs/microl. The blood-contaminated CSF samples were then tested for antibodies against both pathogens using IFAT. Blood contamination of CSF had no detectable effect on IFAT results for S. neurona or N. hughesi at any serologic titer when the RBC concentration in CSF was <10,000 RBCs/microl. At concentrations of 10,000-100,000 RBCs/microl of CSF, positive CSF results (IFAT titer >or=5) for S. neurona and N. hughesi were detected only when the corresponding serum titers were >or=160 and >or=80, respectively. The IFAT performed on CSF is reliable for testing horses for equine protozoal myeloencephalitis caused by S. neurona or N. hughesi, even when blood contamination causes the RBC concentration in CSF to be up to 10,000 RBCs/microl.

  2. Cross-reactive antibodies in convalescent SARS patients' sera against the emerging novel human coronavirus EMC (2012) by both immunofluorescent and neutralizing antibody tests.

    PubMed

    Chan, Kwok-Hung; Chan, Jasper Fuk-Woo; Tse, Herman; Chen, Honglin; Lau, Candy Choi-Yi; Cai, Jian-Piao; Tsang, Alan Ka-Lun; Xiao, Xincai; To, Kelvin Kai-Wang; Lau, Susanna Kar-Pui; Woo, Patrick Chiu-Yat; Zheng, Bo-Jiang; Wang, Ming; Yuen, Kwok-Yung

    2013-08-01

    A severe acute respiratory syndrome (SARS)-like disease due to a novel betacoronavirus, human coronavirus EMC (HCoV-EMC), has emerged recently. HCoV-EMC is phylogenetically closely related to Tylonycteris-bat-coronavirus-HKU4 and Pipistrellus-bat-coronavirus-HKU5 in Hong Kong. We conducted a seroprevalence study on archived sera from 94 game-food animal handlers at a wild life market, 28 SARS patients, and 152 healthy blood donors in Southern China to assess the zoonotic potential and evidence for intrusion of HCoV-EMC and related viruses into humans. Anti-HCoV-EMC and anti-SARS-CoV antibodies were detected using screening indirect immunofluorescence (IF) and confirmatory neutralizing antibody tests. Two (2.1%) animal handlers had IF antibody titer of ≥ 1:20 against both HCoV-EMC and SARS-CoV with neutralizing antibody titer of <1:10. No blood donor had antibody against either virus. Surprisingly, 17/28 (60.7%) of SARS patients had significant IF antibody titers with 7/28 (25%) having anti-HCoV-EMC neutralizing antibodies at low titers which significantly correlated with that of HCoV-OC43. Bioinformatics analysis demonstrated a significant B-cell epitope overlapping the heptad repeat-2 region of Spike protein. Virulence of SARS-CoV over other betacoronaviruses may boost cross-reactive neutralizing antibodies against other betacoronaviruses. Convalescent SARS sera may contain cross-reactive antibodies against other betacoronaviruses and confound seroprevalence study for HCoV-EMC. Copyright © 2013 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  3. Use of RBC-O and S-MCV parameters of SYSMEX XE-2100 in a patient with RBC cold agglutination.

    PubMed

    Wang, Hong; Lu, Lin; Zhou, Yun; Liu, Jian; Qian, Min; Tang, Weiming; Jie, Zhang; Pan, Shiyang

    2013-01-01

    Sometimes EDTA blood of erythrocyte agglutination cannot be well resolved by incubation at 37 degrees C. In this case report, however, such a specimen was detected from a lymphoma patient at room temperature by using RBC-O and S-MCV parameters of the SYSMEX XE-2100 hematology analyzer. The specimen was diluted with 0.9% NaCL solution at 1:1 before measurement. HCT, MCV, and MCHC, corrected by RBC-O, HGB and S-MCV, were all in their normal ranges. This case indicates that RBC-O and S-MCV parameters of XE-2100 can be used in the routine blood examination of erythrocyte agglutination specimen at room temperature.

  4. Serological tests fail to discriminate dogs with visceral leishmaniasis that transmit Leishmania infantum to the vector Lutzomyia longipalpis.

    PubMed

    Mendonça, Ivete Lopes de; Batista, Joilson Ferreira; Werneck, Guilherme Loureiro; Soares, Maria Regiane Araújo; Costa, Dorcas Lamounier; Costa, Carlos Henrique Nery

    2017-01-01

    The control of reservoirs for Leishmania infantum -induced zoonotic visceral leishmaniasis requires the identification of dogs posing a population risk. Here, we assessed the performance of several assays to identify Lutzomyia longipalpis infectious dogs. We evaluated 99 dogs that were positive for visceral leishmaniasis based on parasite identification. Serological analyses were performed using an enzyme-linked immunosorbent assay, immunofluorescence antibody tests in 1:40 and 1:80 dilutions, rapid dual path platform tests, immunochromatographic assay with a recombinant rK39 antigen, fast agglutination screening tests, and direct agglutination tests. We also performed PCR to analyze peripheral blood and xenodiagnosis. Forty-six dogs infected at least one L. longipalpis specimen. Although the serological test sensitivities were above 85% for detecting L. longipalpis infectious dogs, none showed a satisfactory performance, as both specificity (0.06 to 13%) and the area under the receiver operating characteristic curve (45 to 53%) were low. The PCR results were also weak, with a sensitivity of 30%, specificity of 72%, and an area under the receiver operating characteristic curve of 51%. The infected L. longipalpis proportion was higher among asymptomatic dogs than symptomatic dogs. Among the symptomatic dogs, those with ulceration-free skin diseases were more infectious, with an odds ratio of 9.3 (confidence interval of 1.10 - 428.5). The larger the number of insects fed, the greater the detected infectiousness. Our study supports the imperative to develop novel technologies for identifying the infectious dogs that transmit L. infantum for the benefit of public health.

  5. A Peer Counselling Program for Persons Testing H.I.V. Antibody Positive.

    ERIC Educational Resources Information Center

    Baiss, Alan

    1989-01-01

    Describes need for and development of a peer counseling program for persons who have tested positive for human immunodeficiency virus (HIV) antibodies. Discusses selection of peer counselors, training, and confidentiality. Includes discussion of future plans. (ABL)

  6. Comparison of (1->3)-β-D-glucan, mannan/anti-mannan antibodies, and Cand-Tec Candida antigen as serum biomarkers for candidemia.

    PubMed

    Held, Jürgen; Kohlberger, Isabelle; Rappold, Elfriede; Busse Grawitz, Andrea; Häcker, Georg

    2013-04-01

    We conducted a case-control study using the Fungitell assay, the novel Platelia Candida Antigen (Ag) Plus and Candida Antibody (Ab) Plus assays, and the Cand-Tec latex agglutination test to evaluate the usefulness of (1→3)-β-D-glucan (BDG), mannan antigen with/without anti-mannan antibody, and Cand-Tec Candida antigen measurement for the diagnosis of candidemia. A total of 56 patients fulfilled the inclusion criteria and were enrolled. One hundred patients with bacteremia and 100 patients with sterile blood cultures served as negative controls. In the candidemia group, median (1→3)-β-D-glucan, mannan antigen, and anti-mannan antibody levels were 427 pg/ml, 190 pg/ml, and 18.6 antibody units (AU)/ml, respectively. All three parameters were significantly elevated in patients with candidemia. The sensitivity and specificity were, respectively, 87.5% and 85.5% for (1→3)-β-D-glucan, 58.9% and 97.5% for mannan antigen, 62.5% and 65.0% for anti-mannan antibody, 89.3% and 63.0% for mannan antigen plus anti-mannan antibody, 89.3% and 85.0% for BDG plus mannan antigen, and 13.0% and 93.9% for Cand-Tec Candida antigen. The low mannan antigen sensitivity was in part caused by Candida parapsilosis and Candida guilliermondii fungemias, which were not detected by the Platelia Candida Ag Plus assay. When the cutoff was lowered from 125 pg/ml to 50 pg/ml, mannan antigen sensitivity increased to 69.6% without severely affecting the specificity (93.5%). Contrary to recently published data, superficial candidiasis was not associated with elevated mannan antigen levels, not even after the cutoff was lowered. Combining procalcitonin (PCT) with (1→3)-β-D-glucan to increase specificity provided a limited advantage because the benefit of the combination did not outweigh the loss of sensitivity. Our results demonstrate that the Cand-Tec Candida antigen and the mannan antigen plus anti-mannan antibody measurements have unacceptably low sensitivity or specificity. Of the four

  7. Evaluation of new automated syphilis test reagents 'IMMUNOTICLES AUTO3' series: performance, biochemical reactivity, and clinical significance.

    PubMed

    Yukimasa, Nobuyasu; Miura, Keisuke; Miyagawa, Yukiko; Fukuchi, Kunihiko

    2015-01-01

    Automated nontreponemal and treponemal test reagents based on the latex agglutination method (immunoticles auto3 RPR: ITA3RPR and immunoticles auto3 TP: ITA3TP) have been developed to improve the issues of conventional manual methods such as their subjectivity, a massive amount of assays, and so on. We evaluated these reagents in regards to their performance, reactivity to antibody isotype, and their clinical significance. ITA3RPR and ITA3TP were measured using a clinical chemistry analyzer. Reactivity to antibody isotype was examined by gel filtration analysis. ITA3RPR and ITA3TP showed reactivity to both IgM- and IgG-class antibodies and detected early infections. ITA3RPR was verified to show a higher reactivity to IgM-class antibodies than the conventional methods. ITA3RPR correlated with VDRL in the high titer range, and measurement values decreased with treatment. ITA3RPR showed a negative result earlier after treatment than conventional methods. ITA3TP showed high specificity and did not give any false-negative reaction. Significant differences in the measurement values of ITA3RPR between the infective and previous group were verified. The double test of ITA3RPR and ITA3TP enables efficient and objective judgment for syphilis diagnosis and treatments, achieving clinical availability. Copyright © 2014 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  8. The Dutch Brucella abortus monitoring programme for cattle: the impact of false-positive serological reactions and comparison of serological tests.

    PubMed

    Emmerzaal, A; de Wit, J J; Dijkstra, Th; Bakker, D; van Zijderveld, F G

    2002-02-01

    The Dutch national Brucella abortus eradication programme for cattle started in 1959. Sporadic cases occurred yearly until 1995; the last infected herd was culled in 1996. In August 1999 the Netherlands was declared officially free of bovine brucellosis by the European Union. Before 1999, the programme to monitor the official Brucella-free status of bovine herds was primarily based on periodical testing of dairy herds with the milk ring test (MRT) and serological testing of all animals older than 1 year of age from non-dairy herds, using the micro-agglutination test (MAT) as screening test. In addition, serum samples of cattle that aborted were tested with the MAT. The high number of false positive reactions in both tests and the serum agglutination test (SAT) and complement fixation test (CFT) used for confirmation seemed to result in unnecessary blockade of herds, subsequent testing and slaughter of animals. For this reason, a validation study was performed in which three indirect enzyme-linked immunosorbent assays (ELISAs), the CFT and the SAT were compared using a panel of sera from brucellosis-free cattle, sera from experimentally infected cattle, and sera from cattle experimentally infected with bacteria which are known to induce cross-reactive antibodies (Pasteurella, Salmonella, Yersinia, and Escherichia). Moreover, four ELISAs and the MRT were compared using a panel of 1000 bulk milk samples from Brucella-free herds and 12 milk samples from Brucella abortus- infected cattle. It is concluded that the ELISA obtained from ID-Lelystad is the most suitable test to monitor the brucelosis free status of herds because it gives rise to fewer false-positive reactions than the SAT.

  9. Seroprevalence of Toxoplasma gondii infection in domestic goats in Durango State, Mexico

    USDA-ARS?s Scientific Manuscript database

    Little is known concerning the seroprevalence of Toxoplasma gondii infection in goats in Mexico. Antibodies to T. gondii were determined in 562 goats in Durango, Mexico using the modified agglutination test. Goats were raised in 12 farms in two geographical regions: semi-desert (n=70) and mountains ...

  10. Seroprevalence of Toxoplasma Gondii infection in domestic horses in Durango State, Mexico

    USDA-ARS?s Scientific Manuscript database

    The seroprevalence of Toxoplasma gondii infection in horses in Mexico is unknown. Therefore, antibodies to T. gondii were determined in 495 horses in Durango State, Mexico using the modified agglutination test (MAT). Horses were from 18 farms in 3 municipalities in the valley region of Durango State...

  11. Seroprevalence of Toxoplasma gondii infection in domestic sheep in Durango State, Mexico

    USDA-ARS?s Scientific Manuscript database

    The seroprevalence of Toxoplasma gondii infection in sheep in northern Mexico is largely unknown. Antibodies to T. gondii were determined in serum samples from 511 sheep from 8 farms in Durango State, Mexico using the modified agglutination test (MAT). Sheep were raised in 3 geographical regions, i....

  12. Comparison of hemagglutination inhibition test and ELISA in quantification of antibodies to egg drop syndrome virus.

    PubMed

    Raj, G Dhinakar; Ratnapraba, S; Matheswaran, K; Nachimuthu, K

    2004-01-01

    A single-serum dilution ELISA for egg drop syndrome (EDS) virus-specific antibodies was developed. In testing 425 chicken sera it was found to have a 93.6% sensitivity and 98.7% specificity relative to a hemagglutination inhibition (HI) test. The correlation coefficient for ELISA and HI titers was 0.793. The ELISA was efficacious in quantification of both vaccinal and infection antibodies and could routinely be used for screening large numbers of field sera.

  13. Comparison of counter-immunoelectrophoresis with other serological tests in the diagnosis of human brucellosis

    PubMed Central

    Díaz, R.; Maravi-Poma, E.; Rivero, A.

    1976-01-01

    Sera from 65 persons with clinical brucellosis were employed in a comparison of standard and rapid serological tests. The results obtained with the Rose Bengal test correlated very well with those of the standard tube agglutination test, whereas results with the rapid plate agglutination test and the Coombs (antiglobulin) test were inferior. Absorption of patients' sera with specific anti-human immunoglobulin sera showed that IgM was active in the Rose Bengal test but not in the Coombs test, whereas IgG and IgA were active in both tests. In addition to the A & M antigen, which plays the most important role in the agglutination, Rose Bengal, and Coombs tests, other antigenic fractions of Brucella were examined in precipitation tests. A protein antigen reacted with 94% of the sera in counter-immunoelectrophoresis. On the basis of the results with both groups of sera, the Rose Bengal test and counter-immunoelectrophoresis appear to be the most promising methods for diagnosing clinical brucellosis. The tests differ qualitatively since different Brucella antigens are employed. PMID:791532

  14. Impact of nucleic acid testing relative to antigen/antibody combination immunoassay on the detection of acute HIV infection.

    PubMed

    De Souza, Mark S; Phanuphak, Nittaya; Pinyakorn, Suteeraporn; Trichavaroj, Rapee; Pattanachaiwit, Supanit; Chomchey, Nitiya; Fletcher, James L; Kroon, Eugene D; Michael, Nelson L; Phanuphak, Praphan; Kim, Jerome H; Ananworanich, Jintanat

    2015-04-24

    To assess the addition of HIV nucleic acid testing (NAT) to fourth-generation (4thG) HIV antigen/antibody combination immunoassay in improving detection of acute HIV infection (AHI). Participants attending a major voluntary counseling and testing site in Thailand were screened for AHI using 4thG HIV antigen/antibody immunoassay and sequential less sensitive HIV antibody immunoassay. Samples nonreactive by 4thG antigen/antibody immunoassay were further screened using pooled NAT to identify additional AHI. HIV infection status was verified following enrollment into an AHI study with follow-up visits and additional diagnostic tests. Among 74 334 clients screened for HIV infection, HIV prevalence was 10.9% and the overall incidence of AHI (N = 112) was 2.2 per 100 person-years. The inclusion of pooled NAT in the testing algorithm increased the number of acutely infected patients detected, from 81 to 112 (38%), relative to 4thG HIV antigen/antibody immunoassay. Follow-up testing within 5 days of screening marginally improved the 4thG immunoassay detection rate (26%). The median CD4 T-cell count at the enrollment visit was 353 cells/μl and HIV plasma viral load was 598 289 copies/ml. The incorporation of pooled NAT into the HIV testing algorithm in high-risk populations may be beneficial in the long term. The addition of pooled NAT testing resulted in an increase in screening costs of 22% to identify AHI: from $8.33 per screened patient to $10.16. Risk factors of the testing population should be considered prior to NAT implementation given the additional testing complexity and costs.

  15. Comparison of (1→3)-β-d-Glucan, Mannan/Anti-Mannan Antibodies, and Cand-Tec Candida Antigen as Serum Biomarkers for Candidemia

    PubMed Central

    Kohlberger, Isabelle; Rappold, Elfriede; Busse Grawitz, Andrea; Häcker, Georg

    2013-01-01

    We conducted a case-control study using the Fungitell assay, the novel Platelia Candida Antigen (Ag) Plus and Candida Antibody (Ab) Plus assays, and the Cand-Tec latex agglutination test to evaluate the usefulness of (1→3)-β-d-glucan (BDG), mannan antigen with/without anti-mannan antibody, and Cand-Tec Candida antigen measurement for the diagnosis of candidemia. A total of 56 patients fulfilled the inclusion criteria and were enrolled. One hundred patients with bacteremia and 100 patients with sterile blood cultures served as negative controls. In the candidemia group, median (1→3)-β-d-glucan, mannan antigen, and anti-mannan antibody levels were 427 pg/ml, 190 pg/ml, and 18.6 antibody units (AU)/ml, respectively. All three parameters were significantly elevated in patients with candidemia. The sensitivity and specificity were, respectively, 87.5% and 85.5% for (1→3)-β-d-glucan, 58.9% and 97.5% for mannan antigen, 62.5% and 65.0% for anti-mannan antibody, 89.3% and 63.0% for mannan antigen plus anti-mannan antibody, 89.3% and 85.0% for BDG plus mannan antigen, and 13.0% and 93.9% for Cand-Tec Candida antigen. The low mannan antigen sensitivity was in part caused by Candida parapsilosis and Candida guilliermondii fungemias, which were not detected by the Platelia Candida Ag Plus assay. When the cutoff was lowered from 125 pg/ml to 50 pg/ml, mannan antigen sensitivity increased to 69.6% without severely affecting the specificity (93.5%). Contrary to recently published data, superficial candidiasis was not associated with elevated mannan antigen levels, not even after the cutoff was lowered. Combining procalcitonin (PCT) with (1→3)-β-d-glucan to increase specificity provided a limited advantage because the benefit of the combination did not outweigh the loss of sensitivity. Our results demonstrate that the Cand-Tec Candida antigen and the mannan antigen plus anti-mannan antibody measurements have unacceptably low sensitivity or specificity. Of the four

  16. A Quantitative Method for Comparing the Brightness of Antibody-dye Reagents and Estimating Antibodies Bound per Cell.

    PubMed

    Kantor, Aaron B; Moore, Wayne A; Meehan, Stephen; Parks, David R

    2016-07-01

    We present a quantitative method for comparing the brightness of antibody-dye reagents and estimating antibodies bound per cell. The method is based on complementary binding of test and fill reagents to antibody capture microspheres. Several aliquots of antibody capture beads are stained with varying amounts of the test conjugate. The remaining binding sites on the beads are then filled with a second conjugate containing a different fluorophore. Finally, the fluorescence of the test conjugate compared to the fill conjugate is used to measure the relative brightness of the test conjugate. The fundamental assumption of the test-fill method is that if it takes X molecules of one test antibody to lower the fill signal by Y units, it will take the same X molecules of any other test antibody to give the same effect. We apply a quadratic fit to evaluate the test-fill signal relationship across different amounts of test reagent. If the fit is close to linear, we consider the test reagent to be suitable for quantitative evaluation of antibody binding. To calibrate the antibodies bound per bead, a PE conjugate with 1 PE molecule per antibody is used as a test reagent and the fluorescence scale is calibrated with Quantibrite PE beads. When the fluorescence per antibody molecule has been determined for a particular conjugate, that conjugate can be used for measurement of antibodies bound per cell. This provides comparisons of the brightness of different conjugates when conducted on an instrument whose statistical photoelectron (Spe) scales are known. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  17. 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.

  18. Evaluation of a multiple food specific IgE antibody test compared to parental perception, allergy skin tests and RAST.

    PubMed

    Adler, B R; Assadullahi, T; Warner, J A; Warner, J O

    1991-11-01

    This study was set up to evaluate the food panel of a multiple specific IgE antibody assay in 67 atopic asthmatic children by comparing it to the conventional radioallergosorbent test (RAST) and skin-prick tests (SPT) and then comparing the results of these investigations with the parents' perceptions of food related problems. Fifteen food specific IgE antibodies were measured using the multiple chemiluminescence assay (MAST-CLA). IgE antibodies to five of these food allergens were also measured by conventional RAST and SPTs were performed in 43 using 11 standardized food extracts matched to the multiple allergosorbent chemiluminescent assay (MAST-CLA) profile. SPT and MAST-CLA results showed good agreement with one another, range 68.8-96.7% (average 87%), with significant correlation for most allergens tested. MAST-CLA was discrepant with RAST and/or SPTs in 58/210 (27.6%). A questionnaire was sent to the parents to determine their perception of food related symptoms. Sixty-two (92%) questionnaire replies were received, of which 56% reported symptoms with food. The most frequent symptom perceived to be due to food intolerance was behavioural disturbance. The commonest foods implicated were additives (39%), egg (27%), milk (26%), chocolate (23%) and orange (15%). History, SPT, MAST-CLA and RAST were compared for five allergens in 42 patients (210 values). In 14/210 (6.7%), all the tests were negative despite reported symptoms. Conversely in 49/210 (23.3%) at least one test was positive without symptoms. This study did not support a benefit of multipole testing instead of individually selected RASTs or SPTs.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Prevalence of Toxoplasma gondii antibodies in domestic donkeys (Equus asinus) in Durango, Mexico slaughtered for human consumption.

    PubMed

    Alvarado-Esquivel, Cosme; Alvarado-Esquivel, Domingo; Dubey, Jitender P

    2015-01-17

    Nothing is known about Toxoplasma gondii prevalence in donkeys in Mexico. Meat from donkey is consumed by humans in Mexico and also exported to other countries. We sought to determine the presence of antibodies against T. gondii in 239 domestic donkeys (Equus asinus) for slaughter in Durango, Mexico using the modified agglutination test (MAT). Donkeys were sampled in four premises (trade centers) where donkeys were gather for shipment to abattoirs in other Mexican states. Antibodies to T. gondii were found in 26 (10.9%) of 239 donkeys, with MAT titers of 1:25 in 7, 1:50 in 11, 1:100 in 6, and 1:200 in 2. Seropositive donkeys were found in three (75%) of the four gathering premises studied. Seroprevalence in donkeys varied from 0% to 23.1% among gathering premises. The seroprevalence of T. gondii infection was comparable among donkeys regardless their age, sex or health status. Seropositivity to T. gondii was found in donkeys between 1 to 12 years old. Multivariate analysis showed that seropositivity to T. gondii was associated with the gathering premises (OR = 1.58; 95% CI: 1.11-2.24; P = 0.009). This is the first report of T. gondii infection in donkeys in Mexico. Results indicate that consumption of undercooked or raw meat from T. gondii-infected donkeys is potentially a source of T. gondii infection for humans.

  20. Mechanistic Evaluation for Mixed-field Agglutination in the K562 Cell Study Model with Exon 3 Deletion of A1 Gene.

    PubMed

    Chen, Ding-Ping; Tseng, Ching-Ping; Lin, Chi-Jui; Wang, Wei-Ting; Sun, Chien-Feng

    2015-01-01

    In the case of blood type B3 with typical mixed-field agglutination of RBCs in the presence of anti-B or anti-AB antibody, a number of genetic alternations have been reported. It is well known that the IVS3+5G→A mutation in the B gene destroys the consensus of the splice donor site leading to exon 3 skipping during mRNA splicing. The lack of exon 3 likely causes a short stem region, producing an unstable B3 protein, and is concomitant with a decrease in B3 protein expression. Whether the phenomenon also appears in the type A blood group is of question. In this study, we evaluate whether exon 3 deletion in the blood type A gene also results in mixed-field phenotype. Site-directed mutagenesis was used to generate cDNA encoding A1 gene with exon 3 deletion. The cDNA was stably expressed in K562 cells. The expression of A antigen was compared with expression in parental K562 cells that did not express A antigen and in the stable K562 cell line expressing A(1) cDNA by flow cytometry analyses. The expression of A antigen in A1 stable cells and parental K562 cells was set as 100% and 0%, respectively. The mean relative percentage of A antigen expression for the cells of A1 with exon 3 deletion was 59.9% of A1 stable cells. Consistent with the observations of B3, which is B gene with exon 3 deletion, mixed field agglutination was observed for the cells expressing A1 with exon 3 deletion. Exon 3 deletion results in mixed field phenotype in both type A and B RBCs. However, the degree of antigen expression change for exon 3 deletion in A gene was less severe when compared with the deletion occurred in B gene. © 2015 by the Association of Clinical Scientists, Inc.

  1. Isolation and genetic characterization of Toxoplasma gondii from mute swan (Cygnus olor) from the USA

    USDA-ARS?s Scientific Manuscript database

    Little is known of the genetic diversity of Toxoplasma gondii circulating in wildlife. In the present study, antibodies to T. gondii were determined in serum samples from 632 mute swans (Cygnus olor) collected from different areas of the USA. Sera were tested by T. gondii modified agglutination te...

  2. Isolation and RFLP genotyping of toxoplasma gondii in free-range chicken(Gallus domesticus) in Grenada, West Indies, revealed widespread and dominance of clonal type III parasites

    USDA-ARS?s Scientific Manuscript database

    The objectives of the present cross sectional study were to estimate the prevalence and to isolate and genotype Toxoplasma gondii in free range chickens from Grenada, West Indies. Using the modified agglutination test, antibodies to T. gondii were found in 39 (26.9%) of 145 free-range chickens with ...

  3. PF4/heparin antibody testing and treatment of heparin-induced thrombocytopenia in the intensive care unit.

    PubMed

    Wanat, Matthew; Fitousis, Kalliopi; Hall, Jeff; Rice, Lawrence

    2013-06-01

    The diagnosis of heparin-induced thrombocytopenia (HIT) may be challenging in critically ill patients, as heparin exposures are ubiquitous, and thrombocytopenia is common. Unwarranted ordering and incorrect interpretation of heparin antibody tests can expose a patient to adverse drug events and imposes a significant economic burden on our health care system. A prospective, observational study was performed over 4 months on all adult patients located in 5 intensive care units, with a heparin antibody test ordered. A platelet factor 4/heparin enzyme-linked immunosorbent assay (ELISA) test was ordered in 131 patients. In total, 110 patients had a low 4Ts score (0-3), and of these 103 had a negative ELISA result. In patients with a low 4Ts score, 0 (0%) of 110 had an optical density value >1.0. One hundred twenty-nine patients (98%) had another possible cause of thrombocytopenia identified. In critically ill patients, low 4Ts scores indicate a low probability of HIT, and heparin antibody testing in these patients is not useful.

  4. Interference of daratumumab with pretransfusion testing, mimicking a high-titer, low avidity like antibody.

    PubMed

    Lin, Mei-Hwa; Liu, Fei-Yun; Wang, Hsiu-Mien; Cho, Hsin-Ching; Lo, Shyh-Chyi

    2017-01-01

    Daratumumab is a monoclonal immunoglobulin against CD38 and has been approved for treating patients with refractory multiple myeloma. The presence of daratumumab in the sera can interfere with pretransfusion testing due to the weakly expression of CD38 on red cells. The reactivity could be mistaken as autoantibody (if autocontrol is positive) or alloantibody (if autocontrol is negative). We present a case that demonstrates daratumumab could mimic a high titer low avidity (HTLA) alloantibody. A 34-year-old male patient of refractory myeloma was recruited in phase three clinical trial involving daratumumab. Samples were sent to the blood bank for pretransfusion testing. Without knowledge of patient having used daratumumab, we mistook the reactivity in the patient's sera as an HTLA antibody due to the results of negative autocontrol and high titers of antibody activity. Antibody screen showed a panreactive pattern and the reactivity against screening cells was up to a titer of 1: 1240. The reactivity was weaker against cord cells than adult cells, became weaker against ZZAP-treated cells and became negative against DDT-treated cells. A discussion with attending physician finally revealed the reactivity was due to the interference caused by daratumumab. The case demonstrates good communication is essential in performing pretransfusion testing for patients receiving daratumumab and other new biological regimens that can interfere with compatibility test.

  5. Interference of daratumumab with pretransfusion testing, mimicking a high-titer, low avidity like antibody

    PubMed Central

    Lin, Mei-Hwa; Liu, Fei-Yun; Wang, Hsiu-Mien; Cho, Hsin-Ching; Lo, Shyh-Chyi

    2017-01-01

    Daratumumab is a monoclonal immunoglobulin against CD38 and has been approved for treating patients with refractory multiple myeloma. The presence of daratumumab in the sera can interfere with pretransfusion testing due to the weakly expression of CD38 on red cells. The reactivity could be mistaken as autoantibody (if autocontrol is positive) or alloantibody (if autocontrol is negative). We present a case that demonstrates daratumumab could mimic a high titer low avidity (HTLA) alloantibody. A 34-year-old male patient of refractory myeloma was recruited in phase three clinical trial involving daratumumab. Samples were sent to the blood bank for pretransfusion testing. Without knowledge of patient having used daratumumab, we mistook the reactivity in the patient's sera as an HTLA antibody due to the results of negative autocontrol and high titers of antibody activity. Antibody screen showed a panreactive pattern and the reactivity against screening cells was up to a titer of 1: 1240. The reactivity was weaker against cord cells than adult cells, became weaker against ZZAP-treated cells and became negative against DDT-treated cells. A discussion with attending physician finally revealed the reactivity was due to the interference caused by daratumumab. The case demonstrates good communication is essential in performing pretransfusion testing for patients receiving daratumumab and other new biological regimens that can interfere with compatibility test. PMID:28970695

  6. Thyroid Antibodies

    MedlinePlus

    ... been associated with reproductive difficulties, such as miscarriage, pre-eclampsia , premature delivery, and in-vitro fertilization failure Thyroglobulin antibody TgAb Thyroid cancer ; Hashimoto thyroiditis Whenever a thyroglobulin test is performed to see if the antibody is ...

  7. Immunochemical Parameters of Some Commercial Conjugates for the Fluorescent Treponemal Antibody-Absorption Test

    PubMed Central

    Hunter, E. F.; Smith, J. F.; Lewis, J. S.; McGrew, B. E.; Schmale, J. D.

    1972-01-01

    Fluorescein-labeled anti-human globulins were examined to determine the need for standardization of conjugates used in the fluorescent treponemal antibody-absorption (FTA-ABS) test. Twenty-one of 33 conjugates submitted by commercial manufacturers to the Reagents Control Activity, Venereal Disease Research Laboratory, for evaluation in the FTA-ABS test were available for study. Conjugates, after evaluation in FTA-ABS performance tests, were examined by immunoelectrophoresis, by titration against immunoglobulins G and M (IgG, IgM) with FTA-ABS techniques, and by the biuret protein and fluorescein diacetate methods for determining fluorescein to protein (F/P) ratios. The conjugates were predominately anti-IgG globulin with anti-light-chain activity. Differences were noted in the ability of some conjugates to detect IgM antibody. The F/P ratios of those conjugates that could be determined varied from 2.6 to 17.8 μg of fluorescein per mg of protein. The need to identify and standardize both the immunologic capabilities and the optimum F/P ratio for FTA-ABS test conjugates is presented. PMID:4564403

  8. Serological study of brucellosis in Argentine Creole sheep.

    PubMed

    López, Gustavo E; Peña, Sabrina; Escobar, Gabriela I; Hasan, Déborah B; Lucero, Nidia E

    2018-01-05

    Ovine cattle was introduced into America during the Spanish conquest with the second journey of Columbus to the Antilles and was disseminated throughout the region. In 1587, sheep were introduced into Argentina, later developing into the "Creole" breed. We selected 486 animals from different Argentine provinces with the aim of determining the serological status of brucellosis caused by Brucella melitensis and Brucella ovis. For the detection of antibodies against smooth Brucella spp., the Rose Bengal test (RBT) was performed as screening test while the serum agglutination test (SAT) and 2 mercapto-ethanol (2ME) were run as a confirmatory technique. Moreover, for the detection of antibodies against rough Brucella spp., we used the rapid slide agglutination test (RSAT) for screening and an indirect ELISA (IELISA) as confirmatory assay. This study showed that the total positive percentage of brucellosis due to B. ovis was 2.9%. Excluding the animals mixed with the Suffolk breed; seropositivity would be 0.6%. All animals tested negative for brucellosis caused by B. melitensis. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Biologically agglutinated eukaryotic microfossil from Cryogenian cap carbonates.

    PubMed

    Moore, K R; Bosak, T; Macdonald, F A; Lahr, D J G; Newman, S; Settens, C; Pruss, S B

    2017-07-01

    Cryogenian cap carbonates that overlie Sturtian glacial deposits were formed during a post-glacial transgression. Here, we describe microfossils from the Kakontwe Formation of Zambia and the Taishir Formation of Mongolia-both Cryogenian age, post-Sturtian cap carbonates-and investigate processes involved in their formation and preservation. We compare microfossils from these two localities to an assemblage of well-documented microfossils previously described in the post-Sturtian Rasthof Formation of Namibia. Microfossils from both new localities have 10 ± 1 μm-thick walls composed of carbonaceous matter and aluminosilicate minerals. Those found in the Kakontwe Formation are spherical or ovoid and 90 ± 5 μm to 200 ± 5 μm wide. Structures found in the Taishir Formation are mostly spherical, 50 ± 5 μm to 140 ± 5 μm wide, with distinct features such as blunt or concave edges. Chemical and mineralogical analyses show that the walled structures and the clay fraction extracted from the surrounding sediments are composed of clay minerals, especially muscovite and illite, as well as quartz, iron and titanium oxides, and some dolomite and feldspar. At each locality, the mineralogy of the microfossil walls matched that of the clay fractions of the surrounding sediment. The abundance of these minerals in the walled microfossils relative to the surrounding carbonate matrix and microbial laminae, and the presence of minerals that cannot precipitate from solution (titanium oxide and feldspar), suggests that the composition represents the original mineralogy of the structures. Furthermore, the consistency in mineralogy of both microfossils and sediments across the three basins, and the uniformity of size and shape among mineral grains in the fossil walls indicate that these organisms incorporated these minerals by primary biological agglutination. The discovery of new, mineral-rich microfossil assemblages in microbially laminated and other fine

  10. Should we systematically test patients with clinically isolated syndrome for auto-antibodies?

    PubMed

    Negrotto, Laura; Tur, Carmen; Tintoré, Mar; Arrambide, Georgina; Sastre-Garriga, Jaume; Río, Jordi; Comabella, Manuel; Nos, Carlos; Galán, Ingrid; Vidal-Jordana, Angela; Simon, Eva; Castilló, Joaquín; Palavra, Filipe; Mitjana, Raquel; Auger, Cristina; Rovira, Àlex; Montalban, Xavier

    2015-12-01

    Several autoimmune diseases (ADs) can mimic multiple sclerosis (MS). For this reason, testing for auto-antibodies (auto-Abs) is often included in the diagnostic work-up of patients with a clinically isolated syndrome (CIS). The purpose was to study how useful it was to systematically determine antinuclear-antibodies, anti-SSA and anti-SSB in a non-selected cohort of CIS patients, regarding the identification of other ADs that could represent an alternative diagnosis. From a prospective CIS cohort, we selected 772 patients in which auto-Ab levels were tested within the first year from CIS. Baseline characteristics of auto-Ab positive and negative patients were compared. A retrospective revision of clinical records was then performed in the auto-Ab positive patients to identify those who developed ADs during follow-up. One or more auto-Ab were present in 29.4% of patients. Only 1.8% of patients developed other ADs during a mean follow-up of 6.6 years. In none of these cases the concurrent AD was considered the cause of the CIS. In all cases the diagnosis of the AD resulted from the development of signs and/or symptoms suggestive of each disease. Antinuclear-antibodies, anti-SSA and anti-SSB should not be routinely determined in CIS patients but only in those presenting symptoms suggestive of other ADs. © The Author(s), 2015.

  11. Antibodies and Selection of Monoclonal Antibodies.

    PubMed

    Hanack, Katja; Messerschmidt, Katrin; Listek, Martin

    Monoclonal antibodies are universal binding molecules with a high specificity for their target and are indispensable tools in research, diagnostics and therapy. The biotechnological generation of monoclonal antibodies was enabled by the hybridoma technology published in 1975 by Köhler and Milstein. Today monoclonal antibodies are used in a variety of applications as flow cytometry, magnetic cell sorting, immunoassays or therapeutic approaches. First step of the generation process is the immunization of the organism with appropriate antigen. After a positive immune response the spleen cells are isolated and fused with myeloma cells in order to generate stable, long-living antibody-producing cell lines - hybridoma cells. In the subsequent identification step the culture supernatants of all hybridoma cells are screened weekly for the production of the antibody of interest. Hybridoma cells producing the antibody of interest are cloned by limited dilution till a monoclonal hybridoma is found. This is a very time-consuming and laborious process and therefore different selection strategies were developed since 1975 in order to facilitate the generation of monoclonal antibodies. Apart from common automation of pipetting processes and ELISA testing there are some promising approaches to select the right monoclonal antibody very early in the process to reduce time and effort of the generation. In this chapter different selection strategies for antibody-producing hybridoma cells are presented and analysed regarding to their benefits compared to conventional limited dilution technology.

  12. [Adult T-cell leukemia/lymphoma associated with unusual positivity of anti-ATLA (adult T-cell leukemia-cell-associated antigen) antibodies].

    PubMed

    Eto, T; Okamura, H; Okamura, T; Gondo, H; Kudo, J; Shibuya, T; Harada, M; Niho, Y

    1990-03-01

    A 56-year-old female was admitted because of generalized lymphadenopathy. Based upon histological findings of biopsied lymph node, malignant lymphoma, diffuse large cell type was diagnosed. The surface marker analysis showed that malignant cells were positive for CD4 and CD2 but negative for CD8. Although anti-ATLA (adult T-cell leukemia associated antigen) antibody was negative with the use of a gelatin particle agglutination method (P.A.), other methods such as an indirect immunofluorescence assay (I.F.), an enzyme-linked immunosorbent assay (E.I.A.) and a Western blotting assay revealed the positivity for anti-ATLA antibody. Adult T-cell leukemia/lymphoma (ATL/L) was confirmed by the presence of monoclonal integration of HTLV-I proviral DNA in biopsied specimen. This case, showing a pattern of P.A. (-) and I.F. (+), is extremely unusual, because I.F. and P.A. show highly close correlation. Thus, it is important to employ different methods for screening of anti-ATLA antibodies in the diagnosis of ATL/L.

  13. Toxoplasmosis in Caribbean islands: Seroprevalence in pregnant women in ten countries, and isolation and report of new genetic types of Toxoplasma gondii from dogs from St. Kitts, West Indies

    USDA-ARS?s Scientific Manuscript database

    Little is known of clinical toxoplasmosis in humans and animals in the Caribbean countries. We investigated the prevalence of IgG and IgMantibodies in 437 pregnant women from 10 English speaking Caribbean countries. Antibodies (IgG) to T. gondii (modified agglutination test, MAT, cut-off 1:6) were f...

  14. A Descriptive Analysis of Students Seeking HIV Antibody Testing at a University Health Service.

    ERIC Educational Resources Information Center

    Anastasi, Marie-Christine; Sawyer, Robin G.; Pinciaro, Paul J.

    1999-01-01

    Investigated characteristics of students voluntarily seeking human immunodeficiency virus (HIV) antibody testing at a university health center. Data from student surveys indicated that: 59% were women; reported rates of unintended pregnancy and sexually transmitted diseases were low; nearly one-third had had previous HIV testing; 40% reported…

  15. Properties of Streptococcus mutans Grown in a Synthetic Medium: Binding of Glucosyltransferase and In Vitro Adherence, and Binding of Dextran/Glucan and Glycoprotein and Agglutination

    PubMed Central

    Wu-Yuan, Christine D.; Tai, Stella; Slade, Hutton D.

    1979-01-01

    The influence of culture media on various properties of Streptococcus mutans was investigated. Strains of S. mutans (serotypes c, d, f, and g) were grown in a complex medium (Todd-Hewitt broth [THB]) or a synthetic medium (SYN). The SYN cells, in contrast to THB cells, did not bind extracellular glucosyltransferase and did not produce in vitro adherence. Both types of cells possessed constitutive levels of glucosyltransferase. B13 cells grown in SYN plus invertase-treated glucose possessed the same level of constitutive enzyme as THB cells. In contrast to THB cells, the SYN cells of seven serotype strains did not agglutinate upon the addition of high-molecular-weight dextran/glucan. Significant quantities of lower-molecular-weight (2 × 104 or 7 × 104) dextran and B13 glucan were bound by SYN cells. SYN cells agglutinated weakly in anti-glucan serum (titers, 0 to 16), whereas THB cells possessed titers of 32 to 256. Evidence for the existence of a second binding site in agglutination which does not possess a glucan-like polymer has been obtained. B13 cells grown in invertase-treated THB agglutinated to the same degree as normal THB cells. The nature of this site is unknown. SYN cells possess the type-specific polysaccharide antigen. B13 cells did not bind from THB a glycoprotein which reacts with antisera to the A, B, or T blood group antigens or which allows agglutination upon the addition of dextran. The results demonstrate that S. mutans grown in a chemically defined medium possesse markedly different biochemical and biological activities than cells grown in a complex organic medium. PMID:457252

  16. Evaluation of the Lumipulse G TP-N Chemiluminescent Immunoassay as a Syphilis Screening Test

    PubMed Central

    Ortiz, Daniel A.

    2017-01-01

    ABSTRACT A syphilis diagnosis is often aided by the detection of treponemal and nontreponemal antibodies. Automated treponemal antibody detection systems enable high-volume clinical laboratories to perform syphilis screening at a faster pace with lower labor costs. The Lumipulse G TP-N chemiluminescent immunoassay is an automated system that qualitatively detects IgG and IgM antibodies against Treponema pallidum antigens in human serum and plasma. To assess performance characteristics and workflow efficiency, the Lumipulse G TP-N assay was compared to the Bioplex 2200 Syphilis IgG multiplex flow immunoassay. Among the 4,134 routine and HIV samples tested by the two automated assays, the percentage of agreement was excellent at 99.0% (95% confidence interval [CI], 98.6% to 99.2%; κ, 0.89), with the Lumipulse G TP-N having a shorter time to first and subsequent results. All specimens with reactive syphilis screening results were further tested by rapid plasma reagin (RPR) and Treponema pallidum particle agglutination (TP·PA) testing (n = 231). The results from the RPR-reactive samples (n = 82) showed complete concordance with the two automated assays, while the TP·PA assay displayed some discrepancies. The positive percent agreement (PPA) and negative percent agreement (NPA) between the TP·PA test and the Lumipulse G TP-N test were 98.9% and 77.3%, respectively. The Bioplex 2200 Syphilis IgG immunoassay displayed a similar PPA (100%) but a substantially lower NPA (15.9%). Patient chart reviews of discrepant results suggested that the Lumipulse G TP-N assay produced 27 fewer falsely reactive results and can reduce the amount of additional confirmatory RPR and TP·PA testing needed. The analogous performance characteristics of the two automated systems indicate that the Lumipulse G TP-N assay is suitable for high-throughput syphilis screening. PMID:28878003

  17. Evaluation of the Lumipulse G TP-N Chemiluminescent Immunoassay as a Syphilis Screening Test.

    PubMed

    Ortiz, Daniel A; Loeffelholz, Michael J

    2017-11-01

    A syphilis diagnosis is often aided by the detection of treponemal and nontreponemal antibodies. Automated treponemal antibody detection systems enable high-volume clinical laboratories to perform syphilis screening at a faster pace with lower labor costs. The Lumipulse G TP-N chemiluminescent immunoassay is an automated system that qualitatively detects IgG and IgM antibodies against Treponema pallidum antigens in human serum and plasma. To assess performance characteristics and workflow efficiency, the Lumipulse G TP-N assay was compared to the Bioplex 2200 Syphilis IgG multiplex flow immunoassay. Among the 4,134 routine and HIV samples tested by the two automated assays, the percentage of agreement was excellent at 99.0% (95% confidence interval [CI], 98.6% to 99.2%; κ, 0.89), with the Lumipulse G TP-N having a shorter time to first and subsequent results. All specimens with reactive syphilis screening results were further tested by rapid plasma reagin (RPR) and Treponema pallidum particle agglutination (TP·PA) testing ( n = 231). The results from the RPR-reactive samples ( n = 82) showed complete concordance with the two automated assays, while the TP·PA assay displayed some discrepancies. The positive percent agreement (PPA) and negative percent agreement (NPA) between the TP·PA test and the Lumipulse G TP-N test were 98.9% and 77.3%, respectively. The Bioplex 2200 Syphilis IgG immunoassay displayed a similar PPA (100%) but a substantially lower NPA (15.9%). Patient chart reviews of discrepant results suggested that the Lumipulse G TP-N assay produced 27 fewer falsely reactive results and can reduce the amount of additional confirmatory RPR and TP·PA testing needed. The analogous performance characteristics of the two automated systems indicate that the Lumipulse G TP-N assay is suitable for high-throughput syphilis screening. Copyright © 2017 American Society for Microbiology.

  18. Epidemiology of Sarcocystis neurona infections in domestic cats (Felis domesticus) and its association with equine protozoal myeloencephalitis (EPM) case farms and feral cats from a mobile spay and neuter clinic.

    PubMed

    Stanek, J F; Stich, R W; Dubey, J P; Reed, S M; Njoku, C J; Lindsay, D S; Schmall, L M; Johnson, G K; LaFave, B M; Saville, W J A

    2003-11-28

    Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease in the horse most commonly caused by Sarcocystis neurona. The domestic cat (Felis domesticus) is an intermediate host for S. neurona. In the present study, nine farms, known to have prior clinically diagnosed cases of EPM and a resident cat population were identified and sampled accordingly. In addition to the farm cats sampled, samples were also collected from a mobile spay and neuter clinic. Overall, serum samples were collected in 2001 from 310 cats, with samples including barn, feral and inside/outside cats. Of these 310 samples, 35 were from nine horse farms. Horse serum samples were also collected and traps were set for opossums at each of the farms. The S. neurona direct agglutination test (SAT) was used for both the horse and cat serum samples (1:25 dilution). Fourteen of 35 (40%) cats sampled from horse farms had circulating S. neurona agglutinating antibodies. Twenty-seven of the 275 (10%) cats from the spay/neuter clinic also had detectable S. neurona antibodies. Overall, 115 of 123 (93%) horses tested positive for anti-S. neurona antibodies, with each farm having greater than a 75% exposure rate among sampled horses. Twenty-one opossums were trapped on seven of the nine farms. Eleven opossums had Sarcocystis sp. sporocysts, six of them were identified as S. neurona sporocysts based on bioassays in gamma-interferon gene knockout mice with each opossum representing a different farm. Demonstration of S. neurona agglutinating antibodies in domestic and feral cats corroborates previous research demonstrating feral cats to be naturally infected, and also suggests that cats can be frequently infected with S. neurona and serve as one of several natural intermediate hosts for S. neurona.

  19. Saliva antibody testing and vaccination in a mumps outbreak.

    PubMed

    Ramsay, M E; Brown, D W; Eastcott, H R; Begg, N T

    1991-08-16

    Saliva antibody testing was performed to describe the epidemiology of an outbreak of mumps and identify susceptible children. Thirty-three out of 171 children (19%) were designated susceptible. A past history of mumps illness was found to be unreliable. No further cases of mumps were notified after 28 susceptible children were given MMR vaccine. The use of MMR vaccination may have contributed to the control of this outbreak and its use should be considered where a defined population is expected to have a significant proportion of susceptible individuals.

  20. An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of sodium and potassium feldspars

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

    1985-01-01

    The results of an experiment designed to test the validity of the model for agglutinate formation involving fusion of the finest fraction or F3 are reported. Impact glasses were formed from various mixes of orthoclase and albite powders, which were used as analogs for soils with chemically constrasting coarse and fine fractions. The results showed that the single most important factor displacing the composition of a small-scale impact melt from the bulk composition of the source regolith is the fractionated composition of the finest soil fraction. Volatile loss and the amount of melting, which in turn are determined by the degree of shock, are also important. As predicted by the model, the lower pressure melts are the most fractionated, and higher pressure is accompanied by increased melting causing glass compositions to approach the bulk. In general, the systematics predicted by the model are observed; the model appears to be valid.

  1. Chikungunya virus RNA and antibody testing at a National Reference Laboratory since the emergence of Chikungunya virus in the Americas.

    PubMed

    Prince, Harry E; Seaton, Brent L; Matud, Jose L; Batterman, Hollis J

    2015-03-01

    Since first reported in the Americas in December 2013, chikungunya virus (CHIKV) infections have been documented in travelers returning from the Caribbean, with many cases identified by CHIKV antibody and/or RNA testing at our laboratory. We used our large data set to characterize the relationship between antibody titers and RNA detection and to estimate IgM persistence. CHIKV RNA was measured by nucleic acid amplification and CHIKV IgG/IgM by indirect immunofluorescence. Of the 1,306 samples submitted for RNA testing in January through September 2014, 393 (30%) were positive; for 166 RNA-positive samples, CHIKV antibody testing was also ordered, and 84% were antibody negative. Of the 6,971 sera submitted for antibody testing in January through September 2014, 1,811 (26%) were IgM positive; 1,461 IgM positives (81%) were also IgG positive. The relationship between the CHIKV antibody titers and RNA detection was evaluated using 376 IgM-positive samples (138 with RNA testing ordered and 238 deidentified and tested for RNA). RNA detection showed no significant association with the IgM titer but was inversely related to the IgG titer; 63% of the IgG negative sera were RNA positive, compared to 36% of sera with low IgG titers (1:10 to 1:80) and 16% with IgG titers of ≥1:160. Using second-sample results from 62 seroconverters, we estimated that CHIKV IgM persists for 110 days (95% confidence interval, 78 to 150 days) after the initial antibody-negative sample. These findings indicate that (i) RNA detection is more sensitive than antibody detection early in CHIKV infection, (ii) in the absence of RNA results, the IgG titer of the IgM-positive samples may be a useful surrogate for viremia, and (iii) CHIKV IgM persists for approximately 4 months after symptom onset. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  2. A type-specific serological test to distinguish antibodies to equine herpesviruses 4 and 1.

    PubMed

    Crabb, B S; MacPherson, C M; Reubel, G H; Browning, G F; Studdert, M J; Drummer, H E

    1995-01-01

    We describe a type-specific ELISA, which distinguishes antibody to equine herpesvirus 4 (EHV4; equine rhinopneumonitis) and EHV1 (equine abortion virus) thereby identifying horses that have been infected with either or both of these antigenically related viruses. The antigens used are parts of the EHV4 and EHV1 glycoprotein G (gG) homologues expressed in E. coli as fusion proteins [Crabb and Studdert, 1993: J Virol 67: 6332-6338). The expressed proteins comprise corresponding regions of the gG molecules that are highly divergent and encompass strong, typespecific epitopes. Plasma samples from 97 Thoroughbred and 174 Standardbred horses were tested, all of which were unvaccinated. All horses were strongly EHV4 ELISA positive while 30% were EHV1 ELISA positive. The type-specificity of the EHV1 gG antigen was tested in cross-absorption experiments and it was found that 96% (66 of 69) of EHV1 ELISA positive horses were true EHV1 antibody positives. It was also shown that 100% (26 of 26) horses known to have been exposed to EHV1, either by infection or immunisation with EHV1, had significant levels of antibody against the EHV1 gG antigen (i.e., all horses recognised the EHV1 epitope(s) contained within this molecule). Maintenance of EHV1 gG antibody was examined by testing sera obtained from mares four years after confirmed EHV1 abortion. Seven out of 10 of these mares remained EHV1 ELISA positive. In summary, the ELISA is highly specific and is sufficiently sensitive to detect all horses previously infected with EHV4 and most previously infected with EHV1.

  3. Radiometric cytolysis inhibition assay, a new rapid test for neutralizing antibodies to intact and trypsin-cleaved poliovirus

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

    Hovi, T.; Roivainen, M.

    1989-04-01

    We have developed a new rapid test, the radiometric cytolysis inhibition assay (RACINA), for the determination of neutralizing poliovirus antibodies. HeLa cells prelabeled with /sup 51/Cr, (/sup 3/H)leucine, or, preferentially, with (/sup 3/H)uridine are used as sensitive quantitative indicators of residual infectious virus. Both suspensions and monolayer cultures of the indicator cells can be used. Neutralization of a fraction of a high-titer virus preparation can be scored after the first replication cycle at 8 to 10 h. By lowering the incubation temperature to 30/degree/C, the completion of the cytolysis due to the first replication cycle of poliovirus was delayed beyondmore » 21 h. This makes it possible to use the RACINA, unlike the standard microneutralization assay, for measuring antibodies to trypsin-cleaved polioviruses. The RACINA was found to be as sensitive as and more reproducible than the standard microneutralization assay in the measurement of neutralizing poliovirus antibodies. The RACINA is a rapid and reliable test for neutralizing antibodies and in principle it may be applicable for quantitation of neutralizing antibodies to other cytolytic agents as well.« less

  4. Interpretations of Antibody Responses to Salmonella enterica Serotype Enteritidis gm Flagellin in Poultry Flocks Are Enhanced by a Kinetics-Based Enzyme-Linked Immunosorbent Assay

    PubMed Central

    McDonough, Patrick L.; Jacobson, Richard H.; Timoney, John F.; Mutalib, Ahmed; Kradel, David C.; Chang, Yung-fu; Shin, Sang J.; Lein, Donald H.; Trock, Susan; Wheeler, Kaye

    1998-01-01

    Many regulatory and diagnostic programs for the detection of Salmonella enterica serotype Enteritidis infection in commercial poultry flocks have relied on rapid Pullorum agglutination tests to screen birds because of the shared antigens of S. enterica Enteritidis and S. enterica Pullorum and Gallinarum; however, the use of the enzyme-linked immunosorbent assay (ELISA) format affords better analytical sensitivity than crude agglutination tests. In this study, we adapted our earlier conventional indirect ELISA, using gm flagellin as the antigen, to a kinetics-based, computer-controlled ELISA (KELA). The KELA was used to screen for flagellin antibody from three commercial flocks: (i) a large flock involved in a U.S. Department of Agriculture trace back from a human S. enterica Enteritidis foodborne outbreak (n = 3,209), (ii) a flock infected with the endemic S. enterica Enteritidis serotype but which also had multiple other salmonella serotypes (n = 65), and (iii) an S. enterica Pullorum-infected flock (n = 12). The first flock (S. enterica Enteritidis prevalence of 2.45% based on culture) provided a field test of the KELA and allowed the calculation of diagnostic sensitivity (D-Sn) and diagnostic specificity (D-Sp). With a cutoff of 10 (used for screening flocks [i.e., high sensitivity]), the KELA has a D-Sn of 95.2% and a D-Sp of 18.5%; with a cutoff of 140 (used in confirmatory flock testing [i.e., high specificity]), the KELA has a D-Sn of 28.0% and a D-Sp of 99.1%. We found that with a cutoff of 60 (D-Sn = 63.1%; D-Sp = 91.6%), we could eliminate reactions in the KELA caused by other non-S. enterica Enteritidis salmonellae. The KELA was also compared to two commercial rapid Pullorum tests, the Solvay (D-Sn = 94.9%; D-Sp = 55.5%) and the Vineland (D-Sn = 62.0%; D-Sp = 75.3%). PMID:9665965

  5. A dispermic chimera was identified in a healthy man with mixed field agglutination reaction in ABO blood grouping and mosaic 46, XY/46, XX karyotype.

    PubMed

    Hong, Xiaozhen; Ying, Yanlin; Xu, Xianguo; Liu, Ying; Chen, Zhimei; Lan, Xiaofei; Ma, Kairong; He, Ji; Zhu, Faming; Lv, Hangjun; Yan, Lixing

    2013-04-01

    Chimerism is the presence of two or more genetically distinct cell populations in one organism. Here, we reported the identification of dispermic chimerism in a 25-year-old male. Blood grouping was performed with standard gel centrifugation test cards. ABO and HLA-A,-B,-C,-DRB1 and -DQB1 loci genotyping was determined with PCR sequence-based typing. A quantitative analysis of dual red cells populations was measured by flow cytometer. The karyotype was analyzed by G-banded chromosomes. Short tandem repeat (STR) analysis was performed on blood, buccal mucosal and hair shafts samples. A mixed-field agglutination with anti-B antibody was observed with gel centrifugation tests, which showed a double populations of O and B groups RBCs. Two groups RBCs were also observed by flow cytometer with nearly 90% O group cells and 10% B group cells. The normal O01,O02,B101 alleles were identified in DNA sample of the proband. STR analysis revealed three alleles for D8S1179,D3S1358,TH01,D13S317,D16S539,D2S1338,D19S433,TPOX and D18S51 loci. HLA-DRB1 and -DQB1 loci had three alleles and a karyotypic mosaic was found with 60% 46, XY and 40% 46, XX karyotype in the proband. In all studies, the third allele was attributable to a dual paternal contribution. A individual with dispermic chimerism was identified, which would generate by fertilization of an oocyte and the corresponding second polar body by two different sperms. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Evaluation of formalin-inactivated Clostridium difficile vaccines administered by parenteral and mucosal routes of immunization in hamsters.

    PubMed Central

    Torres, J F; Lyerly, D M; Hill, J E; Monath, T P

    1995-01-01

    Clostridium difficile produces toxins that cause inflammation, necrosis, and fluid in the intestine and is the most important cause of nosocomial antibiotic-associated diarrhea and colitis. We evaluated C. difficile antigens as vaccines to protect against systemic and intestinal disease in a hamster model of clindamycin colitis. Formalin-inactivated culture filtrates from a highly toxigenic strain were administered by mucosal routes (intranasal, intragastric, and rectal) with cholera toxin as a mucosal adjuvant. A preparation of culture filtrate and killed whole cells was also tested rectally. The toxoid was also tested parenterally (subcutaneously and intraperitoneally) and by a combination of three intranasal immunizations followed by a combined intranasal-intraperitoneal boost. Serum antibodies against toxins A and B and whole-cell antigen were measured by enzyme-linked immunosorbent assay, neutralization of cytotoxic activity, and bacterial agglutination. The two rectal immunization regimens induced low antibody responses and protected only 20% of hamsters against death and 0% against diarrhea. The intragastric regimen induced high antibody responses but low protection, 40% against death and 0% against diarrhea. Hamsters immunized by the intranasal, intraperitoneal, and subcutaneous routes were 100% protected against death and partially protected (40, 40, and 20%, respectively) against diarrhea. Among the latter groups, intraperitoneally immunized animals had the highest serum anticytotoxic activity and the highest agglutinating antibody responses. Hamsters immunized intranasally and revaccinated intraperitoneally were 100% protected against both death and diarrhea. Protection against death and diarrhea correlated with antibody responses to all antigens tested. The results indicate that optimal protection against C. difficile disease can be achieved with combined parenteral and mucosal immunization. PMID:7591115

  7. Autoantibodies to the Rpp25 component of the Th/To complex are the most common antibodies in patients with systemic sclerosis without antibodies detectable by widely available commercial tests.

    PubMed

    Mahler, Michael; Satoh, Minoru; Hudson, Marie; Baron, Murray; Chan, Jason Y F; Chan, Edward K L; Wick, James; Fritzler, Marvin J

    2014-07-01

    Antinuclear antibodies (ANA) occur in up to 95% of patients with systemic sclerosis (SSc). In most, SSc-associated antibodies are detected (i.e., centromere, topoisomerase I, RNA polymerase III, PM/Scl, Ro52/TRIM21, and U1RNP). Ribonuclease P protein subunit p25, (Rpp25) is an autoantigenic component of the Th/To complex. The contribution of anti-Th/To and anti-Rpp25 antibodies to ANA positivity in patients with SSc remains unknown. Sera from 873 patients with SSc were tested for ANA, and SSc-associated antibodies were measured. Samples without antibodies to extractable nuclear antigens (ENA; n = 53, ANA+/ENA-), were analyzed by immunoprecipitation (IP) and metabolically labeled proteins and for anti-Rpp25 antibodies (n = 50) by a chemiluminescent immunoassay (CLIA) and Rpp25 ELISA. Anti-Th/To antibodies occurred in 19/53 (36%), as determined by IP, and were the most common autoantibody in ANA+/ENA- SSc. Of those samples, 50/53 were available for additional testing by CLIA and ELISA. Anti-Rpp25 antibodies were detected in 12 (24% CLIA) or 10 (20% ELISA) of 50 patients. Receiver-operating characteristic curve analysis showed similar discrimination between Th/To IP-positive (n = 19) and -negative samples (n = 31) by CLIA and ELISA (area under the curve 0.90 vs 0.87; p = 0.6691). The positive percent agreement between IP and CLIA or ELISA was 12/19 (63.2%, 95% CI 38.4-83.7%) or 10/19 (52.6%, 95% CI 73.3-94.2%), respectively. Negative percent agreement was 100% for both assays. Autoantibodies to the Th/To autoantigen are important in patients with SSc who have been considered negative for SSc-specific or SSc-associated antibodies by widely available commercial assays. Rpp25 can be considered a major target of anti-Th/To antibodies. Assays detecting anti-Th/To and anti-Rpp25 antibodies may be important in SSc.

  8. Field comparison of OraQuick® ADVANCE Rapid HIV-1/2 antibody test and two blood-based rapid HIV antibody tests in Zambia

    PubMed Central

    2012-01-01

    Background Zambia’s national HIV testing algorithm specifies use of two rapid blood based antibody assays, Determine®HIV-1/2 (Inverness Medical) and if positive then Uni-GoldTM Recombigen HIV-1/2 (Trinity Biotech). Little is known about the performance of oral fluid based HIV testing in Zambia. The aims of this study are two-fold: 1) to compare the diagnostic accuracy (sensitivity and specificity) under field conditions of the OraQuick® ADVANCE® Rapid HIV-1/2 (OraSure Technologies, Inc.) to two blood-based rapid antibody tests currently in use in the Zambia National Algorithm, and 2) to perform a cost analysis of large-scale field testing employing the OraQuick®. Methods This was a operational retrospective research of HIV testing and questionnaire data collected in 2010 as part of the ZAMSTAR (Zambia South Africa TB and AIDS reduction) study. Randomly sampled individuals in twelve communities were tested consecutively with OraQuick® test using oral fluid versus two blood-based rapid HIV tests, Determine® and Uni-GoldTM. A cost analysis of four algorithms from health systems perspective were performed: 1) Determine® and if positive, then Uni-GoldTM (Determine®/Uni-GoldTM); based on current algorithm, 2) Determine® and if positive, then OraQuick® (Determine®/OraQuick®), 3) OraQuick® and if positive, then Determine® (OraQuick®/Determine®), 4) OraQuick® and if positive, then Uni-GoldTM (OraQuick®/Uni-GoldTM). This information was then used to construct a model using a hypothetical population of 5,000 persons with varying prevalence of HIV infection from 1–30%. Results 4,458 participants received both a Determine® and OraQuick® test. The sensitivity and specificity of the OraQuick® test were 98.7 (95%CI, 97.5–99.4) and 99.8 (95%CI, 99.6–99.9), respectively when compared to HIV positive serostatus. The average unit costs per algorithm were US$3.76, US$4.03, US$7.35, and US$7.67 for Determine®/Uni-GoldTM, Determine®/OraQuick®, Ora

  9. Seroprevalence of Toxoplasma gondii infection in domestic pigs in Durango State, Mexico

    USDA-ARS?s Scientific Manuscript database

    Little is known concerning the prevalence of Toxoplasma gondii infection in pigs in Mexico. Antibodies to T. gondii were determined in 1,077 domestic pigs in Durango, Mexico using the modified agglutination test (MAT). Two groups (A, B) of pigs were sampled: Group A pigs (n=555) were raised in 3 geo...

  10. Low Seroprevalence of Leishmania infantum and Toxoplasma gondii in the Horse Population in Israel.

    PubMed

    Aharonson-Raz, Karin; Baneth, Gad; Lopes, Ana Patrícia; Brancal, Hugo; Schallig, Henk; Cardoso, Luís; Steinman, Amir

    2015-12-01

    A cross-sectional investigation was done on the seroprevalence of Leishmania infantum and Toxoplasma gondii infection among apparently healthy horses in Israel. This survey included 383 horses distributed in 22 farms throughout Israel during the years 2011-2013. Serum samples were tested for the presence of immunoglobulin G (IgG) antibodies using the direct agglutination test (DAT) specific to Leishmania and by the modified agglutination test (MAT) for the presence of IgG antibodies to T. gondii. Low seroprevalences were detected for both L. infantum and T. gondii in the horse population in Israel; of the 338 horses tested, 6 (1.4%) were found to be seropositive for L. infantum and 11 (2.5%) for T. gondii, with no significant association between seroprevalence and demographic/environmental factors. An ongoing geographical expansion of L. infantum, previously reported in humans and dogs in Israel, was also supported by our results in horses. Here we present evidence of exposure of horses to L. infantum and T. gondii in Israel. Continuous seroprevalence surveillance in horses, such as the one performed in this study, might further elucidate the eco-epidemiology of these two important zoonotic parasites in this country.

  11. siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene.

    PubMed

    Minami, Kosuke; Okamoto, Koji; Doi, Kent; Harano, Koji; Noiri, Eisei; Nakamura, Eiichi

    2014-05-12

    The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications.

  12. siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene

    NASA Astrophysics Data System (ADS)

    Minami, Kosuke; Okamoto, Koji; Doi, Kent; Harano, Koji; Noiri, Eisei; Nakamura, Eiichi

    2014-05-01

    The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications.

  13. siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene

    PubMed Central

    MINAMI, Kosuke; OKAMOTO, Koji; DOI, Kent; HARANO, Koji; NOIRI, Eisei; NAKAMURA, Eiichi

    2014-01-01

    The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications. PMID:24814863

  14. Development of a serology-based assay for efficacy evaluation of a lactococcicosis vaccine in Seriola fish.

    PubMed

    Nakajima, Nao; Kawanishi, Michiko; Imamura, Saiki; Hirano, Fumiya; Uchiyama, Mariko; Yamamoto, Kinya; Nagai, Hidetaka; Futami, Kunihiko; Katagiri, Takayuki; Maita, Masashi; Kijima, Mayumi

    2014-05-01

    Lactococcicosis is an infection caused by the bacterium Lactococcus garvieae and creates serious economic damage to cultured marine and fresh water fish industries. The use of the assay currently applied to evaluate the potency of the lactococcicosis vaccine is contingent upon meeting specific parameters after statistical analysis of the percent survival of the vaccinated yellowtail or greater amberjack fish after challenge with a virulent strain of L. garvieae. We found that measuring the serological response with a quantitative agglutinating antibody against the L. garvieae antigen (phenotype KG+) was an effective method of monitoring the potency of lactococcicosis vaccines. Vaccinated fish had significantly higher antibody titers than control fish when the L. garvieae Lg2-S strain was used as an antigen. Furthermore, the titer of the KG + agglutinating antibody was correlated with vaccine potency, and the cut-off titer was determined by comparing the data with those from the challenge test. An advantage of the proposed serology-based potency assay is that it will contribute to reduced numbers of animal deaths during vaccine potency evaluations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Human anti-HIV IgM detection by the OraQuick ADVANCE® Rapid HIV 1/2 Antibody Test.

    PubMed

    Guillon, Geraldine; Yearwood, Graham; Snipes, Casey; Boschi, Daniel; Reed, Michael R

    2018-01-01

    The Centers for Disease Control and Prevention (CDC) and many public health jurisdictions continue to advocate for the most sensitive rapid HIV test that is available. Currently, the recommendation is to utilize tests that can detect HIV infection biomarkers within 30 days of infection, when initial immune responses are mounted. The infected patient's IgM response is often used to detect acute infection within a 20-25 days window after infection. This requirement applies to lab-based testing with automated analyzers and rapid, point of care (POC) testing used for screening in a non-clinical setting. A recent study has demonstrated that POC tests using a Protein A-based detection system can detect samples with predominantly HIV-1 IgM reactivity (Moshgabadi et al., 2015). The OraQuick ADVANCE ® Rapid HIV-1/2 Antibody Test (OraQuick ADVANCE ®) also uses Protein A as the detection protein in the antibody-binding colloidal gold conjugate, so it is expected that the OraQuick ADVANCE ® Test will also detect samples with predominantly IgM reactivity. This report definitively demonstrates that the OraQuick ADVANCE ® Test can detect IgM antibodies during an acute infection window period of approximately 20-25 days after infection, and is therefore suitable for use in testing environments requiring adherence to current CDC recommendations.

  16. Comparison of Rapid Point-of-Care Tests for Detection of Antibodies to Hepatitis C Virus

    PubMed Central

    Fisher, Dennis G.; Hess, Kristen L.; Erlyana, Erlyana; Reynolds, Grace L.; Cummins, Catherine A.; Alonzo, Todd A.

    2015-01-01

    Background. Hepatitis C is one of the most prevalent blood-borne diseases in the United States. Despite the benefits of early screening, among 3.2 million Americans who are infected with hepatitis C virus (HCV), 50%–70% are unaware of their infection status. Methods. Data were collected between 2011 and 2014, from 1048 clients who were in the following groups: (1) injection drug users, (2) women at sexual risk, (3) gay and bisexual men, and (4) transgender individuals. The sensitivity and specificity of point-of-care tests included (1) the MedMira rapid human immunodeficiency virus (HIV)/HCV antibody test, (2) MedMira hepatitis B (HBV)/HIV/HCV antibody test, (3) Chembio HCV Screen Assay used with both whole blood and (4) oral specimens, (5) Chembio HIV-HCV Assay also used with both whole blood and (6) oral specimens, (7) Chembio HIV-HCV-Syphilis Assay, and (8) OraSure HCV Rapid Antibody Test used with whole blood. The gold standard for the HCV tests were HCV enzyme immunoassay (EIA) 2.0. Results. OraSure had the highest sensitivity at 92.7% (95% confidence interval [CI] = 88.8%–96.5%) followed closely by Chembio's 3 blood tests at 92.1% (95% CI = 87.7%–96.4%), 91.5% (95% CI = 87.2%–95.7%), and 92.3% (95% CI = 88.4%–96.2%). The sensitivities of MedMira HIV/HCV and MedMira HIV/HCV/HBV tests were the lowest, at 79.1% (95% CI = 72.6%–85.5%), and 81.5% (95% CI = 75.2%–87.8%), respectively. Specificity for the OraSure was 99.8% (95% CI = 99.4%–100%); specificity for the Chembio blood tests was 99.2% (95% CI = 98.6%–99.9%), 99.4% (95% CI = 98.8%–99.9%), and 99.3% (95% CI = 98.8%–99.9%); and specificity for the MedMira was100% and 100%. False-negative results were associated with HIV and hepatitis B core antibody serostatus. Conclusions. The OraSure and Chembio blood tests (including those multiplexed with HIV and syphilis) appear to good performance characteristics. This study has identified potential limitations of rapid testing in those

  17. Blood Group Antigens on HeLa Cells shown by Mixed Agglutination

    PubMed Central

    Kelus, A.; Gurner, B. W.; Coombs, R. R. A.

    1959-01-01

    The mixed agglutination reaction has been used for investigating the presence of blood group antigens on the surface of human cervical carcinoma cells (HeLa) cultured for eight years in vitro. The H antigen was demonstrated in the absence of A and B. The MN-type antigen has been found as well as Tja. Treatment of HeLa cells with ficin greatly enhanced the reaction of anti-H and anti-Tja with the corresponding antigens on HeLa cells. The authors failed to show the following antigens: Rh(D) and Rh(c), S, P, Lea, Leb, Lua and Lub. ImagesFIG. 1FIG. 2 PMID:14405338

  18. Antibody profiling sensitivity through increased reporter antibody layering

    DOEpatents

    Apel, William A.; Thompson, Vicki S.

    2013-02-26

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  19. Antibody profiling sensitivity through increased reporter antibody layering

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

    Apel, William A.; Thompson, Vicki S

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immunemore » complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.« less

  20. Antibody profiling sensitivity through increased reporter antibody layering

    DOEpatents

    Apel, William A.; Thompson, Vicki S.

    2017-03-28

    A method for analyzing a biological sample by antibody profiling for identifying forensic samples or for detecting the presence of an analyte. In an embodiment of the invention, the analyte is a drug, such as marijuana, Cocaine (crystalline tropane alkaloid), methamphetamine, methyltestosterone, or mesterolone. The method comprises attaching antigens to a surface of a solid support in a preselected pattern to form an array wherein locations of the antigens are known; contacting the array with the biological sample such that a portion of antibodies in the sample reacts with and binds to the antigens in the array to form immune complexes; washing away antibodies that do form immune complexes; and detecting the immune complexes, to form an antibody profile. Forensic samples are identified by comparing a sample from an unknown source with a sample from a known source. Further, an assay, such as a test for illegal drug use, can be coupled to a test for identity such that the results of the assay can be positively correlated to the subject's identity.

  1. New monoclonal antibody-based test for Helicobacter pylori urease in gastric tissue.

    PubMed

    Kim, Do Hyun; Kim, Ho Dong; Park, Hyeuk; Choi, Seung; Beom, Jae Won; Kim, Woo Jong; Park, Chang Kook; Lee, Young Jik; Park, Ju Young; Kim, Hyung Rag; Park, Chul; Joo, Young Eun; Jung, Young Do

    2016-01-01

    To evaluate a new monoclonal antibody for Helicobacter pylori urease in gastric tissue. A total of 107 volunteers were enrolled. All subjects underwent a (13)C-urea breath test and esophagogastroduodenoscopy. Gastric aspirates were analyzed for pH and ammonia. Six biopsy specimens in the gastric antrum and body were obtained for a rapid urease test and histology. The new monoclonal antibody-based H. pylori urease test (HPU) was performed to rapidly and qualitatively detect urease in two biopsy specimens. H. pylori infection was diagnosed in 73 subjects. The sensitivity and specificity of the HPU was 89% and 74%, respectively. The subjects were divided into two groups: one with true-positive and true-negative HPU results (n = 90) and the other with false-positive and false-negative HPU results (n = 17). Across all subjects, ammonia levels were 900.5 ± 646.7 and 604.3 ± 594.3 μmol/L (p > 0.05), and pH was 3.37 ± 1.64 and 2.82 ± 1.51 (p > 0.05). Sensitivity was higher in the presence of atrophic gastritis or intestinal metaplasia. HPU detected H. pylori in approximately 10 min. Gastric aspirate ammonia and pH levels did not affect the test results. Sensitivity was good in the presence of atrophic gastritis or intestinal metaplasia.

  2. Genetic and mechanistic evaluation for the weak A phenotype in Ael blood type with IVS6 + 5G>A ABO gene mutation.

    PubMed

    Chen, D-P; Sun, C-F; Ning, H-C; Peng, C-T; Wang, W-T; Tseng, C-P

    2015-01-01

    Ael is a rare blood type that is characterized by weak agglutination of RBCs when reacts with anti-A antibody in adsorption-elution test. Although IVS6 + 5G→A mutation is known to associate with the Ael blood type, genetic and mechanistic evaluation for the weak agglutination of Ael with IVS6 + 5G→A mutation has not yet been completely addressed. In this study, five cases of confirmed Ael individuals were analysed. The cDNAs for the A(el) alleles were obtained by cloning method for sequence analyses. The erythroleukemia K562 cells were used as the cell study model and were transfected with the A(el) expression construct. Flow cytometry analysis was then performed to determine the levels of surface antigen expression. The results indicated that IVS6 + 5G→A attributes to all cases of Ael . RT-PCR analyses revealed the presence of at least 10 types of aberrant A(el) splicing transcripts. Most of the transcripts caused early termination and produced non-functional protein during translation. Nevertheless, the transcript without exons 5-6 was predicted to generate functional Ael glycosyltransferase lacking 57 amino acids at the N-terminal segment. When the exons 5-6 deletion transcript was stably expressed in the K562 cells, weak agglutination of the cells can be induced by adding anti-A antibody followed by adsorption-elution test. This study demonstrates that aberrant splicing of A transcripts contributes to weak A expression and the weak agglutination of Ael -RBCs, adding to the complexity for the regulatory mechanisms of ABO gene expression. © 2014 International Society of Blood Transfusion.

  3. Pseudo-plaque reduction neutralization test (PPRNT) for the measurement of neutralizing antibodies to Crimean-Congo hemorrhagic fever virus.

    PubMed

    Canakoglu, Nurettin; Berber, Engin; Ertek, Mustafa; Yoruk, Mustafa D; Tonbak, Sukru; Bolat, Yusuf; Aktas, Munir; Kalkan, Ahmet; Ozdarendeli, Aykut

    2013-01-03

    Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV. Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies. Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed. The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the measurement of CCHF neutralizing antibodies

  4. Pseudo-plaque reduction neutralization test (PPRNT) for the measurement of neutralizing antibodies to Crimean-Congo hemorrhagic fever virus

    PubMed Central

    2013-01-01

    Background Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus of the genus Nairovirus family Bunyaviridae, which are enveloped viruses containing tripartite, negative polarity, single-stranded RNA. CCHF is characterized by high case mortality, occurring in Asia, Africa, the Middle East and Europe. Currently, there are no specific treatments or licensed vaccines available for CCHFV. Recently, two research groups have found adult mice with defective interferon responses allowed to lethal CCHFV infection. These mouse models could provide invaluable information for further studies. Efforts to develop a vaccine against CCHFV are being made. To determine the efficacy of vaccine candidates it is important to conduct serological studies that can accurately measure levels of protective antibodies. In the present study, a pseudo-plaque reduction neutralization test (PPRNT) based on enzyme-catalyzed color development of infected cells probed with anti-CCHFV antibodies was used to measure neutralization antibody of CCHFV. Methods Sixty-nine human serum samples (20 acute and 49 convalescent) were tested. The presence of CCHFV antibodies was determined and confirmed by a commercial ELISA kit. CCHFV RNA was determined by RT-PCR. All the samples were analyzed by PPRNT and fluorescent focus reduction neutralization test (FFRNT) to measure of CCHFV-neutralizing antibodies. Results Pseudo-plaque reduction neutralization test showed a high sensitivity (98%), specificity (100%) and agreement (96,6%) in qualitative comparison with those of the FFRNT. There was a high correlation between the titers obtained in PPRNT and FFRNT (R2 = 0.92). The inter- and intra-assay variation of PPRNT revealed good reproducibility and positive cut-off of PPRNT was defined as 1:4 by the geometric mean titers for the individual samples distributed. Conclusion The pseudo-plaque reduction neutralization test described in this study is a fast, reproducible and sensitive method for the

  5. Cost-effectiveness of Chlamydia antibody tests in subfertile women.

    PubMed

    Fiddelers, A A A; Land, J A; Voss, G; Kessels, A G H; Severens, J L

    2005-02-01

    For the evaluation of tubal function, Chlamydia antibody testing (CAT) has been introduced as a screening test. We compared six CAT screening strategies (five CAT tests and one combination of tests), with respect to their cost-effectiveness, by using IVF pregnancy rate as outcome measure. A decision analytic model was developed based on a source population of 1715 subfertile women. The model incorporates hysterosalpingography (HSG), laparoscopy and IVF. To calculate IVF pregnancy rates, costs, effects, cost-effectiveness and incremental costs per effect of the six different CAT screening strategies were determined. pELISA Medac turned out to be the most cost-effective CAT screening strategy (15 075 per IVF pregnancy), followed by MIF Anilabsystems (15 108). A combination of tests (pELISA Medac and MIF Anilabsystems; 15 127) did not improve the cost-effectiveness of the single strategies. Sensitivity analyses showed that the results are robust for changes in the baseline values of the model parameters. Only small differences were found between the screening strategies regarding the cost-effectiveness, although pELISA Medac was the most cost-effective strategy. Before introducing a particular CAT test into clinical practice, one should consider the effects and consequences of the entire screening strategy, instead of only the diagnostic accuracy of the test used.

  6. Production of a Recombinant Antibody Specific for i Blood Group Antigen, a Mesenchymal Stem Cell Marker

    PubMed Central

    Suila, Heli; Tiitinen, Sari; Natunen, Suvi; Laukkanen, Marja-Leena; Kotovuori, Annika; Reinman, Mirka; Satomaa, Tero; Alfthan, Kaija; Laitinen, Saara; Takkinen, Kristiina; Räbinä, Jarkko; Valmu, Leena

    2013-01-01

    Abstract Multipotent mesenchymal stem/stromal cells (MSCs) offer great promise for future regenerative and anti-inflammatory therapies. Panels of functional and phenotypical markers are currently used in characterization of different therapeutic stem cell populations from various sources. The i antigen (linear poly-N-acetyllactosamine) from the Ii blood group system has been suggested as a marker for MSCs derived from umbilical cord blood (UCB). However, there are currently no commercially available antibodies recognizing the i antigen. In the present study, we describe the use of antibody phage display technology to produce recombinant antibodies recognizing a structure from the surface of mesenchymal stem cells. We constructed IgM phage display libraries from the lymphocytes of a donor with an elevated serum anti-i titer. Antibody phage display technology is not dependent on immunization and thus allows the generation of antibodies against poorly immunogenic molecules, such as carbohydrates. Agglutination assays utilizing i antigen–positive red blood cells (RBCs) from UCB revealed six promising single-chain variable fragment (scFv) antibodies, three of which recognized epitopes from the surface of UCB-MSCs in flow cytometric assays. The amino acid sequence of the VH gene segment of B12.2 scFv was highly similar to the VH4.21 gene segment required to encode anti-i specificities. Further characterization of binding properties revealed that the binding of B12.2 hyperphage was inhibited by soluble linear lactosamine oligosaccharide. Based on these findings, we suggest that the B12.2 scFv we have generated is a prominent anti-i antibody that recognizes i antigen on the surface of both UCB-MSCs and RBCs. This binder can thus be utilized in UCB-MSC detection and isolation as well as in blood group serology. PMID:24083089

  7. Occurrence of Shiga toxin-producing Escherichia coli O157 in selected dairy and meat products marketed in the city of Rabat, Morocco.

    PubMed

    Benkerroum, N; Bouhlal, Y; El Attar, A; Marhaben, A

    2004-06-01

    Samples of meat and dairy products taken from the city of Rabat, Morocco, were examined for the presence of Escherichia coli O157 by the selective enrichment procedure followed by plating on cefixime-tellurite-sorbitol MacConkey agar and a latex agglutination test. The ability of isolates to produce Shiga toxins (ST1 or ST2) was also tested by an agglutination test using sensitized latex. Dairy samples (n = 44) included different products commonly consumed in the country. Meat samples (n = 36) were taken from traditional butchers because these products are generally marketed in this way. Random samples were taken from each product during the period of January through May. Of the 80 samples tested, 8 (10%) harbored E. coli O157. Four dairy and four meat samples were contaminated (9.1 and 11.1%, respectively). Of 10 E. coli O157 isolates from contaminated samples demonstrating true antigen-antibody agglutination, 5 (50%) produced either ST2 alone or ST2 plus ST1. Four of the five strains (80%) were meat isolates and produced ST2 with or without ST1, and the fifth was a dairy isolate producing ST2.

  8. Associations among immunological, parasitological and clinical parameters in canine visceral leishmaniasis: Emaciation, spleen parasitism, specific antibodies and leishmanin skin test reaction.

    PubMed

    Dos-Santos, W L C; Jesus, E E; Paranhos-Silva, M; Pereira, A M; Santos, J C; Baleeiro, C O; Nascimento, E G; Moreira, E D; Oliveira, G G S; Pontes-de-Carvalho, L C

    2008-06-15

    Associations among parameters commonly used as markers of infection by Leishmania sp., or of susceptibility to visceral leishmaniasis, were investigated in 325 stray dogs from an area where this disease is endemic. Evidence of infection (presence of Leishmania in splenic cultures, positive leishmanin skin test (LST) or detection of anti-Leishmania antibody activity in the serum) was found in 57% of the animals. Both evidence of weight loss (chi(2)-test, P=0.0005) and presence of specific antibody activity in the serum (chi(2)-test, P<0.0001) were directly associated with positive splenic culture. The frequencies of animals with positive splenic culture were directly correlated with the intensities of antibody activity in the serum as measured by ELISA (relative risk of 3.4 for animals with moderate antibody levels and relative risk of 8.43 for animals with high-antibody levels). A negative association was observed between positive leishmanin skin test results and emaciation (chi(2), P=0.0089). Furthermore, animals with positive splenic cultures and negative leishmanin skin test results had higher levels of total serum IgG (Kruskal-Wallis test, P=0.001) and IgG2 (Kruskal-Wallis test, P=0.05) than animals with negative splenic cultures, and were more emaciated than animals with negative LST results and positive splenic cultures. The data presented herein suggest that associating these common parameters may improve their performance in predicting susceptibility to canine visceral leishmaniasis.

  9. Assessment of pathogenesis of infective endocarditis by plasma IgG antibody titer test against periodontal bacteria.

    PubMed

    Isoshima, Daichi; Yamashiro, Keisuke; Matsunaga, Kazuyuki; Shinobe, Michitaka; Nakanishi, Nagako; Nakanishi, Izumi; Omori, Kazuhiro; Yamamoto, Tadashi; Takashiba, Shogo

    2017-10-01

    Oral bacteria cause infective endocarditis (IE), so severe periodontitis is thought to be high risk for IE. We suggest the identification of high-risk patients by an IgG antibody titer test against periodontal bacteria might become common screening test.

  10. Effect of Irradiation and Test System on Development of Tetanus Antibodies

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

    Benenson, A. S.; Shively, J. N.; Vivona, S.

    1963-03-01

    Whole-body irradiation of dogs immunized with an alum precipitated tetanus toxoid results in a delay in appearance of antitoxin of the first toxoid us administered after radiation. Dogs irradiated 30 days after a first dose of toxoid and receiving a booster injection 24 hours after irradiation presented a good antitoxin response when measured by the hemagglutination test. However, a poor antibody response was found if the antitoxin was measured by the toxin neutralization techniques.

  11. Impact of Uniform Methods on Interlaboratory Antibody Titration Variability: Antibody Titration and Uniform Methods.

    PubMed

    Bachegowda, Lohith S; Cheng, Yan H; Long, Thomas; Shaz, Beth H

    2017-01-01

    -Substantial variability between different antibody titration methods prompted development and introduction of uniform methods in 2008. -To determine whether uniform methods consistently decrease interlaboratory variation in proficiency testing. -Proficiency testing data for antibody titration between 2009 and 2013 were obtained from the College of American Pathologists. Each laboratory was supplied plasma and red cells to determine anti-A and anti-D antibody titers by their standard method: gel or tube by uniform or other methods at different testing phases (immediate spin and/or room temperature [anti-A], and/or anti-human globulin [AHG: anti-A and anti-D]) with different additives. Interlaboratory variations were compared by analyzing the distribution of titer results by method and phase. -A median of 574 and 1100 responses were reported for anti-A and anti-D antibody titers, respectively, during a 5-year period. The 3 most frequent (median) methods performed for anti-A antibody were uniform tube room temperature (147.5; range, 119-159), uniform tube AHG (143.5; range, 134-150), and other tube AHG (97; range, 82-116); for anti-D antibody, the methods were other tube (451; range, 431-465), uniform tube (404; range, 382-462), and uniform gel (137; range, 121-153). Of the larger reported methods, uniform gel AHG phase for anti-A and anti-D antibodies had the most participants with the same result (mode). For anti-A antibody, 0 of 8 (uniform versus other tube room temperature) and 1 of 8 (uniform versus other tube AHG), and for anti-D antibody, 0 of 8 (uniform versus other tube) and 0 of 8 (uniform versus other gel) proficiency tests showed significant titer variability reduction. -Uniform methods harmonize laboratory techniques but rarely reduce interlaboratory titer variance in comparison with other methods.

  12. Receiver operating characteristic analysis of prediction for gastric cancer development using serum pepsinogen and Helicobacter pylori antibody tests.

    PubMed

    Hamashima, Chisato; Sasazuki, Shizuka; Inoue, Manami; Tsugane, Shoichiro

    2017-03-09

    Chronic Helicobacter pylori infection plays a central role in the development of gastric cancer as shown by biological and epidemiological studies. The H. pylori antibody and serum pepsinogen (PG) tests have been anticipated to predict gastric cancer development. We determined the predictive sensitivity and specificity of gastric cancer development using these tests. Receiver operating characteristic analysis was performed, and areas under the curve were estimated. The predictive sensitivity and specificity of gastric cancer development were compared among single tests and combined methods using serum pepsinogen and H. pylori antibody tests. From a large-scale population-based cohort of over 100,000 subjects followed between 1990 and 2004, 497 gastric cancer subjects and 497 matched healthy controls were chosen. The predictive sensitivity and specificity were low in all single tests and combination methods. The highest predictive sensitivity and specificity were obtained for the serum PG I/II ratio. The optimal PG I/II cut-off values were 2.5 and 3.0. At a PG I/II cut-off value of 3.0, the sensitivity was 86.9% and the specificity was 39.8%. Even if three biomarkers were combined, the sensitivity was 97.2% and the specificity was 21.1% when the cut-off values were 3.0 for PG I/II, 70 ng/mL for PG I, and 10.0 U/mL for H. pylori antibody. The predictive accuracy of gastric cancer development was low with the serum pepsinogen and H. pylori antibody tests even if these tests were combined. To adopt these biomarkers for gastric cancer screening, a high specificity is required. When these tests are adopted for gastric cancer screening, they should be carefully interpreted with a clear understanding of their limitations.

  13. Serological diagnosis of neurobrucellosis.

    PubMed Central

    Sanchez-Sousa, A; Torres, C; Campello, M G; Garcia, C; Parras, F; Cercenado, E; Baquero, F

    1990-01-01

    The presence of antibodies was determined in the serum and cerebrospinal fluid in six patients with neurobrucellosis using the Rose Bengal test, the microdilution agglutination test, and the Coombs' test. Four of the patients were followed up for more than three months. The Rose Bengal test and the microagglutination test were positive in cerebrospinal fluid in five of the six cases at some stage. The Coombs' test was positive in cerebrospinal fluid in every patient and in one was the only positive serological test. Cerebrospinal fluid positivity is not excluded by low titres or negative results of antibodies in the serum for any of the three methods. A Coombs' test or some equivalent must always be made on the cerebrospinal fluid to diagnose neurobrucellosis. PMID:2312754

  14. GENETIC ANALYSIS OF THE AGGA LOCUS INVOLVED IN AGGLUTINATION ND ADHERENCE OF PSEUDOMONAS PUTIDA, A BENEFICIAL FLUORESCENT PSEUDOMONAD

    EPA Science Inventory

    An isolate of Pseudomonas putida, which rapidly adheres to plant roots is agglutinated by a glycoprotein from root surfaces. gglutination is presented and adherence to the root surface is diminished by Tn5 insertion in mutant 5123. wo cosmid clones from wild type P putida and 2.7...

  15. M-cholinoreactivity of erythrocytes of non-pregnant and pregnant women evaluated by changes in the rate of erythrocyte agglutination under the influence of acetylcholine.

    PubMed

    Strelnikova, A I; Tsirkin, V I; Krysova, A V; Hlybova, S V; Dmitrieva, S L

    2012-12-01

    Acetylcholine (5.5×10(-10)-5.5×10(-6)M) accelerated erythrocyte agglutination in men, non-pregnant women in follicular phase of the menstrual cycle, and pregnant women in the first trimester. The effect was blocked with atropine (5.5×10(-6)M). Acetylcholine had no effect on the rate of erythrocyte agglutination in non-pregnant women in the luteal phase and pregnant women in the second and third trimesters, which coincided with the development of myometrium refractoriness to acetylcholine in pregnant women. The results indicate that erythrocytes can reflect M-cholinoreactivity of internal organs.

  16. An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of Apollo 11 and 16 soils

    NASA Technical Reports Server (NTRS)

    Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

    1986-01-01

    Mixtures of chemically contrasting lunar soils have been shocked at pressures ranging from 18.2-62.0 GPa. Other than the generation of impact melts, modal and textural changes caused by shock include destruction of pore space and fused soil clasts and conversion of plagioclase to maskelynite. The loss of the fused soil component in these runs indicates that low agglutinate contents in shocked and/or compacted regolith breccias cannot be considered by themselves to be evidence of formation from immature regolith. From the petrographic and chemical data it appears that the impact glass formed mainly from the fine fraction and the fused soil component in the target, with relatively minor contributions from the other coarse clasts. The impact glasses exhibit the same chemical enrichments and depletions as their corresponding fine fractions and plot on or near a mixing line between the bulk and fine fraction of the soil in which they were formed. From this as well as several other studies it appears that the fusion of the finest fraction model is valid and that it accurately predicts the chemical systematics of impact glass formed from lunar soil. In addition, fusion of agglutinates present in the target soil is an important process.

  17. A comparison of standard serological tests for the diagnosis of bovine brucellosis in Canada.

    PubMed Central

    Stemshorn, B W; Forbes, L B; Eaglesome, M D; Nielsen, K H; Robertson, F J; Samagh, B S

    1985-01-01

    Six agglutination and two complement fixation tests were compared with respect to specificity, sensitivity and relative sensitivity for the serodiagnosis of bovine brucellosis. Based on 1051 sera from brucellosis free herds, the specificity of the tests was 98.9% for the buffered plate antigen test (BPAT), 99.2% and 99.3% for the standard tube and plate agglutination tests (STAT and SPAT), respectively, and 99.8% for the 2-mercaptoethanol test (2MET). On this small sample, the rose bengal plate test (RBPT), card test (CARD) and the complement fixation test (CFT) correctly classed all sera as negative. On a sample of 167 culture positive cattle, the sensitivities of the tests were CFT: 79.0%, BPAT: 75.4, RBPT: 74.9%, CARD: 74.3%, SPAT: 73.1%, STAT: 68.9%, and 2MET: 59.9%. All tests combined detected only 82% of these infected cattle. Analysis of the relative sensitivity of the six agglutination tests gave the following ranking: BPAT greater than RBPT greater than CARD greater than SPAT greater than STAT. The 2MET ranked between the BPAT and RBPT or between the RBPT and CARD depending on the analysis used. The use of the BPAT as a screening test is recommended provided that a test of high specificity and sensitivity such as the CFT is used to confirm screening test reactions. PMID:4075239

  18. [Differentiation of nonspecific serological reactions in brucellosis].

    PubMed

    Khristoforov, L

    1979-01-01

    Differentiation of non-specific agglutination was performed by the complement binding reaction, Coombs' reaction, Hajdu reaction, the surface fixation and agglutination reaction and the reaction of complement binding with heterologic antigens. For that purpose the following were used: 1) Serums--antiglobulin against cattle globulin, 5720 serum of various animals which had manifested non-specific agglutination with brucella antigen and brucella serums of experimentally infected sheep, of naturally infected swine and of cattle--received from abroad. 2) Antigens--of Br. abortus 99, of bacteria heterologic to brucellae: Proteus vulgaris, Listeria monocytogenes, Staphylococcus albus, Escherichia coli, Streptococcus pyogenes, S. abortus ovis, for O and OH agglutination, water extraction antigens--for complement binding and concentrated suspensions of all bacteria used in brucellose and non-brucellose serum absorption. Highest number of non-specific reactions were observed in cattle serums and lowest--in goat serums. Titers with heterologic antigens were higher than these with brucella antigens. Often the serum having non-specific agglutiantion reacted not only with one, but with more heterologic antigens. Non-specific complement binding reactions were not produced in complete antibodies with the brucella antigen. Heterologic brucella antigens were exhausted more fully than heterologic complement binding antibodies. In their effectiveness (differentiation of non-specific agglutination with brucella antigen in cattle serum) the serological reactions studied rank as follows: complement binding reaction, slow agglutination with serums absorbed by heterologic antigens, surface fixation reaction, Coombs' reaction, and Hadju agglutination.

  19. Short preheating at 41°C leads to a red blood cells count comparable to that in RET channel of Sysmex analysers in samples showing cold agglutination.

    PubMed

    La Gioia, Antonio; Fumi, Maurizio; Fiorini, Fabiana; Pezzati, Paola; Balboni, Fiamma; Bombara, Maria; Marini, Alessandra; Pancione, Ylenia; Solarino, Leonardo; Marchese, Elisa; Sale, Silvia; Rocco, Vincenzo; Fiorini, Marcello

    2018-03-13

    The presence of cold agglutinin in blood samples can cause a spontaneous agglutination of red blood cells (RBCs) when low temperature occurs. This phenomenon causes a spurious lowering of RBC count on the automated haematological analysers that are detected by incongruous values (≥370 g/L) of the mean cellular haemoglobi concentration (MCHC). A preheating at 37°C can remove the RBC agglutination generally resulting in a reliable count. It has been reported that the same result can be reached by using the optical reticulocyte (RET) channel of Sysmex analysers where the RBC count is not influenced by the presence of cold agglutinin. This study aims to evaluate these data in a larger population, with regard to environmental conditions on Sysmex analysers. We have also evaluated the influence of different thermal pretreatments on the RBC count. This study was performed on 96 remnants of peripheral blood samples (48 with MCHC in normal range and 48 with MCHC > 370 g/L) which have been analysed in different preanalytical conditions on the Sysmex analysers. A preheating of samples at 41°C for 1 min leads to a reversibility of the cold agglutination comparable to the one observed in the RET channel and yields better results compared with 37°C for 2 hours. None of described procedures assure the complete cold agglutination reversibility in every case. Consequently, since the haematological analysers not yet provide reliable parameters to confirm the complete resolution of agglutination, further verification of RBC count accuracy needs to be performed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Can Biomarkers Help Target Maturity-Onset Diabetes of the Young Genetic Testing in Antibody-Negative Diabetes?

    PubMed

    Majidi, Shideh; Fouts, Alexandra; Pyle, Laura; Chambers, Christina; Armstrong, Taylor; Wang, Zhenyuan; Batish, Sat Dev; Klingensmith, Georgeanna; Steck, Andrea K

    2018-02-01

    Maturity-onset diabetes of the young (MODY) is an antibody-negative, autosomal dominant form of diabetes. With the increasing prevalence of diabetes and the expense of MODY testing, markers to identify those who need further genetic testing would be beneficial. We investigated whether HLA genotypes, random C-peptide, and/or high-sensitivity C-reactive protein (hsCRP) levels could be helpful biomarkers for identifying MODY in antibody-negative diabetes. Subjects (N = 97) with diabetes onset ≤age 25, measurable C-peptide (≥0.1 ng/mL), and negative for all four diabetes autoantibodies were enrolled at a large academic center and tested for MODY 1-5 through Athena Diagnostics. A total of 22 subjects had a positive or very likely pathogenic mutation for MODY. Random C-peptide levels were significantly different between MODY-positive and MODY-negative subjects (0.16 nmol/L vs. 0.02 nmol/L; P = 0.02). After adjusting for age and diabetes duration, hsCRP levels were significantly lower in MODY-positive subjects (0.37 mg/L vs. 0.87 mg/L; P = 0.02). Random C-peptide level ≥0.15 nmol/L obtained at ≥6 months after diagnosis had 83% sensitivity for diagnosis of MODY with a negative predictive value of 96%. Receiver operating characteristic curves showed that area under the curve for random C-peptide (0.75) was significantly better than hsCRP (0.54), high-risk HLA DR3/4-DQB1*0302 (0.59), and high-risk HLA/random C-peptide combined (0.54; P = 0.03). Random C-peptide obtained at ≥6 months after diagnosis can be a useful biomarker to identify antibody-negative individuals who need further genetic testing for MODY, whereas hsCRP and HLA do not appear to improve this antibody/C-peptide-based approach.