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Sample records for acquired protective immunity

  1. Protection against hepatitis E virus infection by naturally acquired and vaccine-induced immunity.

    PubMed

    Zhang, J; Zhang, X-F; Zhou, C; Wang, Z-Z; Huang, S-J; Yao, X; Liang, Z-L; Wu, T; Li, J-X; Yan, Q; Yang, C-L; Jiang, H-M; Huang, H-J; Xian, Y-L; Shih, J W-K; Ng, M-H; Li, Y-M; Wang, J-Z; Zhu, F-C; Xia, N-S

    2014-06-01

    Immunity acquired from infection or vaccination protects humans from symptomatic hepatitis E. However, whether the risk of hepatitis E virus (HEV) infection is reduced by the immunity remains unknown. To understand this issue, a cohort with 12 409 participants randomized to receive the hepatitis E vaccine Hecolin(®) or placebo were serologically followed up for 2 years after vaccination. About half (47%) of participants were initially seropositive. A total of 139 infection episodes, evidenced by four-fold or greater rise of anti-HEV level or positive seroconversion, occurred in participants who received three doses of treatment. Risk of infection was highest among the baseline seronegative placebo group participants (2.04%). Pre-existing immunity and vaccine-induced immunity lower the risk significantly, to 0.52% and 0.30%, respectively. In conclusion, both vaccine-induced and naturally acquired immunity can effectively protect against HEV infection. PMID:24118636

  2. Outer Surface Protein A Protects Lyme Disease Spirochetes from Acquired Host Immunity in the Tick Vector▿

    PubMed Central

    Battisti, James M.; Bono, James L.; Rosa, Patricia A.; Schrumpf, Merry E.; Schwan, Tom G.; Policastro, Paul F.

    2008-01-01

    The Lyme disease spirochete Borrelia burgdorferi alters the expression of outer surface protein (osp) genes as the bacterium cycles between ticks and mammals. OspA is produced as borreliae enter the tick vector and remains a major surface antigen during midgut colonization. To elucidate the role of OspA in the vector, we created an insertional deletion of ospA in strain B31-A3. The ospA mutant infects mice when it is injected intradermally and is acquired by larval ticks fed on these mice, where it persists through the molt to the nymph stage. Bacterial survival rates in artificially infected tick larvae fed on naïve mice were compared with those in the vector fed on immune mice. The ospA mutant proliferates in larvae if it is exposed to blood from naïve mice, but it declines in density after larval feeding if the blood is from immune mice. When uninfected larvae are fed on B-cell-deficient mice infected with the ospA mutant, larvae show borrelial densities and persistence that are significantly greater than those fed on infected, immunocompetent mice. We conclude that OspA serves a critical antibody-shielding role during vector blood meal uptake from immune hosts and is not required for persistence in the tick vector. PMID:18779341

  3. In vivo treatment with interleukin 12 protects mice from immune abnormalities observed during murine acquired immunodeficiency syndrome (MAIDS)

    PubMed Central

    1994-01-01

    Lymphoproliferation, chronic B cell activation resulting in hypergammaglobulinemia, and profound immunodeficiency are prominent features of a retrovirus-induced syndrome designated murine acquired immunodeficiency syndrome (MAIDS). In vivo treatment of infected mice with recombinant interleukin 12 (IL-12) beginning at the time of infection or up to 9 wk after virus inoculation markedly inhibited the development of splenomegaly and lymphadenopathy, as well as B cell activation and Ig secretion. Treatment with IL-12 also had major effects in preventing induction of several immune defects including impaired production of interferon gamma (IFN-gamma) and IL-2 and depressed proliferative responses to various stimuli. The therapeutic effects of IL-12 on the immune system of mice with MAIDS were also associated with reduced expression of the retrovirus that causes this disease (BM5def), with lesser effects on expression of ecotropic MuLV. IL-12 treatment was not effective in IFN-gamma knockout mice or in infected mice treated simultaneously with IL-12 and anti-IFN-gamma. These results demonstrate that induction and progression of MAIDS are antagonized by IL-12 through high-level expression of IFN-gamma and may provide an experimental basis for developing treatments of retrovirus- induced immune disorders with similar immunopathogenic mechanisms. PMID:7964495

  4. CD4+ T cell-dependent acquired state of immunity that protects the brain against Cryptococcus neoformans.

    PubMed

    Hill, J O; Aguirre, K M

    1994-03-01

    In immunodeficient hosts, a failure in defense mechanisms allows Cryptococcus neoformans to establish foci of infection in the brain. Immune and nonspecific responses in the primary site of infection in the lung have been described, but those extrapulmonary defense mechanisms that can be mobilized against the yeast have received little attention. This paper describes a response expressed against yeast in the brain of immunocompetent hosts, a response that is weakened in hosts deficient in CD4+ T cells. When a small number of yeast gain access to the vasculature, for example through an i.v. injection, about 0.1% establish themselves in the brain. Normal mice but not SCID mice have the capacity to suppress the multiplication of these yeast cells. The host response is accelerated in mice that are recovering from a primary lung infection, resulting in long term survival without antibiotic chemotherapy. This response is ablated by anti-CD4 mAb treatment and CD4+ cells obtained from infected primed donors are needed to confer immunity on SCID recipients. The critical target for the anti-Cryptococcus immune response are yeast in the brain cortex. However, rather than preventing the colonization of the brain by blood-borne yeast, immunity apparently serves to restrict the growth of yeast in a small number of established foci.

  5. Acquired and innate immunity to polyaromatic hydrocarbons

    SciTech Connect

    Yusuf, Nabiha Timares, Laura; Seibert, Megan D.; Xu Hui; Elmets, Craig A.

    2007-11-01

    Polyaromatic hydrocarbons are ubiquitous environmental pollutants that are potent mutagens and carcinogens. Researchers have taken advantage of these properties to investigate the mechanisms by which chemicals cause cancer of the skin and other organs. When applied to the skin of mice, several carcinogenic polyaromatic hydrocarbons have also been shown to interact with the immune system, stimulating immune responses and resulting in the development of antigen-specific T-cell-mediated immunity. Development of cell-mediated immunity is strain-specific and is governed by Ah receptor genes and by genes located within the major histocompatibility complex. CD8{sup +} T cells are effector cells in the response, whereas CD4{sup +} T cells down-regulate immunity. Development of an immune response appears to have a protective effect since strains of mice that develop a cell-mediated immune response to carcinogenic polyaromatic hydrocarbons are less likely to develop tumors when subjected to a polyaromatic hydrocarbon skin carcinogenesis protocol than mice that fail to develop an immune response. With respect to innate immunity, TLR4-deficient C3H/HeJ mice are more susceptible to polyaromatic hydrogen skin tumorigenesis than C3H/HeN mice in which TLR4 is normal. These findings support the hypothesis that immune responses, through their interactions with chemical carcinogens, play an active role in the prevention of chemical skin carcinogenesis during the earliest stages. Efforts to augment immune responses to the chemicals that cause tumors may be a productive approach to the prevention of tumors caused by these agents.

  6. Progressive multifocal leukoencephalopathy occurring with the acquired immune deficiency syndrome.

    PubMed

    England, J D; Hsu, C Y; Garen, P D; Goust, J M; Biggs, P J

    1984-08-01

    A 33-year-old homosexual man with symptoms and signs of a focal brain process was subsequently found to have an acquired immune deficiency syndrome (AIDS) with biopsy-proven progressive multifocal leukoencephalopathy. This report reemphasizes the association of progressive multifocal leukoencephalopathy with AIDS and probably is best viewed as another example of an opportunistic CNS infection complicating deficient cell-mediated immunity. PMID:6540476

  7. Disentangling inborn and acquired immunity in human twins.

    PubMed

    Casanova, Jean-Laurent; Abel, Laurent

    2015-01-15

    The human geneticist Archibald Garrod noted in 1931 that, "It is, of necessity, no easy matter to distinguish between immunity which is inborn and that which has been acquired" (The Inborn Factors in Disease). In this issue of Cell, Brodin et al. show that the heritability of blood counts rapidly decreases with age for the lymphoid subsets responsible for adaptive immunity, unlike cells from other hematopoietic lineages.

  8. Heat shock proteins: stimulators of innate and acquired immunity.

    PubMed

    Colaco, Camilo A; Bailey, Christopher R; Walker, K Barry; Keeble, James

    2013-01-01

    Adjuvants were reintroduced into modern immunology as the dirty little secret of immunologists by Janeway and thus began the molecular definition of innate immunity. It is now clear that the binding of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs) on antigen presenting cells (APCs) activates the innate immune response and provides the host with a rapid mechanism for detecting infection by pathogens and initiates adaptive immunity. Ironically, in addition to advancing the basic science of immunology, Janeway's revelation on induction of the adaptive system has also spurred an era of rational vaccine design that exploits PRRs. Thus, defined PAMPs that bind to known PRRs are being specifically coupled to antigens to improve their immunogenicity. However, while PAMPs efficiently activate the innate immune response, they do not mediate the capture of antigen that is required to elicit the specific responses of the acquired immune system. Heat shock proteins (HSPs) are molecular chaperones that are found complexed to client polypeptides and have been studied as potential cancer vaccines. In addition to binding PRRs and activating the innate immune response, HSPs have been shown to both induce the maturation of APCs and provide chaperoned polypeptides for specific triggering of the acquired immune response.

  9. Acquired immune heterogeneity and its sources in human helminth infection

    PubMed Central

    BOURKE, C. D.; MAIZELS, R. M.; MUTAPI, F.

    2011-01-01

    SUMMARY Similarities in the immunobiology of different parasitic worm infections indicate that co-evolution of humans and helminths has shaped a common anti-helminth immune response. However, recent in vitro and immuno-epidemiological studies highlight fundamental differences and plasticity within host-helminth interactions. The ‘trade-off’ between immunity and immunopathology inherent in host immune responses occurs on a background of genetic polymorphism, variable exposure patterns and infection history. For the parasite, variation in life-cycle and antigen expression can influence the effector responses directed against them. This is particularly apparent when comparing gastrointestinal and tissue-dwelling helminths. Furthermore, insights into the impact of anti-helminthic treatment and co-infection on acquired immunity suggest that immune heterogeneity arises not from hosts and parasites in isolation, but also from the environment in which immune responses develop. Large-scale differences observed in the epidemiology of human helminthiases are a product of complex host-parasite-environment interactions which, given potential for exposure to parasite antigens in utero, can arise even before a parasite interacts with its human host. This review summarizes key differences identified in human acquired immune responses to nematode and trematode infections of public health importance and explores the factors contributing to these variations. PMID:20946693

  10. Naturally acquired immunity to sexual stage P. falciparum parasites.

    PubMed

    Stone, Will J R; Dantzler, Kathleen W; Nilsson, Sandra K; Drakeley, Chris J; Marti, Matthias; Bousema, Teun; Rijpma, Sanna R

    2016-02-01

    Gametocytes are the specialized form of Plasmodium parasites that are responsible for human-to-mosquito transmission of malaria. Transmission of gametocytes is highly effective, but represents a biomass bottleneck for the parasite that has stimulated interest in strategies targeting the transmission stages separately from those responsible for clinical disease. Studying targets of naturally acquired immunity against transmission-stage parasites may reveal opportunities for novel transmission reducing interventions, particularly the development of a transmission blocking vaccine (TBV). In this review, we summarize the current knowledge on immunity against the transmission stages of Plasmodium. This includes immune responses against epitopes on the gametocyte-infected erythrocyte surface during gametocyte development, as well as epitopes present upon gametocyte activation in the mosquito midgut. We present an analysis of historical data on transmission reducing immunity (TRI), as analysed in mosquito feeding assays, and its correlation with natural recognition of sexual stage specific proteins Pfs48/45 and Pfs230. Although high antibody titres towards either one of these proteins is associated with TRI, the presence of additional, novel targets is anticipated. In conclusion, the identification of novel gametocyte-specific targets of naturally acquired immunity against different gametocyte stages could aid in the development of potential TBV targets and ultimately an effective transmission blocking approach.

  11. The Role of Acquired Immunity in the Spread of Human Papillomavirus (HPV): Explorations with a Microsimulation Model

    PubMed Central

    Matthijsse, Suzette M.; van Rosmalen, Joost; Hontelez, Jan A. C.; Bakker, Roel; de Kok, Inge M. C. M.; van Ballegooijen, Marjolein; de Vlas, Sake J.

    2015-01-01

    Background Knowledge of the natural history of human papillomavirus (HPV), in particular the role of immunity, is crucial in estimating the (cost-) effectiveness of HPV vaccination and cervical cancer screening strategies, because naturally acquired immunity after clearing an infection may already protect part of the risk population against new HPV infections. Methods We used STDSIM, an established stochastic microsimulation model, quantified to the Netherlands. We explored different assumptions regarding the natural history of HPV-16 and HPV-18, and estimated the transmission probabilities and durations of acquired immunity necessary to reproduce age-specific prevalence. Results A model without acquired immunity cannot reproduce the age-specific patterns of HPV. Also, it is necessary to assume a high degree of individual variation in the duration of infection and acquired immunity. According to the model estimates, on average 20% of women are immune for HPV-16 and 15% for HPV-18. After an HPV-16 infection, 50% are immune for less than 1 year, whereas 20% exceed 30 years. For HPV-18, up to 12% of the individuals are immune for less than 1 year, and about 50% over 30 years. Almost half of all women will never acquire HPV-16 or HPV-18. Conclusions Acquired immunity likely plays a major role in HPV epidemiology, but its duration shows substantial variation. Combined with the lifetime risk, this explains to a large extent why many women will never develop cervical cancer. PMID:25642941

  12. Impact of acquired immunity and dose-dependent probability of illness on quantitative microbial risk assessment.

    PubMed

    Havelaar, A H; Swart, A N

    2014-10-01

    Dose-response models in microbial risk assessment consider two steps in the process ultimately leading to illness: from exposure to (asymptomatic) infection, and from infection to (symptomatic) illness. Most data and theoretical approaches are available for the exposure-infection step; the infection-illness step has received less attention. Furthermore, current microbial risk assessment models do not account for acquired immunity. These limitations may lead to biased risk estimates. We consider effects of both dose dependency of the conditional probability of illness given infection, and acquired immunity to risk estimates, and demonstrate their effects in a case study on exposure to Campylobacter jejuni. To account for acquired immunity in risk estimates, an inflation factor is proposed. The inflation factor depends on the relative rates of loss of protection over exposure. The conditional probability of illness given infection is based on a previously published model, accounting for the within-host dynamics of illness. We find that at low (average) doses, the infection-illness model has the greatest impact on risk estimates, whereas at higher (average) doses and/or increased exposure frequencies, the acquired immunity model has the greatest impact. The proposed models are strongly nonlinear, and reducing exposure is not expected to lead to a proportional decrease in risk and, under certain conditions, may even lead to an increase in risk. The impact of different dose-response models on risk estimates is particularly pronounced when introducing heterogeneity in the population exposure distribution.

  13. Salmonella infections: immune and non-immune protection with vaccines.

    PubMed

    Barrow, P A

    2007-02-01

    Salmonella enterica in poultry remains a major political issue. S. enterica serovar Enteritidis, particularly, remains a world-wide problem. Control in poultry by immunity, whether acquired or innate, is a possible means of containing the problem. Widespread usage of antibiotics has led to the emergence of multiple antibiotic-resistant bacteria. This problem has indicated an increasing requirement for effective vaccines to control this important zoonotic infection. An attempt is made in the present review to explain the relatively poor success in immunizing food animals against these non-host-specific Salmonella serotypes that usually produce food-poisoning, compared with the success obtained with the small number of serotypes that more typically produce systemic "typhoid-like" diseases. New examinations of old problems such as the carrier state and vertical transmission, observed with S. Pullorum, is generating new information of relevance to immunity. Newer methods of attenuation are being developed. Live vaccines, if administered orally, demonstrate non-specific and rapid protection against infection that is of biological and practical interest. However, from the point of view of consumer safety, there is a school of thought that considers inactivated or sub-unit vaccines to be the safest. The benefits of developing effective killed or sub-unit vaccines over the use of live vaccines are enormous. Recently, there have been significant advances in the development of adjuvants (e.g. microspheres) that are capable of potent immuno-stimulation, targeting different arms of the immune system. The exploitation of such technology in conjunction with the ongoing developments in identifying key Salmonella virulence determinants should form the next generation of Salmonella sub-unit vaccines for the control of this important group of pathogens. There are additional areas of concern associated with the use of live vaccines, particularly if these are generated by genetic

  14. Antigen-Specific Acquired Immunity in Human Brucellosis: Implications for Diagnosis, Prognosis, and Vaccine Development

    PubMed Central

    Cannella, Anthony P.; Tsolis, Renee M.; Liang, Li; Felgner, Philip L.; Saito, Mayuko; Sette, Alessandro; Gotuzzo, Eduardo; Vinetz, Joseph M.

    2012-01-01

    Brucella spp., are Gram negative bacteria that cause disease by growing within monocyte/macrophage lineage cells. Clinical manifestations of brucellosis are immune mediated, not due to bacterial virulence factors. Acquired immunity to brucellosis has been studied through observations of naturally infected hosts (cattle, goats), mouse models (mice), and human infection. Even though Brucella spp. are known for producing mechanisms that evade the immune system, cell-mediated immune responses drive the clinical manifestations of human disease after exposure to Brucella species, as high antibody responses are not associated with protective immunity. The precise mechanisms by which cell-mediated immune responses confer protection or lead to disease manifestations remain undefined. Descriptive studies of immune responses in human brucellosis show that TH1 (interferon-γ-producing T cells) are associated with dominant immune responses, findings consistent with animal studies. Whether these T cell responses are protective, or determine the different clinical responses associated with brucellosis is unknown, especially with regard to undulant fever manifestations, relapsing disease, or are associated with responses to distinct sets of Brucella spp. antigens are unknown. Few data regarding T cell responses in terms of specific recognition of Brucella spp. protein antigens and peptidic epitopes, either by CD4+ or CD8+ T cells, have been identified in human brucellosis patients. Additionally because current attenuated Brucella vaccines used in animals cause human disease, there is a true need for a recombinant protein subunit vaccine for human brucellosis, as well as for improved diagnostics in terms of prognosis and identification of unusual forms of brucellosis. This review will focus on current understandings of antigen-specific immune responses induced Brucella peptidic epitopes that has promise for yielding new insights into vaccine and diagnostics development, and for

  15. DNA image cytometry in acquired immune deficiency syndrome (AIDS).

    PubMed

    Auffermann, W; Krueger, G R; Böcking, A

    1986-03-01

    In nine cases with the acquired immune deficiency syndrome (AIDS), including four stage I cases, three stage II cases and two stage III cases, DNA image cytometry was performed on Feulgen-stained lymph node imprint smears. Diploidy was found in three cases, tetraploidy in three cases and octoploidy in two cases. Aneuploid DNA distribution patterns were not seen. The lymphoid cells showed an enormously increased proliferation rate. Two cases in stage I revealed characteristic intranuclear DNA inclusions in lymphoid cells. These results indicate that DNA image cytometry may be useful as an adjunct to surgical pathology in certain cases to assist in the differential diagnosis between AIDS and benign conditions of the lymphoid system as well as between AIDS and malignant lymphomas, which usually have aneuploid DNA patterns.

  16. Autopsy pathology in the acquired immune deficiency syndrome.

    PubMed Central

    Reichert, C. M.; O'Leary, T. J.; Levens, D. L.; Simrell, C. R.; Macher, A. M.

    1983-01-01

    The acquired immune deficiency syndrome (AIDS) is a devastating new illness which appears to be sexually and parenterally transmissible. AIDS was first described in the male homosexual community; however, the disease has more recently been described among intravenous drug abusers, Haitians, hemophiliacs, and others. The etiologic agent is unknown. AIDS may represent an infection by a previously undescribed organism, a mutant of a known microorganism, or a multifactorial combination of environmental, immunologic, and genetic factors. As a consequence of the disease's seemingly irreversible ablation of the cell-mediated immune system, AIDS victims succumb to a variety of infections and/or unusual neoplasms. In its fully developed form, mortality approaches 100%. At autopsy the gross and microscopic pathology of the syndrome can be divided into three general categories: 1) morphologic manifestations of profound lymphoid depletion; 2) infections, usually with mixed opportunistic pathogens; and 3) unusual neoplasms, most frequently Kaposi's sarcoma or high-grade lymphomas. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 PMID:6311021

  17. Monocyte function in the acquired immune deficiency syndrome. Defective chemotaxis.

    PubMed Central

    Smith, P D; Ohura, K; Masur, H; Lane, H C; Fauci, A S; Wahl, S M

    1984-01-01

    The ineffective immune response in patients with the acquired immune deficiency syndrome (AIDS) contributes to severe and widespread infections and unrestricted growth by certain tumors. To determine whether monocyte dysfunction contributes to this immunosuppressed condition, we investigated monocyte chemotaxis in patients with AIDS. Using three different chemotactic stimuli, N-formylmethionylleucylphenylalanine, lymphocyte-derived chemotactic factor, and C5a des Arg, we studied the chemotactic responses of monocytes from seven homosexual men with AIDS, three homosexuals with lymphadenopathy and an abnormal immunological profile, seven healthy homosexual men, and 23 heterosexual control individuals. Monocytes from each of the AIDS patients with Kaposi's sarcoma and/or opportunistic infection exhibited a marked reduction in chemotaxis to all stimuli compared with the healthy control subjects. The reduced chemotactic responses were observed over a wide range of concentrations for each stimulus. Monocytes from AIDS patients who had clinically apparent opportunistic infection(s) exhibited a greater reduction in monocyte migration to all three stimuli than monocytes from the AIDS patient with only Kaposi's sarcoma. Monocytes from each of three homosexuals with lymphadenopathy and an abnormal immunological profile exhibited decreased chemotactic responses that were intermediate between those of the AIDS patients and the healthy heterosexual control subjects. In contrast to these findings, monocytes from each of seven healthy homosexuals exhibited normal chemotactic responses to the same stimuli. In addition, monocytes from AIDS patients exhibited reduced chemotaxis to soluble products of Giardia lamblia, one of several protozoan parasites prevalent in AIDS patients. Thus the immune abnormality in AIDS, previously thought to involve only the T-, B-, and natural killer lymphocytes, extends to the monocyte-macrophage. Defective monocyte migratory function may contribute to

  18. AIDS Federal Policy Act of 1987. Hearings on S. 1575: To Amend the Public Health Service Act To Establish a Grant Program To Provide for Counseling and Testing Services Relating to Acquired Immune Deficiency Syndrome and To Establish Certain Prohibitions for the Purpose of Protecting Individuals with Acquired Immune Deficiency Syndrome or Related Conditions. Committee on Labor and Human Resources. United States Senate, One Hundredth Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Committee on Labor and Human Resources.

    This document presents the text from two Senate hearings on the AIDS Federal Policy Act of 1987 which concerns voluntary testing for AIDS virus, education and counseling to stop the spread of AIDS (Acquired Immune Deficiency Syndrome), and confidentiality and discrimination against AIDS victims. In the first hearing, opening statements are…

  19. The Unspecific Side of Acquired Immunity Against Infectious Disease: Causes and Consequences

    PubMed Central

    Muraille, Eric

    2016-01-01

    Acquired immunity against infectious disease (AIID) has long been considered as strictly dependent on the B and T lymphocytes of the adaptive immune system. Consequently, AIID has been viewed as highly specific to the antigens expressed by pathogens. However, a growing body of data motivates revision of this central paradigm of immunology. Unrelated past infection, vaccination, and chronic infection have been found to induce cross-protection against numerous pathogens. These observations can be partially explained by the poly-specificity of antigenic T and B receptors, the Mackaness effect and trained immunity. In addition, numerous studies highlight the importance of microbiota composition on resistance to infectious disease via direct competition or modulation of the immune response. All of these data support the idea that a non-negligible part of AIID in nature can be nonspecific to the pathogens encountered and even of the antigens expressed by pathogens. As this protection may be dependent on the private T and B repertoires produced by the random rearrangement of genes, past immune history, chronic infection, and microbiota composition, it is largely unpredictable at the individual level. However, we can reasonably expect that a better understanding of the underlying mechanisms will allow us to statistically predict cross-protection at the population level. From an evolutionary perspective, selection of immune mechanisms allowing for partially nonspecific AIID would appear to be advantageous against highly polymorphic and rapidly evolving pathogens. This new emerging paradigm may have several important consequences on our understanding of individual infectious disease susceptibility and our conception of tolerance, vaccination and therapeutic strategies against infection and cancer. It also underscores the importance of viewing the microbiota and persisting infectious agents as integral parts of the immune system. PMID:26793171

  20. Cross-reactive acquired immunity influences transmission success of the Lyme disease pathogen, Borrelia afzelii.

    PubMed

    Jacquet, Maxime; Durand, Jonas; Rais, Olivier; Voordouw, Maarten J

    2015-12-01

    Cross-reactive acquired immunity in the vertebrate host induces indirect competition between strains of a given pathogen species and is critical for understanding the ecology of mixed infections. In vector-borne diseases, cross-reactive antibodies can reduce pathogen transmission at the vector-to-host and the host-to-vector lifecycle transition. The highly polymorphic, immunodominant, outer surface protein C (OspC) of the tick-borne spirochete bacterium Borrelia afzelii induces a strong antibody response in the vertebrate host. To test how cross-immunity in the vertebrate host influences tick-to-host and host-to-tick transmission, mice were immunized with one of two strain-specific recombinant OspC proteins (A3, A10), challenged via tick bite with one of the two B. afzelii ospC strains (A3, A10), and infested with xenodiagnostic ticks. Immunization with a given rOspC antigen protected mice against homologous strains carrying the same major ospC group allele but provided little or no cross-protection against heterologous strains carrying a different major ospC group allele. There were cross-immunity effects on the tick spirochete load but not on the probability of host-to-tick transmission. The spirochete load in ticks that had fed on mice with cross-immune experience was reduced by a factor of two compared to ticks that had fed on naive control mice. In addition, strain-specific differences in mouse spirochete load, host-to-tick transmission, tick spirochete load, and the OspC-specific IgG response revealed the mechanisms that determine variation in transmission success between strains of B. afzelii. This study shows that cross-immunity in infected vertebrate hosts can reduce pathogen load in the arthropod vector with potential consequences for vector-to-host pathogen transmission.

  1. Cross-reactive acquired immunity influences transmission success of the Lyme disease pathogen, Borrelia afzelii.

    PubMed

    Jacquet, Maxime; Durand, Jonas; Rais, Olivier; Voordouw, Maarten J

    2015-12-01

    Cross-reactive acquired immunity in the vertebrate host induces indirect competition between strains of a given pathogen species and is critical for understanding the ecology of mixed infections. In vector-borne diseases, cross-reactive antibodies can reduce pathogen transmission at the vector-to-host and the host-to-vector lifecycle transition. The highly polymorphic, immunodominant, outer surface protein C (OspC) of the tick-borne spirochete bacterium Borrelia afzelii induces a strong antibody response in the vertebrate host. To test how cross-immunity in the vertebrate host influences tick-to-host and host-to-tick transmission, mice were immunized with one of two strain-specific recombinant OspC proteins (A3, A10), challenged via tick bite with one of the two B. afzelii ospC strains (A3, A10), and infested with xenodiagnostic ticks. Immunization with a given rOspC antigen protected mice against homologous strains carrying the same major ospC group allele but provided little or no cross-protection against heterologous strains carrying a different major ospC group allele. There were cross-immunity effects on the tick spirochete load but not on the probability of host-to-tick transmission. The spirochete load in ticks that had fed on mice with cross-immune experience was reduced by a factor of two compared to ticks that had fed on naive control mice. In addition, strain-specific differences in mouse spirochete load, host-to-tick transmission, tick spirochete load, and the OspC-specific IgG response revealed the mechanisms that determine variation in transmission success between strains of B. afzelii. This study shows that cross-immunity in infected vertebrate hosts can reduce pathogen load in the arthropod vector with potential consequences for vector-to-host pathogen transmission. PMID:26384476

  2. Community Immunity: How Vaccines Protect Us All

    MedlinePlus

    ... disclaimer . Subscribe Community Immunity How Vaccines Protect Us All Parents know that kids are vulnerable to a ... countries and regions with lower vaccination rates. With all the international travel in the world these days, ...

  3. Trade-offs between acquired and innate immune defenses in humans

    PubMed Central

    McDade, Thomas W.; Georgiev, Alexander V.; Kuzawa, Christopher W.

    2016-01-01

    Immune defenses provide resistance against infectious disease that is critical to survival. But immune defenses are costly, and limited resources allocated to immunity are not available for other physiological or developmental processes. We propose a framework for explaining variation in patterns of investment in two important subsystems of anti-pathogen defense: innate (non-specific) and acquired (specific) immunity. The developmental costs of acquired immunity are high, but the costs of maintenance and activation are relatively low. Innate immunity imposes lower upfront developmental costs, but higher operating costs. Innate defenses are mobilized quickly and are effective against novel pathogens. Acquired responses are less effective against novel exposures, but more effective against secondary exposures due to immunological memory. Based on their distinct profiles of costs and effectiveness, we propose that the balance of investment in innate versus acquired immunity is variable, and that this balance is optimized in response to local ecological conditions early in development. Nutritional abundance, high pathogen exposure and low signals of extrinsic mortality risk during sensitive periods of immune development should all favor relatively higher levels of investment in acquired immunity. Undernutrition, low pathogen exposure, and high mortality risk should favor innate immune defenses. The hypothesis provides a framework for organizing prior empirical research on the impact of developmental environments on innate and acquired immunity, and suggests promising directions for future research in human ecological immunology. PMID:26739325

  4. Protective cellular retroviral immunity requires both CD4+ and CD8+ immune T cells.

    PubMed Central

    Hom, R C; Finberg, R W; Mullaney, S; Ruprecht, R M

    1991-01-01

    We have found previously that postexposure chemoprophylaxis with 3'-azido-3'-deoxythymidine (also known as zidovudine or AZT) in combination with recombinant human alpha A/D interferon fully protected mice exposed to a lethal dose of Rauscher murine leukemia virus (RLV) against viremia and disease. After cessation of therapy, over 90% of these mice were able to resist rechallenge with live RLV, thus demonstrating an acquired immunity. Adoptive cell transfer of 4 x 10(7) cells from immunized mice fully protected naive recipients from viremia and splenomegaly after RLV challenge. However, when these immune T cells were fractionated into CD4+ and CD8+ subpopulations, only partial protection was found when 4 x 10(7) T cells of either subset were given. Full protection against RLV challenge was seen again when the T-cell subsets from immunized mice were recombined and transferred at the same number into naive mice. We conclude that cellular immunity alone is protective and that both CD4+ and CD8+ cell types are required for conferring full protection against live virus challenge. Images PMID:1898666

  5. Immune control strategies for vaccinia virus-related laboratory-acquired infections.

    PubMed

    Wei, Qiang; Jiang, Meng Nan; Han, Jun; Wang, Zi Jun

    2014-02-01

    While presenting biological characteristics of vaccinia virus and laboratory-acquired infections during related research processes, this paper focuses on benefits and risks of vaccinia virus immunization in relation to laboratory-acquired infections, describes characteristics and the adaptation of vaccinia virus vaccine, analyses the role vaccinia virus immunization plays in the prevention and control of laboratory-acquired infections, and finally proposes solutions and countermeasures to further promote and implement immune control strategies. The problem related to immune strategy and laboratory- acquired infections which is being raised, analyzed and explored plays an active and instructive role in vaccinia virus related researches and laboratory- acquired infections, and also helps to recommend and develop relevant immune strategy for future vaccine control of such infections.

  6. Mycobacterium tuberculosis: Manipulator of Protective Immunity

    PubMed Central

    Korb, Vanessa C.; Chuturgoon, Anil A.; Moodley, Devapregasan

    2016-01-01

    Mycobacterium tuberculosis (MTB) is one of the most successful pathogens in human history and remains a global health challenge. MTB has evolved a plethora of strategies to evade the immune response sufficiently to survive within the macrophage in a bacterial-immunological equilibrium, yet causes sufficient immunopathology to facilitate its transmission. This review highlights MTB as the driver of disease pathogenesis and presents evidence of the mechanisms by which MTB manipulates the protective immune response into a pathological productive infection. PMID:26927066

  7. Erythema elevatum diutinum in acquired immune deficiency syndrome: Can it be an immune reconstitution inflammatory syndrome?

    PubMed Central

    Jose, Sheethal K; Marfatia, Yogesh S.

    2016-01-01

    A 47-year-old male with acquired immune deficiency syndrome (AIDS) presented with multiple hyperpigmented papules and nodules on both ankles, dorsum of bilateral feet and soles. It was associated with mild itching and pain. The patient was diagnosed with human immunodeficiency virus (HIV) in 2007. First-line antiretroviral therapy (ART) was started in 2009 to which he responded initially. He was shifted to second-line ART 11 months ago in March 2015 due to treatment failure as suggested by CD4 count of 50 cells/mm3. The present skin lesions started 2 months after the initiation of second-line ART. Differential diagnoses considered were Kaposi's sarcoma and immune reconstitution inflammatory syndrome (IRIS) related infections, but biopsy was suggestive of erythema elevatum diutinum (EED). Patient was started on oral dapsone 100 mg/day and increased to 200 mg/day to which he is responding gradually. In the present case, appearance of the lesions after initiation of second-line ART coupled with increase in CD4 count and decrease of viral load below undetectable level suggest that EED could be an IRIS. PMID:27190420

  8. Protective immune responses to fungal infections.

    PubMed

    Rivera, A

    2014-09-01

    The incidence of fungal infections has been on the rise over several decades. Fungal infections threaten animals, plants and humans alike and are thus of significant concern to scientists across disciplines. Over the last decade, significant advances on fungal immunology have lead to a better understanding of important mechanisms of host protection against fungi. In this article, I review recent advances of relevant mechanisms of immune-mediated protection to fungal infections.

  9. Norovirus Infection and Acquired Immunity in 8 Countries: Results From the MAL-ED Study

    PubMed Central

    Rouhani, Saba; Peñataro Yori, Pablo; Paredes Olortegui, Maribel; Siguas Salas, Mery; Rengifo Trigoso, Dixner; Mondal, Dinesh; Bodhidatta, Ladaporn; Platts-Mills, James; Samie, Amidou; Kabir, Furqan; Lima, Aldo; Babji, Sudhir; Mason, Carl J.; Kalam, Adil; Bessong, Pascal; Ahmed, Tahmeed; Mduma, Estomih; Bhutta, Zulfiqar A.; Lima, Ila; Ramdass, Rakhi; Lang, Dennis; George, Ajila; Zaidi, Anita K. M.; Kang, Gagandeep; Houpt, Eric; Kosek, Margaret N.

    2016-01-01

    Background. Norovirus is an important cause of childhood diarrhea. We present data from a longitudinal, multicountry study describing norovirus epidemiology during the first 2 years of life. Methods. A birth cohort of 1457 children across 8 countries contributed 7077 diarrheal stools for norovirus testing. A subset of 199 children contributed additional asymptomatic samples (2307) and diarrheal stools (770), which were used to derive incidence rates and evaluate evidence for acquired immunity. Results. Across sites, 89% of children experienced at least 1 norovirus infection before 24 months, and 22.7% of all diarrheal stools were norovirus positive. Severity of norovirus-positive diarrhea was comparable to other enteropathogens, with the exception of rotavirus. Incidence of genogroup II (GII) infection was higher than genogroup I and peaked at 6–11 months across sites. Undernutrition was a risk factor for symptomatic norovirus infection, with an increase in 1 standard deviation of length-for-age z score associated with a 17% reduction (odds ratio, 0.83 [95% confidence interval, .72–.97]; P = .011) in the odds of experiencing diarrhea when norovirus was present, after accounting for genogroup, rotavirus vaccine, and age. Evidence of acquired immunity was observed among GII infections only: Children with prior GII infection were found to have a 27% reduction in the hazard of subsequent infection (hazard ratio, 0.727; P = .010). Conclusions. The high prevalence of norovirus across 8 sites in highly variable epidemiologic settings and demonstration of protective immunity for GII infections provide support for investment in vaccine development. PMID:27013692

  10. Hypothesis: how licensed vaccines confer protective immunity.

    PubMed

    Robbins, J B; Schneerson, R; Szu, S C

    1996-01-01

    By examining experience with evaluation of licensed vaccines we theorize that a critical level of serum IgG confers protection against infectious diseases by killing or inactivating the inoculum. We found that efficacy is reliably predicted by measurement of serum antibodies elicited by vaccines, that serum IgG antibodies alone account for the protection conferred by passive immunization, that vaccine-induced "herd" immunity is best explained by inactivation of the inoculum on epithelial surfaces by serum antibodies and that serum antibodies induced by active immunization will neither treat disease symptoms nor eliminate the pathogen. If valid, this theory should facilitate research because knowledge of the pathogenesis of the disease symptoms may not be essential for vaccine development.

  11. Protective Immunity against Infection with Mycoplasma haemofelis

    PubMed Central

    Hicks, Chelsea A. E.; Willi, Barbara; Riond, Barbara; Novacco, Marilisa; Meli, Marina L.; Stokes, Christopher R.; Helps, Christopher R.; Hofmann-Lehmann, Regina

    2014-01-01

    Hemoplasmas are potentially zoonotic mycoplasmal pathogens, which are not consistently cleared by antibiotic therapy. Mycoplasma haemofelis is the most pathogenic feline hemoplasma species. The aim of this study was to determine how cats previously infected with M. haemofelis that had recovered reacted when rechallenged with M. haemofelis and to characterize the immune response following de novo M. haemofelis infection and rechallenge. Five specific-pathogen-free (SPF)-derived naive cats (group A) and five cats that had recovered from M. haemofelis infection (group B) were inoculated subcutaneously with M. haemofelis. Blood M. haemofelis loads were measured by quantitative PCR (qPCR), antibody response to heat shock protein 70 (DnaK) by enzyme-linked immunosorbent assay (ELISA), blood lymphocyte cell subtypes by flow cytometry, and cytokine mRNA levels by quantitative reverse transcriptase PCR. Group A cats all became infected with high bacterial loads and seroconverted, while group B cats were protected from reinfection, thus providing the unique opportunity to study the immunological parameters associated with this protective immune response against M. haemofelis. First, a strong humoral response to DnaK was only observed in group A, demonstrating that an antibody response to DnaK is not important for protective immunity. Second, proinflammatory cytokine interleukin-6 (IL-6) mRNA levels appeared to increase rapidly postinoculation in group B, indicating a possible role in protective immunity. Third, an increase in IL-12p35 and -p40 mRNA and decrease in the Th2/Th1 ratio observed in group A suggest that a Th1-type response is important in primary infection. This is the first study to demonstrate protective immunity against M. haemofelis reinfection, and it provides important information for potential future hemoplasma vaccine design. PMID:25410206

  12. Passive transfer of naturally acquired specific immunity against West Nile Virus to foals in a semi-feral pony herd.

    PubMed

    Wilkins, Pamela A; Glaser, Amy L; McDonnell, Sue M

    2006-01-01

    Horses naturally exposed to West Nile Virus (WNV) or vaccinated against WNV develop humoral immunity thought to be protective against development of clinical disease in exposed or infected animals. No reports evaluate the efficacy of passive transfer of naturally acquired specific WNV humoral immunity from dam to foal. The purpose of this study was to investigate passive transfer of naturally acquired immunity to WNV to foals born in a herd of semi-feral ponies, not vaccinated against WNV, in an endemic area, with many dams having seroconverted because of natural exposure. Microwell serum neutralization titers against WNV were determined in all mares and foals. Serum IgG concentration was determined in foals by serial radial immunodiffusion. Differences in IgG concentration between seropositive and seronegative foals were examined by means of the Mann-Whitney U-test. Linear regression was used to evaluate the association between mare and foal titers. Seventeen mare-foal pairs were studied; 1 foal had inadequate IgG concentration. IgG concentration was not different between seronegative and seropositive foals (P = .24). Mare and foal titers were significantly correlated in foals with adequate passive transfer of immunity (Spearman's rho = .84; P < .001); >90% of the foal's titer was explained by the mare's titer (R2 = 0.91; P < .001). Passive transfer of specific immunity to WNV is present in pony foals with adequate passive transfer of immunity born to seroconverted mares.

  13. The science base underlying research on acquired immune deficiency syndrome.

    PubMed

    Taube, S; Goldberg, M

    1983-01-01

    In order to define the clinical syndrome of AIDS and begin to deal with it effectively, scientists needed to understand how the immune system works. Fortunately, considerable knowledge was available: research in immunology over the last two decades had provided the technological advances and basic information about cell-mediated immunity that were necessary for identification of the syndrome. Without this knowledge base, immune suppression would not have been recognized as the common link among AIDS patients manifesting a variety of infections and unusual neoplasms. Similarly, research on infectious diseases, and in particular on the role of viruses as etiologic agents, has had an important bearing on understanding of AIDS. The epidemiologic data to date indicate that an infectious agent most likely is involved and that transmission of the disease requires intimate contact and perhaps some passage of blood. Among the candidates for viral agents are Epstein-Barr virus, cytomegalovirus, and human T-cell leukemia virus. All have been isolated from the cells of AIDS victims, but whether they are etiologic agents or opportunistic pathogens remains unresolved. Knowledge gained from the study of any of these viruses will contribute to understanding of AIDS, and vice versa. In this paper, we have attempted to show the integral relationship between specific research on AIDS and the ongoing research effort in related disciplines. It is important to recognize that effective research is the result of careful consideration of which questions can and should be addressed and the development of innovative approaches to gain answers to those questions. Research on AIDS is proceeding as rapidly as it is only because of the solid foundations that have been developed in the areas of immunology and virology. It is this base of research that ultimately will provide the rationale and the tools for solving new problems.

  14. Nasal Immunization with Lactococcus lactis Expressing the Pneumococcal Protective Protein A Induces Protective Immunity in Mice▿

    PubMed Central

    Medina, Marcela; Villena, Julio; Vintiñi, Elisa; Hebert, Elvira María; Raya, Raúl; Alvarez, Susana

    2008-01-01

    Nisin-controlled gene expression was used to develop a recombinant strain of Lactococcus lactis that is able to express the pneumococcal protective protein A (PppA) on its surface. Immunodetection assays confirmed that after the induction with nisin, the PppA antigen was predictably and efficiently displayed on the cell surface of the recombinant strain, which was termed L. lactis PppA. The production of mucosal and systemically specific antibodies in adult and young mice was evaluated after mice were nasally immunized with L. lactis PppA. Immunoglobulin M (IgM), IgG, and IgA anti-PppA antibodies were detected in the serum and bronchoalveolar lavage fluid of adult and young mice, which showed that PppA expressed in L. lactis was able to induce a strong mucosal and systemic immune response. Challenge survival experiments demonstrated that immunization with L. lactis PppA was able to increase resistance to systemic and respiratory infection with different pneumococcal serotypes, and passive immunization assays of naïve young mice demonstrated a direct correlation between anti-PppA antibodies and protection. The results presented in this study demonstrate three major characteristics of the effectiveness of nasal immunization with PppA expressed as a protein anchored to the cell wall of L. lactis: it elicited cross-protective immunity against different pneumococcal serotypes, it afforded protection against both systemic and respiratory challenges, and it induced protective immunity in mice of different ages. PMID:18390997

  15. Early developmental exposures shape trade-offs between acquired and innate immunity in humans

    PubMed Central

    Georgiev, Alexander V.; Kuzawa, Christopher W.; McDade, Thomas W.

    2016-01-01

    Background and objectives Life history theory predicts resource allocation trade-offs between competing functions and processes. We test the hypothesis that relative investment towards innate versus acquired immunity in humans is subject to such trade-offs and that three types of early developmental exposures are particularly salient in shaping adult immunophenotype: (i) pathogen exposure, (ii) nutritional resources; and (iii) extrinsic mortality cues. Methodology We quantified one aspect each of innate and acquired immune function, via C-reactive protein and Epstein–Barr virus antibodies, respectively, in a sample of 1248 men and women from the Philippines (ca. 21.5 years old). Early developmental exposures were assessed via long-term data collected prospectively since participants’ birth (1983–4). We calculated a standardized ratio to assess relative bias towards acquired versus innate immune function and examined its relationship to a suite of predictors via multiple regression. Results In partial support of our predictions, some of the measures of higher pathogen exposure, greater availability of nutritional resources, and lower extrinsic mortality cues in early life were associated with a bias toward acquired immunity in both men and women. The immune profile of women, in particular, appeared to be more sensitive to early life pathogen exposures than those of men. Finally, contrary to prediction, women exhibited a greater relative investment toward innate, not acquired, immunity. Conclusions and implications Early environments can exert considerable influence on the development of immunity. They affect trade-offs between innate and acquired immunity, which show adaptive plasticity and may differ in their influence in men and women. PMID:27530543

  16. Radiation-resistant acquired immunity of vaccinated mice to Schistosoma mansoni

    SciTech Connect

    Aitken, R.; Coulson, P.S.; Dixon, B.; Wilson, R.A.

    1987-11-01

    Vaccination of mice with attenuated cercariae of Schistosoma mansoni induces specific acquired resistance to challenge infection. This resistance is immunologically-mediated, possibly via a delayed-type hypersensitivity. Studies of parasite migration have shown that the protective mechanism operates most effectively in the lungs of vaccinated mice. We have probed the mechanism by exposing mice to 500 rads of gamma radiation before challenge infection. Our results show that the effector mechanism operative against challenge larvae is resistant to radiation. In contrast, classical immune responses are markedly suppressed by the same treatment. While leukocyte populations in the blood fall dramatically after irradiation, numbers of cells recoverable by bronchoalveolar lavage are unaffected. We suggest that vaccination with attenuated cercariae establishes populations of sensitized cells in the lungs which trigger the mechanism of resistance when challenge schistosomula migrate through pulmonary capillary beds. Although the cells may be partially disabled by irradiation, they remain responsive to worm antigens and thereby capable of initiating the elimination mechanism. This hypothesis would explain the radiation resistance of vaccine-induced immunity to S. mansoni.

  17. Protective immune mechanisms in helminth infection

    PubMed Central

    Anthony, Robert M.; Rutitzky, Laura I.; Urban, Joseph F.; Stadecker, Miguel J.; Gause, William C.

    2008-01-01

    Important insights have recently been gained in our understanding of how host immune responses mediate resistance to parasitic helminths and control associated pathological responses. Although similar cells and cytokines are evoked in response to infection by helminths as diverse as nematodes and schistosomes, the components of the response that mediate protection are dependent on the particular parasite. In this Review, we examine recent findings regarding the mechanisms of protection in helminth infections that have been elucidated in murine models and discuss the implications of these findings in terms of future therapies. PMID:18007680

  18. Toward immunogenetic studies of amphibian chytridiomycosis: Linking innate and acquired immunity

    USGS Publications Warehouse

    Richmond, J.Q.; Savage, Anna E.; Zamudio, Kelly R.; Rosenblum, E.B.

    2009-01-01

    Recent declines in amphibian diversity and abundance have contributed significantly to the global loss of biodiversity. The fungal disease chytridiomycosis is widely considered to be a primary cause of these declines, yet the critical question of why amphibian species differ in susceptibility remains unanswered. Considerable evidence links environmental conditions and interspecific variability of the innate immune system to differential infection responses, but other sources of individual, population, or species-typical variation may also be important. In this article we review the preliminary evidence supporting a role for acquired immune defenses against chytridiomycosis, and advocate for targeted investigation of genes controlling acquired responses, as well as those that functionally bridge the innate and acquired immune systems. Immunogenetic data promise to answer key questions about chytridiomycosis susceptibility and host-pathogen coevolution, and will draw much needed attention to the importance of considering evolutionary processes in amphibian conservation management and practice. ?? 2009 by American Institute of Biological Sciences.

  19. An ongoing tragedy: the acquired immune deficiency syndrome (AIDS).

    PubMed

    Desai, B T

    1989-01-01

    The AIDS epidemic has, to date, had only a minimal impact in India; however, given the low health status of the population and the lack of adequate health care facilities, the emergence of AIDS on a wider scale would be devastating. India's human immunodeficiency virus (HIV) seropositivity rate now stands at about 2-3/1000 people tested. In what is suspected to be a racially motivated move, the Government of India has embarked on testing all foreign students (most of whom are from Africa) for HIV and is returning all those who test seropositive to their countries of origin. Of concern is the steady increase in HIV infection in professional blood donors (1.5/1000 in late 1988). Mandatory screening of donated blood is prohibitively expensive in India, and none of the 9 companies that manufacture blood products in India test their donors for HIV infection. Another concern is the finding that 1 of every 6 prostitutes in Bombay is infected with HIV. The response of the Indian Government to the AIDS threat has tended to be punitive toward AIDS victims rather than based on a sound preventive strategy. For example, the 1989 AIDS Prevention Bill forces individuals who are infected with HIV to reveal their past sexual partners, empowers authorities to hospitalize AIDS victims and drug addicts, and contains no provisions to protect the human and civil rights of AIDS victims. The mass media have treated AIDS in a sensationalized manner rather than presenting scientific information about the prevention and transmission of the disease. It is essential that the Government of India--and all world governments--realize that punitive measures will do little to reduce the spread of AIDS. Needed, instead, is a global prevention and control effort based on generosity and compassion.

  20. Acquired immunity and asymptomatic reservoir impact on frontline and airport ebola outbreak syndromic surveillance and response.

    PubMed

    Tambo, Ernest; Xiao-Nong, Zhou

    2014-01-01

    The number of surveillance networks for infectious disease diagnosis and response has been growing. In 2000, the World Health Organization (WHO) established the Global Outbreak Alert and Response Network, which has been endorsed by each of the 46 WHO African members since then. Yet, taming the dynamics and plague of the vicious Ebola virus disease (EVD) in African countries has been patchy and erratic due to inadequate surveillance and contact tracing, community defiance and resistance, a lack of detection and response systems, meager/weak knowledge and information on the disease, inadequacies in protective materials protocols, contact tracing nightmare and differing priorities at various levels of the public health system. Despite the widespread acceptance of syndromic surveillance (SS) systems, their ability to provide early warning alerts and notifications of outbreaks is still unverified. Information is often too limited for any outbreak, or emerging or otherwise unexpected disease, to be recognized at either the community or the national level. Indeed, little is known about the role and the interactions between the Ebola infection and exposure to other syndemics and the development of acquired immunity, asymptomatic reservoir, and Ebola seroconversion. Can lessons be learnt from smallpox, polio, and influenza immunity, and can immunization against these serve as a guide? In most endemic countries, community health centers and disease control and prevention at airports solely relies on passive routine immunization control and reactive syndromic response. The frontline and airport Ebola SS systems in West Africa have shown deficiencies in terms of responding with an alarming number of case fatalities, and suggest that more detailed insights into Ebola, and proactive actions, are needed. The quest for effective early indicators (EEE) in shifting the public and global health paradigm requires the development and implementation of a comprehensive and effective

  1. Acquired Immune Deficiency Syndrome, AIDS: A Selected Bibliography of Federal Government Publications. Research Guide 90 104.

    ERIC Educational Resources Information Center

    Alexander, Margaret

    This research guide presents a selected bibliography of federal government publications about the Acquired Immune Deficiency Syndrome (AIDS). These documents are listed in five categories: (1) Bibliographies (7); (2) Congressional Publications (69 hearings and reports); (3) Executive Branch Publications (43 reports); (4) Federal Government…

  2. Semantic Differential Responses to Educational Posters on Acquired Immune Deficiency Syndrome (AIDS).

    ERIC Educational Resources Information Center

    Wilson, Christopher; Stewin, Leonard L.

    1992-01-01

    Undergraduate students (n=131) responded to eight educational posters dealing with the Acquired Immune Deficiency Syndrome (AIDS) using a nine-item semantic differential scale. Two posters were consistently rated as more informative, reassuring, effective, decent, and better than the others. The first utilized an objective and informative…

  3. Teaching AIDS. A Resource Guide on Acquired Immune Deficiency Syndrome. Third Edition.

    ERIC Educational Resources Information Center

    Quackenbush, Marcia; Sargent, Pamela

    The first edition of this resource guide for educators on how to teach students about Acquired Immune Deficiency Syndrome (AIDS) was published in 1986. Since then, basic facts about the transmission and prevention of the AIDS virus have not changed substantially. The terminologies about the disease, however, have changed and the changing…

  4. Schistosomiasis Coinfection in Children Influences Acquired Immune Response against Plasmodium falciparum Malaria Antigens

    PubMed Central

    Gaayeb, Lobna; Schacht, Anne-Marie; Charrier, Nicole; De Clerck, Dick; Dompnier, Jean-Pierre; Pillet, Sophie; Garraud, Olivier; N'Diaye, Abdoulaye A.; Riveau, Gilles

    2010-01-01

    Background Malaria and schistosomiasis coinfection frequently occurs in tropical countries. This study evaluates the influence of Schistosoma haematobium infection on specific antibody responses and cytokine production to recombinant merozoite surface protein-1-19 (MSP1-19) and schizont extract of Plasmodium falciparum in malaria-infected children. Methodology Specific IgG1 to MSP1-19, as well as IgG1 and IgG3 to schizont extract were significantly increased in coinfected children compared to P. falciparum mono-infected children. Stimulation with MSP1-19 lead to a specific production of both interleukin-10 (IL-10) and interferon-γ (IFN-γ), whereas the stimulation with schizont extract produced an IL-10 response only in the coinfected group. Conclusions Our study suggests that schistosomiasis coinfection favours anti-malarial protective antibody responses, which could be associated with the regulation of IL-10 and IFN-γ production and seems to be antigen-dependent. This study demonstrates the importance of infectious status of the population in the evaluation of acquired immunity against malaria and highlights the consequences of a multiple infection environment during clinical trials of anti-malaria vaccine candidates. PMID:20856680

  5. A cascade reaction network mimicking the basic functional steps of acquired immune response

    PubMed Central

    Han, Da; Wu, Cuichen; You, Mingxu; Zhang, Tao; Wan, Shuo; Chen, Tao; Qiu, Liping; Zheng, Zheng; Liang, Hao; Tan, Weihong

    2015-01-01

    Biological systems use complex ‘information processing cores’ composed of molecular networks to coordinate their external environment and internal states. An example of this is the acquired, or adaptive, immune system (AIS), which is composed of both humoral and cell-mediated components. Here we report the step-by-step construction of a prototype mimic of the AIS which we call Adaptive Immune Response Simulator (AIRS). DNA and enzymes are used as simple artificial analogues of the components of the AIS to create a system which responds to specific molecular stimuli in vitro. We show that this network of reactions can function in a manner which is superficially similar to the most basic responses of the vertebrate acquired immune system, including reaction sequences that mimic both humoral and cellular responses. As such, AIRS provides guidelines for the design and engineering of artificial reaction networks and molecular devices. PMID:26391084

  6. Small intestinal lymphoma in three patients with acquired immune deficiency syndrome.

    PubMed

    Steinberg, J J; Bridges, N; Feiner, H D; Valensi, Q

    1985-01-01

    Three cases of small bowel lymphoma in young homosexual men are presented. All three had acquired immune deficiency syndrome as demonstrated by demography, sexual history, cachexia, opportunistic infections by Cytomegalovirus, Pneumocystis carinii, atypical Mycobacterium, Candida, and/or evidence of immune deficiency, such as skin test anergy, lymphopenia, inversion of T-helper/T-suppressor ratio, and diminished lymphocyte response to either phytohemmaglutinin or pokeweed mitogen. All had peripheral and/or abdominal lymphadenopathy, and gastrointestinal symptoms, e.g., diarrhea, spasms, constipation, and oral candidiasis. The diagnosis of lymphoma was made at laparotomy in all cases. All three had complete removal of localized tumor (stage Ie or IIe), yet died within 6 months of surgery and/or chemotherapy. Thus gastrointestinal complaints may not always be related to "gay bowel" syndrome, or other infectious diseases in patients with acquired immune deficiency syndrome. Small intestinal lymphoma should be added to the list of neoplasms to which this group is susceptible.

  7. Effects of antibiotics on acquired immunity in vivo--current state of knowledge.

    PubMed

    Pomorska-Mól, M; Pejsak, Z

    2012-01-01

    Antibiotics are widely used in the therapy of infections. Besides the respective interactions between antibiotics and pathogens it seems that antibiotics also directly interact with the immune system. Some commonly used antibiotics are currently known to have effects on the innate immune response, as shown by in vitro, ex vivo and also in vivo animal experiments and clinical studies. Most of the experimental papers published to date, as well as most reviews, relate to how antibiotics affect the innate immune response or non-specific monocyte or lymphocyte proliferation. However the effects of antibiotics on the adaptive immune response are still not well characterized. This review of the literature considering different in vivo experiments indicate the real importance of interrelations existing between acquired immune responses and antibiotics, however, the mechanism of immunomodulatory effects of antibiotics are still poorly understood. Currently, data on the immunomodulating effects of antibiotics often remain heterogeneous, contradictory or insufficient, but most results published to date revealed the immunosuppressive effect of antibiotics on the antigen-specific immune response in vivo. In pigs as well as in poultry herds, it is not uncommon practice to add antibiotics to drinking water or feed at the time of vaccination. Information on the effects of such practices on the immune system of animals is restricted and more in vivo studies are needed to investigate the effects of antimicrobial drugs on the immune system, especially in the field conditions.

  8. Non-genomic and Immune Evolution of Melanoma Acquiring MAPKi Resistance.

    PubMed

    Hugo, Willy; Shi, Hubing; Sun, Lu; Piva, Marco; Song, Chunying; Kong, Xiangju; Moriceau, Gatien; Hong, Aayoung; Dahlman, Kimberly B; Johnson, Douglas B; Sosman, Jeffrey A; Ribas, Antoni; Lo, Roger S

    2015-09-10

    Clinically acquired resistance to MAPK inhibitor (MAPKi) therapies for melanoma cannot be fully explained by genomic mechanisms and may be accompanied by co-evolution of intra-tumoral immunity. We sought to discover non-genomic mechanisms of acquired resistance and dynamic immune compositions by a comparative, transcriptomic-methylomic analysis of patient-matched melanoma tumors biopsied before therapy and during disease progression. Transcriptomic alterations across resistant tumors were highly recurrent, in contrast to mutations, and were frequently correlated with differential methylation of tumor cell-intrinsic CpG sites. We identified in the tumor cell compartment supra-physiologic c-MET up-expression, infra-physiologic LEF1 down-expression and YAP1 signature enrichment as drivers of acquired resistance. Importantly, high intra-tumoral cytolytic T cell inflammation prior to MAPKi therapy preceded CD8 T cell deficiency/exhaustion and loss of antigen presentation in half of disease-progressive melanomas, suggesting cross-resistance to salvage anti-PD-1/PD-L1 immunotherapy. Thus, melanoma acquires MAPKi resistance with highly dynamic and recurrent non-genomic alterations and co-evolving intra-tumoral immunity.

  9. Non-genomic and Immune Evolution of Melanoma Acquiring MAPKi Resistance

    PubMed Central

    Hugo, Willy; Shi, Hubing; Sun, Lu; Piva, Marco; Song, ChunYing; Kong, Xiangju; Moriceau, Gatien; Hong, Aayoung; Dahlman, Kimberly B.; Johnson, Douglas B.; Sosman, Jeffrey A.; Ribas, Antoni; Lo, Roger S.

    2015-01-01

    SUMMARY Clinically acquired resistance to MAPK inhibitor (MAPKi) therapies for melanoma cannot be fully explained by genomic mechanisms and may be accompanied by co-evolution of intra-tumoral immunity. We sought to discover non-genomic mechanisms of acquired resistance and dynamic immune compositions by a comparative, transcriptomic-methylomic analysis of patient-matched melanoma tumors biopsied before therapy and during disease progression. Transcriptomic alterations across resistant tumors were highly recurrent, in contrast to mutations, and were frequently correlated with differential methylation of tumor cell-intrinsic CpG sites. We identified in the tumor cell compartment supra-physiologic c-MET up-expression, infra-physiologic LEF1 down-expression, and YAP1 signature enrichment as drivers of acquired resistance. Importantly, high intra-tumoral cytolytic T-cell inflammation prior to MAPKi therapy preceded CD8 T-cell deficiency/exhaustion and loss of antigen-presentation in half of disease-progressive melanomas, suggesting cross-resistance to salvage anti-PD-1/PD-L1 immunotherapy. Thus, melanoma acquires MAPKi-resistance with highly dynamic and recurrent non-genomic alterations and co-evolving intra-tumoral immunity. PMID:26359985

  10. Smallpox vaccines: targets of protective immunity.

    PubMed

    Moss, Bernard

    2011-01-01

    The eradication of smallpox, one of the great triumphs of medicine, was accomplished through the prophylactic administration of live vaccinia virus, a comparatively benign relative of variola virus, the causative agent of smallpox. Nevertheless, recent fears that variola virus may be used as a biological weapon together with the present susceptibility of unimmunized populations have spurred the development of new-generation vaccines that are safer than the original and can be produced by modern methods. Predicting the efficacy of such vaccines in the absence of human smallpox, however, depends on understanding the correlates of protection. This review outlines the biology of poxviruses with particular relevance to vaccine development, describes protein targets of humoral and cellular immunity, compares animal models of orthopoxvirus disease with human smallpox, and considers the status of second- and third-generation smallpox vaccines.

  11. Primary cardiac lymphoma in a patient with acquired immune deficiency syndrome

    SciTech Connect

    Constantino, A.; West, T.E.; Gupta, M.; Loghmanee, F.

    1987-12-01

    A 34-year-old male prisoner with a history of intravenous drug abuse presented with fever, lymphadenopathy, weight loss, and recent onset of congestive heart failure. Serologic testing was positive for antibodies to human immune deficiency virus. There was intense myocardial uptake of gallium. Autopsy showed a primary immunoblastic lymphoma involving only the myocardium. While primary cardiac lymphoma is an extremely rare condition, the incidence may be higher in patients with acquired immune deficiency syndrome (AIDS) and should be suspected in cases with atypical cardiomyopathy.

  12. Heterotopic ossification (myositis ossificans) in acquired immune deficiency syndrome. Detection by gallium scintigraphy.

    PubMed

    Drane, W E; Tipler, B M

    1987-06-01

    A case of heterotopic ossification (myositis ossificans) secondary to the central nervous system complications of acquired immune deficiency syndrome (AIDS) is reported. Because of the overwhelming suspicion of infection in this patient, this diagnosis was not considered until a gallium scan revealed the typical findings of heterotopic ossification. Because of the increasing utilization of gallium imaging in the AIDS population, every imaging specialist should be aware of this potential disorder.

  13. Physicians' obligations to patients infected with Ebola: echoes of acquired immune deficiency syndrome.

    PubMed

    Minkoff, Howard; Ecker, Jeffrey

    2015-04-01

    Physicians across the United States are engaged in training in the identification, isolation, and initial care of patients with Ebola. Some will be asked to do more. The issue this viewpoint will address is the moral obligation of physicians to participate in these activities. In order to do so the implicit contract between society and its physicians will be considered, as will many of the arguments that are redolent of those that were litigated 30 years ago when acquired immune deficiency syndrome (AIDS) was raising public fears to similar levels, and some physicians were publically proclaiming their unwillingness to render care to those individuals. We will build the case that if steps are taken to reduce risks-optimal personal protective equipment and training-to what is essentially the lowest possible level then rendering care should be seen as obligatory. If not, as in the AIDS era there will be an unfair distribution of risk, with those who take their obligations seriously having to go beyond their fair measure of exposure. It would also potentially undermine patients' faith in the altruism of physicians and thereby degrade the esteem in which our profession is held and the trust that underpins the therapeutic relationship. Finally there is an implicit contract with society. Society gives tremendously to us; we encumber a debt from all society does and offers, a debt for which recompense is rarely sought. The mosaic of moral, historical, and professional imperatives to render care to the infected all echoes the words of medicine's moral leaders in the AIDS epidemic. Arnold Relman perhaps put it most succinctly, "the risk of contracting the patient's disease is one of the risks that is inherent in the profession of medicine. Physicians who are not willing to accept that risk…ought not be in the practice of medicine." PMID:25530596

  14. Potential Suppressive Effects of Two C60 Fullerene Derivatives on Acquired Immunity

    NASA Astrophysics Data System (ADS)

    Hirai, Toshiro; Yoshioka, Yasuo; Udaka, Asako; Uemura, Eiichiro; Ohe, Tomoyuki; Aoshima, Hisae; Gao, Jian-Qing; Kokubo, Ken; Oshima, Takumi; Nagano, Kazuya; Higashisaka, Kazuma; Mashino, Tadahiko; Tsutsumi, Yasuo

    2016-10-01

    The therapeutic effects of fullerene derivatives on many models of inflammatory disease have been demonstrated. The anti-inflammatory mechanisms of these nanoparticles remain to be elucidated, though their beneficial roles in allergy and autoimmune diseases suggest their suppressive potential in acquired immunity. Here, we evaluated the effects of C60 pyrrolidine tris-acid (C60-P) and polyhydroxylated fullerene (C60(OH)36) on the acquired immune response in vitro and in vivo. In vitro, both C60 derivatives had dose-dependent suppressive effects on T cell receptor-mediated activation of T cells and antibody production by B cells under anti-CD40/IL-4 stimulation, similar to the actions of the antioxidant N-acetylcysteine. In addition, C60-P suppressed ovalbumin-specific antibody production and ovalbumin-specific T cell responses in vivo, although T cell-independent antibodies responses were not affected by C60-P. Together, our data suggest that fullerene derivatives can suppress acquired immune responses that require T cells.

  15. Nasal immunization with major epitope-containing ApxIIA toxin fragment induces protective immunity against challenge infection with Actinobacillus pleuropneumoniae in a murine model.

    PubMed

    Seo, Ki-Weon; Kim, Sae-Hae; Park, Jisang; Son, Youngok; Yoo, Han Sang; Lee, Kyung-Yeol; Jang, Yong-Suk

    2013-01-15

    Actinobacillus pleuropneumoniae is an infective agent that leads to porcine pleuropneumonia, a disease that causes severe economic losses in the swine industry. Based on the fact that the respiratory tract is the primary site for bacterial infection, it has been suggested that bacterial exclusion in the respiratory tract through mucosal immune induction is the most effective disease prevention strategy. ApxIIA is a vaccine candidate against A. pleuropneumoniae infection, and fragment #5 (aa. 439-801) of ApxIIA contains the major epitopes for effective vaccination. In this study, we used mice to verify the efficacy of intranasal immunization with fragment #5 in the induction of protective immunity against nasal challenge with A. pleuropneumoniae and compared its efficacy with that of subcutaneous immunization. Intranasal immunization of the fragment induced significantly higher systemic and mucosal immune responses measured at the levels of antigen-specific antibodies, cytokine-secreting cells after antigen exposure, and antigen-specific lymphocyte proliferation. Intranasal immunization not only efficiently inhibited the bacterial colonization in respiratory organs, but also prevented alveolar tissue damage in infectious condition similar to that of a contaminated pig. Moreover, intranasal immunization with fragment #5 provided acquired protective immunity against intranasal challenge with A. pleuropneumoniae serotype 2. In addition, it conferred cross-protection against serotype 5, a heterologous pathogen that causes severe disease by ApxI and ApxII secretion. Collectively, intranasal immunization with fragment #5 of ApxIIA can be considered an efficient protective immunization procedure against A. pleuropneumoniae infection.

  16. Protective host immune responses to Salmonella infection.

    PubMed

    Pham, Oanh H; McSorley, Stephen J

    2015-01-01

    Salmonella enterica serovars Typhi and Paratyphi are the causative agents of human typhoid fever. Current typhoid vaccines are ineffective and are not widely used in endemic areas. Greater understanding of host-pathogen interactions during Salmonella infection should facilitate the development of improved vaccines to combat typhoid and nontyphoidal Salmonellosis. This review will focus on our current understanding of Salmonella pathogenesis and the major host immune components that participate in immunity to Salmonella infection. In addition, recent findings regarding host immune mechanisms in response to Salmonella infection will be also discussed, providing a new perspective on the utility of improved tools to study the immune response to Salmonella infections.

  17. Molecular characteristics of Illicium verum extractives to activate acquired immune response

    PubMed Central

    Peng, Wanxi; Lin, Zhi; Wang, Lansheng; Chang, Junbo; Gu, Fangliang; Zhu, Xiangwei

    2015-01-01

    Illicium verum, whose extractives can activate the demic acquired immune response, is an expensive medicinal plant. However, the rich extractives in I. verum biomass were seriously wasted for the inefficient extraction and separation processes. In order to further utilize the biomedical resources for the good acquired immune response, the four extractives were obtained by SJYB extraction, and then the immunology moleculars of SJYB extractives were identified and analyzed by GC–MS. The result showed that the first-stage extractives contained 108 components including anethole (40.27%), 4-methoxy-benzaldehyde (4.25%), etc.; the second-stage extractives had 5 components including anethole (84.82%), 2-hydroxy-2-(4-methoxy-phenyl)-n-methyl-acetamide (7.11%), etc.; the third-stage extractives contained one component namely anethole (100%); and the fourth-stage extractives contained 5 components including cyclohexyl-benzene (64.64%), 1-(1-methylethenyl)-3-(1-methylethyl)-benzene (17.17%), etc. The SJYB extractives of I. verum biomass had a main retention time between 10 and 20 min what’s more, the SJYB extractives contained many biomedical moleculars, such as anethole, eucalyptol, [1S-(1α,4aα,10aβ)]-1,2,3,4,4a,9,10,10a-octahydro-1,4a-dimethyl-7-(1-methylethyl)-1-phenanthrenecarboxylic acid, stigmast-4-en-3-one, γ-sitosterol, and so on. So the functional analytical results suggested that the SJYB extractives of I. verum had a function in activating the acquired immune response and a huge potential in biomedicine. PMID:27081359

  18. Length of survival of patients with acquired immune deficiency syndrome in the United Kingdom.

    PubMed Central

    Marasca, G; McEvoy, M

    1986-01-01

    An analysis of the lengths of survival of patients with the acquired immune deficiency syndrome presenting with different opportunistic diseases was performed using epidemiological data routinely collected at the PHLS Communicable Disease Surveillance Centre. The overall crude case fatality rate was 55.4% (93/168). The median survival times were: 21.2 months for Kaposi's sarcoma, 12.5 months for Pneumocystis carinii pneumonia, and 13.3 months for other opportunistic infections. The shortest median survival time (6.6 months) was found for those with both Kaposi's sarcoma and P carinii pneumonia. There were significant differences between durations of survival of patients with Kaposi's sarcoma and those with all other diseases, which indicated impaired cellular immunity apart from opportunistic infections. This analysis shows that those with Kaposi's sarcoma alone have the most favourable prognosis. PMID:3089373

  19. Differences in acquired immune deficiency syndrome treatment and evaluation strategies between Chinese and Western Medicine.

    PubMed

    Liu, Zhibin; Li, Xia; Yang, Jiping; Xu, Liran; Guo, Huijun

    2015-12-01

    Complementary and alternative medicine, including Chinese medicine (CM), has been used to treat acquired immune deficiency syndrome (AIDS) foralmost 30 years. We aimed to compare the main differences between AIDS treatment and evaluation strategies between CM and Western Medicine (WM), and analyze advantages and disadvantages. The characteristics of integrative medicine (IM), based on CM and WM, include a patient-centered mode of medicine based on evidence. IM focuses on complex intervention and management with systemic and individual treatment. The evaluation indexes of IM might consist of objective indicators and subjective indexes. IM might be a more valuable method for treating AIDS in the future instead of WM or CM alone.

  20. [Changes in the thoracic roentgen image in patients with acquired immune deficiency syndrome].

    PubMed

    Pölzleitner, D; Herold, C; Tscholakoff, D; Imhof, H

    1990-01-19

    Since the earliest reports of what was later termed the acquired immune deficiency syndrome (AIDS) appeared in 1980/81, with the recognition of opportunistic infections and Kaposi's sarcoma in homosexual men and i.v. drug abusers, more than 60% of AIDS patients develop pulmonary manifestations at some time in the course of their disease. Radiographic evaluation of the chest plays an important role in diagnosis. In fact, radiological changes are unspecific and either bacteriological proof or histological verification needs to be confirmed.

  1. Acquired immune response to oncogenic human papillomavirus associated with prophylactic cervical cancer vaccines.

    PubMed

    Einstein, Mark H

    2008-04-01

    Human papillomavirus (HPV) is a common infection among women and a necessary cause of cervical cancer. Oncogenic HPV types infecting the anogenital tract have the potential to induce natural immunity, but at present we do not clearly understand the natural history of infection in humans and the mechanisms by which the virus can evade the host immune response. Natural acquired immune responses against HPV may be involved in the clearance of infection, but persistent infection with oncogenic virus types leads to the development of precancerous lesions and cancer. B cell responses are important for viral neutralization, but antibody responses in patients with cervical cancer are poor. Prophylactic vaccines targeting oncogenic virus types associated with cervical cancer have the potential to prevent up to 80% of cervical cancers by targeting HPV types 16 and 18. Clinical data show that prophylactic vaccines are effective in inducing antibody responses and in preventing persistent infection with HPV, as well as the subsequent development of high-grade cervical intraepithelial neoplasia. This article reviews the known data regarding natural immune responses to HPV and those developed by prophylactic vaccination.

  2. Optimal vaccination and bednet maintenance for the control of malaria in a region with naturally acquired immunity.

    PubMed

    Prosper, Olivia; Ruktanonchai, Nick; Martcheva, Maia

    2014-07-21

    Following over two decades of research, the malaria vaccine candidate RTS,S has reached the final stages of vaccine trials, demonstrating an efficacy of roughly 50% in young children. Regions with high malaria prevalence tend to have high levels of naturally acquired immunity (NAI) to severe malaria; NAI is caused by repeated exposure to infectious bites and results in large asymptomatic populations. To address concerns about how these vaccines will perform in regions with existing NAI, we developed a simple malaria model incorporating vaccination and NAI. Typically, if the basic reproduction number (R0) for malaria is greater than unity, the disease will persist; otherwise, the disease will become extinct. However, analysis of this model revealed that NAI, compounded by a subpopulation with only partial protection to malaria, may render vaccination efforts ineffective and potentially detrimental to malaria control, by increasing R0 and increasing the likelihood of malaria persistence even when R0<1. The likelihood of this scenario increases when non-immune infected individuals are treated disproportionately compared with partially immune individuals - a plausible scenario since partially immune individuals are more likely to be asymptomatically infected. Consequently, we argue that active case-detection of asymptomatic infections is a critical component of an effective malaria control program. We then investigated optimal vaccination and bednet control programs under two endemic settings with varying levels of naturally acquired immunity: a typical setting under which prevalence decays when R0<1, and a setting in which subthreshold endemic equilibria exist. A qualitative comparison of the optimal control results under the first setting revealed that the optimal policy differs depending on whether the goal is to reduce total morbidity, or to reduce clinical infections. Furthermore, this comparison dictates that control programs should place less effort in

  3. Antimicrobial synergism against Mycobacterium avium complex strains isolated from patients with acquired immune deficiency syndrome.

    PubMed Central

    Yajko, D M; Kirihara, J; Sanders, C; Nassos, P; Hadley, W K

    1988-01-01

    Pairs of 11 antimicrobial agents were tested in vitro for their ability to act synergistically against three strains of Mycobacterium avium complex isolated from patients with acquired immune deficiency syndrome. From the combinations tested, four drugs (ethambutol, rifampin, ciprofloxacin, and erythromycin) were selected for more extensive study against 20 strains of M. avium complex. The inhibitory and killing synergism obtained with combinations of two, three, or four drugs was assessed by determining the fractional inhibitory concentration index and fractional bactericidal concentration index. Inhibitory synergism occurred against 90 to 100% of the strains for all drug combinations in which ethambutol was included. Killing synergism occurred against 85 to 95% of the strains when ethambutol was used in combinations which included either rifampin or ciprofloxacin. However, killing synergism occurred against only 45% of the strains when drugs were tested at concentrations that can be obtained in patient serum. In other experiments, rifabutin (Ansamycin) gave results that were comparable to those obtained with rifampin. Clofazimine did not show synergistic killing activity at a concentration that is achievable in serum for any of the drugs tested. Our results indicate that there is considerable variability in the antimicrobial susceptibility of M. avium isolates obtained from patients with acquired immune deficiency syndrome. This variability could have significant impact on the clinical response to various therapies. PMID:3196000

  4. Indirect effects by meningococcal vaccines: herd protection versus herd immunity.

    PubMed

    Bröker, Michael

    2011-08-01

    The term "herd immunity" for the indirect effect of meningococcal conjugate vaccines is inaccurate. A more appropriate term is "herd protection," because this term correctly describes the public effects imparted by vaccination campaigns against the meningococcus.

  5. Governmental Immunity for Public Education: A Shield of Legal Protection.

    ERIC Educational Resources Information Center

    Aitken, Joan E.

    The American tradition of sovereign immunity and the Eleventh Amendment of the United States Constitution have provided certain legal protection to government personnel, including leaders of public elementary, secondary, and post-secondary institutions, but the concept of governmental immunity may be difficult to understand as it applies to…

  6. Strong density-dependent competition and acquired immunity constrain parasite establishment: implications for parasite aggregation.

    PubMed

    Luong, Lien T; Vigliotti, Beth A; Hudson, Peter J

    2011-04-01

    The vast majority of parasites exhibit an aggregated frequency distribution within their host population, such that most hosts have few or no parasites while only a minority of hosts are heavily infected. One exception to this rule is the trophically transmitted parasite Pterygodermatites peromysci of the white-footed mouse (Peromyscus leucopus), which is randomly distributed within its host population. Here, we ask: what are the factors generating the random distribution of parasites in this system when the majority of macroparasites exhibit non-random patterns? We hypothesise that tight density-dependent processes constrain parasite establishment and survival, preventing the build-up of parasites within individual hosts, and preclude aggregation within the host population. We first conducted primary infections in a laboratory experiment using white-footed mice to test for density-dependent parasite establishment and survival of adult worms. Secondary or challenge infection experiments were then conducted to investigate underlying mechanisms, including intra-specific competition and host-mediated restrictions (i.e. acquired immunity). The results of our experimental infections show a dose-dependent constraint on within-host-parasite establishment, such that the proportion of mice infected rose initially with exposure, and then dropped off at the highest dose. Additional evidence of density-dependent competition comes from the decrease in worm length with increasing levels of exposure. In the challenge infection experiment, previous exposure to parasites resulted in a lower prevalence and intensity of infection compared with primary infection of naïve mice; the magnitude of this effect was also density-dependent. Host immune response (IgG levels) increased with the level of exposure, but decreased with the number of worms established. Our results suggest that strong intra-specific competition and acquired host immunity operate in a density-dependent manner to

  7. The role of immunity in protection from mucosal SIV infection in macaques.

    PubMed

    Bergmeier, L A; Wang, Y; Lehner, T

    2002-01-01

    The need for an effective vaccine against HIV has prompted a refocusing of attention on mucosal immunity. More than 75% of all infections are acquired across a mucosal surface. It is therefore a prerequisite for a vaccine to target directly the mucosal tissues or indirectly the regional lymph nodes in order to prevent or control viral replication. Although mucosal immunization has induced responses at the genital or rectal surfaces, immune mechanisms alone have not been shown to be sufficient to contain infections in macaques. A growing body of evidence suggests that a dual mechanism may be required for effective mucosal protection, mediated by specific CD4 and CD8 T cell and antibody responses to the immunizing agents, plus innate antiviral factors and beta chemokines that down-regulate CCR5 coreceptors. Targeted iliac lymph node immunization with SIV gp 120 and p27 in alum prevents SIV infection or significantly decreases the viral load when immunized macaques were challenged with SIV by the rectal route. Indeed, in addition to specific immunity, including significant SIgA antibody secreting cells in the iliac lymph nodes, CD8-suppressor factor and the 3beta chemokines (RANTES, MIP-1alpha and MIP-1beta) are significantly associated with protection against rectal mucosal SIV infection.

  8. Proteins of Leishmania (Viannia) shawi confer protection associated with Th1 immune response and memory generation

    PubMed Central

    2012-01-01

    Background Leishmania (Viannia) shawi parasite was first characterized in 1989. Recently the protective effects of soluble leishmanial antigen (SLA) from L. (V.) shawi promastigotes were demonstrated using BALB/c mice, the susceptibility model for this parasite. In order to identify protective fractions, SLA was fractionated by reverse phase HPLC and five antigenic fractions were obtained. Methods F1 fraction was purified from L. (V.) shawi parasite extract by reverse phase HPLC. BALB/c mice were immunized once a week for two consecutive weeks by subcutaneous routes in the rump, using 25 μg of F1. After 1 and 16 weeks of last immunization, groups were challenged in the footpad with L. (V.) shawi promastigotes. After 2 months, those same mice were sacrificed and parasite burden, cellular and humoral immune responses were evaluated. Results The F1 fraction induced a high degree of protection associated with an increase in IFN-γ, a decrease in IL-4, increased cell proliferation and activation of CD8+T lymphocytes. Long-term protection was acquired in F1-immunized mice, associated with increased CD4+ central memory T lymphocytes and activation of both CD4+ and CD8+ T cells. In addition, F1-immunized groups showed an increase in IgG2a levels. Conclusions The inductor capability of antigens to generate memory lymphocytes that can proliferate and secrete beneficial cytokines upon infection could be an important factor in the development of vaccine candidates against American Tegumentary Leishmaniasis. PMID:22463817

  9. Social capital of Iranian patients living with acquired immune deficiency syndrome and associated factors.

    PubMed

    Ansari, S K; Nedjat, S; Jabbari, H; Saiepour, N; Heris, M J

    2015-12-13

    This study investigated the social capital of Iranian patients living with acquired immune deficiency syndrome (AIDS) and the associated factors. In a cross-sectional study the Integrated Social Capital Questionnaire was filled by a sequential sample of 300 patients visiting a referral counselling centre in Tehran. The patients' social capital scores were around 50% in the trust, social cohesion, collective action and cooperation and political empowerment domains. The groups and networks membership domain scored the lowest (27.1%). In regression analysis, employment status was significantly associated with groups and networks membership; age, marital status and financial status were associated with collective action and cooperation; period of disease awareness and marital status affected social cohesion and inclusion; and having risky behaviour affected empowerment and political action. Efforts are needed to enhance the social capital of those patients living with AIDS who are younger, unemployed, divorced/widowed, with risky behaviours and shorter disease awareness.

  10. Intraspleen DNA inoculation elicits protective cellular immune responses.

    PubMed

    Cano, A; Fragoso, G; Gevorkian, G; Terrazas, L I; Petrossian, P; Govezensky, T; Sciutto, E; Manoutcharian, K

    2001-04-01

    DNA immunization or inoculation is a recent vaccination method that induces both humoral and cellular immune responses in a range of hosts. Independent of the route or site of vaccination, the transfer of antigen-presenting cells (APC) or antigens into lymphoid organs is necessary. The aim of this investigation was to test whether intraspleen (i.s.) DNA inoculation is capable of inducing a protective immune response. We immunized mice by a single i.s. injection of a DNA construct expressing the immunoglobulin (Ig) heavy-chain variable domain (VH) in which the complementarity-determining regions (CDR) had been replaced by a Taenia crassiceps T-cell epitope. In these mice, immune responses and protective effects elicited by the vaccine were measured. We have shown here for the first time that i.s. DNA inoculation can induce protective cellular immune responses and activate CD8(+) T cells. Also, Ig V(H) appeared to be the minimal delivery unit of "antigenized" Ig capable of inducing T-cell activation in a lymphoid organ. The strategy of introducing T-cell epitopes into the molecular context of the V(H) domain in combination with i.s. DNA immunization could have important implications and applications for human immunotherapy.

  11. Herd immunity acquired indirectly from interactions between the ecology of infectious diseases, demography and economics.

    PubMed

    Bonds, Matthew H; Rohani, Pejman

    2010-03-01

    Patterns of morbidity and mortality around the globe are determined by interactions between infectious diseases and systematic human socioeconomic processes. The most obvious of these patterns is that the greatest burdens of infectious diseases are found among the poor, who lack the basic resources for disease prevention and treatment. Yet, it is becoming increasingly clear that many infectious diseases are themselves causes of poverty owing to their effects on labour productivity. A particularly subtle phenomenon that receives little attention in the epidemiology literature and is especially important for poor communities is the role of the birth rate as an important direct cause of high disease burdens. Because of their high rates of transmission and life-long immunity, the persistence of many child diseases such as measles relies on high rates of reproduction as their source of susceptible individuals. Thus, there are significant direct health benefits of lower fertility rates, which are further enhanced by interactions with economic processes. Indeed, fertility, poverty and disease all interact with each other in important and predictable ways that can be built into traditional disease ecology models. We present such a model here that provides insights into the long-term effect of policy interventions. For example, because of indirect income effects, herd immunity may be acquired with lower vaccine coverage than previously thought. Reductions in the disease burden can also occur through lower fertility. Our model thus provides a disease ecology framework that is useful for the analysis of demographic transitions.

  12. Effectiveness and safety of traditional Chinese medicine in treating acquired immune deficiency syndrome: 2004-2014.

    PubMed

    Liu, Zhi-Bin; Yang, Ji-Ping; Xu, Li-Ran

    2015-12-23

    Substantial progress has been made in China in using traditional Chinese medicine (TCM) to treat acquired immune deficiency syndrome (AIDS). Our objective was to review the latest developments in TCM treatment of AIDS in China between 2004 and 2014. We reviewed the content of original articles investigating the efficacy and safety of TCM for treating AIDS published in Chinese and English language journals. Relevant references from 2004 to 2014 were found using PubMed and the China National Knowledge Infrastructure Database. We found that TCM has been widely used for treating AIDS and its complications in China. The number of TCM studies has increased, which indicates efficacy and safety. Measures of efficacy in the reviewed articles included the alleviation of human immunodeficiency virus (HIV)-related signs and symptoms, improvements in quality of life, improvements in long-term survival, counteraction of the adverse side effects of antiviral drugs, promotion of immune reconstitution, and improvement of laboratory results. In sum, the literature indicates that TCM is safe. TCM plays an important role in the treatment of AIDS. Some studies have attempted to measure the efficacy and safety of TCM for treating AIDS, but more evidence is needed. Therefore, more research on this topic is required in the future.

  13. Development of Acquired Immunity following Repeated Respiratory Syncytial Virus Infections in Cotton Rats.

    PubMed

    Yamaji, Yoshiaki; Yasui, Yosuke; Nakayama, Tetsuo

    2016-01-01

    Respiratory syncytial virus (RSV) infections occur every year worldwide. Most infants are infected with RSV by one year of age and are reinfected because immune responses after the first infection are too weak to protect against subsequent infections. In the present study, immune responses against RSV were investigated in order to obtain a better understanding of repetitive RSV infections in cotton rats. No detectable neutralizing antibody (NT) was developed after the first infection, and the second infection was not prevented. The results of histological examinations revealed severe inflammation, viral antigens were detected around bronchial epithelial cells, and infectious viruses were recovered from lung homogenates. Following the second infection neutralizing antibodies were significantly elevated, and CD8+ cells were activated in response to RSV-F253-265. No viral antigens was detected thereafter in lung tissues and infectious viruses were not recovered. Similar results were obtained in the present study using the subgroups A and B. These results support the induction of humoral and cellular immune responses following repetitive infections with RSV; however, these responses were insufficient to eliminate viruses in the first and second infections. PMID:27224021

  14. Immunization of pregnant women: Future of early infant protection

    PubMed Central

    Faucette, Azure N; Pawlitz, Michael D; Pei, Bo; Yao, Fayi; Chen, Kang

    2015-01-01

    Children in early infancy do not mount effective antibody responses to many vaccines against commons infectious pathogens, which results in a window of increased susceptibility or severity infections. In addition, vaccine-preventable infections are among the leading causes of morbidity in pregnant women. Immunization during pregnancy can generate maternal immune protection as well as elicit the production and transfer of antibodies cross the placenta and via breastfeeding to provide early infant protection. Several successful vaccines are now recommended to all pregnant women worldwide. However, significant gaps exist in our understanding of the efficacy and safety of other vaccines and in women with conditions associated with increased susceptible to high-risk pregnancies. Public acceptance of maternal immunization remained to be improved. Broader success of maternal immunization will rely on the integration of advances in basic science in vaccine design and evaluation and carefully planned clinical trials that are inclusive to pregnant women. PMID:26366844

  15. Proposed method for agglutinating antibody titer analysis and its use as indicator of acquired immunity in pacu, Piaractus mesopotamicus.

    PubMed

    Biller-Takahashi, J D; Montassier, H J; Takahashi, L S; Urbinati, E C

    2014-02-01

    Antibody can be assessed by agglutinating antibody titer which is a quantitative measure of circulating antibodies in serum from fish previously immunized. The antibody evaluation has been performed with different fish species, and is considered a reliable method that can be applied to confirm several hypothesis regarding acquired immunity, even in conjunction with precise methods to describe immune mechanisms. In order to provide appropriate analytical methods for future studies on the specific immune system of native fish, the present study standardized on assay to measure the serum agglutinating antibody titer produced after immunization with inactivated A. hydrophila and levamisole administration in pacu. It was possible to determine the agglutinating antibodies titer in a satisfactorily way in pacu immunized with inactive A. hydrophila, and the highest titers were observed on fish fed with levamisole.

  16. Trachoma: Protective and Pathogenic Ocular Immune Responses to Chlamydia trachomatis

    PubMed Central

    Hu, Victor H.; Holland, Martin J.; Burton, Matthew J.

    2013-01-01

    Trachoma, caused by Chlamydia trachomatis (Ct), is the leading infectious blinding disease worldwide. Chronic conjunctival inflammation develops in childhood and leads to eyelid scarring and blindness in adulthood. The immune response to Ct provides only partial protection against re-infection, which can be frequent. Moreover, the immune response is central to the development of scarring pathology, leading to loss of vision. Here we review the current literature on both protective and pathological immune responses in trachoma. The resolution of Ct infection in animal models is IFNγ-dependent, involving Th1 cells, but whether this is the case in human ocular infection still needs to be confirmed. An increasing number of studies indicate that innate immune responses arising from the epithelium and other innate immune cells, along with changes in matrix metalloproteinase activity, are important in the development of tissue damage and scarring. Current trachoma control measures, which are centred on repeated mass antibiotic treatment of populations, are logistically challenging and have the potential to drive antimicrobial resistance. A trachoma vaccine would offer significant advantages. However, limited understanding of the mechanisms of both protective immunity and immunopathology to Ct remain barriers to vaccine development. PMID:23457650

  17. Staphylococcal biofilm exopolysaccharide protects against Caenorhabditis elegans immune defenses.

    PubMed

    Begun, Jakob; Gaiani, Jessica M; Rohde, Holger; Mack, Dietrich; Calderwood, Stephen B; Ausubel, Frederick M; Sifri, Costi D

    2007-04-01

    Staphylococcus epidermidis and Staphylococcus aureus are leading causes of hospital-acquired infections that have become increasingly difficult to treat due to the prevalence of antibiotic resistance in these organisms. The ability of staphylococci to produce biofilm is an important virulence mechanism that allows bacteria both to adhere to living and artificial surfaces and to resist host immune factors and antibiotics. Here, we show that the icaADBC locus, which synthesizes the biofilm-associated polysaccharide intercellular adhesin (PIA) in staphylococci, is required for the formation of a lethal S. epidermidis infection in the intestine of the model nematode Caenorhabditis elegans. Susceptibility to S. epidermidis infection is influenced by mutation of the C. elegans PMK-1 p38 mitogen-activated protein (MAP) kinase or DAF-2 insulin-signaling pathways. Loss of PIA production abrogates nematocidal activity and leads to reduced bacterial accumulation in the C. elegans intestine, while overexpression of the icaADBC locus in S. aureus augments virulence towards nematodes. PIA-producing S. epidermidis has a significant survival advantage over ica-deficient S. epidermidis within the intestinal tract of wild-type C. elegans, but not in immunocompromised nematodes harboring a loss-of-function mutation in the p38 MAP kinase pathway gene sek-1. Moreover, sek-1 and pmk-1 mutants are equally sensitive to wild-type and icaADBC-deficient S. epidermidis. These results suggest that biofilm exopolysaccharide enhances virulence by playing an immunoprotective role during colonization of the C. elegans intestine. These studies demonstrate that C. elegans can serve as a simple animal model for studying host-pathogen interactions involving staphylococcal biofilm exopolysaccharide and suggest that the protective activity of biofilm matrix represents an ancient conserved function for resisting predation.

  18. The effect of route of immunization on mucosal immunity and protection.

    PubMed

    Lehner, T; Wang, Y; Ping, L; Bergmeier, L; Mitchell, E; Cranage, M; Hall, G; Dennis, M; Cook, N; Doyle, C; Jones, I

    1999-05-01

    In macaques, the route of immunization has a profound effect on the immune response. Augmenting rectal or vaginal immunization with oral or nasal immunization enhanced the secretory IgA, serum IgG, and T cell responses. However, targeted iliac lymph node (TILN) immunization with recombinant simian immunodeficiency virus (SIV) gp120 and p27 elicited the most consistent mucosal antibody responses in the rectum, vagina, urine, seminal fluid, and blood. Both mucosal and TILN immunization induced specific CD4+ T cell proliferative responses in the iliac lymph nodes, which drain these mucosal surfaces, and in the splenic and circulating T cells. Rectal mucosal challenge with cell-free SIV induced total protection in 4 of 7 macaques that were immunized by the TILN route, and, compared with unimmunized macaques or those immunized by the mucosal route (P<.001), it induced a >90% decrease in virus load in 3 of them. Protection from mucosal rectal infection with SIV was significantly associated with an increase in the CD8 suppressor factor (which was generated by the iliac lymph node), RANTES, and MIP-1beta (P<.01).

  19. Effective immune protection of pigs against cysticercosis.

    PubMed

    Nascimento, E; Costa, J O; Guimarães, M P; Tavares, C A

    1995-03-01

    A scolex protein antigen (SPA) was prepared from cysticerci of Taenia solium obtained from naturally infected pigs. Yorkshire pigs were vaccinated with SPA plus incomplete Freund's adjuvant (IFA) or with SPA plus Corynebacterium parvum (CP). Controls were given IFA plus phosphate-buffered saline (PBS) or CP plus PBS. All animals were given three subcutaneous injections at 20-day intervals. Ten days after the third injection, the pigs were fed with 10(4) viable eggs of T. solium. All pigs developed a delayed type hypersensitivity, and a transient eosinophilia after the first dose of vaccine. High titers of specific antibodies were detected in the sera of vaccinated animals and in infected controls. A protection level of 71.43% was recorded in animals vaccinated with SPA plus IFA and of 75.00% in those vaccinated with SPA plus CP.

  20. Effective immune protection of pigs against cysticercosis.

    PubMed

    Nascimento, E; Costa, J O; Guimarães, M P; Tavares, C A

    1995-03-01

    A scolex protein antigen (SPA) was prepared from cysticerci of Taenia solium obtained from naturally infected pigs. Yorkshire pigs were vaccinated with SPA plus incomplete Freund's adjuvant (IFA) or with SPA plus Corynebacterium parvum (CP). Controls were given IFA plus phosphate-buffered saline (PBS) or CP plus PBS. All animals were given three subcutaneous injections at 20-day intervals. Ten days after the third injection, the pigs were fed with 10(4) viable eggs of T. solium. All pigs developed a delayed type hypersensitivity, and a transient eosinophilia after the first dose of vaccine. High titers of specific antibodies were detected in the sera of vaccinated animals and in infected controls. A protection level of 71.43% was recorded in animals vaccinated with SPA plus IFA and of 75.00% in those vaccinated with SPA plus CP. PMID:7604530

  1. Changes in cytokine production associated with acquired immunity to Plasmodium falciparum malaria

    PubMed Central

    Rhee, M S M; Akanmori, B D; Waterfall, M; Riley, E M

    2001-01-01

    Individuals living in malaria-endemic areas eventually develop clinical immunity to Plasmodium falciparum. That is, they are able to limit blood parasite densities to extremely low levels and fail to show symptoms of infection. As the clinical symptoms of malaria infection are mediated in part by pro-inflammatory cytokines it is not clear whether the acquisition of clinical immunity is due simply to the development of antiparasitic mechanisms or whether the ability to regulate inflammatory cytokine production is also involved. We hypothesize that there is a correlation between risk of developing clinical malaria and the tendency to produce high levels of proinflammatory cytokines in response to malaria infection. In order to test this hypothesis, we have compared the ability of peripheral blood mononuclear cells from malaria-naive and malaria-exposed adult donors to proliferate and to secrete IFN-γ in response to P. falciparum schizont extract (PfSE). In order to determine how PfSE-induced IFN-γ production is regulated, we have also measured production of IL-12p40 and IL-10 from PfSE-stimulated PBMC and investigated the role of neutralizing antibody to IL-12 in modulating IFN-γ production. We find that cells from naive donors produce moderate amounts of IFN-γ in response to PfSE and that IFN-γ production is strongly IL-12 dependent. Cells from malaria-exposed donors living in an area of low malaria endemicity produce much higher levels of IFN-γ and this response is also at least partially IL-12 dependent. In complete contrast, cells from donors living in an area of very high endemicity produce minimal amounts of IFN-γ. No significant differences were detected between the groups in IL-10 production, suggesting that this cytokine does not play a major role in regulating malaria-induced IFN-γ production. The data from this study thus strongly support the hypothesis that down-regulation of inflammatory cytokine production may be a component of acquired clinical

  2. Immunization

    MedlinePlus

    ... a lot worse. Some are even life-threatening. Immunization shots, or vaccinations, are essential. They protect against things like measles, ... B, polio, tetanus, diphtheria, and pertussis (whooping cough). Immunizations are important for adults as well as children. ...

  3. Rational design of a meningococcal antigen inducing broad protective immunity.

    PubMed

    Scarselli, Maria; Aricò, Beatrice; Brunelli, Brunella; Savino, Silvana; Di Marcello, Federica; Palumbo, Emmanuelle; Veggi, Daniele; Ciucchi, Laura; Cartocci, Elena; Bottomley, Matthew James; Malito, Enrico; Lo Surdo, Paola; Comanducci, Maurizio; Giuliani, Marzia Monica; Cantini, Francesca; Dragonetti, Sara; Colaprico, Annalisa; Doro, Francesco; Giannetti, Patrizia; Pallaoro, Michele; Brogioni, Barbara; Tontini, Marta; Hilleringmann, Markus; Nardi-Dei, Vincenzo; Banci, Lucia; Pizza, Mariagrazia; Rappuoli, Rino

    2011-07-13

    The sequence variability of protective antigens is a major challenge to the development of vaccines. For Neisseria meningitidis, the bacterial pathogen that causes meningitis, the amino acid sequence of the protective antigen factor H binding protein (fHBP) has more than 300 variations. These sequence differences can be classified into three distinct groups of antigenic variants that do not induce cross-protective immunity. Our goal was to generate a single antigen that would induce immunity against all known sequence variants of N. meningitidis. To achieve this, we rationally designed, expressed, and purified 54 different mutants of fHBP and tested them in mice for the induction of protective immunity. We identified and determined the crystal structure of a lead chimeric antigen that was able to induce high levels of cross-protective antibodies in mice against all variant strains tested. The new fHBP antigen had a conserved backbone that carried an engineered surface containing specificities for all three variant groups. We demonstrate that the structure-based design of multiple immunodominant antigenic surfaces on a single protein scaffold is possible and represents an effective way to create broadly protective vaccines.

  4. Predictive factors for the Nursing Diagnoses in people living with Acquired Immune Deficiency Syndrome 1

    PubMed Central

    da Silva, Richardson Augusto Rosendo; Costa, Romanniny Hévillyn Silva; Nelson, Ana Raquel Cortês; Duarte, Fernando Hiago da Silva; Prado, Nanete Caroline da Costa; Rodrigues, Eduardo Henrique Fagundes

    2016-01-01

    Abstract Objective: to identify the predictive factors for the nursing diagnoses in people living with Acquired Immune Deficiency Syndrome. Method: a cross-sectional study, undertaken with 113 people living with AIDS. The data were collected using an interview script and physical examination. Logistic regression was used for the data analysis, considering a level of significance of 10%. Results: the predictive factors identified were: for the nursing diagnosis of knowledge deficit-inadequate following of instructions and verbalization of the problem; for the nursing diagnosis of failure to adhere - years of study, behavior indicative of failure to adhere, participation in the treatment and forgetfulness; for the nursing diagnosis of sexual dysfunction - family income, reduced frequency of sexual practice, perceived deficit in sexual desire, perceived limitations imposed by the disease and altered body function. Conclusion: the predictive factors for these nursing diagnoses involved sociodemographic and clinical characteristics, defining characteristics, and related factors, which must be taken into consideration during the assistance provided by the nurse. PMID:27384466

  5. The role of spatial population structure on the evolution of parasites with acquired immunity and demography.

    PubMed

    Webb, Steven D; Keeling, Matt J; Boots, Mike

    2013-05-01

    It is clear that the evolution of infectious disease may be influenced by population spatial structure and transmission networks but we lack an understanding of the role of acquired immunity. Here we examine theoretically the role of spatial structure in the evolution of infectious disease described by the classic Susceptible, Infected, Recovered (SIR) model focusing on the impact of host demographics. We find that, for the classic assumption of a trade-off between transmission and virulence, localised transmission does favor, as predicted from other models, chronic pathogens with low transmission and virulence, but that this effect reduces as the recovery rate increases. However, under the assumption that pathogens reproduce rapidly within the host are harder to clear but result in higher virulence local interactions favor more virulent parasites and, depending on the nature of the disease interaction, can increase or decrease the chance of evolutionary bistabilities that may lead to sudden persistent changes in virulence. Therefore, our work further emphasizes the importance of spatial structure to parasite evolution. This spatial evolutionary theory is important because it predicts how different pathogens may respond to changes in patterns of mixing.

  6. The keys of oxidative stress in acquired immune deficiency syndrome apoptosis.

    PubMed

    Romero-Alvira, D; Roche, E

    1998-08-01

    Apoptosis is the main cause of CD4+ T-lymphocyte depletion in acquired immune deficiency syndrome (AIDS). Various agents appear to be able to trigger apoptosis in CD4+ T cells, including viral proteins (i.e. gp120, Tat), inappropriate secretion of inflammatory cytokines by activated macrophages (i.e. tumor necrosis factor alpha) and toxins produced by opportunistic micro-organisms. Since oxidative stress can also induce apoptosis, it can be hypothesized that such a mechanism could participate in CD4+ T-cell apoptosis observed in AIDS. This correlates strongly with the observation that AIDS patients present low levels of antioxidants (i.e. superoxide dismutase-Mn, vitamin E, selenium and glutathion) most likely due to inappropriate nutrition (i.e. diets poor in antioxidants), alcohol and drug consumption, and digestive problems associated with the disease. Furthermore, the coadministration of the antiviral drug zidovudine with antioxidants increases its therapeutic potential. Finally, the following additional observations support the hypothesis that oxidative stress is involved in cell apoptosis in AIDS: (1) The depletion of the anti-apoptotic/antioxidant protein Bcl-2 in human immunodeficiency virus (HIV)-infected CD4+ cells; (2) a decrease of apoptosis in HIV-infected cells treated with antioxidants and; (3) the presence of the pro-apoptotic/pro-oxidant cytokines secreted by activated macrophages in AIDS patients. Therefore, anti-apoptotic/antioxidant strategies should be considered, alongside antiviral strategies, in order to design a more efficient therapy for AIDS in the near future.

  7. Coping Strategies of Patients with Haemophilia as a Risk Group for AIDS (Acquired Immune Deficiency Syndrome). Brief Research Report.

    ERIC Educational Resources Information Center

    Naji, Simon; And Others

    1986-01-01

    Plans are described for a 2-year project whose major focus is the identification of ways in which patients with hemophilia and their families assimilate, interpret, and act on information about Acquired Immune Deficiency Syndrome (AIDS). Findings will be related to perceived risk, anxiety levels, and the development of coping strategies.…

  8. AIDS: Acquired Immune Deficiency Syndrome; Information and Procedural Guidelines for Providing Services to Persons with AIDS/HIV. Revised.

    ERIC Educational Resources Information Center

    Montana State Dept. of Health and Environmental Sciences, Helena. Health Education Bureau.

    This volume consists of updated information to be inserted into a Montana AIDS Project manual on providing services to persons with acquired immune deficiency syndrome/human immunodeficiency virus (AIDS/HIV), originally published in December 1985. The updates are mainly statistics and terminology, along with the addition of several new sections.…

  9. AIDS: Acquired Immune Deficiency Syndrome, Information and Procedural Guidelines for Providing Services to Persons with AIDS/HTLV-III.

    ERIC Educational Resources Information Center

    Montana State Dept. of Health and Environmental Sciences, Helena.

    This manual presents information about the disease, Acquired Immune Deficiency Syndrome (AIDS), and guidelines for service delivery to Montana residents who have been diagnosed with AIDS or related disorders. The first section describes the disease's causes, symptoms, and transmission; risk factors; high-risk populations; prevention suggestions;…

  10. Select Personality Characteristic Differences between Caregivers for Persons with Acquired Immune Deficiency Syndrome and Caregivers for Other Types of Illness.

    ERIC Educational Resources Information Center

    Angel, Daniel Scott; Heritage, Jeannette

    The purpose of this study was to analyze select personality characteristics of individuals working within the Acquired Immune Deficiency Syndrome (AIDS) population in comparison to non-AIDS caregivers by using two personality assessment instruments. Subjects were from two health care provider populations. Two hundred research packets were…

  11. Hepatitis E virus: neutralizing sites, diagnosis, and protective immunity.

    PubMed

    Zhang, Jun; Li, Shao-Wei; Wu, Ting; Zhao, Qinjian; Ng, Mun-Hon; Xia, Ning-Shao

    2012-09-01

    There have been increased attentions on HEV and its associated diseases in recent years as a result of an increased number of reports on autochthonous patients from many developed countries. Vaccine development and better disease management are expected from protective immunity with increased knowledge on the pathogenesis and virology of HEV. This review summarizes the current understanding of the HEV virology, the key neutralization sites (epitopes) on the surface of the viral capsid, the host humoral immune responses for HEV infection, and the protective immunity conferred by natural infection and vaccination. Recombinant VLPs were prepared to mimic the protective and neutralizing epitopes on the virion surface, thus being capable of eliciting protective immunity when injected to nonhuman primates or human volunteers during preclinical tests and clinical trials. Four markers-viral RNA, anti-HEV IgM, anti-HEV IgG, and low avidity of anti-HEV IgG-are important in the diagnosis of HEV infection, particularly for patients presenting with acute hepatitis symptoms. This toolbox of genomic and immunological assays is valuable in furthering our understanding of the time course of HEV infection and the subsequent hepatitis during preclinical and clinical development of an efficacious vaccine. Two vaccine candidates had shown good tolerability, high immunogenicity, and high efficacy against symptomatic and/or asymptomatic HEV infection. One of them has been licensed in China recently. However, many issues need to be resolved before new technological progresses can benefit the people who need them most. PMID:22645002

  12. Immune Responses and Protection of Aotus Monkeys Immunized with Irradiated Plasmodium vivax Sporozoites

    PubMed Central

    Jordán-Villegas, Alejandro; Perdomo, Anilza Bonelo; Epstein, Judith E.; López, Jesús; Castellanos, Alejandro; Manzano, María R.; Hernández, Miguel A.; Soto, Liliana; Méndez, Fabián; Richie, Thomas L.; Hoffman, Stephen L.; Arévalo-Herrera, Myriam; Herrera, Sócrates

    2011-01-01

    A non-human primate model for the induction of protective immunity against the pre-erythrocytic stages of Plasmodium vivax malaria using radiation-attenuated P. vivax sporozoites may help to characterize protective immune mechanisms and identify novel malaria vaccine candidates. Immune responses and protective efficacy induced by vaccination with irradiated P. vivax sporozoites were evaluated in malaria-naive Aotus monkeys. Three groups of six monkeys received two, five, or ten intravenous inoculations, respectively, of 100,000 irradiated P. vivax sporozoites; control groups received either 10 doses of uninfected salivary gland extract or no inoculations. Immunization resulted in the production low levels of antibodies that specifically recognized P. vivax sporozoites and the circumsporozoite protein. Additionally, immunization induced low levels of antigen-specific IFN-γ responses. Intravenous challenge with viable sporozoites resulted in partial protection in a dose-dependent manner. These findings suggest that the Aotus monkey model may be able to play a role in preclinical development of P. vivax pre-erythrocytic stage vaccines. PMID:21292877

  13. Effects of dietary fish meal and soybean meal on the ovine innate and acquired immune response during pregnancy and lactation.

    PubMed

    Stryker, J A; Fisher, R; You, Q; Or-Rashid, M M; Boermans, H J; Quinton, M; McBride, B W; Karrow, N A

    2013-01-01

    In recent years, livestock producers have been supplementing animal diets with fish meal (FM) to produce value-added products for health conscious consumers. As components of FM have unique neuroendocrine-immunomodulatory properties, we hypothesize that livestock producers may be influencing the overall health of their animals by supplementing diets with FM. In this study, 40 pregnant ewes were supplemented with rumen protected (RP) soybean meal (SBM: control diet) or RP FM, commencing gestation day 100 (gd100), in order to evaluate the impact of FM supplementation on the innate and acquired immune response and neuroendocrine response of sheep during pregnancy and lactation. On gd135, half the ewes from each diet (n = 10 FM, n = 10 SBM) were challenged iv with lipopolysaccharide (LPS) to simulate a systemic bacterial infection and the febrile, respiratory and neuroendocrine responses were monitored over time; the other half (n = 10 FM, n = 10 SBM) of the ewes received a saline injection as control. On lactation day 20 (ld20), all ewes (n = 20 FM, n = 20 SBM) were sensitized with hen egg white lysozyme (HEWL) and the serum haptoglobin (Hp) response was measured over time. The cutaneous hypersensitivity response (CHR) to HEWL challenge was measured on ld30 (n = 20 FM, n = 20 SBM), and blood samples were collected over time to measure the primary and secondary immunoglobulin G (IgG) response to HEWL. There was an attenuated trend in the LPS-induced febrile response by the FM treatment when compared with the SBM treatment (P = 0.06), as was also true for the respiratory response (P = 0.07), but significant differences in neuroendocrine function (serum cortisol and plasma ACTH) were not observed between treatments. Basal Hp levels were significantly lower in the FM supplemented ewes when compared with the SBM supplemented ewes (P < 0.01), and the Hp response to HEWL sensitization differed significantly over time between treatments (P < 0.01). The CHR to HEWL was also

  14. Effects of anti-schistosomal chemotherapy on immune responses, protection and immunity. II. Concomitant immunity and immunization with irradiated cercariae

    SciTech Connect

    Tawfik, A.F.; Colley, D.G.

    1986-01-01

    Resistance of mice to challenge infections of Schistosoma mansoni was evaluated before and after elimination of their primary, established S. mansoni infections with the chemotherapeutic drug praziquantel. Mice treated after either 10 or 20 weeks of primary infection were challenged 6 or 10 weeks after treatment. Mice infected for for 10 weeks prior to treatment expressed progressively less resistance 6 and 10 weeks after treatment. By 10 weeks after treatment significant levels of protection were no longer observed. Resistance waned more slowly if mice were treated 20 weeks after infection, and there was still significant expression of resistance to challenge 10 weeks after treatment. A separate set of experiments evaluated the use of highly irradiated cercariae as a vaccine in mice that had been previously infected with S. mansoni and cured with praziquantel. It was observed that effective immunizations were possible in previously infected mice. These studies demonstrate that established resistance waned after treatment and the rate of loss of protection was dependent upon the duration of infection prior to treatment. Furthermore, the irradiated cercarial vaccine studies indicate that in the murine model induction of immunological resistance was feasible following chemotherapeutic treatment of infected populations.

  15. Protective and pathologic immune responses against Candida albicans infection.

    PubMed

    Ashman, Robert B

    2008-05-01

    Candida albicans is an important opportunistic fungal pathogen. Clinical observations have indicated that both innate and adaptive immune responses are involved in recovery from initial infection, but analysis in murine models has shown that the contribution of the two arms of the cellular immune response differ in oral, vaginal, and systemic infections. The relative contributions of T cells and phagocytic cells, and the cytokines that mediate their interactions are discussed for each of the different manifestations of the disease, and the consequences of infection, in terms of protection and pathology, are evaluated.

  16. Functions of innate and acquired immune system are reduced in domestic pigeons (Columba livia domestica) given a low protein diet

    PubMed Central

    Mabuchi, Yuko; Frankel, Theresa L.

    2016-01-01

    Racing pigeons are exposed to and act as carriers of diseases. Dietary protein requirement for their maintenance has not been determined experimentally despite their being domesticated for over 7000 years. A maintenance nitrogen (protein) requirement (MNR) for pigeons was determined in a balance study using diets containing 6, 10 and 14% crude protein (CP). Then, the effects of feeding the diets were investigated to determine whether they were adequate to sustain innate and acquired immune functions. Nitrogen intake from the 6% CP diet was sufficient to maintain nitrogen balance and body weight in pigeons. However, the immune functions of phagocytosis, oxidative burst and lymphocyte proliferation in pigeons fed this diet were reduced compared with those fed 10 and 14% CP diets. Pigeons given the 6 and 10% CP diets had lower antibody titres following inoculation against Newcastle disease (ND) than those on the 14% CP diet. A confounding factor found on autopsy was the presence of intestinal parasites in some of the pigeons given the 6 and 10% CP diets; however, none of the pigeons used to measure MNR or acquired immunity to ND were infested with parasites. In conclusion, neither the 6 nor 10% CP diets adequately sustained acquired immune function of pigeons. PMID:27069640

  17. Functions of innate and acquired immune system are reduced in domestic pigeons (Columba livia domestica) given a low protein diet.

    PubMed

    Mabuchi, Yuko; Frankel, Theresa L

    2016-03-01

    Racing pigeons are exposed to and act as carriers of diseases. Dietary protein requirement for their maintenance has not been determined experimentally despite their being domesticated for over 7000 years. A maintenance nitrogen (protein) requirement (MNR) for pigeons was determined in a balance study using diets containing 6, 10 and 14% crude protein (CP). Then, the effects of feeding the diets were investigated to determine whether they were adequate to sustain innate and acquired immune functions. Nitrogen intake from the 6% CP diet was sufficient to maintain nitrogen balance and body weight in pigeons. However, the immune functions of phagocytosis, oxidative burst and lymphocyte proliferation in pigeons fed this diet were reduced compared with those fed 10 and 14% CP diets. Pigeons given the 6 and 10% CP diets had lower antibody titres following inoculation against Newcastle disease (ND) than those on the 14% CP diet. A confounding factor found on autopsy was the presence of intestinal parasites in some of the pigeons given the 6 and 10% CP diets; however, none of the pigeons used to measure MNR or acquired immunity to ND were infested with parasites. In conclusion, neither the 6 nor 10% CP diets adequately sustained acquired immune function of pigeons.

  18. Effect of bacillus Calmette-Guérin vaccination on CD4+Foxp3+ T cells during acquired immune response to Mycobacterium tuberculosis infection.

    PubMed

    Henao-Tamayo, Marcela I; Obregón-Henao, Andres; Arnett, Kimberly; Shanley, Crystal A; Podell, Brendan; Orme, Ian M; Ordway, Diane J

    2016-04-01

    Increasing information has shown that many newly emerging strains of Mycobacterium tuberculosis, including the highly prevalent and troublesome Beijing family of strains, can potently induce the emergence of Foxp3(+)CD4 Tregs Although the significance of this is still not fully understood, we have previously provided evidence that the emergence of this population can significantly ablate the protective effect of BCG vaccination, causing progressive fatal disease in the mouse model. However, whether the purpose of this response is to control inflammation or to directly dampen the acquired immune response is still unclear. In the present study, we have shown, using both cell depletion and adoptive transfer strategies, that Tregs can have either properties. Cell depletion resulted in a rapid, but transient, decrease in the lung bacterial load, suggesting release or temporary re-expansion of effector immunity. Transfer of Tregs into Rag2(-/-)or marked congenic mice worsened the disease course and depressed cellular influx of effector T cells into the lungs. Tregs from infected donors seemed to preferentially depress the inflammatory response and granulocytic influx. In contrast, those from BCG-vaccinated and then challenged donors seemed more focused on depression of acquired immunity. These qualitative differences might be related to increasing knowledge reflecting the plasticity of the Treg response.

  19. [Resistance to Naegleria fowleri infection passively acquired from immunized splenocyte, serum or milk].

    PubMed

    Ahn, M H; Min, D Y

    1989-06-01

    A pathogenic free-living amoeba, Naegleria fowleri, causes primary amoebic meningoencephalitis to human and experimental animals. This infection is rare, but the mortality is very high. Nowadays, drug treatment or active immunization of human or mice are being tried with partial effectiveness. This study shows passive immunization effect by transfer of immunized spleen cells, serum, or milk from immunized mother in mouse experimental model. Young BALB/c mice were immunized intraperitoneally with 2-3 X 10(6) trophozoites of N. fowleri, and spleen cells and sera were collected for injection to recipient mice. There were seven transfer groups, i.e., immunized mouse serum, spleen cells, serum and spleen cells, normal mouse serum, spleen cells, serum and spleen cells, and control group. Three days later, BALB/c mice were inoculated with 1 x 10(4) trophozoites of N. fowleri intranasally. After infection, decreased mortality and prolonged survival time of mice were noted in immunized groups compared with non-immunized control group. The groups injected with immunized spleen cells or normal serum showed lower mortality than that of controls but showed no changes of serum IgG level. The groups injected with immunized serum or normal spleen cells showed increased serum IgG level after immunization but hundred percent mortality was observed. Mother mice were immunized intraperitoneally with 2-3 X 10(6) trophozoites of N. fowleri at the end of pregnancy and weaning period. Soon after the delivery, litters born of non-immunized mother were matched with immunized mother for feeding immune milk. After three weeks, the litters were infected with 1 X 10(4) trophozoites of N. fowleri or sacrificed for serum collection to measure the IgG levels.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2486833

  20. [Resistance to Naegleria fowleri infection passively acquired from immunized splenocyte, serum or milk].

    PubMed

    Ahn, M H; Min, D Y

    1989-06-01

    A pathogenic free-living amoeba, Naegleria fowleri, causes primary amoebic meningoencephalitis to human and experimental animals. This infection is rare, but the mortality is very high. Nowadays, drug treatment or active immunization of human or mice are being tried with partial effectiveness. This study shows passive immunization effect by transfer of immunized spleen cells, serum, or milk from immunized mother in mouse experimental model. Young BALB/c mice were immunized intraperitoneally with 2-3 X 10(6) trophozoites of N. fowleri, and spleen cells and sera were collected for injection to recipient mice. There were seven transfer groups, i.e., immunized mouse serum, spleen cells, serum and spleen cells, normal mouse serum, spleen cells, serum and spleen cells, and control group. Three days later, BALB/c mice were inoculated with 1 x 10(4) trophozoites of N. fowleri intranasally. After infection, decreased mortality and prolonged survival time of mice were noted in immunized groups compared with non-immunized control group. The groups injected with immunized spleen cells or normal serum showed lower mortality than that of controls but showed no changes of serum IgG level. The groups injected with immunized serum or normal spleen cells showed increased serum IgG level after immunization but hundred percent mortality was observed. Mother mice were immunized intraperitoneally with 2-3 X 10(6) trophozoites of N. fowleri at the end of pregnancy and weaning period. Soon after the delivery, litters born of non-immunized mother were matched with immunized mother for feeding immune milk. After three weeks, the litters were infected with 1 X 10(4) trophozoites of N. fowleri or sacrificed for serum collection to measure the IgG levels.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Production and function of cytokines in natural and acquired immunity to Candida albicans infection.

    PubMed Central

    Ashman, R B; Papadimitriou, J M

    1995-01-01

    Host resistance against infections caused by the yeast Candida albicans is mediated predominantly by polymorphonuclear leukocytes and macrophages. Antigens of Candida stimulate lymphocyte proliferation and cytokine synthesis, and in both humans and mice, these cytokines enhance the candidacidal functions of the phagocytic cells. In systemic candidiasis in mice, cytokine production has been found to be a function of the CD4+ T helper (Th) cells. The Th1 subset of these cells, characterized by the production of gamma interferon and interleukin-2, is associated with macrophage activation and enhanced resistance against reinfection, whereas the Th2 subset, which produces interleukins-4, -6, and -10, is linked to the development of chronic disease. However, other models have generated divergent data. Mucosal infection generally elicits Th1-type cytokine responses and protection from systemic challenge, and identification of cytokine mRNA present in infected tissues of mice that develop mild or severe lesions does not show pure Th1- or Th2-type responses. Furthermore, antigens of C. albicans, mannan in particular, can induce suppressor cells that modulate both specific and nonspecific cellular and humoral immune responses, and there is an emerging body of evidence that molecular mimicry may affect the efficiency of anti-Candida responses within defined genetic contexts. PMID:8531890

  2. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice

    PubMed Central

    Lee, Pei Xuan; Ong, Li Ching; Libau, Eshele Anak; Alonso, Sylvie

    2016-01-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers. PMID:27341339

  3. Relative Contribution of Dengue IgG Antibodies Acquired during Gestation or Breastfeeding in Mediating Dengue Disease Enhancement and Protection in Type I Interferon Receptor-Deficient Mice.

    PubMed

    Lee, Pei Xuan; Ong, Li Ching; Libau, Eshele Anak; Alonso, Sylvie

    2016-06-01

    Dengue virus (DENV) causes a spectrum of diseases ranging from self-limiting dengue fever to severe conditions such as haemorrhagic fever and dengue shock syndrome. Antibody-dependent enhancement (ADE) is thought to explain the occurrence of severe dengue whereby pre-existing binding but non-neutralising antibodies enhance DENV infection. The ADE phenomenon is supported by epidemiological findings that infants that born to dengue immune mothers are at greater risk to develop severe dengue upon primary infection. The role of maternally acquired dengue-specific antibodies in disease enhancement was recently recapitulated in a mouse model where mice born to DENV1-immune mothers experienced enhanced disease severity upon DENV2 infection. Here, this study investigates the relative contribution of maternal dengue-specific antibodies acquired during gestation and breastfeeding in dengue disease. Using a surrogate breastfeeding mother experimental approach, we showed that majority of the maternal dengue-specific antibodies were acquired during breastfeeding and conferred an extended enhancement window. On the other hand, in the context of homologous infection, breastfeeding conferred protection. Furthermore, measurement of dengue-specific antibody titres over time in mice born to dengue immune mothers revealed a biphasic pattern of antibody decay as reported in humans. Our work provides evidence of the potential contribution of breast milk-acquired dengue-specific IgG antibodies in enhancement and protection against dengue. Should such contribution be established in humans as well, it may have important implications for the development of guidelines to dengue-immune breastfeeding mothers. PMID:27341339

  4. Schistosoma mansoni: is acquired immunity induced by highly x-irradiated cercariae dependent on the size of the challenging dose

    SciTech Connect

    Hsue, S.Y.; Hsue, H.F.; Osborne, J.W.; Johnson, S.C.

    1982-04-01

    A high degree of immunity, as shown by a 91% reduction of the number of worms recovered was found in five groups of mice that were immunized five times with highly X-irradiated cercariae and then challenged with 10, 20, 50, 100, or 500 normal Schistosoma mansoni cercariae. The results indicated that there were no significant differences in worm reduction in immunized mice challenged with different numbers of cercariae; consequently the immunity induced by this immunization method did not appear to be challenge-dose-dependent. However, the results also showed that when immunized mice were challenged with 500, 100, 50, 20, and 10 cercariae, 0, 13, 26, 56, and 68%, respectively, of the experimental animals were free of worms. Thus, the percentage of worm-negative cases increased as the number of challenge cercariae decreased. When viewed in this manner, the acquired immunity may be considered challenge-dose-dependent as well. If this method of vaccination is used for schistosomiasis control, we may anticipate that in both hypo- and hyperendemic areas, the intensity of infection and the severity of the disease will be reduced owing to a reduction in worms burdens, and in hypoendemic areas, there will be a number of worm-free cases.

  5. Protective MCMV immunity by vaccination of the salivary gland via Wharton's duct: replication-deficient recombinant adenovirus expressing individual MCMV genes elicits protection similar to that of MCMV.

    PubMed

    Liu, Guangliang; Zhang, Fangfang; Wang, Ruixue; London, Lucille; London, Steven D

    2014-04-01

    Salivary glands, a major component of the mucosal immune system, confer antigen-specific immunity to mucosally acquired pathogens. We investigated whether a physiological route of inoculation and a subunit vaccine approach elicited MCMV-specific and protective immunity. Mice were inoculated by retrograde perfusion of the submandibular salivary glands via Wharton's duct with tcMCMV or MCMV proteins focused to the salivary gland via replication-deficient adenovirus expressing individual MCMV genes (gB, gH, IE1; controls: saline and replication deficient adenovirus without MCMV inserts). Mice were evaluated for MCMV-specific antibodies, T-cell responses, germinal center formation, and protection against a lethal MCMV challenge. Retrograde perfusion with tcMCMV or adenovirus expressed MCMV proteins induced a 2- to 6-fold increase in systemic and mucosal MCMV-specific antibodies, a 3- to 6-fold increase in GC marker expression, and protection against a lethal systemic challenge, as evidenced by up to 80% increased survival, decreased splenic pathology, and decreased viral titers from 10(6) pfu to undetectable levels. Thus, a focused salivary gland immunization via a physiological route with a protein antigen induced systemic and mucosal protective immune responses. Therefore, salivary gland immunization can serve as an alternative mucosal route for administering vaccines, which is directly applicable for use in humans.

  6. Protective immunity spectrum induced by immunization with a vaccine from the TBEV strain Sofjin.

    PubMed

    Chernokhaeva, L L; Rogova, Yu V; Vorovitch, M F; Romanova, L Iu; Kozlovskaya, L I; Maikova, G B; Kholodilov, I S; Karganova, G G

    2016-04-29

    Tick-borne encephalitis (TBE) circulates widely in the territory of Eurasia with up to 10,000 cases registered annually. The TBE virus (TBEV) includes three main subtypes: European, Siberian and Far-Eastern, and two new Asiatic variants, phylogenetically distant from the others. The inactivated antigen of European or Far-Eastern strains is used in commercial TBE vaccines. A set of 14 TBEV strains, isolated in 1937-2008, with different passage histories, representing all subtypes and variants, was used in this work. The chosen set covers almost all the TBE area. Sera of mice, immunized with the TBE vaccine Moscow, prepared from the TBEV strain Sofjin, were studied in a plaque neutralization test against the set of TBEV strains. The vaccine induced antibodies at a protective titer against all TBEV strains and Omsk hemorrhagic fever virus (OHFV) with Е protein amino acid distances of 0.008-0.069, but not against Powassan virus. We showed that after a course of two immunizations, factors such as the period between vaccinations (1-4 weeks), the challenging virus dose (30-1000 LD50) and terms of challenge (1-4 weeks after the last immunization) did not significantly affect the assessment of protective efficacy of the vaccine in vivo. The protective effect of the TBE vaccine Moscow against the set of TBEV strains and the OHFV was demonstrated in in vivo experiments. TBE vaccine Moscow did not protect mice against 10 LD50 of the Powassan virus. We showed that this range of Е protein amino acid distances between the vaccine strain and challenging virus do not have a decisive impact on the TBE vaccine protective effect in vitro and in vivo. Moreover, the TBE vaccine Moscow induces an immune response protective against a wide range of TBEV variants. PMID:27013433

  7. Eliminating Encephalitogenic T Cells without Undermining Protective Immunity

    PubMed Central

    McNally, Jonathan P.; Elfers, Eileen E.; Terrell, Catherine E.; Grunblatt, Eli; Hildeman, David A.

    2014-01-01

    The current clinical approach for treating autoimmune diseases is to broadly blunt immune responses as a means of preventing autoimmune pathology. Among the major side effects of this strategy are depressed beneficial immunity and increased rates of infections and tumors. Using the experimental autoimmune encephalomyelitis model for human multiple sclerosis, we report a novel alternative approach for purging autoreactive T cells that spares beneficial immunity. The moderate and temporally limited use of etoposide, a topoisomerase inhibitor, to eliminate encephalitogenic T cells significantly reduces the onset and severity of experimental autoimmune encephalomyelitis, dampens cytokine production and overall pathology, while dramatically limiting the off-target effects on naive and memory adaptive immunity. Etoposide-treated mice show no or significantly ameliorated pathology with reduced antigenic spread, yet have normal T cell and T-dependent B cell responses to de novo antigenic challenges as well as unimpaired memory T cell responses to viral rechallenge. Thus, etoposide therapy can selectively ablate effector T cells and limit pathology in an animal model of autoimmunity while sparing protective immune responses. This strategy could lead to novel approaches for the treatment of autoimmune diseases with both enhanced efficacy and decreased treatment-associated morbidities. PMID:24277699

  8. Role of basophils in protective immunity to parasitic infections.

    PubMed

    Eberle, Joerg U; Voehringer, David

    2016-09-01

    Basophils have been recognized as important players for protective immunity against a variety of different endo- and ectoparasites. Although basophils represent a relatively rare and short-lived cell type, they produce large quantities of effector molecules including histamine, cytokines, chemokines, and lipid mediators which promote type 2 immune responses. Basophils can be activated either directly by parasite-derived factors or indirectly by recognition of parasite-derived antigens via IgE bound to its high-affinity receptor FcεRI on the cell surface. Many parasitic infections cause expansion and tissue recruitment of basophils, but the role of basophils for protective immunity remains poorly understood. The development of basophil-deficient mouse models over the past few years makes it possible to study their contributions in various infections. We review here the current knowledge regarding the role of basophils for protective or immunomodulatory functions of basophils mainly during infections of mice with protozoan parasites, helminths, and ectoparasites. PMID:27116557

  9. Protective immunity following vaccination: how is it defined?

    PubMed

    Amanna, Ian J; Messaoudi, Ilhem; Slifka, Mark K

    2008-01-01

    Vaccination represents an important medical breakthrough pioneered by Edward Jenner over 200 years ago when he developed the world's first vaccine against smallpox. To this day, vaccination remains the most effective means available for combating infectious disease. There are currently over 20 vaccines licensed for use within the US with many more vaccines in the R&D pipeline. Although vaccines must demonstrate clinical efficacy in order to receive FDA approval, the correlates of immunity vary remarkably between different vaccines and may be based primarily on animal studies, clinical evidence, or a combination of these sources of information. Correlates of protection are critical for measuring vaccine efficacy but researchers should know the history and limitations of these values. As vaccine technologies advance, the way in which we measure and define protective correlates may need to evolve as well. Here, we describe the correlates of protective immunity for vaccines against smallpox, tetanus, yellow fever and measles and compare these to a more recently introduced vaccine against varicella zoster virus, wherein a strict correlate of immunity has yet to be fully defined. PMID:18398296

  10. Taenia crassiceps cysticercosis: humoral immune response and protection elicited by DNA immunization.

    PubMed

    Rosas, G; Cruz-Revilla, C; Fragoso, G; López-Casillas, F; Pérez, A; Bonilla, M A; Rosales, R; Sciutto, E

    1998-06-01

    The purpose of this study was to evaluate DNA vaccination in cysticercosis prevention by using a Taenia crassiceps cDNA of a recombinant antigen (KETc7) that has been reported as protective against murine cysticercosis. The KETc7 cDNA was cloned into the pcDNA3 plasmid alone or with the betaglycan signal peptide sequence (pTc-7 and pTc-sp7, respectively). Positive expression of the pTc-sp7 product was confirmed by transfection of C33 cells and immunofluorescence using sera of mice infected with T. crassiceps. Immunization of mice with 3 injections of pTc-sp7 DNA at the higher dose (200 microg) was the most effective to induce antibody with or without bupivacaine. Immunization with pTc-sp7 induced protection against challenge with T. crassiceps cysticerci as successfully as previously observed with the KETc7 recombinant protein. Antibodies elicited by DNA immunization with pTc-sp7 specifically reacted with the native protein of 56 kDa previously reported, which is immunolocalized in the tegument of T. crassiceps cysticerci. The 56-kDa antigen is also present in Taenia solium oncospheres, cysticerci, and adult tissue. The protection induced in DNA-immunized mice and the observation that the injected plasmid remains as an episomic form within muscle cells, encouraged us to continue testing this procedure to prevent T. solium cysticercosis.

  11. Human immune system mice immunized with Plasmodium falciparum circumsporozoite protein induce protective human humoral immunity against malaria.

    PubMed

    Huang, Jing; Li, Xiangming; Coelho-dos-Reis, Jordana G A; Zhang, Min; Mitchell, Robert; Nogueira, Raquel Tayar; Tsao, Tiffany; Noe, Amy R; Ayala, Ramses; Sahi, Vincent; Gutierrez, Gabriel M; Nussenzweig, Victor; Wilson, James M; Nardin, Elizabeth H; Nussenzweig, Ruth S; Tsuji, Moriya

    2015-12-01

    In this study, we developed human immune system (HIS) mice that possess functional human CD4+ T cells and B cells, named HIS-CD4/B mice. HIS-CD4/B mice were generated by first introducing HLA class II genes, including DR1 and DR4, along with genes encoding various human cytokines and human B cell activation factor (BAFF) to NSG mice by adeno-associated virus serotype 9 (AAV9) vectors, followed by engrafting human hematopoietic stem cells (HSCs). HIS-CD4/B mice, in which the reconstitution of human CD4+ T and B cells resembles to that of humans, produced a significant level of human IgG against Plasmodium falciparum circumsporozoite (PfCS) protein upon immunization. CD4+ T cells in HIS-CD4/B mice, which possess central and effector memory phenotypes like those in humans, are functional, since PfCS protein-specific human CD4+ T cells secreting IFN-γ and IL-2 were detected in immunized HIS-CD4/B mice. Lastly, PfCS protein-immunized HIS-CD4/B mice were protected from in vivo challenge with transgenic P. berghei sporozoites expressing the PfCS protein. The immune sera collected from protected HIS-CD4/B mice reacted against transgenic P. berghei sporozoites expressing the PfCS protein and also inhibited the parasite invasion into hepatocytes in vitro. Taken together, these studies show that our HIS-CD4/B mice could mount protective human anti-malaria immunity, consisting of human IgG and human CD4+ T cell responses both specific for a human malaria antigen.

  12. Human immune system mice immunized with Plasmodium falciparum circumsporozoite protein induce protective human humoral immunity against malaria.

    PubMed

    Huang, Jing; Li, Xiangming; Coelho-dos-Reis, Jordana G A; Zhang, Min; Mitchell, Robert; Nogueira, Raquel Tayar; Tsao, Tiffany; Noe, Amy R; Ayala, Ramses; Sahi, Vincent; Gutierrez, Gabriel M; Nussenzweig, Victor; Wilson, James M; Nardin, Elizabeth H; Nussenzweig, Ruth S; Tsuji, Moriya

    2015-12-01

    In this study, we developed human immune system (HIS) mice that possess functional human CD4+ T cells and B cells, named HIS-CD4/B mice. HIS-CD4/B mice were generated by first introducing HLA class II genes, including DR1 and DR4, along with genes encoding various human cytokines and human B cell activation factor (BAFF) to NSG mice by adeno-associated virus serotype 9 (AAV9) vectors, followed by engrafting human hematopoietic stem cells (HSCs). HIS-CD4/B mice, in which the reconstitution of human CD4+ T and B cells resembles to that of humans, produced a significant level of human IgG against Plasmodium falciparum circumsporozoite (PfCS) protein upon immunization. CD4+ T cells in HIS-CD4/B mice, which possess central and effector memory phenotypes like those in humans, are functional, since PfCS protein-specific human CD4+ T cells secreting IFN-γ and IL-2 were detected in immunized HIS-CD4/B mice. Lastly, PfCS protein-immunized HIS-CD4/B mice were protected from in vivo challenge with transgenic P. berghei sporozoites expressing the PfCS protein. The immune sera collected from protected HIS-CD4/B mice reacted against transgenic P. berghei sporozoites expressing the PfCS protein and also inhibited the parasite invasion into hepatocytes in vitro. Taken together, these studies show that our HIS-CD4/B mice could mount protective human anti-malaria immunity, consisting of human IgG and human CD4+ T cell responses both specific for a human malaria antigen. PMID:26410104

  13. Acquired immune response of white leghorn hens to populations of northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago).

    PubMed

    DeVaney, J A; Ziprin, R L

    1980-08-01

    Three levels (high, low and control) of northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), were maintained on White Leghorn hens for 24 weeks. The hens were then treated with carbaryl to eradicate the mites, were induced to molt, and were reinfested with mites 9 weeks later. Subsequent levels of mites on the three groups showed that the degree of acquired immunity was related to the initial level of mite infestation. PMID:7413581

  14. Partially Protective Immunity Induced by a 20 kDa Protein Secreted by Trichinella spiralis Stichocytes

    PubMed Central

    Wang, Lei; Gu, Yuan; Zhan, Bin; Zhu, Xinping

    2015-01-01

    Background Trichinella spiralis infection induces protective immunity against re-infection in animal models. Identification of the antigens eliciting acquired immunity during infection is important for vaccine development against Trichinella infection and immunodiagnosis. Methods and Findings The T. spiralis adult cDNA library was immunoscreened with sera from pigs experimentally infected with 20,000 infective T. spiralis larvae. Total 43 positive clones encoding for 28 proteins were identified; one of the immunodominant proteins was 20 kDa Ts-ES-1 secreted by Trichinella stichocytes and existing in the excretory/secretory (ES) products of T. spiralis adult and muscle larval worms. Ts-ES-1 contains 172 amino acids with a typical signal peptide in the first 20 amino acids. The expression of Ts-ES-1 was detected in both the adult and muscle larval stages at the mRNA and protein expression levels. Mice immunized with recombinant Ts-ES-1 (rTs-ES-1) formulated with ISA50v2 adjuvant exhibited a significant worm reduction in both the adult worm (27%) and muscle larvae burden (42.1%) after a challenge with T. spiralis compared to the adjuvant control group (p<0.01). The rTs-ES-1-induced protection was associated with a high level of specific anti-Ts-ES-1 IgG antibodies and a Th1/Th2 mixed immune response. Conclusion The newly identified rTs-ES-1 is an immunodominant protein secreted by Trichinella stichocytes during natural infection and enables to the induction of partial protective immunity in vaccinated mice against Trichinella infection. Therefore, rTs-ES-1 is a potential candidate for vaccine development against trichinellosis. PMID:26288365

  15. Generation of protective immune response against anthrax by oral immunization with protective antigen plant-based vaccine.

    PubMed

    Gorantala, Jyotsna; Grover, Sonam; Rahi, Amit; Chaudhary, Prerna; Rajwanshi, Ravi; Sarin, Neera Bhalla; Bhatnagar, Rakesh

    2014-04-20

    In concern with frequent recurrence of anthrax in endemic areas and inadvertent use of its spores as biological weapon, the development of an effective anthrax vaccine suitable for both human and veterinary needs is highly desirable. A simple oral delivery through expression in plant system could offer promising alternative to the current methods that rely on injectable vaccines extracted from bacterial sources. In the present study, we have expressed protective antigen (PA) gene in Indian mustard by Agrobacterium-mediated transformation and in tobacco by plastid transformation. Putative transgenic lines were verified for the presence of transgene and its expression by molecular analysis. PA expressed in transgenic lines was biologically active as evidenced by macrophage lysis assay. Intraperitoneal (i.p.) and oral immunization with plant PA in murine model indicated high serum PA specific IgG and IgA antibody titers. PA specific mucosal immune response was noted in orally immunized groups. Further, antibodies indicated lethal toxin neutralizing potential in-vitro and conferred protection against in-vivo toxin challenge. Oral immunization experiments demonstrated generation of immunoprotective response in mice. Thus, our study examines the feasibility of oral PA vaccine expressed in an edible plant system against anthrax.

  16. I kappa B kinase alpha (IKKα) activity is required for functional maturation of dendritic cells and acquired immunity to infection.

    PubMed

    Mancino, Alessandra; Habbeddine, Mohamed; Johnson, Ella; Luron, Lionel; Bebien, Magali; Memet, Sylvie; Fong, Carol; Bajenoff, Marc; Wu, Xuefeng; Karin, Michael; Caamano, Jorge; Chi, Hongbo; Seed, Michael; Lawrence, Toby

    2013-03-20

    Dendritic cells (DC) are required for priming antigen-specific T cells and acquired immunity to many important human pathogens, including Mycobacteriuim tuberculosis (TB) and influenza. However, inappropriate priming of auto-reactive T cells is linked with autoimmune disease. Understanding the molecular mechanisms that regulate the priming and activation of naïve T cells is critical for development of new improved vaccines and understanding the pathogenesis of autoimmune diseases. The serine/threonine kinase IKKα (CHUK) has previously been shown to have anti-inflammatory activity and inhibit innate immunity. Here, we show that IKKα is required in DC for priming antigen-specific T cells and acquired immunity to the human pathogen Listeria monocytogenes. We describe a new role for IKKα in regulation of IRF3 activity and the functional maturation of DC. This presents a unique role for IKKα in dampening inflammation while simultaneously promoting adaptive immunity that could have important implications for the development of new vaccine adjuvants and treatment of autoimmune diseases.

  17. Gut epithelial barrier dysfunction in human immunodeficiency virus-hepatitis C virus coinfected patients: Influence on innate and acquired immunity

    PubMed Central

    Márquez, Mercedes; Fernández Gutiérrez del Álamo, Clotilde; Girón-González, José Antonio

    2016-01-01

    Even in cases where viral replication has been controlled by antiretroviral therapy for long periods of time, human immunodeficiency virus (HIV)-infected patients have several non-acquired immunodeficiency syndrome (AIDS) related co-morbidities, including liver disease, cardiovascular disease and neurocognitive decline, which have a clear impact on survival. It has been considered that persistent innate and acquired immune activation contributes to the pathogenesis of these non-AIDS related diseases. Immune activation has been related with several conditions, remarkably with the bacterial translocation related with the intestinal barrier damage by the HIV or by hepatitis C virus (HCV)-related liver cirrhosis. Consequently, increased morbidity and mortality must be expected in HIV-HCV coinfected patients. Disrupted gut barrier lead to an increased passage of microbial products and to an activation of the mucosal immune system and secretion of inflammatory mediators, which in turn might increase barrier dysfunction. In the present review, the intestinal barrier structure, measures of intestinal barrier dysfunction and the modifications of them in HIV monoinfection and in HIV-HCV coinfection will be considered. Both pathogenesis and the consequences for the progression of liver disease secondary to gut microbial fragment leakage and immune activation will be assessed. PMID:26819512

  18. Testing the "toxin hypothesis of allergy": Mast cells, IgE, and innate and acquired immune responses to venoms*

    PubMed Central

    Tsai, Mindy; Starkl, Philipp; Marichal, Thomas; Galli, Stephen J.

    2015-01-01

    Summary Work in mice indicates that innate functions of mast cells, particularly degradation of venom toxins by mast cell-derived proteases, can enhance resistance to certain arthropod or reptile venoms. Recent reports indicate that acquired Th2 immune responses associated with the production of IgE antibodies, induced by Russell’s viper venom or honeybee venom, or by a component of honeybee venom, bee venom phospholipase 2 (bvPLA2), can increase the resistance of mice to challenge with potentially lethal doses of either of the venoms or bvPLA2. These findings support the conclusion that, in contrast to the detrimental effects associated with allergic Th2 immune responses, mast cells and IgE-dependent immune responses to venoms can contribute to innate and adaptive resistance to venom-induced pathology and mortality. PMID:26210895

  19. Influenza vaccination in the face of immune exhaustion: is herd immunity effective for protecting the elderly?

    PubMed

    Lang, Pierre Olivier; Samaras, Dimitrios; Samaras, Nikolaos; Govind, Sheila; Aspinall, Richard

    2011-01-01

    At the start of the 21st century, seasonal influenza virus infection is still a major public health concern across the world. The recent body of evidence confirms that trivalent inactivated influenza vaccines (TIVs) are not optimal within the population who account for approximately 90% of all influenza-related death: elderly and chronically ill individuals regardless of age. With the ever increasing aging of the world population and the recent fears of any pandemic influenza rife, great efforts and resources have been dedicated to developing more immunogenic vaccines and strategies for enhancing protection in these higher-risk groups. This paper describes the mechanisms that shape immune response at the extreme ages of life and how they have been taken into account to design more effective immunization strategies for these vulnerable populations. Furthermore, consideration will be given to how herd immunity may provide an effective strategy in preventing the burden of seasonal influenza infection within the aged population.

  20. Influenza Vaccination in the Face of Immune Exhaustion: Is Herd Immunity Effective for Protecting the Elderly?

    PubMed Central

    Lang, Pierre Olivier; Samaras, Dimitrios; Samaras, Nikolaos; Govind, Sheila; Aspinall, Richard

    2011-01-01

    At the start of the 21st century, seasonal influenza virus infection is still a major public health concern across the world. The recent body of evidence confirms that trivalent inactivated influenza vaccines (TIVs) are not optimal within the population who account for approximately 90% of all influenza-related death: elderly and chronically ill individuals regardless of age. With the ever increasing aging of the world population and the recent fears of any pandemic influenza rife, great efforts and resources have been dedicated to developing more immunogenic vaccines and strategies for enhancing protection in these higher-risk groups. This paper describes the mechanisms that shape immune response at the extreme ages of life and how they have been taken into account to design more effective immunization strategies for these vulnerable populations. Furthermore, consideration will be given to how herd immunity may provide an effective strategy in preventing the burden of seasonal influenza infection within the aged population. PMID:23074656

  1. Biomimetic Antigenic Nanoparticles Elicit Controlled Protective Immune Response to Influenza

    PubMed Central

    Patterson, Dustin P.; Rynda-Apple, Agnieszka; Harmsen, Ann L.; Harmsen, Allen G.; Douglas, Trevor

    2013-01-01

    Here we present a biomimetic strategy towards nanoparticle design for controlled immune response through encapsulation of conserved internal influenza proteins on the interior of virus like particles (VLPs) to direct CD8+ cytotoxic T cell protection. Programmed encapsulation and sequestration of the conserved nucleoprotein (NP) from influenza on the interior of a VLP, derived from the bacteriophage P22, results in a vaccine that provides multi-strain protection against 100 times lethal doses of influenza in an NP specific CD8+ T cell-dependent manner. VLP assembly and encapsulation of the immunogenic NP cargo protein is the result of a genetically programmed self-assembly making this strategy amendable to the quick production of vaccines to rapidly emerging pathogens. Addition of adjuvants or targeting molecules were not required for eliciting the protective response. PMID:23540530

  2. Protective antigens against glanders identified by expression library immunization.

    PubMed

    Whitlock, Gregory C; Robida, Mark D; Judy, Barbara M; Qazi, Omar; Brown, Katherine A; Deeraksa, Arpaporn; Taylor, Katherine; Massey, Shane; Loskutov, Andrey; Borovkov, Alex Y; Brown, Kevin; Cano, Jose A; Torres, Alfredo G; Estes, D Mark; Sykes, Kathryn F

    2011-01-01

    Burkholderia are highly evolved Gram-negative bacteria that primarily infect solipeds but are transmitted to humans by ingestion and cutaneous or aerosol exposures. Heightened concern over human infections of Burkholderia mallei and the very closely related species B. pseudomallei is due to the pathogens' proven effectiveness as bioweapons, and to the increased potential for natural opportunistic infections in the growing diabetic and immuno-compromised populations. These Burkholderia species are nearly impervious to antibiotic treatments and no vaccine exists. In this study, the genome of the highly virulent B. mallei ATCC23344 strain was examined by expression library immunization for gene-encoded protective antigens. This protocol for genomic-scale functional screening was customized to accommodate the unusually large complexity of Burkholderia, and yielded 12 new putative vaccine candidates. Five of the candidates were individually tested as protein immunogens and three were found to confer significant partial protection against a lethal pulmonary infection in a murine model of disease. Determinations of peripheral blood cytokine and chemokine profiles following individual protein immunizations show that interleukin-2 (IL-2) and IL-4 are elicited by the three confirmed candidates, but unexpectedly interferon-γ and tumor necrosis factor-α are not. We suggest that these pathogen components, discovered using genetic immunization and confirmed in a conventional protein format, will be useful toward the development of a safe and effective glanders vaccine.

  3. Protective Antigens Against Glanders Identified by Expression Library Immunization

    PubMed Central

    Whitlock, Gregory C.; Robida, Mark D.; Judy, Barbara M.; Qazi, Omar; Brown, Katherine A.; Deeraksa, Arpaporn; Taylor, Katherine; Massey, Shane; Loskutov, Andrey; Borovkov, Alex Y.; Brown, Kevin; Cano, Jose A.; Magee, D. Mitchell; Torres, Alfredo G.; Estes, D. Mark; Sykes, Kathryn F.

    2011-01-01

    Burkholderia are highly evolved Gram-negative bacteria that primarily infect solipeds but are transmitted to humans by ingestion and cutaneous or aerosol exposures. Heightened concern over human infections of Burkholderia mallei and the very closely related species B. pseudomallei is due to the pathogens’ proven effectiveness as bioweapons, and to the increased potential for natural opportunistic infections in the growing diabetic and immuno-compromised populations. These Burkholderia species are nearly impervious to antibiotic treatments and no vaccine exists. In this study, the genome of the highly virulent B. mallei ATCC23344 strain was examined by expression library immunization for gene-encoded protective antigens. This protocol for genomic-scale functional screening was customized to accommodate the unusually large complexity of Burkholderia, and yielded 12 new putative vaccine candidates. Five of the candidates were individually tested as protein immunogens and three were found to confer significant partial protection against a lethal pulmonary infection in a murine model of disease. Determinations of peripheral blood cytokine and chemokine profiles following individual protein immunizations show that interleukin-2 (IL-2) and IL-4 are elicited by the three confirmed candidates, but unexpectedly interferon-γ and tumor necrosis factor-α are not. We suggest that these pathogen components, discovered using genetic immunization and confirmed in a conventional protein format, will be useful toward the development of a safe and effective glanders vaccine. PMID:22125550

  4. Comparison of Protective Immune Responses to Apicomplexan Parasites

    PubMed Central

    Frölich, Sonja; Entzeroth, Rolf; Wallach, Michael

    2012-01-01

    Members of the phylum Apicomplexa, which includes the species Plasmodium, Eimeria, Toxoplasma, and Babesia amongst others, are the most successful intracellular pathogens known to humankind. The widespread acquisition of antimicrobial resistance to most drugs used to date has sparked a great deal of research and commercial interest in the development of vaccines as alternative control strategies. A few antigens from the asexual and sexual stages of apicomplexan development have been identified and their genes characterised; however, the fine cellular and molecular details of the effector mechanisms crucial for parasite inhibition and stimulation of protective immunity are still not entirely understood. This paper provides an overview of what is currently known about the protective immune response against the various types of apicomplexan parasites and focuses mainly on the similarities of these pathogens and their host interaction. Finally, the evolutionary relationships of these parasites and their hosts, as well as the modulation of immune functions that are critical in determining the outcome of the infection by these pathogenic organisms, are discussed. PMID:21876783

  5. Soluble TNFRp75 regulates host protective immunity against Mycobacterium tuberculosis

    PubMed Central

    Keeton, Roanne; Allie, Nasiema; Dambuza, Ivy; Abel, Brian; Hsu, Nai-Jen; Sebesho, Boipelo; Randall, Philippa; Burger, Patricia; Fick, Elizabeth; Quesniaux, Valerie F.J.; Ryffel, Bernhard; Jacobs, Muazzam

    2014-01-01

    Development of host protective immunity against Mycobacterium tuberculosis infection is critically dependent on the inflammatory cytokine TNF. TNF signals through 2 receptors, TNFRp55 and TNFRp75; however, the role of TNFRp75-dependent signaling in immune regulation is poorly defined. Here we found that mice lacking TNFRp75 exhibit greater control of M. tuberculosis infection compared with WT mice. TNFRp75–/– mice developed effective bactericidal granulomas and demonstrated increased pulmonary recruitment of activated DCs. Moreover, IL-12p40–dependent migration of DCs to lung draining LNs of infected TNFRp75–/– mice was substantially higher than that observed in WT M. tuberculosis–infected animals and was associated with enhanced frequencies of activated M. tuberculosis–specific IFN-γ–expressing CD4+ T cells. In WT mice, TNFRp75 shedding correlated with markedly reduced bioactive TNF levels and IL-12p40 expression. Neutralization of TNFRp75 in M. tuberculosis–infected WT BM-derived DCs (BMDCs) increased production of bioactive TNF and IL-12p40 to a level equivalent to that produced by TNFRp75–/– BMDCs. Addition of exogenous TNFRp75 to TNFRp75–/– BMDCs infected with M. tuberculosis decreased IL-12p40 synthesis, demonstrating that TNFRp75 shedding regulates DC activation. These data indicate that TNFRp75 shedding downmodulates protective immune function and reduces host resistance and survival; therefore, targeting TNFRp75 may be beneficial for improving disease outcome. PMID:24569452

  6. Salmonella abortusovis infection in susceptible BALB/cby mice: importance of Lyt-2+ and L3T4+ T cells in acquired immunity and granuloma formation.

    PubMed

    Guilloteau, L; Buzoni-Gatel, D; Bernard, F; Lantier, I; Lantier, F

    1993-01-01

    The role of T cells in granulomatous responses and in acquired immunity against Salmonella abortusovis (SAO) infection was studied in a murine model. Mice were subcutaneously (s.c.) vaccinated with a live attenuated strain of SAO. One month after vaccination, the transfer of primed spleen cells (1 x 10(8) cells per mouse) to syngeneic recipient mice conferred a significant protection of 3 log10, measured by spleen colonization on day 6 after s.c. challenge. In vitro treatment of spleen cells, before the transfer, with anti-Lyt-2 monoclonal antibody (IgG2b isotype MAb) and complement significantly impaired the protective activity. Treatment with anti-L3T4 MAb also diminished transferred protection, but to a lesser degree. Depletion of both L3T4+ and Lyt-2+ T cells completely abrogated protection. MAb treatment of spleen cells in vitro did not seem to have any effect on antibody response in recipient mice. Six days after the challenge protected recipient mice showed organized granulomas in the liver containing Mac-1+ macrophages and L3T4+ T cells. In non-protected mice at 6 days post-challenge, large infiltrates of T lymphocytes and macrophages were observed, but as numerous lesions with necrosis of hepatocytes; no granuloma were seen. In our experimental conditions, Lyt-2+ and L3T4+ T cells appeared to play, alone and in synergy, a role in vaccine-induced immunity against SAO and hepatic granulomas may contribute to the control of the infection.

  7. Protective immunity and safety of a genetically modified influenza virus vaccine.

    PubMed

    Barbosa, Rafael Polidoro Alves; Salgado, Ana Paula Carneiro; Garcia, Cristiana Couto; Filho, Bruno Galvão; Gonçalves, Ana Paula de Faria; Lima, Braulio Henrique Freire; Lopes, Gabriel Augusto Oliveira; Rachid, Milene Alvarenga; Peixoto, Andiara Cristina Cardoso; de Oliveira, Danilo Bretas; Ataíde, Marco Antônio; Zirke, Carla Aparecida; Cotrim, Tatiane Marques; Costa, Érica Azevedo; Almeida, Gabriel Magno de Freitas; Russo, Remo Castro; Gazzinelli, Ricardo Tostes; Machado, Alexandre de Magalhães Vieira

    2014-01-01

    Recombinant influenza viruses are promising viral platforms to be used as antigen delivery vectors. To this aim, one of the most promising approaches consists of generating recombinant viruses harboring partially truncated neuraminidase (NA) segments. To date, all studies have pointed to safety and usefulness of this viral platform. However, some aspects of the inflammatory and immune responses triggered by those recombinant viruses and their safety to immunocompromised hosts remained to be elucidated. In the present study, we generated a recombinant influenza virus harboring a truncated NA segment (vNA-Δ) and evaluated the innate and inflammatory responses and the safety of this recombinant virus in wild type or knock-out (KO) mice with impaired innate (Myd88 -/-) or acquired (RAG -/-) immune responses. Infection using truncated neuraminidase influenza virus was harmless regarding lung and systemic inflammatory response in wild type mice and was highly attenuated in KO mice. We also demonstrated that vNA-Δ infection does not induce unbalanced cytokine production that strongly contributes to lung damage in infected mice. In addition, the recombinant influenza virus was able to trigger both local and systemic virus-specific humoral and CD8+ T cellular immune responses which protected immunized mice against the challenge with a lethal dose of homologous A/PR8/34 influenza virus. Taken together, our findings suggest and reinforce the safety of using NA deleted influenza viruses as antigen delivery vectors against human or veterinary pathogens. PMID:24927156

  8. Immune response

    MedlinePlus

    Innate immunity; Humoral immunity; Cellular immunity; Immunity; Inflammatory response; Acquired (adaptive) immunity ... and usually does not react against them. INNATE IMMUNITY Innate, or nonspecific, immunity is the defense system ...

  9. Cutaneous leishmaniasis: immune responses in protection and pathogenesis.

    PubMed

    Scott, Phillip; Novais, Fernanda O

    2016-09-01

    Cutaneous leishmaniasis is a major public health problem and causes a range of diseases from self-healing infections to chronic disfiguring disease. Currently, there is no vaccine for leishmaniasis, and drug therapy is often ineffective. Since the discovery of CD4(+) T helper 1 (TH1) cells and TH2 cells 30 years ago, studies of cutaneous leishmaniasis in mice have answered basic immunological questions concerning the development and maintenance of CD4(+) T cell subsets. However, new strategies for controlling the human disease have not been forthcoming. Nevertheless, advances in our knowledge of the cells that participate in protection against Leishmania infection and the cells that mediate increased pathology have highlighted new approaches for vaccine development and immunotherapy. In this Review, we discuss the early events associated with infection, the CD4(+) T cells that mediate protective immunity and the pathological role that CD8(+) T cells can have in cutaneous leishmaniasis. PMID:27424773

  10. Immunization with extracellular proteins of Mycobacterium tuberculosis induces cell-mediated immune responses and substantial protective immunity in a guinea pig model of pulmonary tuberculosis.

    PubMed Central

    Pal, P G; Horwitz, M A

    1992-01-01

    We have studied the capacity of a selected fraction of Mycobacterium tuberculosis extracellular proteins (EP) released into broth culture by mid-logarithmic-growth-phase organisms to induce cell-mediated immune responses and protective immunity in a guinea pig model of pulmonary tuberculosis. Guinea pigs infected with M. tuberculosis by aerosol but not uninfected control guinea pigs exhibit strong cell-mediated immune responses to EP, manifest by dose-dependent cutaneous delayed-type hypersensitivity and splenic lymphocyte proliferation. Guinea pigs immunized subcutaneously with EP but not sham-immunized control guinea pigs also develop strong cell-mediated immune responses to EP, manifest by dose-dependent cutaneous delayed-type hypersensitivity and splenic lymphocyte proliferation. EP is nonlethal and nontoxic to guinea pigs upon subcutaneous immunization. Guinea pigs immunized with EP and then challenged with aerosolized M. tuberculosis exhibit protective immunity. In five independent experiments, EP-immunized guinea pigs were consistently protected against clinical illness, including weight loss. Compared with EP-immunized guinea pigs, sham-immunized control guinea pigs lost 12.9 +/- 2.0% (mean +/- SE) of their total weight. EP-immunized guinea pigs also had a 10-fold reduction in viable M. tuberculosis bacilli in their lungs and spleens (P = 0.004 and 0.001, respectively) compared with sham-immunized control animals. In the two experiments in which some guinea pigs died after aerosol challenge, EP-immunized animals were protected from death. Whereas all 12 (100%) EP-immunized guinea pigs survived challenge with aerosolized M. tuberculosis, only 6 of 12 (50%) sham-immunized control guinea pigs survived challenge (P = 0.007, Fisher exact test). This study demonstrates that actively growing M. tuberculosis cells release immunoprotective molecules extracellularly, that a subunit vaccine against tuberculosis is feasible, and that extracellular molecules of M

  11. Acidic chitinase primes the protective immune response to gastrointestinal nematodes.

    PubMed

    Vannella, Kevin M; Ramalingam, Thirumalai R; Hart, Kevin M; de Queiroz Prado, Rafael; Sciurba, Joshua; Barron, Luke; Borthwick, Lee A; Smith, Allen D; Mentink-Kane, Margaret; White, Sandra; Thompson, Robert W; Cheever, Allen W; Bock, Kevin; Moore, Ian; Fitz, Lori J; Urban, Joseph F; Wynn, Thomas A

    2016-05-01

    Acidic mammalian chitinase (AMCase) is known to be induced by allergens and helminths, yet its role in immunity is unclear. Using AMCase-deficient mice, we show that AMCase deficiency reduced the number of group 2 innate lymphoid cells during allergen challenge but was not required for establishment of type 2 inflammation in the lung in response to allergens or helminths. In contrast, AMCase-deficient mice showed a profound defect in type 2 immunity following infection with the chitin-containing gastrointestinal nematodes Nippostrongylus brasiliensis and Heligmosomoides polygyrus bakeri. The impaired immunity was associated with reduced mucus production and decreased intestinal expression of the signature type 2 response genes Il13, Chil3, Retnlb, and Clca1. CD103(+) dendritic cells, which regulate T cell homing, were also reduced in mesenteric lymph nodes of infected AMCase-deficient mice. Thus, AMCase functions as a critical initiator of protective type 2 responses to intestinal nematodes but is largely dispensable for allergic responses in the lung. PMID:27043413

  12. Suppression of Hyperactive Immune Responses Protects against Nitrogen Mustard Injury

    PubMed Central

    Au, Liemin; Meisch, Jeffrey P; Das, Lopa M; Binko, Amy M; Boxer, Rebecca S; Wen, Amy M; Steinmetz, Nicole F; Lu, Kurt Q

    2015-01-01

    DNA alkylating agents like nitrogen mustard (NM) are easily absorbed through the skin and exposure to such agents manifest not only in direct cellular death but also in triggering inflammation. We show that toxicity resulting from topical mustard exposure is mediated in part by initiating exaggerated host innate immune responses. Using an experimental model of skin exposure to NM we observe activation of inflammatory dermal macrophages that exacerbate local tissue damage in an inducible nitric oxide synthase (iNOS)-dependent manner. Subsequently these activated dermal macrophages reappear in the bone marrow to aid in disruption of hematopoiesis and contribute ultimately to mortality in an experimental mouse model of topical NM exposure. Intervention with a single dose of 25-hydroxyvitamin D3 (25(OH)D) is capable of suppressing macrophage-mediated iNOS production resulting in mitigation of local skin destruction, enhanced tissue repair, protection from marrow depletion, and rescue from severe precipitous wasting. These protective effects are recapitulated experimentally using pharmacological inhibitors of iNOS or by compounds that locally deplete skin macrophages. Taken together, these data highlight a critical unappreciated role of the host innate immune system in exacerbating injury following exposure to NM and support the translation of 25(OH)D in the therapeutic use against these chemical agents. PMID:26288355

  13. Plasmodesmata localizing proteins regulate transport and signaling during systemic acquired immunity in plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Systemic acquired resistance (SAR) in plants is mediated by the signaling molecules azelaic acid (AzA),glycerol-3-phosphate (G3P), and salicylic acid (SA).Here, we show that AzA and G3P transport occurs via the symplastic route, which is regulated by channels known as plasmodesmata (PD). In contrast...

  14. Malaria Transmission and Naturally Acquired Immunity to PfEMP-1

    PubMed Central

    Piper, Karen P.; Hayward, Rhian E.; Cox, Martin J.; Day, Karen P.

    1999-01-01

    Why there are so few gametocytes (the transmission stage of malaria) in the blood of humans infected with Plasmodium spp. is intriguing. This may be due either to reproductive restraint by the parasite or to unidentified gametocyte-specific immune-mediated clearance mechanisms. We propose another mechanism, a cross-stage immunity to Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP-1). This molecule is expressed on the surface of the erythrocyte infected with either trophozoite or early gametocyte parasites. Immunoglobulin G antibodies to PfEMP-1, expressed on both life cycle stages, were measured in residents from an area where malaria is endemic, Papua New Guinea. Anti-PfEMP-1 prevalence increased with age, mirroring the decline in both the prevalence and the density of asexual and transmission stages in erythrocytes. These data led us to propose that immunity to PfEMP-1 may influence malaria transmission by regulation of the production of gametocytes. This regulation may be achieved in two ways: (i) by controlling asexual proliferation and density and (ii) by affecting gametocyte maturation. PMID:10569752

  15. The Immune Response in Measles: Virus Control, Clearance and Protective Immunity

    PubMed Central

    Griffin, Diane E.

    2016-01-01

    Measles is an acute systemic viral infection with immune system interactions that play essential roles in multiple stages of infection and disease. Measles virus (MeV) infection does not induce type 1 interferons, but leads to production of cytokines and chemokines associated with nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) signaling and activation of the NACHT, LRR and PYD domains-containing protein (NLRP3) inflammasome. This restricted response allows extensive virus replication and spread during a clinically silent latent period of 10–14 days. The first appearance of the disease is a 2–3 day prodrome of fever, runny nose, cough, and conjunctivitis that is followed by a characteristic maculopapular rash that spreads from the face and trunk to the extremities. The rash is a manifestation of the MeV-specific type 1 CD4+ and CD8+ T cell adaptive immune response with lymphocyte infiltration into tissue sites of MeV replication and coincides with clearance of infectious virus. However, clearance of viral RNA from blood and tissues occurs over weeks to months after resolution of the rash and is associated with a period of immunosuppression. However, during viral RNA clearance, MeV-specific antibody also matures in type and avidity and T cell functions evolve from type 1 to type 2 and 17 responses that promote B cell development. Recovery is associated with sustained levels of neutralizing antibody and life-long protective immunity. PMID:27754341

  16. VISTA Regulates the Development of Protective Antitumor Immunity.

    PubMed

    Le Mercier, Isabelle; Chen, Wenna; Lines, Janet L; Day, Maria; Li, Jiannan; Sergent, Petra; Noelle, Randolph J; Wang, Li

    2014-04-01

    V-domain Ig suppressor of T-cell activation (VISTA) is a novel negative checkpoint ligand that is homologous to PD-L1 and suppresses T-cell activation. This study demonstrates the multiple mechanisms whereby VISTA relieves negative regulation by hematopoietic cells and enhances protective antitumor immunity. VISTA is highly expressed on myeloid cells and Foxp3(+)CD4(+) regulatory cells, but not on tumor cells within the tumor microenvironment (TME). VISTA monoclonal antibody (mAb) treatment increased the number of tumor-specific T cells in the periphery and enhanced the infiltration, proliferation, and effector function of tumor-reactive T cells within the TME. VISTA blockade altered the suppressive feature of the TME by decreasing the presence of monocytic myeloid-derived suppressor cells and increasing the presence of activated dendritic cells within the tumor microenvironment. In addition, VISTA blockade impaired the suppressive function and reduced the emergence of tumor-specific Foxp3(+)CD4(+) regulatory T cells. Consequently, VISTA mAb administration as a monotherapy significantly suppressed the growth of both transplantable and inducible melanoma. Initial studies explored a combinatorial regimen using VISTA blockade and a peptide-based cancer vaccine with TLR agonists as adjuvants. VISTA blockade synergized with the vaccine to effectively impair the growth of established tumors. Our study therefore establishes a foundation for designing VISTA-targeted approaches either as a monotherapy or in combination with additional immune-targeted strategies for cancer immunotherapy.

  17. Naturally-Acquired Immune Response against Plasmodium vivax Rhoptry-Associated Membrane Antigen

    PubMed Central

    Changrob, Siriruk; Wang, Bo; Han, Jin-Hee; Lee, Seong-Kyun; Nyunt, Myat Htut; Lim, Chae Seung; Tsuboi, Takafumi; Chootong, Patchanee; Han, Eun-Taek

    2016-01-01

    Rhoptry-associated membrane antigen (RAMA) is an abundant glycophosphatidylinositol (GPI)-anchored protein that is embedded within the lipid bilayer and is implicated in parasite invasion. Antibody responses against rhoptry proteins are produced by individuals living in a malaria-endemic area, suggesting the immunogenicity of Plasmodium vivax RAMA (PvRAMA) for induction of immune responses during P. vivax infection. To determine whether PvRAMA contributes to the acquisition of immunity to malaria and could be a rational candidate for a vaccine, the presence of memory T cells and the stability of the antibody response against PvRAMA were evaluated in P. vivax-exposed individuals. The immunogenicity of PvRAMA for the induction of T cell responses was evaluated by in vitro stimulation of peripheral blood mononuclear cells (PBMCs). High levels of interferon (IFN)-γ and interleukin (IL)-10 cytokines were detected in the culture supernatant of PBMCs, and the CD4+ T cells predominantly produced IL-10 cytokine. The levels of total anti-PvRAMA immunoglobulin G (IgG) antibody were significantly elevated, and these antibodies persisted over the 12 months of the study. Interestingly, IgG1, IgG2 and IgG3 were the major antibody subtypes in the response to PvRAMA. The frequency of IgG3 in specific to PvRAMA antigen maintained over 12 months. These data could explain the immunogenicity of PvRAMA antigen in induction of both cell-mediated and antibody-mediated immunity in natural P. vivax infection, in which IFN-γ helps antibody class switching toward the IgG1, IgG2 and IgG3 isotypes and IL-10 supports PvRAMA-specific antibody production. PMID:26886867

  18. Opportunistic infections in acquired immune deficiency syndrome result from synergistic defects of both the natural and adaptive components of cellular immunity.

    PubMed Central

    Siegal, F P; Lopez, C; Fitzgerald, P A; Shah, K; Baron, P; Leiderman, I Z; Imperato, D; Landesman, S

    1986-01-01

    We evaluated the cellular immunity of 408 clinically stratified subjects at risk for acquired immune deficiency syndrome (AIDS), to define the role of interferon-alpha production deficits in the pathogenesis of opportunistic infections (OI). We followed 115 prospectively for up to 45 mo. Onset of OI was associated with, and predicted by, deficiency both of interferon-alpha generation in vitro, and of circulating Leu-3a+ cells. Interferon-alpha production is an index of the function of certain non-T, non-B, large granular lymphocytes (LGL) that are independent of T cell help. Leu-3a+ cell counts are a marker of T cell function. OI did not usually develop until both of these mutually independent immune functions were simultaneously critically depressed, leading to a synergistic interaction. These data suggest that the AIDS virus affects a subset of LGL, and that cytokine production by these cells is an important component of the host defense against intracellular pathogens that becomes crucial in the presence of severe T cell immunodeficiency. PMID:3088039

  19. A novel elicitor protein from Phytophthora parasitica induces plant basal immunity and systemic acquired resistance.

    PubMed

    Chang, Yi-Hsuan; Yan, Hao-Zhi; Liou, Ruey-Fen

    2015-02-01

    The interaction between Phytophthora pathogens and host plants involves the exchange of complex molecular signals from both sides. Recent studies of Phytophthora have led to the identification of various apoplastic elicitors known to trigger plant immunity. Here, we provide evidence that the protein encoded by OPEL of Phytophthora parasitica is a novel elicitor. Homologues of OPEL were identified only in oomycetes, but not in fungi and other organisms. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) revealed that OPEL is expressed throughout the development of P. parasitica and is especially highly induced after plant infection. Infiltration of OPEL recombinant protein from Escherichia coli into leaves of Nicotiana tabacum (cv. Samsun NN) resulted in cell death, callose deposition, the production of reactive oxygen species and induced expression of pathogen-associated molecular pattern (PAMP)-triggered immunity markers and salicylic acid-responsive defence genes. Moreover, the infiltration conferred systemic resistance against a broad spectrum of pathogens, including Tobacco mosaic virus, the bacteria wilt pathogen Ralstonia solanacearum and P. parasitica. In addition to the signal peptide, OPEL contains three conserved domains: a thaumatin-like domain, a glycine-rich protein domain and a glycosyl hydrolase (GH) domain. Intriguingly, mutation of a putative laminarinase active site motif in the predicted GH domain abolished its elicitor activity, which suggests enzymatic activity of OPEL in triggering the defence response.

  20. Cell mediated immune response after challenge in Omp25 liposome immunized mice contributes to protection against virulent Brucella abortus 544.

    PubMed

    Goel, Divya; Rajendran, Vinoth; Ghosh, Prahlad C; Bhatnagar, Rakesh

    2013-02-01

    Brucellosis is a disease affecting various domestic and wild life species, and is caused by a bacterium Brucella. Keeping in view the serious economic and medical consequences of brucellosis, efforts have been made to prevent the infection through the use of vaccines. Cell-mediated immune responses [CMI] involving interferon gamma and cytotoxic CD4(+) and CD8(+) T cells are required for removal of intracellular Brucella. Omp25 has been reported to be involved in virulence of Brucella melitensis, Brucella abortus and Brucella ovis. In our previous study, we have shown the protective efficacy of recombinant Omp25, when administered intradermally. In this study, the recombinant Omp25 was formulated in PC-PE liposomes and PLGA microparticles, to enhance the protective immunity generated by it. Significant protection was seen with prime and booster liposome immunization in Balb/c mice against virulent B. abortus 544 as it was comparable to B. abortus S-19 vaccine strain. However, microparticle prime and booster immunization failed to give better protection when compared to B. abortus S-19 vaccine strain. This difference can be attributed to the stimulation of cell mediated immune response in PC-PE liposome immunized mice even after challenge which converted to cytotoxicity seen in CD4(+) and CD8(+) enriched lymphocytes. However, in PLGA microparticle immunized mice, cell mediated immunity was not generated after challenge as observed by decreased cytotoxicity of CD4(+) and CD8(+) enriched lymphocytes. Our study emphasizes on the importance of liposome encapsulating Omp25 immunization in conferring protection against B. abortus 544 challenge in Balb/c mice with a single dose immunization regimen.

  1. Toenail onychomycosis in patients with acquired immune deficiency syndrome: treatment with terbinafine.

    PubMed

    Herranz, P; García, J; De Lucas, R; González, J; Peña, J M; Díaz, R; Casado, M

    1997-10-01

    Skin infections caused by dermatophytes are one of the most frequent dermatological complications in patients with acquired immunodeficiency syndrome (AIDS) resulting from infection with human immunodeficiency virus (HIV). Tinea unguium associated with AIDS is characterized by being clinically more aggressive and therapeutically more difficult to treat than in the general population. Terbinafine is considered to be a first-choice option for the treatment of dermatophyte onychomycosis in immunocompetent individuals. This drug has been used in a series of 21 HIV-positive patients diagnosed with tinea unguium for 1 year in the University Hospital La Paz, Madrid. All patients underwent a subsequent clinical follow-up for 6 months. The results showed a high percentage of clinical and mycological cures, as well as maintenance of the response after follow-up; no drug interactions or significant adverse effects related to the drug under study were recorded.

  2. Innate versus acquired immune response in the pathogenesis of recurrent idiopathic pericarditis.

    PubMed

    Cantarini, Luca; Luca, Cantarini; Imazio, Massimo; Massimo, Imazio; Brucato, Antonio; Antonio, Brucato; Lucherini, Orso Maria; Maria, Lucherini Orso; Galeazzi, Mauro; Mauro, Galeazzi

    2010-04-01

    The pathogenesis of recurrent pericarditis is still poorly understood and may be related either to viral infections or autoimmune and autoinflammatory disorders. The immune system plays a major role in the pathogenesis of the disease, modulating individual responses to different noxa and explaining the variable reported recurrence rate (ranging from 20% to 50% of patients) following an attack of acute or recurrent pericarditis. Increasing interest is currently being devoted to autoinflammatory disorders, a group of conditions characterized by spontaneously relapsing and remitting bouts of systemic inflammation without apparent involvement of antigen-specific T cells or significant production of auto-antibodies. Ongoing basic and clinical research is needed to provide further evidence for the understanding of this common and troublesome disease, and to develop targeted and more efficacious therapies.

  3. Evaluation of the Protective Immunity of a Novel Subunit Fusion Vaccine in a Murine Model of Systemic MRSA Infection

    PubMed Central

    Zuo, Qian-Fei; Yang, Liu-Yang; Feng, Qiang; Lu, Dong-Shui; Dong, Yan-Dong; Cai, Chang-Zhi; Wu, Yi; Guo, Ying; Gu, Jiang; Zeng, Hao; Zou, Quan-Ming

    2013-01-01

    Staphylococcus aureus is a common commensal organism in humans and a major cause of bacteremia and hospital acquired infection. Because of the spread of strains resistant to antibiotics, these infections are becoming more difficult to treat. Therefore, exploration of anti-staphylococcal vaccines is currently a high priority. Iron surface determinant B (IsdB) is an iron-regulated cell wall-anchored surface protein of S. aureus. Alpha-toxin (Hla) is a secreted cytolytic pore-forming toxin. Previous studies reported that immunization with IsdB or Hla protected animals against S. aureus infection. To develop a broadly protective vaccine, we constructed chimeric vaccines based on IsdB and Hla. Immunization with the chimeric bivalent vaccine induced strong antibody and T cell responses. When the protective efficacy of the chimeric bivalent vaccine was compared to that of individual proteins in a murine model of systemic S. aureus infection, the bivalent vaccine showed a stronger protective immune response than the individual proteins (IsdB or Hla). Based on the results presented here, the chimeric bivalent vaccine affords higher levels of protection against S. aureus and has potential as a more effective candidate vaccine. PMID:24324681

  4. Evaluation of the protective immunity of a novel subunit fusion vaccine in a murine model of systemic MRSA infection.

    PubMed

    Zuo, Qian-Fei; Yang, Liu-Yang; Feng, Qiang; Lu, Dong-Shui; Dong, Yan-Dong; Cai, Chang-Zhi; Wu, Yi; Guo, Ying; Gu, Jiang; Zeng, Hao; Zou, Quan-Ming

    2013-01-01

    Staphylococcus aureus is a common commensal organism in humans and a major cause of bacteremia and hospital acquired infection. Because of the spread of strains resistant to antibiotics, these infections are becoming more difficult to treat. Therefore, exploration of anti-staphylococcal vaccines is currently a high priority. Iron surface determinant B (IsdB) is an iron-regulated cell wall-anchored surface protein of S. aureus. Alpha-toxin (Hla) is a secreted cytolytic pore-forming toxin. Previous studies reported that immunization with IsdB or Hla protected animals against S. aureus infection. To develop a broadly protective vaccine, we constructed chimeric vaccines based on IsdB and Hla. Immunization with the chimeric bivalent vaccine induced strong antibody and T cell responses. When the protective efficacy of the chimeric bivalent vaccine was compared to that of individual proteins in a murine model of systemic S. aureus infection, the bivalent vaccine showed a stronger protective immune response than the individual proteins (IsdB or Hla). Based on the results presented here, the chimeric bivalent vaccine affords higher levels of protection against S. aureus and has potential as a more effective candidate vaccine.

  5. Hepatitis B: progress in understanding chronicity, the innate immune response, and cccDNA protection

    PubMed Central

    Shimazaki, Tomoe; Takeda, Rei; Izumi, Takaaki; Umumura, Machiko; Sakamoto, Naoya

    2016-01-01

    Hepatitis B virus (HBV) infection is a serious health threat around the world. Despite the availability of an effective hepatitis B vaccine, the number of HBV carriers is estimated to be as high as 240 million worldwide. Global mortality due to HBV-related liver diseases such as chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC) may be as high as 1 million deaths per year. HBV is transmitted via blood and body fluids, and is much more infectious than both human immunodeficiency virus (HIV) and hepatitis C virus. While HBV infection exhibits a variety of clinical presentations, even asymptomatic carriers can develop HCC without liver fibrosis. Current therapeutic options against HBV include pegylated interferon (Peg-IFN) and nucleos(t)ide reverse transcriptase inhibitors (NRTIs), with clinical studies showing a significant association between loss of HBV DNA and a decrease in cancer risk. However, the ultimate goal of HBV therapy is a complete cure of HBV—including the elimination of covalently closed circular DNA (cccDNA)—in order to further decrease the risk of developing HCC. The development of hepatitis B is associated with the host immune response to virus-infected hepatocytes, as HBV is understood to lack direct cytotoxicity. While HBV-specific CD8+ T cells are thus involved in hepatitis development, they also play an important role in eliminating HBV infection. Indeed, the innate immune response during the initial phase of HBV infection is essential to the induction of acquired immunity. However, the innate immune response to HBV infection, including the roles of specific immunocompetent cells and associated molecules, is not well understood. In this review, we focus on the current understanding of the mechanisms underlying hepatitis development by HBV infection. We also address the mechanisms by which HBV protects cccDNA. PMID:27761441

  6. T-Cell Immune Response Assessment as a Complement to Serology and Intranasal Protection Assays in Determining the Protective Immunity Induced by Acellular Pertussis Vaccines in Mice

    PubMed Central

    Ausiello, C. M.; Lande, R.; Stefanelli, P.; Fazio, C.; Fedele, G.; Palazzo, R.; Urbani, F.; Mastrantonio, P.

    2003-01-01

    The relative value of antibodies and/or T-cell immune responses to Bordetella pertussis antigens in the immunity induced by acellular pertussis (aP) vaccines is still an open issue, probably due to the incomplete knowledge on the mechanisms of protective immunity to pertussis. The relevance of T-cell immune responses in protection from pertussis has been demonstrated in murine and human models of infection; thus, in this study, the ability of different vaccine preparations of three component (pertussis toxin, filamentous hemagglutinin, and pertactin) aP vaccines to induce T-cell responses was investigated in mice. All vaccine preparations examined passed the immunogenicity control test, based on antibody titer assessment, according to European Pharmacopoeia standards, and protected mice from B. pertussis intranasal challenge, but not all preparations were able to prime T cells to pertussis toxin, the specific B. pertussis antigen. In particular, one vaccine preparation was unable to induce proliferation and gamma interferon (IFN-γ) production while the other two gave borderline results. The evaluation of T-cell responses to pertussis toxin antigen may provide information on the protective immunity induced by aP vaccines in animal models. Considering the critical role of the axis interleukin-12-IFN-γ for protection from pertussis, our results suggest that testing the induction of a key protective cytokine such as IFN-γ could be an additional tool for the evaluation of the immune response induced by aP vaccines. PMID:12853397

  7. Plasmodesmata Localizing Proteins Regulate Transport and Signaling during Systemic Acquired Immunity in Plants.

    PubMed

    Lim, Gah-Hyun; Shine, M B; de Lorenzo, Laura; Yu, Keshun; Cui, Weier; Navarre, Duroy; Hunt, Arthur G; Lee, Jung-Youn; Kachroo, Aardra; Kachroo, Pradeep

    2016-04-13

    Systemic acquired resistance (SAR) in plants is mediated by the signaling molecules azelaic acid (AzA), glycerol-3-phosphate (G3P), and salicylic acid (SA). Here, we show that AzA and G3P transport occurs via the symplastic route, which is regulated by channels known as plasmodesmata (PD). In contrast, SA moves via the extracytosolic apoplast compartment. We found that PD localizing proteins (PDLP) 1 and 5 were required for SAR even though PD permeability in pdlp1 and 5 mutants was comparable to or higher than wild-type plants, respectively. Furthermore, PDLP function was required in the recipient cell, suggesting regulatory function in SAR. Interestingly, overexpression of PDLP5 drastically reduced PD permeability, yet also impaired SAR. PDLP1 interacted with AZI1 (lipid transfer-like protein required for AzA- and G3P-induced SAR) and contributed to its intracellular partitioning. Together, these results reveal the transport routes of SAR chemical signals and highlight the regulatory role of PD-localizing proteins in SAR. PMID:27078071

  8. Anaplastic lymphoma kinase negative anaplastic large cell lymphoma of hard palate as first clinical manifestation of acquired immune deficiency syndrome

    PubMed Central

    Narwal, Anjali; Yadav, Achla Bharti; Prakash, Sant; Gupta, Shally

    2016-01-01

    Anaplastic large cell lymphoma (ALCL) is an uncommon disease, accounting for <5% of all cases of non-Hodgkin's lymphoma. We report a case of 48-year-old male who presented a clinically benign swelling in the right anterior palatal region since last 2 months. Radiographic evaluation showed no bone loss in palatal area. Histological and radiological examination was in favor of a peripheral reactive lesion like pyogenic granuloma or a benign salivary gland tumor. Immunohistochemistry confirmed the diagnosis of anaplastic lymphoma kinase-negative (ALK(−)) ALCL. Further laboratory tests ELISA for human immunodeficiency virus (HIV) and CD4 cell count was done which showed positivity for HIV. To the best of our knowledge, it is the first case of ALK(−) ALCL in the hard palate presenting as the first clinical manifestation of acquired immune deficiency syndrome. PMID:27041916

  9. Anaplastic lymphoma kinase negative anaplastic large cell lymphoma of hard palate as first clinical manifestation of acquired immune deficiency syndrome.

    PubMed

    Narwal, Anjali; Yadav, Achla Bharti; Prakash, Sant; Gupta, Shally

    2016-01-01

    Anaplastic large cell lymphoma (ALCL) is an uncommon disease, accounting for <5% of all cases of non-Hodgkin's lymphoma. We report a case of 48-year-old male who presented a clinically benign swelling in the right anterior palatal region since last 2 months. Radiographic evaluation showed no bone loss in palatal area. Histological and radiological examination was in favor of a peripheral reactive lesion like pyogenic granuloma or a benign salivary gland tumor. Immunohistochemistry confirmed the diagnosis of anaplastic lymphoma kinase-negative (ALK(-)) ALCL. Further laboratory tests ELISA for human immunodeficiency virus (HIV) and CD4 cell count was done which showed positivity for HIV. To the best of our knowledge, it is the first case of ALK(-) ALCL in the hard palate presenting as the first clinical manifestation of acquired immune deficiency syndrome. PMID:27041916

  10. Anaplastic lymphoma kinase negative anaplastic large cell lymphoma of hard palate as first clinical manifestation of acquired immune deficiency syndrome.

    PubMed

    Narwal, Anjali; Yadav, Achla Bharti; Prakash, Sant; Gupta, Shally

    2016-01-01

    Anaplastic large cell lymphoma (ALCL) is an uncommon disease, accounting for <5% of all cases of non-Hodgkin's lymphoma. We report a case of 48-year-old male who presented a clinically benign swelling in the right anterior palatal region since last 2 months. Radiographic evaluation showed no bone loss in palatal area. Histological and radiological examination was in favor of a peripheral reactive lesion like pyogenic granuloma or a benign salivary gland tumor. Immunohistochemistry confirmed the diagnosis of anaplastic lymphoma kinase-negative (ALK(-)) ALCL. Further laboratory tests ELISA for human immunodeficiency virus (HIV) and CD4 cell count was done which showed positivity for HIV. To the best of our knowledge, it is the first case of ALK(-) ALCL in the hard palate presenting as the first clinical manifestation of acquired immune deficiency syndrome.

  11. Acquired resistance to innate immune clearance promotes Klebsiella pneumoniae ST258 pulmonary infection

    PubMed Central

    Ahn, Danielle; Peñaloza, Hernán; Wang, Zheng; Wickersham, Matthew; Parker, Dane; Patel, Purvi; Koller, Antonius; Chen, Emily I.; Bueno, Susan M.; Uhlemann, Anne-Catrin; Prince, Alice

    2016-01-01

    Adaptive changes in the genome of a locally predominant clinical isolate of the multidrug-resistant Klebsiella pneumoniae ST258 (KP35) were identified and help to explain the selection of this strain as a successful pulmonary pathogen. The acquisition of 4 new ortholog groups, including an arginine transporter, enabled KP35 to outcompete related ST258 strains lacking these genes. KP35 infection elicited a monocytic response, dominated by Ly6Chi monocytic myeloid-derived suppressor cells that lacked phagocytic capabilities, expressed IL-10, arginase, and antiinflammatory surface markers. In comparison with other K. pneumoniae strains, KP35 induced global changes in the phagocytic response identified with proteomics, including evasion of Ca2+ and calpain activation necessary for phagocytic killing, confirmed in functional studies with neutrophils. This comprehensive analysis of an ST258 K. pneumoniae isolate reveals ongoing genetic adaptation to host microenvironments and innate immune clearance mechanisms that complements its repertoire of antimicrobial resistance genes and facilitates persistence in the lung. PMID:27777978

  12. Immune endocrinological evaluation in patients with severe vascular acquired brain injuries: therapeutical approaches.

    PubMed

    Amico, Angelo Paolo; Terlizzi, Annamaria; Annamaria, Terlizzi; Megna, Marisa; Marisa, Megna; Megna, Gianfranco; Gianfranco, Megna; Damiani, Sabino; Sabino, Damiani

    2013-06-01

    It is known that in severe acquired brain injuries there is process of neuroinflammation, with the activation of a local and general stress response. In our study we considered six patients with disorders of consciousness (five in vegetative state and one in minimal consciousness state) in subacute phase, which had both a clinical assessment and a functional imaging (fMRI): in all these patients we analised blood levels of osteopontin (OPN), a cytokin involved in neuroinflammation but also in neurorepair with a still discussed role. Besides we studied the lymphocyte subsets and blood levels of some hormones (ADH, ACTH, PRL, GH, TSH, fT3, fT4). We found a positive correlation between the levels of serum osteopontin (higher than normal in all subjects) and the severity of the brain injury, especially for prognosis: actually, the patient with the lowest level has emerged from minimal consciousness state, while the one with the highest level has died a few days after the evaluation. The lymphocyte subset was altered, with a general increase of CD4+/CD3+ ratio, but without a so strict correlation with clinical severity; the only hormone with a significant increase in the worse patients was prolactin. In fMRI we detected some responses to visual and acoustic stimuli also in vegetative states, which had no clinical response to this kind of stimulation but generally have had a better prognosis. So we conclude that osteopontin could be a good marker of neuroinflammation and relate to a worse prognosis of brain injuries; the lymphocyte alterations in these disorders are not clear, but we suspect an unbalance of CD4 towards Th2; PRL is the best endocrinological marker of brain injury severity; fMRI surely plays an important role in the detection of subclinical responses and in prognostic stratification, that is still to define with more studies and statistical analysis.

  13. Protect the Circle of Life: Immunize Our Nations

    MedlinePlus

    ... Children (VFC) Stop Transmission of Polio (STOP) Vaccine Management Business Improvement Project (VMBIP) Global Immunizations & Vaccinations Immunization Program Evaluation (IPE) Assessment, Feedback, Incentives, and Exchange (AFIX) Comprehensive Clinic Assessment Software Application (CoCASA) Instant ...

  14. Maternally acquired IgG immunity in neonates born to renal transplanted women.

    PubMed

    Viana, Patrícia Oliveira; Ono, Erika; Dinelli, Maria Isabel Saraiva; Costa-Carvalho, Beatriz Tavares; Santos, Amélia Miyashiro Nunes Dos; Sass, Nelson; Moraes-Pinto, Maria Isabel de

    2015-06-17

    Neonates born to renal transplanted women are exposed in utero to immunosuppressors and to antenatal conditions that may predispose the neonate to a high risk of prematurity and intrauterine growth retardation. These factors might interfere with the transfer of maternal IgG immunity. Total IgG levels and specific antibodies to measles, varicella, tetanus, Haemophilus influenzae type b (Hib) and Streptococcus pneumoniae (serotypes 4,6B,9V,14,18C,19F and 23F) were evaluated on maternal and cord blood samples of 23 sets of renal transplanted women and their newborns and 32 sets of healthy women-newborns at term. Total IgG levels were measured by nephelometry and specific antibodies, by ELISA. Renal transplanted mothers had lower median tetanus antibodies (0.67IU/mL) than controls (1.53IU/mL; p=0.017). Neonates from renal transplanted mothers had lower median tetanus antibodies (0.95IU/mL) than controls (1.97IU/mL, p=0.008). Antibodies to measles, varicella, Hib and the 7 serotypes of S. pneumoniae were similar between groups. Maternal antibodies were associated with an increase in neonatal antibodies for all antigens; gestational age was associated with an increase in Hib neonatal antibodies. Preeclampsia was associated with a decrease in neonatal total IgG and serotype 4 S. pneumoniae antibodies; chronic hypertension was associated with a decrease in neonatal serotype 6B S. pneumoniae antibodies. As neonates from transplanted women may be born with lower tetanus antibodies than controls, efforts should be made to keep maternal vaccines up-to-date. Clinical antenatal care with control of preeclampsia, chronic hypertension and prevention of premature delivery might also contribute to neonatal antibody levels to specific antigens at birth. PMID:25987539

  15. Effect of traditional Chinese medicine for treating human immunodeficiency virus infections and acquired immune deficiency syndrome: Boosting immune and alleviating symptoms.

    PubMed

    Zou, Wen; Wang, Jian; Liu, Ying

    2016-01-01

    To respond to the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) epidemic in China, the integration of antiretroviral therapy (ART) and traditional Chinese medicine (TCM) has important implications in health outcomes, especially in China where the use of TCM is widespread. The National Free TCM Pilot Program for HIV Infected People began in 5 provinces (Henan, Hebei, Anhui, Hubei, and Guangdong) in 2004, and quickly scaled up to 19 provinces, autonomous regions, and municipalities in China including some places with high prevalence, 26,276 adults have been treated thus far. Usually, people with HIV infection seek TCM for four main reasons: to enhance immune function, to treat symptoms, to improve quality of life, and to reduce side effects related to medications. Evidences from randomized controlled clinical trials suggested some beneficial effects of use of traditional Chinese herbal medicine for HIV infections and AIDS. More proofs from large, well-designed, rigorous trials is needed to give firm support. Challenges include interaction between herbs and antiretroviral drugs, stigma and discrimination. The Free TCM Program has made considerable progress in providing the necessary alternative care and treatment for HIV-infected people in China, and has strong government support for continued improvement and expansion, establishing and improving a work mechanism integrating Chinese and Western medicines.

  16. Effect of traditional Chinese medicine for treating human immunodeficiency virus infections and acquired immune deficiency syndrome: Boosting immune and alleviating symptoms.

    PubMed

    Zou, Wen; Wang, Jian; Liu, Ying

    2016-01-01

    To respond to the human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) epidemic in China, the integration of antiretroviral therapy (ART) and traditional Chinese medicine (TCM) has important implications in health outcomes, especially in China where the use of TCM is widespread. The National Free TCM Pilot Program for HIV Infected People began in 5 provinces (Henan, Hebei, Anhui, Hubei, and Guangdong) in 2004, and quickly scaled up to 19 provinces, autonomous regions, and municipalities in China including some places with high prevalence, 26,276 adults have been treated thus far. Usually, people with HIV infection seek TCM for four main reasons: to enhance immune function, to treat symptoms, to improve quality of life, and to reduce side effects related to medications. Evidences from randomized controlled clinical trials suggested some beneficial effects of use of traditional Chinese herbal medicine for HIV infections and AIDS. More proofs from large, well-designed, rigorous trials is needed to give firm support. Challenges include interaction between herbs and antiretroviral drugs, stigma and discrimination. The Free TCM Program has made considerable progress in providing the necessary alternative care and treatment for HIV-infected people in China, and has strong government support for continued improvement and expansion, establishing and improving a work mechanism integrating Chinese and Western medicines. PMID:26577109

  17. Partial Protection against Brucella Infection in Mice by Immunization with Nonpathogenic Alphaproteobacteria▿

    PubMed Central

    Delpino, M. Victoria; Estein, Silvia M.; Fossati, Carlos A.; Baldi, Pablo C.

    2007-01-01

    Previous findings indicate that Brucella antigens and those from nonpathogenic alphaproteobacteria (NPAP) are cross-recognized by the immune system. We hypothesized that immunization with NPAP would protect mice from Brucella infection. Mice were immunized subcutaneously with heat-killed Ochrobactrum anthropi, Sinorhizobium meliloti, Mesorhizobium loti, Agrobacterium tumefaciens, or Brucella melitensis H38 (standard positive control) before intravenous challenge with Brucella abortus 2308. Cross-reacting serum antibodies against Brucella antigens were detected at the moment of challenge in all NPAP-immunized mice. Thirty days after B. abortus challenge, splenic CFU counts were significantly lower in mice immunized with O. anthropi, M. loti, and B. melitensis H38 than in the phosphate-buffered saline controls (protection levels were 0.80, 0.66, and 1.99 log units, respectively). In mice immunized intraperitoneally with cytosoluble extracts from NPAP or Brucella abortus, protection levels were 1.58 for the latter, 0.63 for O. anthropi, and 0.40 for M. loti. To test whether the use of live NPAP would increase protection further, mice were both immunized and challenged by the oral route. Immunization with NPAP induced a significant increase in serum immunoglobulin G (IgG), but not serum or fecal IgA, against Brucella antigens. After challenge, anti-Brucella IgA increased significantly in the sera and feces of mice orally immunized with O. anthropi. For all NPAP, protection levels were higher than those obtained with systemic immunizations but were lower than those obtained by oral immunization with heat-killed B. abortus. These results show that immunization with NPAP, especially O. anthropi, confers partial protection against Brucella challenge. However, such protection is lower than that conferred by immunization with whole Brucella or its cytosoluble fraction. PMID:17715332

  18. Experimental cutaneous leishmaniasis. V. Protective immunity in subclinical and self-healing infection in the mouse.

    PubMed Central

    Preston, P M; Dumonde, D C

    1976-01-01

    This study shows how infection of CBA mice with L. tropica can be manipulated so as to mimic the principal features of both subclinical and self-healing cutaneous leishmaniasis in man. CBA mice were infected with graded inocula of L. tropica promastigotes. The pattern of primary infection was found to be dependent on dose of infecting organisms: mice given low dose inocula (10(2), 10(3)) developed subclinical infections; those given high dose inocula (10(4), 10(5), 10(6)) developed overt, clinical lesions. Size and duration of lesions, and antibody production were directly proportional to dose; delayed hypersensitivity responses were inversely proportional to dose. Protective immunity to challenge infection was induced by both subclinical and clinical infection; and was manifest both during and after the healing stages of primary lesions. Protective immunity was also induced by artificial immunization with sonicated promastigotes in adjuvants but was only manifest if the challenge dose was not too large. The course of challenge infections differed depending on the method of immunization, i.e. whether by infection or artificial immunization. Lymphoid cells from immune CBA mice conferred protection on recipient syngeneic CBA mice against challenge infection; serum from immune mice did not, but suspension of immune peritoneal cells in immune serum enhanced their protective capacity. The experimental induction of protective immunity by low-dose infection, without a clinical allergic response at the site of inoculation, is of importance in designing an immunoprophylactic approach to human leishmaniasis. PMID:1261086

  19. Protective immunity against recurrent Staphylococcus aureus skin infection requires antibody and interleukin-17A.

    PubMed

    Montgomery, Christopher P; Daniels, Melvin; Zhao, Fan; Alegre, Maria-Luisa; Chong, Anita S; Daum, Robert S

    2014-05-01

    Although many microbial infections elicit an adaptive immune response that can protect against reinfection, it is generally thought that Staphylococcus aureus infections fail to generate protective immunity despite detectable T and B cell responses. No vaccine is yet proven to prevent S. aureus infections in humans, and efforts to develop one have been hampered by a lack of animal models in which protective immunity occurs. Our results describe a novel mouse model of protective immunity against recurrent infection, in which S. aureus skin and soft tissue infection (SSTI) strongly protected against secondary SSTI in BALB/c mice but much less so in C57BL/6 mice. This protection was dependent on antibody, because adoptive transfer of immune BALB/c serum or purified antibody into either BALB/c or C57BL/6 mice resulted in smaller skin lesions. We also identified an antibody-independent mechanism, because B cell-deficient mice were partially protected against secondary S. aureus SSTI and adoptive transfer of T cells from immune BALB/c mice resulted in smaller lesions upon primary infection. Furthermore, neutralization of interleukin-17A (IL-17A) abolished T cell-mediated protection in BALB/c mice, whereas neutralization of gamma interferon (IFN-γ) enhanced protection in C57BL/6 mice. Therefore, protective immunity against recurrent S. aureus SSTI was advanced by antibody and the Th17/IL-17A pathway and prevented by the Th1/IFN-γ pathway, suggesting that targeting both cell-mediated and humoral immunity might optimally protect against secondary S. aureus SSTI. These findings also highlight the importance of the mouse genetic background in the development of protective immunity against S. aureus SSTI.

  20. Protection against mortality due to Vibrio cholerae infection in infant rabbits caused by immunization of mothers with cholera protective antigen.

    PubMed

    Sciortino, C V

    1996-03-01

    Vaccination of female rabbits with cholera protective antigen (CPA) protected their F1 progeny from lethal challenge with Vibrio cholerae. Protection was determined by the choleragenic score and survival rates. Serum and milk IgG, IgM, IgA titres to CPA, cholera toxin, and LPS were determined. At 8 and 20 weeks post-immunization, mothers' milk, sera, and infants' sera showed elevated CPA-specific IgG and IgA, and infants were protected. Mothers' serum and milk antibody remained elevated for 36 weeks. At 26 weeks, mothers were re-bred, but their progeny were swapped and cross-fed. Infants born to the placebo-vaccinated mothers and nursed by CPA-immune nannies were partially protected from challenge. Infants born to CPA-immune mothers and cross-fed by the placebo-vaccinated nannies were less protected. CPA stimulated both transplacental and milk antibody, but passive immunity was primarily milk-derived. A 36-week booster vaccine stimulated an anamnestic serological response that did not provide protection equivalent to the original vaccine. CPA provided partial protective immunity to the milk-fed infant rabbits that suggests that CPA may be important in the development of a cholera vaccine.

  1. Pulmonary leukocytic responses are linked to the acquired immunity of mice vaccinated with irradiated cercariae of Schistosoma mansoni

    SciTech Connect

    Aitken, R.; Coulson, P.S.; Wilson, R.A.

    1988-05-15

    Pulmonary cellular responses in C57BL/6 mice exposed to Schistosoma mansoni have been investigated by sampling cells from the respiratory airways with bronchoalveolar lavage. Mice exposed to cercariae attenuated with 20 krad gamma-radiation developed stronger and more persistent pulmonary leukocytic responses than animals exposed to equal numbers of normal parasites. Although vaccination with irradiated cercariae also stimulated T cell responses of greater magnitude and duration than normal infection, the lymphocytic infiltrate elicited by each regimen did not differ substantially in its composition, 5 wk after exposure. Studies with cercariae attenuated by different treatments established that a link exists between the recruitment of leukocytes to the lungs of vaccinated mice and resistance to reinfection. There was a strong association between pulmonary leukocytic responses and the elimination of challenge infections by vaccinated mice. Animals exposed to irradiated cercariae of S. mansoni were resistant to homologous challenge infection but were not protected against Schistosoma margrebowiei. Homologous challenge of vaccinated mice stimulated anamnestic leukocytic and T lymphocytic responses in the lungs, 2 wk postinfection, but exposure of immunized animals to the heterologous species failed to trigger an expansion in these populations of cells. Our studies indicate that pulmonary leukocytes and T lymphocytes are intimately involved in the mechanism of vaccine-induced resistance to S. mansoni. It remains unclear whether these populations of cells initiate protective inflammatory reactions against challenge parasites in the lungs, or accumulate in response to the activation of the protective mechanism by other means.

  2. Plasmodium vivax Reticulocyte Binding Proteins Are Key Targets of Naturally Acquired Immunity in Young Papua New Guinean Children

    PubMed Central

    França, Camila T.; He, Wen-Qiang; Gruszczyk, Jakub; Lim, Nicholas T. Y.; Lin, Enmoore; Kiniboro, Benson; Siba, Peter M.; Tham, Wai-Hong

    2016-01-01

    Background Major gaps in our understanding of Plasmodium vivax biology and the acquisition of immunity to this parasite hinder vaccine development. P. vivax merozoites exclusively invade reticulocytes, making parasite proteins that mediate reticulocyte binding and/or invasion potential key vaccine or drug targets. While protein interactions that mediate invasion are still poorly understood, the P. vivax Reticulocyte-Binding Protein family (PvRBP) is thought to be involved in P. vivax restricted host-cell selectivity. Methodology/Principal findings We assessed the binding specificity of five members of the PvRBP family (PvRBP1a, PvRBP1b, PvRBP2a, PvRBP2b, PvRBP2-P2 and a non-binding fragment of PvRBP2c) to normocytes or reticulocytes. PvRBP2b was identified as the only reticulocyte-specific binder (P<0.001), whereas the others preferentially bound to normocytes (PvRBP1a/b P≤0.034), or showed comparable binding to both (PvRBP2a/2-P2, P = 0.38). Furthermore, we measured levels of total and IgG subclasses 1, 2, 3 and 4 to the six PvRBPs in a cohort of young Papua New Guinean children, and assessed their relationship with prospective risk of P. vivax malaria. Children had substantial, highly correlated (rho = 0.49–0.82, P<0.001) antibody levels to all six PvRBPs, with dominant IgG1 and IgG3 subclasses. Both total IgG (Incidence Rate Ratio [IRR] 0.63–0.73, P = 0.008–0.041) and IgG1 (IRR 0.56–0.69, P = 0.001–0.035) to PvRBP2b and PvRBP1a were strongly associated with reduced risk of vivax-malaria, independently of age and exposure. Conclusion/Significance These results demonstrate a diversity of erythrocyte-binding phenotypes of PvRBPs, indicating binding to both reticulocyte-specific and normocyte-specific ligands. Our findings provide further insights into the naturally acquired immunity to P. vivax and highlight the importance of PvRBP proteins as targets of naturally acquired humoral immunity. In-depth studies of the role of PvRBPs in P. vivax invasion and

  3. Protective efficacy and immune responses by homologous prime-booster immunizations of a novel inactivated Salmonella Gallinarum vaccine candidate

    PubMed Central

    2016-01-01

    Purpose Salmonella enterica serovar Gallinarum (SG) ghost vaccine candidate was recently constructed. In this study, we evaluated various prime-boost vaccination strategies using the candidate strain to optimize immunity and protection efficacy against fowl typhoid. Materials and Methods The chickens were divided into five groups designated as group A (non-immunized control), group B (orally primed and boosted), group C (primed orally and boosted intramuscularly), group D (primed and boosted intramuscularly), and group E (primed intramuscularly and boosted orally). The chickens were primed with the SG ghost at 7 days of age and were subsequently boosted at the fifth week of age. Post-immunization, the plasma IgG and intestinal secretory IgA (sIgA) levels, and the SG antigen-specific lymphocyte stimulation were monitored at weekly interval and the birds were subsequently challenged with a virulent SG strain at the third week post-second immunization. Results Chickens in group D showed an optimized protection with significantly increased plasma IgG, sIgA, and lymphocyte stimulation response compared to all groups. The presence of CD4+ and CD8+ T cells and monocyte/macrophage (M/M) in the spleen, and splenic expression of cytokines such as interferon γ (IFN-γ) and interleukin 6 (IL-6) in the immunized chickens were investigated. The prime immunization induced significantly higher splenic M/M population and mRNA levels of IFN-γ whereas the booster showed increases of splenic CD4+ and CD8+ T-cell population and IL-6 cytokine in mRNA levels. Conclusion Our results indicate that the prime immunization with the SG ghost vaccine induced Th1 type immune response and the booster elicited both Th1- and Th2-related immune responses. PMID:27489805

  4. Is Sovereign Immunity Archaic? Protections for Colleges and Universities Continue to Erode.

    ERIC Educational Resources Information Center

    Broadhurst, Arthur G.

    1996-01-01

    Public college and university administrators are concerned about steady erosion of immunities and tort caps traditionally relied upon for protection against lawsuits. In this context, institutions must consider their protection in these areas: extension of protection to all employees; scope of employment; nongovernmental functions; foundations and…

  5. Use of a Sindbis virus DNA-based expression vector for induction of protective immunity against pseudorabies virus in pigs.

    PubMed

    Dufour, Vinciane; De Boisséson, Claire

    2003-06-20

    Injection of plasmid DNA encoding pseudorabies virus (PRV) glycoproteins into pig muscle has been shown to result in protective immunity against lethal infection. Nevertheless, such DNA vaccines are still less efficient than some attenuated or killed live vaccines. One way to increase DNA vaccine efficacy is to improve the vectorisation system at the molecular level, thereby enhancing the rate of in vivo-produced immunogen protein and consequently specific acquired immunity. The present study compared the effectiveness of the protein expression system depending on Sindbis virus (SIN) replicase [J. Virol. 70 (1996) 508] with that of more classical pcDNA3 plasmid. Pigs were vaccinated twice at 3-week interval with a mixture of three pcDNA3 plasmids expressing gB, gC and gD (designated as PRV-pcDNA3) or a mixture of three SIN plasmids expressing the same glycoproteins (PRV-pSINCP), and were challenged with a highly virulent PRV strain. The two DNA vaccines induced PRV-specific T cell-mediated immune response characterized by very low levels of IFN-gamma mRNA in PBMC after in vitro antigen-specific stimulation. Very low levels of neutralizing antibodies (NAb) were also obtained in sera following DNA injection(s). A second DNA injection did not boost immune responses. After a lethal challenge, high levels of IFN-gamma mRNA and high NAb response were induced in all DNA-vaccinated pigs, regardless of the vector used. Therefore, the two eukaryotic expression systems showed comparable efficacy in inducing antiviral immunity and clinical protection against PRV in pigs. This suggests that SIN DNA-based vector immunizing potential may differ according to antigen and/or host. PMID:12814698

  6. Health related quality of life: is it another comprehensive evaluation indicator of Chinese medicine on acquired immune deficiency syndrome treatment?

    PubMed

    Liu, Zhibin; Yang, Jiping

    2015-10-01

    Health related quality of life (HRQOL) can better reflect changes in acquired immune deficiency syndrome (AIDS) patients and inform economic evaluation of AIDS treatment services, and the assessment of HRQOL can help us to detect problems that may influence the progression of the disease, hence HRQOL has become a particularly important assessment indictor for HIV comprehensive interventions. Being a multi-angle, multi-level, and diversified complex intervention, roles of Chinese medicine (CM) in AIDS treatment have been recognized and accepted by more and more patients, and HRQOL has been widely used to evaluate the comprehensive management effects of CM on AIDS. In this article, the authors analyze the definition and measurement of HRQOL, measurement of HRQOL of HIV/AIDS patients and effects of CM on AIDS, and give some reasonable advices for the usage of the scale of HRQOL. The authors hold that some new HRQOL instruments specific for CM treatment of AIDS should be developed and further prospective studies should be carried out to demonstrate the practicality, reliability and validity of HRQOL as an evaluation indictor for CM treatment of AIDS.

  7. Protective Immunity and Defects in the Neonatal and Elderly Immune Response to Sepsis

    PubMed Central

    Gentile, Lori F.; Nacionales, Dina C.; Lopez, M. Cecilia; Vanzant, Erin; Cuenca, Angela; Cuenca, Alex G.; Ungaro, Ricardo; Szpila, Ben E.; Larson, Shawn; Joseph, Anna; Moore, Frederick; Leeuwenburgh, Christiaan; Baker, Henry V.; Moldawer, Lyle L.; Efron, Philip A.

    2014-01-01

    Populations encompassing extremes of age, including neonates and elderly, have greater mortality from sepsis. We propose that the increased mortality observed in the neonatal and elderly populations after sepsis is due to fundamental differences in host protective immunity, and are manifested at the level of the leukocyte transcriptome. Neonatal (5–7 days), young adult (6–12 weeks), or elderly (20–24 months) mice underwent a cecal slurry model of intra-abdominal sepsis. Both neonatal and elderly mice exhibited significantly greater mortality to sepsis (p<0.05). Neonates in particular exhibited significant attenuation of their inflammatory response (p<0.05), as well as reductions in cell recruitment and reactive oxygen species production (both p<0.05), all of which could be confirmed at the level of the leukocyte transcriptome. In contrast elderly mice were also more susceptible to abdominal peritonitis, but this was associated with no significant differences in the magnitude of the inflammatory response, reduced bacterial killing (p<0.05), reduced early myeloid cell activation (p<0.05) and a persistent inflammatory response that failed to resolve. Interestingly, elderly mice expressed a persistent inflammatory and immunosuppressive response at the level of the leukocyte transcriptome, with failure to return to baseline by three days. This study reveals that neonatal and elderly mice have profoundly different responses to sepsis that are manifested at the level of their circulating leukocyte transcriptome, although the net result of increased mortality, is similar. Considering these differences are fundamental aspects of the genomic response to sepsis, interventional therapies will require individualization based on the age of the population. PMID:24591376

  8. Primary Babesia rodhaini infection followed by recovery confers protective immunity against B. rodhaini reinfection and Babesia microti challenge infection in mice.

    PubMed

    Wang, Guanbo; Efstratiou, Artemis; Adjou Moumouni, Paul Franck; Liu, Mingming; Jirapattharasate, Charoonluk; Guo, Huanping; Gao, Yang; Cao, Shinuo; Zhou, Mo; Suzuki, Hiroshi; Igarashi, Ikuo; Xuan, Xuenan

    2016-10-01

    In the present study, we investigated the protective immunity against challenge infections with Babesia rodhaini and Babesia microti in the mice recovered from B. rodhaini infection. Six groups with 5 test mice in each group were used in this study, and were intraperitoneally immunized with alive and dead B. rodhaini. The challenge infections with B. rodhaini or B. microti were performed using different time courses. Our results showed that the mice recovered from primary B. rodhaini infection exhibited low parasitemia and no mortalities after the challenge infections, whereas mock mice which had received no primary infection showed a rapid increase of parasitemia and died within 7 days after the challenge with B. rodhaini. Mice immunized with dead B. rodhaini were not protected against either B. rodhaini or B. microti challenge infections, although high titers of antibody response were induced. These results indicate that only mice immunized with alive B. rodhaini could acquire protective immunity against B. rodhaini or B. microti challenge infection. Moreover, the test mice produced high levels of antibody response and low levels of cytokines (INF-γ, IL-4, IL-12, IL-10) against B. rodhaini or B. microti after challenge infection. Mock mice, however, showed rapid increases of these cytokines, which means disordered cytokines secretion occurred during the acute stage of challenge infection. The above results proved that mice immunized with alive B. rodhaini could acquire protective immunity against B. rodhaini and B. microti infections. PMID:27423972

  9. Exploring the host transcriptome for mechanisms underlying protective immunity and resistance to nematode infections in ruminants.

    PubMed

    Li, Robert W; Choudhary, Ratan K; Capuco, Anthony V; Urban, Joseph F

    2012-11-23

    Nematode infections in ruminants are a major impediment to the profitable production of meat and dairy products, especially for small farms. Gastrointestinal parasitism not only negatively impacts weight gain and milk yield, but is also a major cause of mortality in small ruminants. The current parasite control strategy involves heavy use of anthelmintics that has resulted in the emergence of drug-resistant parasite strains. This, in addition to increasing consumer demand for animal products that are free of drug residues has stimulated development of alternative strategies, including selective breeding of parasite resistant ruminants. The development of protective immunity and manifestations of resistance to nematode infections relies upon the precise expression of the host genome that is often confounded by mechanisms simultaneously required to control multiple nematode species as well as ecto- and protozoan parasites, and microbial and viral pathogens. Understanding the molecular mechanisms underlying these processes represents a key step toward development of effective new parasite control strategies. Recent progress in characterizing the transcriptome of both hosts and parasites, utilizing high-throughput microarrays and RNA-seq technology, has led to the recognition of unique interactions and the identification of genes and biological pathways involved in the response to parasitism. Innovative use of the knowledge gained by these technologies should provide a basis for enhancing innate immunity while limiting the polarization of acquired immunity can negatively affect optimal responses to co-infection. Strategies for parasite control that use diet and vaccine/adjuvant combination could be evaluated by monitoring the host transcriptome for induction of appropriate mechanisms for imparting parasite resistance. Knowledge of different mechanisms of host immunity and the critical regulation of parasite development, physiology, and virulence can also selectively

  10. Intranasal immunization with a formalin-inactivated human influenza A virus whole-virion vaccine alone and intranasal immunization with a split-virion vaccine with mucosal adjuvants show similar levels of cross-protection.

    PubMed

    Okamoto, Shigefumi; Matsuoka, Sumiko; Takenaka, Nobuyuki; Haredy, Ahmad M; Tanimoto, Takeshi; Gomi, Yasuyuki; Ishikawa, Toyokazu; Akagi, Takami; Akashi, Mitsuru; Okuno, Yoshinobu; Mori, Yasuko; Yamanishi, Koichi

    2012-07-01

    The antigenicity of seasonal human influenza virus changes continuously; thus, a cross-protective influenza vaccine design needs to be established. Intranasal immunization with an influenza split-virion (SV) vaccine and a mucosal adjuvant induces cross-protection; however, no mucosal adjuvant has been assessed clinically. Formalin-inactivated intact human and avian viruses alone (without adjuvant) induce cross-protection against the highly pathogenic H5N1 avian influenza virus. However, it is unknown whether seasonal human influenza formalin-inactivated whole-virion (WV) vaccine alone induces cross-protection against strains within a subtype or in a different subtype of human influenza virus. Furthermore, there are few reports comparing the cross-protective efficacy of the WV vaccine and SV vaccine-mucosal adjuvant mixtures. Here, we found that the intranasal human influenza WV vaccine alone induced both the innate immune response and acquired immune response, resulting in cross-protection against drift variants within a subtype of human influenza virus. The cross-protective efficacy conferred by the WV vaccine in intranasally immunized mice was almost the same as that conferred by a mixture of SV vaccine and adjuvants. The level of cross-protective efficacy was correlated with the cross-reactive neutralizing antibody titer in the nasal wash and bronchoalveolar fluids. However, neither the SV vaccine with adjuvant nor the WV vaccine induced cross-reactive virus-specific cytotoxic T-lymphocyte activity. These results suggest that the intranasal human WV vaccine injection alone is effective against variants within a virus subtype, mainly through a humoral immune response, and that the cross-protection elicited by the WV vaccine and the SV vaccine plus mucosal adjuvants is similar.

  11. Lymphatic system: an active pathway for immune protection.

    PubMed

    Liao, Shan; von der Weid, P Y

    2015-02-01

    Lymphatic vessels are well known to participate in the immune response by providing the structural and functional support for the delivery of antigens and antigen presenting cells to draining lymph nodes. Recent advances have improved our understanding of how the lymphatic system works and how it participates to the development of immune responses. New findings suggest that the lymphatic system may control the ultimate immune response through a number of ways which may include guiding antigen/dendritic cells (DC) entry into initial lymphatics at the periphery; promoting antigen/DC trafficking through afferent lymphatic vessels by actively facilitating lymph and cell movement; enabling antigen presentation in lymph nodes via a network of lymphatic endothelial cells and lymph node stroma cell and finally by direct lymphocytes exit from lymph nodes. The same mechanisms are likely also important to maintain peripheral tolerance. In this review we will discuss how the morphology and gene expression profile of the lymphatic endothelial cells in lymphatic vessels and lymph nodes provides a highly efficient pathway to initiate immune responses. The fundamental understanding of how lymphatic system participates in immune regulation will guide the research on lymphatic function in various diseases.

  12. Intracellular replication-deficient Leishmania donovani induces long lasting protective immunity against visceral leishmaniasis.

    PubMed

    Selvapandiyan, Angamuthu; Dey, Ranadhir; Nylen, Susanne; Duncan, Robert; Sacks, David; Nakhasi, Hira L

    2009-08-01

    No vaccine is currently available for visceral leishmaniasis (VL) caused by Leishmania donovani. This study addresses whether a live attenuated centrin gene-deleted L. donovani (LdCen1(-/-)) parasite can persist and be both safe and protective in animals. LdCen1(-/-) has a defect in amastigote replication both in vitro and ex vivo in human macrophages. Safety was shown by the lack of parasites in spleen and liver in susceptible BALB/c mice, immune compromised SCID mice, and human VL model hamsters 10 wk after infection. Mice immunized with LdCen1(-/-) showed early clearance of virulent parasite challenge not seen in mice immunized with heat killed parasites. Upon virulent challenge, the immunized mice displayed in the CD4(+) T cell population a significant increase of single and multiple cytokine (IFN-gamma, IL-2, and TNF) producing cells and IFN-gamma/IL10 ratio. Immunized mice also showed increased IgG2a immunoglobulins and NO production in macrophages. These features indicated a protective Th1-type immune response. The Th1 response correlated with a significantly reduced parasite burden in the spleen and no parasites in the liver compared with naive mice 10 wk post challenge. Protection was observed, when challenged even after 16 wk post immunization, signifying a sustained immunity. Protection by immunization with attenuated parasites was also seen in hamsters. Immunization with LdCen1(-/-) also cross-protected mice against infection with L. braziliensis that causes mucocutaneous leishmaniasis. Results indicate that LdCen1(-/-) can be a safe and effective vaccine candidate against VL as well as mucocutaneous leishmaniasis causing parasites.

  13. Protective immune barrier against hepatitis B is needed in individuals born before infant HBV vaccination program in China.

    PubMed

    Yang, Shigui; Yu, Chengbo; Chen, Ping; Deng, Min; Cao, Qing; Li, Yiping; Ren, Jingjing; Xu, Kaijin; Yao, Jun; Xie, Tiansheng; Wang, Chencheng; Cui, Yuanxia; Ding, Cheng; Tian, Guo; Wang, Bing; Zhang, Xiaoyan; Ruan, Bing; Li, Lanjuan

    2015-01-01

    The hepatitis B prevalence rate in adults is still at a high to intermediate level in China. Our purpose was to explore the incidence rate and protective immune barrier against hepatitis B in adults in China. A sample of 317961 participants was multi-screened for hepatitis B surface antigens (HBsAg) in a large-scale cohort of the National Hepatitis B Demonstration Project. A total of 5401 persons were newly-infected, representing an incidence rate of 0.81 (95% CI: 0.77-0.85) per 100 person-years after adjusted by gender and age. History of acquired immune deficiency syndrome, birth prior to 1992, coastal residence, family history of HBV, and migrant worker status were significantly associated with higher incidence, while HBV vaccination and greater exercise with lower incidence. The hepatitis B surface antibody (HBsAb) positive rate was negatively correlated with the incidence rate of hepatitis B (r = -0.826). Linear fitting yielded an incidence rate of 1.23 plus 0.02 multiplied by HBsAb positive rate. The study firstly identified the HBsAg incidence rate, which was reduced to 0.1 per 100 person-years after vaccination coverage of about 64%. The protective immune barrier against hepatitis B needs to be established in individuals born prior to the advent of infant HBV vaccination. PMID:26655735

  14. Protective immunity by oral immunization with heat-killed Shigella strains in a guinea pig colitis model.

    PubMed

    Barman, Soumik; Koley, Hemanta; Ramamurthy, Thandavarayan; Chakrabarti, Manoj Kumar; Shinoda, Sumio; Nair, Gopinath Balakrish; Takeda, Yoshifumi

    2013-11-01

    The protective efficacy of and immune response to heat-killed cells of monovalent and hexavalent mixtures of six serogroups/serotypes of Shigella strains (Shigella dysenteriae 1, Shigella flexneri 2a, S. flexneri 3a, S. flexneri 6, Shigella boydii 4, and Shigella sonnei) were examined in a guinea pig colitis model. A monovalent or hexavalent mixture containing 1 × 10(7) of each serogroup/serotype of heat-killed Shigella cells was administered orally on Days 0, 7, 14 and 21. On Day 28, the immunized animals were challenged rectally with 1 × 10(9) live virulent cells of each of the six Shigella serogroups/serotypes. In all immunized groups, significant levels of protection were observed after these challenges. The serum titers of IgG and IgA against the lipopolysaccharide of each of the six Shigella serogroups/serotypes increased exponential during the course of immunization. High IgA titers against the lipopolysaccharide of each of the six Shigella serogroups/serotypes were also observed in intestinal lavage fluid from all immunized animals. These data indicate that a hexavalent mixture of heat-killed cells of the six Shigella serogroups/serotypes studied would be a possible broad-spectrum candidate vaccine against shigellosis.

  15. The role of nurses in the human immunodeficiency virus/acquired immune deficiency syndrome policy process in Botswana.

    PubMed

    Phaladze, N A

    2003-03-01

    In Botswana, there is dearth of literature on the role of nursing in health-care policy and resource allocation and yet nurses constitute the majority (85%) of health manpower. The health-care delivery system depends mostly on nurses for service provision. There were two main purposes of this study: first, to gather descriptive data from major key players (with particular emphasis on nurses) concerning knowledge of the policy process and resource allocation for management and care of clients with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) in Botswana; and, second, to identify nurse characteristics (e.g. position, education, experience, job category) associated with motivation to influence health-care policy in HIV/AIDS management and care in Botswana. A policy process conceptual framework was used to guide data collection and analysis. A case-study research method was used to conduct in-depth interviews from a purposive sample of 19 policy makers, and a survey questionnaire was used to collect data from a purposive sample of 95 registered nurses from six study sites in Botswana. The study findings indicate minimal participation of nurses in health-care policy process and resource allocation. The demographic variable of position was a predictor of the involvement of nurses in policy and in budgetary decisions. Both survey and interview data indicated that this minimal participation of nurses in the policy process resulted in implementation problems, thus compromising service provision. Implications of the findings for the nursing profession, nursing practice and policy, which address the importance of nurses' involvement, are discussed. PMID:12581124

  16. Development and Evaluation of a Complementary and Alternative Medicine Use Survey in African-Americans with Acquired Immune Deficiency Syndrome

    PubMed Central

    Sterk, Claire; McCarty, Frances; Hankerson-Dyson, Dana; DiClemente, Ralph

    2010-01-01

    Abstract Objectives The purpose of the current study was to develop and evaluate the psychometric properties of a culturally- and stage-of-disease-appropriate measure of complementary and alternative medicine (CAM) use among a population of African-American individuals with acquired immune deficiency syndrome (AIDS) using a mixed-method design. Design Data were collected in two phases. In phase 1, qualitative data were used to refine an existing CAM measure for the specific study population in the present study. In phase 2, this refined instrument was implemented in a larger sample. The resulting numeric data were analyzed to evaluate the psychometric properties of the revised CAM instrument. Setting Data were collected from patients who were receiving care from the infectious disease clinic of a large, public, urban hospital in the Southeastern United States. Subjects Patients were eligible to participate if they (1) were receiving their care from the clinic, (2) had an AIDS diagnosis, (3) were identified as African-American, (4) were ≥21 years of age, (5) spoke English, and (6) were not cognitively impaired. Measures Focus groups in phase 1 were conducted with a semistructured focus group guide. Participants also completed a basic sociodemographic survey. Phase 2 participants used programmed laptops to answer questions about their CAM use and several sociodemographic questions. Results Information from the focus groups prompted some substantive revisions in the already-existing CAM survey. The revised instrument had satisfactory face validity and adequate test–retest reliability (r = 0.79). Furthermore, the instrument factored in a manner that was interpretable and consistent with prior findings. Conclusions In order for human immunodeficiency virus health care providers to provide the best care to their patients, they need to be informed about the types and frequency of CAM use among their patients. This can be accomplished by methodologically developing

  17. Orchitis and human immunodeficiency virus type 1 infected cells in reproductive tissues from men with the acquired immune deficiency syndrome.

    PubMed Central

    Pudney, J.; Anderson, D.

    1991-01-01

    Mechanisms underlying human immunodeficiency virus type 1 (HIV-1) infection of the male reproductive tract and the sexual transmission of HIV-1 through semen are poorly understood. To address these issues, the authors performed morphologic and immunocytochemical analyses of reproductive tissues obtained at autopsy from 43 male acquired immune deficiency syndrome (AIDS) patients. Monoclonal antibodies recognizing different subpopulations of white blood cells were used to detect leukocyte infiltration and map the location of potential lymphocytic/monocytic HIV-1 host cells and immunocytochemistry and in situ hybridization techniques were used to detect HIV-1-infected cells in the testis, excurrent ducts, and prostate. Distinct pathologic changes were observed in a majority of testes of AIDS patients that included azoospermia, hyalinization of the boundary wall of seminiferous tubules, and lymphocytic infiltration of the interstitium. The reproductive excurrent ducts and prostate appeared morphologically normal except for the presence of focal accumulations of white blood cells in the connective tissue stroma. In the testis many white blood cells were shown to be CD4+, indicating the presence of abundant host cells (T-helper/inducer lymphocytes and macrophages) for HIV-1. Furthermore macrophages and cells of lymphocytic morphology were observed migrating across the boundary walls of hyalinized seminiferous in tubules to enter the lumen. In 9 of the 23 cases tested for HIV-1 protein expression by immunocytochemistry. HIV-1 + cells of lymphocytic/monocytic morphology were found in the seminiferous tubules and interstitium of the testis, epididymal epithelium, and connective tissue of the epididymis and prostate. One patient with epididymal blockage had accumulations of HIV-1-antigen-positive cells of macrophages morphology in the distended lumen of the efferent ducts. There was no evidence of active HIV-1 infection in germ cells or Sertoli cells of the seminiferous

  18. Strain-Specific Protective Effect of the Immunity Induced by Live Malarial Sporozoites under Chloroquine Cover

    PubMed Central

    Wijayalath, Wathsala; Cheesman, Sandra; Tanabe, Kazuyuki; Handunnetti, Shiroma; Carter, Richard; Pathirana, Sisira

    2012-01-01

    The efficacy of a whole-sporozoite malaria vaccine would partly be determined by the strain-specificity of the protective responses against malarial sporozoites and liver-stage parasites. Evidence from previous reports were inconsistent, where some studies have shown that the protective immunity induced by irradiated or live sporozoites in rodents or humans were cross-protective and in others strain-specific. In the present work, we have studied the strain-specificity of live sporozoite-induced immunity using two genetically and immunologically different strains of Plasmodium cynomolgi, Pc746 and PcCeylon, in toque monkeys. Two groups of monkeys were immunized against live sporozoites of either the Pc746 (n = 5), or the PcCeylon (n = 4) strain, by the bites of 2–4 sporozoite-infected Anopheles tessellates mosquitoes per monkey under concurrent treatments with chloroquine and primaquine to abrogate detectable blood infections. Subsequently, a group of non-immunized monkeys (n = 4), and the two groups of immunized monkeys were challenged with a mixture of sporozoites of the two strains by the bites of 2–5 infective mosquitoes from each strain per monkey. In order to determine the strain-specificity of the protective immunity, the proportions of parasites of the two strains in the challenge infections were quantified using an allele quantification assay, Pyrosequencing™, based on a single nucleotide polymorphism (SNP) in the parasites’ circumsporozoite protein gene. The Pyrosequencing™ data showed that a significant reduction of parasites of the immunizing strain in each group of strain-specifically immunized monkeys had occurred, indicating a stronger killing effect on parasites of the immunizing strain. Thus, the protective immunity developed following a single, live sporozoite/chloroquine immunization, acted specifically against the immunizing strain and was, therefore, strain-specific. As our experiment does not allow us to determine the

  19. Protective immunity against Naegleria fowleri infection on mice immunized with the rNfa1 protein using mucosal adjuvants.

    PubMed

    Lee, Jinyoung; Yoo, Jong-Kyun; Sohn, Hae-Jin; Kang, Hee-kyoung; Kim, Daesik; Shin, Ho-Joon; Kim, Jong-Hyun

    2015-04-01

    The free-living amoeba, Naegleria fowleri, causes a fatal disease called primary amoebic meningoencephalitis (PAM) in humans and experimental animals. Of the pathogenic mechanism of N. fowleri concerning host tissue invasion, the adherence of amoeba to hose cells is the most important. We previously cloned the nfa1 gene from N. fowleri. The protein displayed immunolocalization in the pseudopodia, especially the food-cups structure, and was related to the contact-dependent mechanism of the amoebic pathogenicity in N. fowleri infection. The cholera toxin B subunit (CTB) and Escherichia coli heat-labile enterotoxin B subunit (LTB) have been used as potent mucosal adjuvants via the parenteral route of immunization in most cases. In this study, to examine the effect of protective immunity of the Nfa1 protein for N. fowleri infection with enhancement by CTB or LTB adjuvants, intranasally immunized BALB/c mice were infected with N. fowleri trophozoites for the development of PAM. The mean time to death of mice immunized with the Nfa1 protein using LTB or CTB adjuvant was prolonged by 5 or 8 days in comparison with that of the control mice. In particular, the survival rate of mice immunized with Nfa1 plus CTB was 100% during the experimental period. The serum IgG levels were significantly increased in mice immunized with Nfa1 protein plus CTB or LTB adjuvants. These results suggest that the Nfa1 protein, with CTB or LTB adjuvants, induces strong protective immunity in mice with PAM due to N. fowleri infection. PMID:25604672

  20. Protective immunity against Naegleria fowleri infection on mice immunized with the rNfa1 protein using mucosal adjuvants.

    PubMed

    Lee, Jinyoung; Yoo, Jong-Kyun; Sohn, Hae-Jin; Kang, Hee-kyoung; Kim, Daesik; Shin, Ho-Joon; Kim, Jong-Hyun

    2015-04-01

    The free-living amoeba, Naegleria fowleri, causes a fatal disease called primary amoebic meningoencephalitis (PAM) in humans and experimental animals. Of the pathogenic mechanism of N. fowleri concerning host tissue invasion, the adherence of amoeba to hose cells is the most important. We previously cloned the nfa1 gene from N. fowleri. The protein displayed immunolocalization in the pseudopodia, especially the food-cups structure, and was related to the contact-dependent mechanism of the amoebic pathogenicity in N. fowleri infection. The cholera toxin B subunit (CTB) and Escherichia coli heat-labile enterotoxin B subunit (LTB) have been used as potent mucosal adjuvants via the parenteral route of immunization in most cases. In this study, to examine the effect of protective immunity of the Nfa1 protein for N. fowleri infection with enhancement by CTB or LTB adjuvants, intranasally immunized BALB/c mice were infected with N. fowleri trophozoites for the development of PAM. The mean time to death of mice immunized with the Nfa1 protein using LTB or CTB adjuvant was prolonged by 5 or 8 days in comparison with that of the control mice. In particular, the survival rate of mice immunized with Nfa1 plus CTB was 100% during the experimental period. The serum IgG levels were significantly increased in mice immunized with Nfa1 protein plus CTB or LTB adjuvants. These results suggest that the Nfa1 protein, with CTB or LTB adjuvants, induces strong protective immunity in mice with PAM due to N. fowleri infection.

  1. Protection of gerbils from amebic liver abscess by immunization with a recombinant Entamoeba histolytica antigen.

    PubMed Central

    Zhang, T; Cieslak, P R; Stanley, S L

    1994-01-01

    Amebiasis, infection by the intestinal protozoan parasite Entamoeba histolytica, is a leading parasitic cause of death. As a step in the development of a recombinant antigen vaccine to prevent E. histolytica infection, we looked at the ability of a recombinant version of the serine-rich E. histolytica protein (SREHP) to elicit a protective immune response against invasive amebic disease. Gerbils, a standard model for amebic liver abscess, were immunized with either a recombinant SREHP/maltose-binding protein (MBP) fusion, recombinant MBP alone, or phosphate-buffered saline (PBS), all combined with complete Freund's adjuvant. In the first trial (group 1), gerbils received a primary and two booster immunizations intraperitoneally; in the second trial (group 2), gerbils were immunized by a single intradermal injection. SREHP/MBP-immunized gerbils in both groups produced antibody to native SHEHP and developed delayed-type hypersensitivity responses to recombinant SREHP. All gerbils were challenged by an intrahepatic injection with 5 x 10(4) virulent E. histolytica HM1-IMSS trophozoites. Complete protection from amebic liver abscess was seen in 64% of the SHEHP/MBP-immunized gerbils in group 1 and in 100% of the SREHP/MBP-immunized gerbils in group 2. There was no protection observed in MBP- or PBS-immunized gerbils in either group. Our results indicate that the SREHP molecule has potential as a vaccine to prevent amebic infection and demonstrate that successful vaccination of animals with recombinant E. histolytica antigen vaccines is possible. Images PMID:8132322

  2. "Immunization mobile" brings protection to children in southeastern Idaho.

    PubMed Central

    Stanger, L

    1987-01-01

    The problem that needs to be addressed is the 58 percent immunity level among 2-year-olds in southeastern Idaho, a level created by the indifference or fear of parents. Southeastern Idaho has the highest birth rate of any region in the State, and this situation has created a large group of children susceptible to vaccine-preventable diseases. The mobile unit, which consists of a specially equipped motor home, allows easy access to immunizations for groups of children and their parents. A search of the computerized record system installed in the mobile unit can provide data on past immunizations for each registered child. The target audience for the mobile unit's visits is church groups because of the particular cultural demographics of this region. In 1987, the District Seven Health Department, a State- and county-funded agency, expects to increase the number of doses of vaccine given by 3,000 over the 19,953 given in 1986. The "Shots for Tots" program is unique in the State of Idaho. Its expansion may be anticipated as the unit becomes better known in the region. The alternative to using aggressive, innovative techniques to motivate people to become immunized is disease. Images p545-a PMID:3116586

  3. An active immunization approach to generate protective catalytic antibodies.

    PubMed Central

    Wang, J; Han, Y; Wilkinson, M F

    2001-01-01

    We report that mice immunized with a phosphate immunogen produced polyclonal catalytic antibodies (PCAbs) that catalysed the hydrolysis of carbaryl, a widely used broad-spectrum carbamate insecticide that exerts toxic effects in animals and humans. The reaction catalysed by the PCAbs (IgGs) obeyed Michaelis-Menten kinetics in vitro with the following values at pH 8.0 and 25 degrees C: K(m) approximately 8.0 microM, k(cat)=4.8x10(-3)-5.8x10(-1), k(cat)/k(non-cat)=5.6x10(1)-6.8x10(3) (where k(non-cat) is the rate constant of the reaction in the absence of added catalyst). The PCAbs were also active in whole sera under physiological conditions in vitro. The PCAbs induced in vivo were also active in vivo, as immunization with the phosphate immunogen decreased the mouse blood concentration of carbaryl. To our knowledge, this is the first report demonstrating that active immunization generates antibodies possessing therapeutic catalytic function in vivo. We propose that active immunization schemes that induce enzymically active antibodies may provide a highly specific therapeutic approach for degrading toxic substances. PMID:11696002

  4. No more kidding around: restructuring non-medical childhood immunization exemptions to ensure public health protection.

    PubMed

    Silverman, Ross D

    2003-01-01

    Professor Silverman's article examines the complex challenges faced by U.S. policymakers attempting to balance the public health protections of mandatory childhood immunization programs with the legal, religious, philosophical, and practical concerns raised by permitting non-medical exemptions under the programs. The article begins with a discussion of the history of childhood immunization programs, and continues by describing the inconsistency of enforcement of state immunization laws and exemptions. The author analyzes recent cases from New York, Wyoming, and Arkansas, and discusses how these decisions both pose threats to these programs' public health protections, while also offering insight into potential problems for other state vaccination programs. Professor Silverman concludes by advocating that states adopt an "informed refusal" approach to vaccination exemption as a way of improving immunity protections, while respecting the autonomy rights of those who wish to opt out of the program.

  5. The association between naturally acquired IgG subclass specific antibodies to the PfRH5 invasion complex and protection from Plasmodium falciparum malaria.

    PubMed

    Weaver, Rupert; Reiling, Linda; Feng, Gaoqian; Drew, Damien R; Mueller, Ivo; Siba, Peter M; Tsuboi, Takafumi; Richards, Jack S; Fowkes, Freya J I; Beeson, James G

    2016-01-01

    Understanding the targets and mechanisms of human immunity to malaria is important for advancing the development of highly efficacious vaccines and serological tools for malaria surveillance. The PfRH5 and PfRipr proteins form a complex on the surface of P. falciparum merozoites that is essential for invasion of erythrocytes and are vaccine candidates. We determined IgG subclass responses to these proteins among malaria-exposed individuals in Papua New Guinea and their association with protection from malaria in a longitudinal cohort of children. Cytophilic subclasses, IgG1 and IgG3, were predominant with limited IgG2 and IgG4, and IgG subclass-specific responses were higher in older children and those with active infection. High IgG3 to PfRH5 and PfRipr were significantly and strongly associated with reduced risk of malaria after adjusting for potential confounding factors, whereas associations for IgG1 responses were generally weaker and not statistically significant. Results further indicated that malaria exposure leads to the co-acquisition of IgG1 and IgG3 to PfRH5 and PfRipr, as well as to other PfRH invasion ligands, PfRH2 and PfRH4. These findings suggest that IgG3 responses to PfRH5 and PfRipr may play a significant role in mediating naturally-acquired immunity and support their potential as vaccine candidates and their use as antibody biomarkers of immunity. PMID:27604417

  6. The association between naturally acquired IgG subclass specific antibodies to the PfRH5 invasion complex and protection from Plasmodium falciparum malaria

    PubMed Central

    Weaver, Rupert; Reiling, Linda; Feng, Gaoqian; Drew, Damien R.; Mueller, Ivo; Siba, Peter M.; Tsuboi, Takafumi; Richards, Jack S.; Fowkes, Freya J. I.; Beeson, James G.

    2016-01-01

    Understanding the targets and mechanisms of human immunity to malaria is important for advancing the development of highly efficacious vaccines and serological tools for malaria surveillance. The PfRH5 and PfRipr proteins form a complex on the surface of P. falciparum merozoites that is essential for invasion of erythrocytes and are vaccine candidates. We determined IgG subclass responses to these proteins among malaria-exposed individuals in Papua New Guinea and their association with protection from malaria in a longitudinal cohort of children. Cytophilic subclasses, IgG1 and IgG3, were predominant with limited IgG2 and IgG4, and IgG subclass-specific responses were higher in older children and those with active infection. High IgG3 to PfRH5 and PfRipr were significantly and strongly associated with reduced risk of malaria after adjusting for potential confounding factors, whereas associations for IgG1 responses were generally weaker and not statistically significant. Results further indicated that malaria exposure leads to the co-acquisition of IgG1 and IgG3 to PfRH5 and PfRipr, as well as to other PfRH invasion ligands, PfRH2 and PfRH4. These findings suggest that IgG3 responses to PfRH5 and PfRipr may play a significant role in mediating naturally-acquired immunity and support their potential as vaccine candidates and their use as antibody biomarkers of immunity. PMID:27604417

  7. Trimming Surface Sugars Protects Histoplasma from Immune Attack.

    PubMed

    Brown, Gordon D

    2016-01-01

    Dectin-1 is an essential innate immune receptor that recognizes β-glucans in fungal cell walls. Its importance is underscored by the mechanisms that fungal pathogens have evolved to avoid detection by this receptor. One such pathogen is Histoplasma capsulatum, and in a recent article in mBio, Rappleye's group presented data showing that yeasts of this organism secrete a β-glucanase, Eng1, which acts to prune β-glucans that are exposed on the fungal cell surface [A. L. Garfoot et al., mBio 7(2):e01388-15, 2016, http://dx.doi.org/10.1128/mBio.01388-15]. The trimming of these sugars reduces immune recognition through Dectin-1 and subsequent inflammatory responses, enhancing the pathogenesis of H. capsulatum. PMID:27118584

  8. Protective immunity to Naegleria fowleri in experimental amebic meningoencephalitis.

    PubMed

    Thong, Y H; Shepherd, C; Ferrante, A; Rowan-Kelly, B

    1978-03-01

    Naegleria fowleri, a free-living ameboflagellate, is the causative organism of primary amebic meningoencephalitis. Intranasal inoculation of N. fowleri in mice produces an infection similar to human disease. Mice immunized with live N. fowleri by intraperitoneal injection were found to be more resistant to subsequent intranasal challenge. These results may provide a lead to the development of immunotherapy for this virulent disease for which satisfactory chemotherapy is presently unavailable. PMID:646016

  9. Protective Immunity against Eimeria acervulina following In Ovo Immunization with a Recombinant Subunit Vaccine and Cytokine Genes

    PubMed Central

    Ding, Xicheng; Lillehoj, Hyun S.; Quiroz, Marco A.; Bevensee, Erich; Lillehoj, Erik P.

    2004-01-01

    A purified recombinant protein from Eimeria acervulina (3-1E) was used to vaccinate chickens in ovo against coccidiosis both alone and in combination with expression plasmids encoding the interleukin 1 (IL-1), IL-2, IL-6, IL-8, IL-15, IL-16, IL-17, IL-18, or gamma interferon (IFN-γ) gene. When used alone, vaccination with 100 or 500 μg of 3-1E resulted in significantly decreased oocyst shedding compared with that in nonvaccinated chickens. Simultaneous vaccination of the 3-1E protein with the IL-1, -15, -16, or -17 gene induced higher serum antibody responses than 3-1E alone. To evaluate protective intestinal immunity, vaccinated birds were challenged with live E. acervulina oocysts 14 days posthatch, and fecal-oocyst shedding and body weight gain were determined as parameters of coccidiosis. Chickens vaccinated with 3-1E protein showed significantly lower oocyst shedding and normal body weight gain than nonvaccinated and infected controls. Simultaneous immunization with 3-1E and the IL-2, -15, -17, or -18 or IFN-γ gene further reduced oocyst shedding compared with that achieved with 3-1E alone. These results provide the first evidence that in ovo vaccination with the recombinant 3-1E Eimeria protein induces protective intestinal immunity against coccidiosis, and this effect was enhanced by coadministration of genes encoding immunity-related cytokines. PMID:15557615

  10. Intranasal DNA vaccination induces potent mucosal and systemic immune responses and cross-protective immunity against influenza viruses.

    PubMed

    Torrieri-Dramard, Lea; Lambrecht, Bénédicte; Ferreira, Helena Lage; Van den Berg, Thierry; Klatzmann, David; Bellier, Bertrand

    2011-03-01

    The induction of potent virus-specific immune responses at mucosal surfaces where virus transmission occurs is a major challenge for vaccination strategies. In the case of influenza vaccination, this has been achieved only by intranasal delivery of live-attenuated vaccines that otherwise pose safety problems. Here, we demonstrate that potent mucosal and systemic immune responses, both cellular and humoral, are induced by intranasal immunization using formulated DNA. We show that formulation with the DNA carrier polyethylenimine (PEI) improved by a 1,000-fold the efficiency of gene transfer in the respiratory track following intranasal administration of luciferase-coding DNA. Using PEI formulation, intranasal vaccination with DNA-encoding hemagglutinin (HA) from influenza A H5N1 or (H1N1)2009 viruses induced high levels of HA-specific immunoglobulin A (IgA) antibodies that were detected in bronchoalveolar lavages (BALs) and the serum. No mucosal responses could be detected after parenteral or intranasal immunization with naked-DNA. Furthermore, intranasal DNA vaccination with HA from a given H5N1 virus elicited full protection against the parental strain and partial cross-protection against a distinct highly pathogenic H5N1 strain that could be improved by adding neuraminidase (NA) DNA plasmids. Our observations warrant further investigation of intranasal DNA as an effective vaccination route.

  11. Sublingual Vaccination Induces Mucosal and Systemic Adaptive Immunity for Protection against Lung Tumor Challenge

    PubMed Central

    Singh, Shailbala; Yang, Guojun; Schluns, Kimberly S.; Anthony, Scott M.; Sastry, K. Jagannadha

    2014-01-01

    Sublingual route offers a safer and more practical approach for delivering vaccines relative to other systemic and mucosal immunization strategies. Here we present evidence demonstrating protection against ovalbumin expressing B16 (B16-OVA) metastatic melanoma lung tumor formation by sublingual vaccination with the model tumor antigen OVA plus synthetic glycolipid alpha-galactosylceramide (aGalCer) for harnessing the adjuvant potential of natural killer T (NKT) cells, which effectively bridge innate and adaptive arms of the immune system. The protective efficacy of immunization with OVA plus aGalCer was antigen-specific as immunized mice challenged with parental B16 tumors lacking OVA expression were not protected. Multiple sublingual immunizations in the presence, but not in the absence of aGalCer, resulted in repeated activation of NKT cells in the draining lymph nodes, spleens, and lungs of immunized animals concurrent with progressively increasing OVA-specific CD8+ T cell responses as well as serum IgG and vaginal IgA levels. Furthermore, sublingual administration of the antigen only in the presence of the aGalCer adjuvant effectively boosted the OVA-specific immune responses. These results support potential clinical utility of sublingual route of vaccination with aGalCer-for prevention of pulmonary metastases. PMID:24599269

  12. [Comment on the intervention of Traditional Chinese Medicine on survival rates of patients living with human immunodeficiency virus and acquired immune deficiency syndrome].

    PubMed

    Li, Qiang; Liu, Zhibin; Yang, Jiping; Guo, Huijun; Xu, Liran

    2016-06-01

    Despite many differences between Traditional Chinese Medicine (TCM) and conventional medicine, the use of TCM in the treatment of human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) is increasingly recognized and accepted by patients. Recent research findings on the benefits of Chinese herbal medicine on long-term survival in patients with HIV/AIDS are encouraging and hopeful, but inconclusive. More research is needed.

  13. Unexpected role for IL-17 in protective immunity against hypervirulent Mycobacterium tuberculosis HN878 infection.

    PubMed

    Gopal, Radha; Monin, Leticia; Slight, Samantha; Uche, Uzodinma; Blanchard, Emmeline; Fallert Junecko, Beth A; Ramos-Payan, Rosalio; Stallings, Christina L; Reinhart, Todd A; Kolls, Jay K; Kaushal, Deepak; Nagarajan, Uma; Rangel-Moreno, Javier; Khader, Shabaana A

    2014-05-01

    Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), infects one third of the world's population. Among these infections, clinical isolates belonging to the W-Beijing appear to be emerging, representing about 50% of Mtb isolates in East Asia, and about 13% of all Mtb isolates worldwide. In animal models, infection with W-Beijing strain, Mtb HN878, is considered "hypervirulent" as it results in increased mortality and causes exacerbated immunopathology in infected animals. We had previously shown the Interleukin (IL) -17 pathway is dispensable for primary immunity against infection with the lab adapted Mtb H37Rv strain. However, it is not known whether IL-17 has any role to play in protective immunity against infection with clinical Mtb isolates. We report here that lab adapted Mtb strains, such as H37Rv, or less virulent Mtb clinical isolates, such as Mtb CDC1551, do not require IL-17 for protective immunity against infection while infection with Mtb HN878 requires IL-17 for early protective immunity. Unexpectedly, Mtb HN878 induces robust production of IL-1β through a TLR-2-dependent mechanism, which supports potent IL-17 responses. We also show that the role for IL-17 in mediating protective immunity against Mtb HN878 is through IL-17 Receptor signaling in non-hematopoietic cells, mediating the induction of the chemokine, CXCL-13, which is required for localization of T cells within lung lymphoid follicles. Correct T cell localization within lymphoid follicles in the lung is required for maximal macrophage activation and Mtb control. Since IL-17 has a critical role in vaccine-induced immunity against TB, our results have far reaching implications for the design of vaccines and therapies to prevent and treat emerging Mtb strains. In addition, our data changes the existing paradigm that IL-17 is dispensable for primary immunity against Mtb infection, and instead suggests a differential role for IL-17 in early protective immunity against

  14. Unexpected Role for IL-17 in Protective Immunity against Hypervirulent Mycobacterium tuberculosis HN878 Infection

    PubMed Central

    Gopal, Radha; Monin, Leticia; Slight, Samantha; Uche, Uzodinma; Blanchard, Emmeline; A. Fallert Junecko, Beth; Ramos-Payan, Rosalio; Stallings, Christina L.; Reinhart, Todd A.; Kolls, Jay K.; Kaushal, Deepak; Nagarajan, Uma; Rangel-Moreno, Javier; Khader, Shabaana A.

    2014-01-01

    Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), infects one third of the world's population. Among these infections, clinical isolates belonging to the W-Beijing appear to be emerging, representing about 50% of Mtb isolates in East Asia, and about 13% of all Mtb isolates worldwide. In animal models, infection with W-Beijing strain, Mtb HN878, is considered “hypervirulent” as it results in increased mortality and causes exacerbated immunopathology in infected animals. We had previously shown the Interleukin (IL) -17 pathway is dispensable for primary immunity against infection with the lab adapted Mtb H37Rv strain. However, it is not known whether IL-17 has any role to play in protective immunity against infection with clinical Mtb isolates. We report here that lab adapted Mtb strains, such as H37Rv, or less virulent Mtb clinical isolates, such as Mtb CDC1551, do not require IL-17 for protective immunity against infection while infection with Mtb HN878 requires IL-17 for early protective immunity. Unexpectedly, Mtb HN878 induces robust production of IL-1β through a TLR-2-dependent mechanism, which supports potent IL-17 responses. We also show that the role for IL-17 in mediating protective immunity against Mtb HN878 is through IL-17 Receptor signaling in non-hematopoietic cells, mediating the induction of the chemokine, CXCL-13, which is required for localization of T cells within lung lymphoid follicles. Correct T cell localization within lymphoid follicles in the lung is required for maximal macrophage activation and Mtb control. Since IL-17 has a critical role in vaccine-induced immunity against TB, our results have far reaching implications for the design of vaccines and therapies to prevent and treat emerging Mtb strains. In addition, our data changes the existing paradigm that IL-17 is dispensable for primary immunity against Mtb infection, and instead suggests a differential role for IL-17 in early protective immunity against

  15. Deletion of Parasite Immune Modulatory Sequences Combined with Immune Activating Signals Enhances Vaccine Mediated Protection against Filarial Nematodes

    PubMed Central

    Babayan, Simon A.; Luo, HongLin; Gray, Nick; Taylor, David W.; Allen, Judith E.

    2012-01-01

    Background Filarial nematodes are tissue-dwelling parasites that can be killed by Th2-driven immune effectors, but that have evolved to withstand immune attack and establish chronic infections by suppressing host immunity. As a consequence, the efficacy of a vaccine against filariasis may depend on its capacity to counter parasite-driven immunomodulation. Methodology and Principal Findings We immunised mice with DNA plasmids expressing functionally-inactivated forms of two immunomodulatory molecules expressed by the filarial parasite Litomosoides sigmodontis: the abundant larval transcript-1 (LsALT) and cysteine protease inhibitor-2 (LsCPI). The mutant proteins enhanced antibody and cytokine responses to live parasite challenge, and led to more leukocyte recruitment to the site of infection than their native forms. The immune response was further enhanced when the antigens were targeted to dendritic cells using a single chain Fv-αDEC205 antibody and co-administered with plasmids that enhance T helper 2 immunity (IL-4) and antigen-presenting cell recruitment (Flt3L, MIP-1α). Mice immunised simultaneously against the mutated forms of LsALT and LsCPI eliminated adult parasites faster and consistently reduced peripheral microfilaraemia. A multifactorial analysis of the immune response revealed that protection was strongly correlated with the production of parasite-specific IgG1 and with the numbers of leukocytes present at the site of infection. Conclusions We have developed a successful strategy for DNA vaccination against a nematode infection that specifically targets parasite-driven immunosuppression while simultaneously enhancing Th2 immune responses and parasite antigen presentation by dendritic cells. PMID:23301106

  16. Cross Protective Mucosal Immunity Mediated by Memory Th17 Cells against Streptococcus pneumoniae Lung Infection

    PubMed Central

    Wang, Yan; Jiang, Bin; Guo, Yongli; Li, Wenchao; Tian, Ying; Sonnenberg, Gregory F; Weiser, Jeffery N.; Ni, Xin; Shen, Hao

    2016-01-01

    Pneumonia caused by Streptococcus pneumoniae (Sp) remains a leading cause of serious illness and death worldwide. Immunization with conjugated pneumococcal vaccine has lowered the colonization rate and consequently invasive diseases by inducing serotype-specific antibodies. However, many of current pneumonia cases result from infection by serotype strains not included in the vaccine. In this study, we asked if cross-protection against lung infection by heterologous strains can be induced and investigated the underlying immune mechanism. We found that immune mice recovered from a prior infection were protected against heterologous Sp strains in the pneumonia challenge model, as evident by accelerated bacterial clearance, reduced pathology and apoptosis of lung epithelial cells. Sp infection in the lung induced strong Th17 responses at the lung mucosal site. Transfer of CD4+ T cells from immune mice provided heterologous protection against pneumonia, and this protection was abrogated by IL-17A blockade. Transfer of memory CD4+ T cells from IL-17A knockout mice failed to provide protection. These results indicate that memory Th17 cells played a key role in providing protection against pneumonia in a serotype independent manner and suggest the feasibility of developing a broadly protective vaccine against bacterial pneumonia by targeting mucosal Th17 T cells. PMID:27118490

  17. Vaccination with Legionella pneumophila membranes induces cell-mediated and protective immunity in a guinea pig model of Legionnaires' disease. Protective immunity independent of the major secretory protein of Legionella pneumophila.

    PubMed Central

    Blander, S J; Horwitz, M A

    1991-01-01

    We have examined the capacity of Legionella pneumophila membranes to induce cell-mediated immune responses and protective immunity in a guinea pig model of Legionnaires' disease. Guinea pigs immunized by aerosol with L. pneumophila membranes developed strong cell-mediated immune responses to L. pneumophila membranes as demonstrated by cutaneous delayed-type hypersensitivity and in vitro splenic lymphocyte proliferation. Guinea pigs immunized by aerosol or by subcutaneous inoculation with L. pneumophila membranes developed strong protective immunity against lethal aerosol challenge with L. pneumophila. Overall, in six independent experiments, 39 of 49 (80%) guinea pigs immunized with L. pneumophila membranes survived challenge compared with 2 of 40 (5%) sham-immunized controls (P = 2 x 10(-13). In contrast, guinea pigs immunized by aerosol with formalin-killed L. pneumophila did not develop either a strong cell-mediated immune response to L. pneumophila antigens or protective immunity to lethal aerosol challenge. The capacity of L. pneumophila membranes to induce protective immunity was independent of the major secretory protein of L. pneumophila, which we previously demonstrated is an immunoprotective molecule. Purified L. pneumophila membranes did not contain detectable major secretory protein (MSP) on immunoblots; immunization of guinea pigs with L. pneumophila membranes did not induce anti-MSP antibody; and guinea pigs developed comparable protective immunity after immunization with membranes from either an L. pneumophila strain that secretes the major secretory protein or an isogenic mutant that does not. This study demonstrates that (a) immunization with L. pneumophila membranes but not formalin-killed L. pneumophila induces strong cell-mediated immune responses and protective immunity, (b) L. pneumophila membranes contain immunoprotective molecules distinct from the major secretory protein of L. pneumophila, and (c) L. pneumophila membranes have potential as

  18. Induction of protective immunity against Chlamydia muridarum intracervical infection in DBA/1j mice.

    PubMed

    Tang, Lingli; Yang, Zhangsheng; Zhang, Hongbo; Zhou, Zhiguang; Arulanandam, Bernard; Baseman, Joel; Zhong, Guangming

    2014-03-10

    We previously reported that intracervical inoculation with Chlamydia muridarum induced hydrosalpinx in DBA/1j mice, but intravaginal inoculation failed to do so. In the current study, we found unexpectedly that intrabursal inoculation of live chlamydial organisms via the oviduct failed to induce significant hydrosalpinx. We further tested whether primary infection via intravaginal or intrabursal inoculation could induce protective immunity against hydrosalpinx following intracervical challenge infection. Mice infected intravaginally with C. muridarum were fully protected from developing hydrosalpinx, while intrabursal inoculation offered partial protection. We then compared immune responses induced by the two genital tract inoculations. Both inoculations induced high IFNγ and IL-17 T cell responses although the ratio of IgG2a versus IgG1 in intravaginally infected mice was significantly higher than in mice infected intrabursally. When the antigen-specificities of antibody responses were compared, both groups of mice dominantly recognized 24 C. muridarum antigens, while each group preferentially recognized unique sets of antigens. Thus, we have demonstrated that intrabursal inoculation is neither effective for causing hydrosalpinx nor efficient in inducing protective immunity in DBA/1j mice. Intravaginal immunization, in combination with intracervical challenge infection in DBA/1j mice, can be a useful model for understanding mechanisms of chlamydial pathogenicity and protective immunity.

  19. Basophils help establish protective immunity induced by irradiated larval vaccination for filariasis.

    PubMed

    Torrero, Marina N; Morris, C Paul; Mitre, Blima K; Hübner, Marc P; Fox, Ellen M; Karasuyama, Hajime; Mitre, Edward

    2013-08-12

    Basophils are increasingly recognized as playing important roles in the immune response toward helminths. In this study, we evaluated the role of basophils in vaccine-mediated protection against filariae, tissue-invasive parasitic nematodes responsible for diseases such as elephantiasis and river blindness. Protective immunity and immunological responses were assessed in BALB/c mice vaccinated with irradiated L3 stage larvae and depleted of basophils with weekly injections of anti-CD200R3 antibody. Depletion of basophils after administration of the vaccination regimen but before challenge infection did not alter protective immunity. In contrast, basophil depletion initiated prior to vaccination and continued after challenge infection significantly attenuated the protective effect conferred by vaccination. Vaccine-induced cellular immune responses to parasite antigen were substantially decreased in basophil-depleted mice, with significant decreases in CD4(+) T-cell production of IL-4, IL-5, IL-10, and IFN-γ. Interestingly, skin mast cell numbers, which increased significantly after vaccination with irradiated L3 larvae, were unchanged after vaccination in basophil-depleted mice. These findings demonstrate that basophils help establish the immune responses responsible for irradiated L3 vaccine protection.

  20. Immune responses induced by repeated treatment do not result in protective immunity to Schistosoma haematobium: interleukin (IL)-5 and IL-10 responses.

    PubMed

    van den Biggelaar, Anita H J; Borrmann, Steffen; Kremsner, Peter; Yazdanbakhsh, Maria

    2002-11-15

    The hypothesis that repeated treatments enhance acquired immunity against schistosomes by stimulating strong T helper 2 responses was tested. Schistosoma haematobium-infected schoolchildren were monitored for 3 years. During the first 2 years, children who did not receive chemotherapy were compared with those treated once or repeatedly. After specific immune responses were measured at 24 months, praziquantel was given to all children to clear any schistosome infections. Twelve months later, the infection status of the children was determined and compared with cytokine profiles at month 24, to gain insight into which immunologic profiles can predict resistance or susceptibility to schistosome infections. Repeated treatment led to high specific levels of interleukin (IL)-5 and low interferon-gamma production but did not protect against reinfection. After adjusting for variables, such as sex, age, and infection status at study onset, high levels of parasite-specific IL-10 were a risk factor for reinfection, and high levels of IL-5 were associated with hematuria development. PMID:12404164

  1. Predicted impact of mass drug administration on the development of protective immunity against Schistosoma haematobium.

    PubMed

    Mitchell, Kate M; Mutapi, Francisca; Mduluza, Takafira; Midzi, Nicholas; Savill, Nicholas J; Woolhouse, Mark E J

    2014-01-01

    Previous studies suggest that protective immunity against Schistosoma haematobium is primarily stimulated by antigens from dying worms. Praziquantel treatment kills adult worms, boosting antigen exposure and protective antibody levels. Current schistosomiasis control efforts use repeated mass drug administration (MDA) of praziquantel to reduce morbidity, and may also reduce transmission. The long-term impact of MDA upon protective immunity, and subsequent effects on infection dynamics, are not known. A stochastic individual-based model describing levels of S. haematobium worm burden, egg output and protective parasite-specific antibody, which has previously been fitted to cross-sectional and short-term post-treatment egg count and antibody patterns, was used to predict dynamics of measured egg output and antibody during and after a 5-year MDA campaign. Different treatment schedules based on current World Health Organisation recommendations as well as different assumptions about reductions in transmission were investigated. We found that antibody levels were initially boosted by MDA, but declined below pre-intervention levels during or after MDA if protective immunity was short-lived. Following cessation of MDA, our models predicted that measured egg counts could sometimes overshoot pre-intervention levels, even if MDA had had no effect on transmission. With no reduction in transmission, this overshoot occurred if protective immunity was short-lived. This implies that disease burden may temporarily increase following discontinuation of treatment, even in the absence of any reduction in the overall transmission rate. If MDA was additionally assumed to reduce transmission, a larger overshoot was seen across a wide range of parameter combinations, including those with longer-lived protective immunity. MDA may reduce population levels of immunity to urogenital schistosomiasis in the long-term (3-10 years), particularly if transmission is reduced. If MDA is stopped while

  2. The Community-Acquired Pneumonia immunization Trial in Adults (CAPiTA): what is the future of pneumococcal conjugate vaccination in elderly?

    PubMed

    van Werkhoven, Cornelis H; Bonten, Marc J M

    2015-01-01

    Pneumococcal community-acquired pneumonia (PCAP) and invasive pneumococcal disease (IPD) are important causes of morbidity and mortality in elderly. In the Community-Acquired Pneumonia immunization Trial in Adults (CAPiTA), a randomized double-blind placebo-controlled trial of 84,496 community-dwelling immunocompetent adults over 65 years of age, the 13-valent pneumococcal conjugate vaccine (PCV13) reduced the incidence of first episode of vaccine-type (VT) PCAP with 38 and of VT-IPD with 76% in the modified intention-to-treat population. In The Netherlands, where PCV7 immunization of newborns was introduced in 2007 and replaced by PCV10 in 2011, introduction of PCV13 immunization of elderly--based on 2012 data--would be highly cost effective. However, this is probably different in countries where the VT disease burden has declined more, for instance due to herd effects following child immunization with PCV13. Apart from cost-effectiveness analyses, ethical aspects of PCAP prevention should be taken into account in policy making for pneumococcal vaccination in elderly.

  3. Mucosal immunization with filamentous hemagglutinin protects against Bordetella pertussis respiratory infection.

    PubMed Central

    Shahin, R D; Amsbaugh, D F; Leef, M F

    1992-01-01

    Mucosal immunization of mice with purified Bordetella pertussis filamentous hemagglutinin (FHA), by either the respiratory or the gut route, was found to protect against B. pertussis infection of the trachea and lungs. Intranasal immunization of BALB/c and (C57BL/6 x C3H/HeN)F1 adult female mice with FHA prior to B. pertussis aerosol challenge resulted in a 2 to 3 log reduction in number of bacteria recovered from the lungs and the tracheas of immunized mice in comparison to unimmunized controls. Intraduodenal immunization of adult mice with FHA before infection also resulted in approximately a 2 log reduction in the recovery of bacteria from the lungs and the tracheas of immunized mice in comparison to unimmunized controls. Immunoglobulin A and immunoglobulin G anti-FHA were both detected in bronchoalveolar lavage fluids of mucosally immunized mice. Limiting dilution analysis revealed a 60-fold increase in the frequency of FHA-specific B cells isolated from the lungs of mice immunized intranasally with FHA in comparison to unimmunized control mice. These data suggest that both gut and respiratory mucosal immunization with a major adhesin of B. pertussis generates a specific immune response in the respiratory tract that may serve as one means of mitigating subsequent B. pertussis respiratory infection. Images PMID:1548072

  4. Insect immunity: oral exposure to a bacterial pathogen elicits free radical response and protects from a recurring infection

    PubMed Central

    2014-01-01

    Background Previous exposure to a pathogen can help organisms cope with recurring infection. This is widely recognised in vertebrates, but increasing occasions are also being reported in invertebrates where this phenomenon is referred to as immune priming. However, the mechanisms that allow acquired pathogen resistance in insects remain largely unknown. Results We studied the priming of bacterial resistance in the larvae of the tiger moth, Parasemia plantaginis using two gram-negative bacteria, a pathogenic Serratia marcescens and a non-pathogenic control, Escherichia coli. A sublethal oral dose of S. marcescens provided the larvae with effective protection against an otherwise lethal septic infection with the same pathogen five days later. At the same time, we assessed three anti-bacterial defence mechanisms from the larvae that had been primarily exposed to the bacteria via contaminated host plant. Results showed that S. marcescens had induced a higher amount of reactive oxygen species (ROS) in the larval haemolymph, possibly protecting the host from the recurring infection. Conclusions Our study supports the growing evidence of immune priming in insects. It shows that activation of the protective mechanism requires a specific induction, rather than a sheer exposure to any gram-negative bacteria. The findings indicate that systemic pathogen recognition happens via the gut, and suggest that persistent loitering of immune elicitors or anti-microbial molecules are a possible mechanism for the observed prophylaxis. The self-harming effects of ROS molecules are well known, which indicates a potential cost of increased resistance. Together these findings could have important implications on the ecological and epidemiological processes affecting insect and pathogen populations. PMID:24602309

  5. Gut Microbiota Elicits a Protective Immune Response against Malaria Transmission

    PubMed Central

    Yilmaz, Bahtiyar; Portugal, Silvia; Tran, Tuan M.; Gozzelino, Raffaella; Ramos, Susana; Gomes, Joana; Regalado, Ana; Cowan, Peter J.; d’Apice, Anthony J.F.; Chong, Anita S.; Doumbo, Ogobara K.; Traore, Boubacar; Crompton, Peter D.; Silveira, Henrique; Soares, Miguel P.

    2014-01-01

    Summary Glycosylation processes are under high natural selection pressure, presumably because these can modulate resistance to infection. Here, we asked whether inactivation of the UDP-galactose:β-galactoside-α1-3-galactosyltransferase (α1,3GT) gene, which ablated the expression of the Galα1-3Galβ1-4GlcNAc-R (α-gal) glycan and allowed for the production of anti-α-gal antibodies (Abs) in humans, confers protection against Plasmodium spp. infection, the causative agent of malaria and a major driving force in human evolution. We demonstrate that both Plasmodium spp. and the human gut pathobiont E. coli O86:B7 express α-gal and that anti-α-gal Abs are associated with protection against malaria transmission in humans as well as in α1,3GT-deficient mice, which produce protective anti-α-gal Abs when colonized by E. coli O86:B7. Anti-α-gal Abs target Plasmodium sporozoites for complement-mediated cytotoxicity in the skin, immediately after inoculation by Anopheles mosquitoes. Vaccination against α-gal confers sterile protection against malaria in mice, suggesting that a similar approach may reduce malaria transmission in humans. PaperFlick PMID:25480293

  6. Protecting children's health. CHA's immunization program helps organizations increase vaccination rates in their communities.

    PubMed

    Wiener, J O; Trocchio, J

    1992-09-01

    In response to the increasing outbreaks of vaccine-preventable diseases in the United States, the Catholic Health Association (CHA) has developed a new resource to help its members launch programs that will increase immunization rates among children in their service area. Vaccines are the building blocks of basic primary care. But society and the healthcare system have erected barriers that prevent children from being fully immunized. Impediments include missed opportunities, cost barriers, and facility and resource barriers. Catholic healthcare providers can help eliminate these barriers and ensure that all children in their service areas are vaccinated by assessing their immunization resources, seeking out unvaccinated children, and collaborating with community organizations and agencies. CHA's immunization campaign will guide Catholic healthcare providers as they protect children from preventable diseases. Immunization may help reduce the costs of emergency and acute care for conditions that could have been prevented. PMID:10120199

  7. Expression library immunization confers protection against Mycobacterium avium subsp. paratuberculosis infection.

    PubMed

    Huntley, J F; Stabel, J R; Paustian, M L; Reinhardt, T A; Bannantine, J P

    2005-10-01

    Currently, paratuberculosis vaccines are comprised of crude whole-cell preparations of Mycobacterium avium subsp. paratuberculosis. Although effective in reducing clinical disease and fecal shedding, these vaccines have severe disadvantages as well, including seroconversion of vaccinated animals and granulomatous lesions at the site of vaccination. DNA vaccines can offer an alternative approach that may be safer and elicit more protective responses. In an effort to identify protective M. avium subsp. paratuberculosis sequences, a genomic DNA expression library was generated and subdivided into pools of clones (approximately 1,500 clones/pool). The clone pools were evaluated to determine DNA vaccine efficacy by immunizing mice via gene gun delivery and challenging them with live, virulent M. avium subsp. paratuberculosis. Four clone pools resulted in a significant reduction in the amount of M. avium subsp. paratuberculosis recovered from mouse tissues compared to mice immunized with other clone pools and nonvaccinated, infected control mice. One of the protective clone pools was further partitioned into 10 clone arrays of 108 clones each, and four clone arrays provided significant protection from both spleen and mesenteric lymph node colonization by M. avium subsp. paratuberculosis. The nucleotide sequence of each clone present in the protective pools was determined, and coding region functions were predicted by computer analysis. Comparison of the protective clone array sequences implicated 26 antigens that may be responsible for protection in mice. This study is the first study to demonstrate protection against M. avium subsp. paratuberculosis infection with expression library immunization. PMID:16177367

  8. Targets for the Induction of Protective Immunity Against Influenza A Viruses

    PubMed Central

    Bodewes, Rogier; Osterhaus, Albert D.M.E; Rimmelzwaan, Guus F.

    2010-01-01

    The current pandemic caused by the new influenza A(H1N1) virus of swine origin and the current pandemic threat caused by the highly pathogenic avian influenza A viruses of the H5N1 subtype have renewed the interest in the development of vaccines that can induce broad protective immunity. Preferably, vaccines not only provide protection against the homologous strains, but also against heterologous strains, even of another subtype. Here we describe viral targets and the arms of the immune response involved in protection against influenza virus infections such as antibodies directed against the hemagglutinin, neuraminidase and the M2 protein and cellular immune responses directed against the internal viral proteins. PMID:21994606

  9. NH4+ protects tomato plants against Pseudomonas syringae by activation of systemic acquired acclimation.

    PubMed

    Fernández-Crespo, Emma; Scalschi, Loredana; Llorens, Eugenio; García-Agustín, Pilar; Camañes, Gemma

    2015-11-01

    NH4 (+) nutrition provokes mild toxicity by enhancing H2O2 accumulation, which acts as a signal activating systemic acquired acclimation (SAA). Until now, induced resistance mechanisms in response to an abiotic stimulus and related to SAA were only reported for exposure to a subsequent abiotic stress. Herein, the first evidence is provided that this acclimation to an abiotic stimulus induces resistance to later pathogen infection, since NH4 (+) nutrition (N-NH4 (+))-induced resistance (NH4 (+)-IR) against Pseudomonas syringae pv tomato DC3000 (Pst) in tomato plants was demonstrated. N-NH4 (+) plants displayed basal H2O2, abscisic acid (ABA), and putrescine (Put) accumulation. H2O2 accumulation acted as a signal to induce ABA-dependent signalling pathways required to prevent NH4 (+) toxicity. This acclimatory event provoked an increase in resistance against later pathogen infection. N-NH4 (+) plants displayed basal stomatal closure produced by H2O2 derived from enhanced CuAO and rboh1 activity that may reduce the entry of bacteria into the mesophyll, diminishing the disease symptoms as well as strongly inducing the oxidative burst upon Pst infection, favouring NH4 (+)-IR. Experiments with inhibitors of Put accumulation and the ABA-deficient mutant flacca demonstrated that Put and ABA downstream signalling pathways are required to complete NH4 (+)-IR. The metabolic profile revealed that infected N-NH4 (+) plants showed greater ferulic acid accumulation compared with control plants. Although classical salicylic acid (SA)-dependent responses against biotrophic pathogens were not found, the important role of Put in the resistance of tomato against Pst was demonstrated. Moreover, this work revealed the cross-talk between abiotic stress acclimation (NH4 (+) nutrition) and resistance to subsequent Pst infection.

  10. NH4 + protects tomato plants against Pseudomonas syringae by activation of systemic acquired acclimation

    PubMed Central

    Fernández-Crespo, Emma; Scalschi, Loredana; Llorens, Eugenio; García-Agustín, Pilar; Camañes, Gemma

    2015-01-01

    NH4 + nutrition provokes mild toxicity by enhancing H2O2 accumulation, which acts as a signal activating systemic acquired acclimation (SAA). Until now, induced resistance mechanisms in response to an abiotic stimulus and related to SAA were only reported for exposure to a subsequent abiotic stress. Herein, the first evidence is provided that this acclimation to an abiotic stimulus induces resistance to later pathogen infection, since NH4 + nutrition (N-NH4 +)-induced resistance (NH4 +-IR) against Pseudomonas syringae pv tomato DC3000 (Pst) in tomato plants was demonstrated. N-NH4 + plants displayed basal H2O2, abscisic acid (ABA), and putrescine (Put) accumulation. H2O2 accumulation acted as a signal to induce ABA-dependent signalling pathways required to prevent NH4 + toxicity. This acclimatory event provoked an increase in resistance against later pathogen infection. N-NH4 + plants displayed basal stomatal closure produced by H2O2 derived from enhanced CuAO and rboh1 activity that may reduce the entry of bacteria into the mesophyll, diminishing the disease symptoms as well as strongly inducing the oxidative burst upon Pst infection, favouring NH4 +-IR. Experiments with inhibitors of Put accumulation and the ABA-deficient mutant flacca demonstrated that Put and ABA downstream signalling pathways are required to complete NH4 +-IR. The metabolic profile revealed that infected N-NH4 + plants showed greater ferulic acid accumulation compared with control plants. Although classical salicylic acid (SA)-dependent responses against biotrophic pathogens were not found, the important role of Put in the resistance of tomato against Pst was demonstrated. Moreover, this work revealed the cross-talk between abiotic stress acclimation (NH4 + nutrition) and resistance to subsequent Pst infection. PMID:26246613

  11. Intranasal immunization with protective antigen of Bacillus anthracis induces a long-term immunological memory response.

    PubMed

    Woo, Sun-Je; Kang, Seok-Seong; Park, Sung-Moo; Yang, Jae Seung; Song, Man Ki; Yun, Cheol-Heui; Han, Seung Hyun

    2015-10-01

    Although intranasal vaccination has been shown to be effective for the protection against inhalational anthrax, establishment of long-term immunity has yet to be achieved. Here, we investigated whether intranasal immunization with recombinant protective antigen (rPA) of Bacillus anthracis induces immunological memory responses in the mucosal and systemic compartments. Intranasal immunization with rPA plus cholera toxin (CT) sustained PA-specific antibody responses for 6 months in lung, nasal washes, and vaginal washes as well as serum. A significant induction of PA-specific memory B cells was observed in spleen, cervical lymph nodes (CLNs) and lung after booster immunization. Furthermore, intranasal immunization with rPA plus CT remarkably generated effector memory CD4(+) T cells in the lung. PA-specific CD4(+) T cells preferentially increased the expression of Th1- and Th17-type cytokines in lung, but not in spleen or CLNs. Collectively, the intranasal immunization with rPA plus CT promoted immunologic memory responses in the mucosal and systemic compartments, providing long-term immunity.

  12. Tailored immune responses: novel effector helper T cell subsets in protective immunity.

    PubMed

    Kara, Ervin E; Comerford, Iain; Fenix, Kevin A; Bastow, Cameron R; Gregor, Carly E; McKenzie, Duncan R; McColl, Shaun R

    2014-02-01

    Differentiation of naïve CD4⁺ cells into functionally distinct effector helper T cell subsets, characterised by distinct "cytokine signatures," is a cardinal strategy employed by the mammalian immune system to efficiently deal with the rapidly evolving array of pathogenic microorganisms encountered by the host. Since the T(H)1/T(H)2 paradigm was first described by Mosmann and Coffman, research in the field of helper T cell biology has grown exponentially with seven functionally unique subsets having now been described. In this review, recent insights into the molecular mechanisms that govern differentiation and function of effector helper T cell subsets will be discussed in the context of microbial infections, with a focus on how these different helper T cell subsets orchestrate immune responses tailored to combat the nature of the pathogenic threat encountered.

  13. The balance between protective and pathogenic immune responses in the TB-infected lung.

    PubMed

    Orme, Ian M; Robinson, Richard T; Cooper, Andrea M

    2015-01-01

    Tuberculosis is a disease of the lung, and efficient transmission is dependent on the generation of a lesion in the lung, which results in a bacterium-laden cough. Mycobacterium tuberculosis (Mtb) is able to manipulate both the innate and acquired immune response of the host. This manipulation results in an effective CD4(+) T cell response that limits disease throughout the body but can also promote the development of progressively destructive lesions in the lung. In this way Mtb infection can result in an ambulatory individual who has a lesion in the lung capable of transmitting Mtb. The inflammatory environment within the lung lesion is manipulated by Mtb throughout infection and can limit the expression of acquired immunity by a variety of pathways.

  14. DNA Vaccines: Protective Immunizations by Parenteral, Mucosal, and Gene-Gun Inoculations

    NASA Astrophysics Data System (ADS)

    Fynan, Ellen F.; Webster, Robert G.; Fuller, Deborah H.; Haynes, Joel R.; Santoro, Joseph C.; Robinson, Harriet L.

    1993-12-01

    Plasmid DNAs expressing influenza virus hemagglutinin glycoproteins have been tested for their ability to raise protective immunity against lethal influenza challenges of the same subtype. In trials using two inoculations of from 50 to 300 μg of purified DNA in saline, 67-95% of test mice and 25-63% of test chickens have been protected against a lethal influenza challenge. Parenteral routes of inoculation that achieved good protection included intramuscular and intravenous injections. Successful mucosal routes of vaccination included DNA drops administered to the nares or trachea. By far the most efficient DNA immunizations were achieved by using a gene gun to deliver DNA-coated gold beads to the epidermis. In mice, 95% protection was achieved by two immunizations with beads loaded with as little as 0.4 μg of DNA. The breadth of routes supporting successful DNA immunizations, coupled with the very small amounts of DNA required for gene-gun immunizations, highlight the potential of this remarkably simple technique for the development of subunit vaccines.

  15. Apical Organelle Secretion by Toxoplasma Controls Innate and Adaptive Immunity and Mediates Long-Term Protection.

    PubMed

    Sloves, Pierre-Julien; Mouveaux, Thomas; Ait-Yahia, Saliha; Vorng, Han; Everaere, Laetitia; Sangare, Lamba Omar; Tsicopoulos, Anne; Tomavo, Stanislas

    2015-11-01

    Apicomplexan parasites have unique apical rhoptry and microneme secretory organelles that are crucial for host infection, although their role in protection against Toxoplasma gondii infection is not thoroughly understood. Here, we report a novel function of the endolysosomal T. gondii sortilin-like receptor (TgSORTLR), which mediates trafficking to functional apical organelles and their subsequent secretion of virulence factors that are critical to the induction of sterile immunity against parasite reinfection. We further demonstrate that the T. gondii armadillo repeats-only protein (TgARO) mutant, which is deficient only in apical secretion of rhoptries, is also critical in mounting protective immunity. The lack of TgSORTLR and TgARO proteins completely inhibited T-helper 1-dependent adaptive immunity and compromised the function of natural killer T-cell-mediated innate immunity. Our findings reveal an essential role for apical secretion in promoting sterile protection against T. gondii and provide strong evidence for rhoptry-regulated discharge of antigens as a key effector for inducing protective immunity.

  16. Determining Immune System Suppression versus CNS Protection for Pharmacological Interventions in Autoimmune Demyelination.

    PubMed

    Evonuk, Kirsten S; Moseley, Carson E; Doyle, Ryan E; Weaver, Casey T; DeSilva, Tara M

    2016-01-01

    A major hallmark of the autoimmune demyelinating disease multiple sclerosis (MS) is immune cell infiltration into the brain and spinal cord resulting in myelin destruction, which not only slows conduction of nerve impulses, but causes axonal injury resulting in motor and cognitive decline. Current treatments for MS focus on attenuating immune cell infiltration into the central nervous system (CNS). These treatments decrease the number of relapses, improving quality of life, but do not completely eliminate relapses so long-term disability is not improved. Therefore, therapeutic agents that protect the CNS are warranted. In both animal models as well as human patients with MS, T cell entry into the CNS is generally considered the initiating inflammatory event. In order to assess if a drug protects the CNS, any potential effects on immune cell infiltration or proliferation in the periphery must be ruled out. This protocol describes how to determine whether CNS protection observed after drug intervention is a consequence of attenuating CNS-infiltrating immune cells or blocking death of CNS cells during inflammatory insults. The ability to examine MS treatments that are protective to the CNS during inflammatory insults is highly critical for the advancement of therapeutic strategies since current treatments reduce, but do not completely eliminate, relapses (i.e., immune cell infiltration), leaving the CNS vulnerable to degeneration. PMID:27685467

  17. Role of CD4(+) and CD8α(+) T cells in protective immunity against Edwardsiella tarda infection of ginbuna crucian carp, Carassius auratus langsdorfii.

    PubMed

    Yamasaki, Masatoshi; Araki, Kyosuke; Nakanishi, Teruyuki; Nakayasu, Chihaya; Yamamoto, Atsushi

    2014-01-01

    Edwardsiella tarda is an intracellular pathogen that causes edwardsiellosis in fish. Our previous study suggests that cell-mediated immunity (CMI) plays an essential role in protection against E. tarda infection. In the present study, we adoptively transferred T-cell subsets sensitized with E. tarda to isogenic naïve ginbuna crucian carp to determination the T-cell subsets involved in protecting fish from E. tarda infection. Recipients of CD4(+) and CD8α(+) cells acquired significant resistance to infection with E. tarda 8 days after sensitization, indicating that helper T cells and cytotoxic T lymphocytes plays crucial roles in protective immunity to E. tarda. Moreover, transfer of sensitized CD8α(+) cells up-regulated the expression of genes encoding interferon-γ (IFN-γ) and perforin, suggesting that protective immunity to E. tarda involves cell-mediated cytotoxicity and interferon-γ-mediated induction of CMI. The results establish that CMI plays a crucial role in immunity against E. tarda. These findings provide novel insights into understanding the role of CMI to intracellular pathogens of fish.

  18. Adjuvanticity and protective immunity elicited by Leishmania donovani antigens encapsulated in positively charged liposomes.

    PubMed Central

    Afrin, F; Ali, N

    1997-01-01

    In the search for a leishmaniasis vaccine, extensive studies of cutaneous leishmaniasis have been carried out. Investigations in this regard with the visceral form are limited. As an initial step in the identification of the protective molecules, leishmanial antigens extracted from the membranes of Leishmania donovani promastigotes, alone or in association with liposomes, were evaluated for their immunogenicity and ability to elicit a protective immune response against challenge infection. Intraperitoneal immunization of hamsters and BALB/c mice with the leishmanial antigens conferred protection against infection with the virulent promastigotes. Encapsulation in positively charged liposomes significantly enhanced the protective efficacy of these antigens. The splenic parasite burden of hamsters was reduced by 97% after 6 months of infection. BALB/c mice exhibited 87 and 81.3% protection in the liver and spleen, respectively, after 4 months of infection. These protected animals elicited profound delayed-type hypersensitivity and increased levels of Leishmania-specific immunoglobulin G (IgG) antibodies. Protection in mice also coincided with elevated levels of IgM and IgA antibodies, which decreased with disease progression in the control-infected animals. Although both IgG1 and IgG2a antibodies were present in the sera of infected mice, IgG1 appeared to be the predominant isotype, suggesting a preferential induction of the Th2 type of immune response over that of Th1. Effective stimulation of all the IgG isotypes, particularly IgG2a, after immunization with liposome encapsulated antigens seems to be responsible for the significant levels of resistance against the disease. Taken together, these data indicate a potential for the liposomal antigens as a vaccine which could trigger both humoral and cell-mediated immune responses. PMID:9169776

  19. Commensal-dendritic-cell interaction specifies a unique protective skin immune signature.

    PubMed

    Naik, Shruti; Bouladoux, Nicolas; Linehan, Jonathan L; Han, Seong-Ji; Harrison, Oliver J; Wilhelm, Christoph; Conlan, Sean; Himmelfarb, Sarah; Byrd, Allyson L; Deming, Clayton; Quinones, Mariam; Brenchley, Jason M; Kong, Heidi H; Tussiwand, Roxanne; Murphy, Kenneth M; Merad, Miriam; Segre, Julia A; Belkaid, Yasmine

    2015-04-01

    The skin represents the primary interface between the host and the environment. This organ is also home to trillions of microorganisms that play an important role in tissue homeostasis and local immunity. Skin microbial communities are highly diverse and can be remodelled over time or in response to environmental challenges. How, in the context of this complexity, individual commensal microorganisms may differentially modulate skin immunity and the consequences of these responses for tissue physiology remains unclear. Here we show that defined commensals dominantly affect skin immunity and identify the cellular mediators involved in this specification. In particular, colonization with Staphylococcus epidermidis induces IL-17A(+) CD8(+) T cells that home to the epidermis, enhance innate barrier immunity and limit pathogen invasion. Commensal-specific T-cell responses result from the coordinated action of skin-resident dendritic cell subsets and are not associated with inflammation, revealing that tissue-resident cells are poised to sense and respond to alterations in microbial communities. This interaction may represent an evolutionary means by which the skin immune system uses fluctuating commensal signals to calibrate barrier immunity and provide heterologous protection against invasive pathogens. These findings reveal that the skin immune landscape is a highly dynamic environment that can be rapidly and specifically remodelled by encounters with defined commensals, findings that have profound implications for our understanding of tissue-specific immunity and pathologies. PMID:25539086

  20. Influenza and pneumococcal pneumonia immunization. Protecting our high risk population.

    PubMed

    Siegel, B R; Mahan, C S; Witte, J J; Janowski, H T

    1990-06-01

    Pneumonia and influenza (P & I) constitute Florida's sixth leading cause of death. The P & I death rate in 1987, 10.5 per 100,000, was the highest since 1978. Major target groups for one or both vaccines used in prevention, as recommended by the Immunization Practices Advisory Committee (ACIP), include persons with chronic diseases of the heart or lungs, residents of nursing homes and other chronic care facilities, and persons aged 65 and older. Despite well-defined recommendations, vaccine coverage rates in Florida are as low as 30% in persons greater than or equal to 65 years of age. Knowledge and attitude surveys demonstrate that low coverage among various population groups may be due largely to insufficient awareness and/or negative attitudes regarding pneumococcal and influenza vaccines. Conversely, recommendations by physicians and other health care providers are strongly associated with receiving either vaccine. If the incidence of P & I is to decrease substantively in Florida, much wider use of the vaccines must occur. Because so many high-risk patients depend on private physicians for health care, their role is critical to the success of Florida public health strategies to reverse P & I trends.

  1. Therapeutic Enhancement of Protective Immunity during Experimental Leishmaniasis

    PubMed Central

    Divanovic, Senad; Trompette, Aurelien; Ashworth, Jamie I.; Rao, Marepalli B.; Karp, Christopher L.

    2011-01-01

    Background Leishmaniasis remains a significant cause of morbidity and mortality in the tropics. Available therapies are problematic due to toxicity, treatment duration and emerging drug resistance. Mouse models of leishmaniasis have demonstrated that disease outcome depends critically on the balance between effector and regulatory CD4+ T cell responses, something mirrored in descriptive studies of human disease. Recombinant IL-2/diphtheria toxin fusion protein (rIL-2/DTx), a drug that is FDA-approved for the treatment of cutaneous T cell lymphoma, has been reported to deplete regulatory CD4+ T cells. Methodology/Principal Findings We investigated the potential efficacy of rIL-2/DTx as adjunctive therapy for experimental infection with Leishmania major. Treatment with rIL-2/DTx suppressed lesional regulatory T cell numbers and was associated with significantly increased antigen-specific IFN-γ production, enhanced lesion resolution and decreased parasite burden. Combined administration of rIL-2/DTx and sodium stibogluconate had additive biological and therapeutic effects, allowing for reduced duration or dose of sodium stibogluconate therapy. Conclusions/Significance These data suggest that pharmacological suppression of immune counterregulation using a commercially available drug originally developed for cancer therapy may have practical therapeutic utility in leishmaniasis. Rational reinvestigation of the efficacy of drugs approved for other indications in experimental models of neglected tropical diseases has promise in providing new candidates to the drug discovery pipeline. PMID:21909452

  2. The protective effects of temporary immunity under imposed infection pressure.

    PubMed

    Swart, A N; Tomasi, M; Kretzschmar, M; Havelaar, A H; Diekmann, O

    2012-03-01

    The aim of this paper is to show in explicit detail that, due to the effects of waning and boosting of immunity, an increasing force of infection does not necessarily lead to an increase in the incidence of disease. Under certain conditions, a decrease of the force of infection may in fact lead to an increase of the incidence of disease. Thus we confirm and reinforce the conclusions from Águas et al. (2006), concerning pertussis. We do so, however, in the context of Campylobacter infections in humans deriving from animal reservoirs. For such an externally 'driven' epidemic we can ignore the transmission feedback cycle and treat the force of infection as a parameter. As this parameter is, to a certain extent, under public health control, our findings constitute an important warning: reducing exposure may not necessarily lead to a reduction in the occurrence of clinical illness. In a second part of the paper we relate the model parameters to the available data concerning campylobacteriosis.

  3. A VACCINE STRATEGY THAT INDUCES PROTECTIVE IMMUNITY AGAINST HEROIN

    PubMed Central

    Stowe, G. Neil; Vendruscolo, Leandro F.; Edwards, Scott; Schlosburg, Joel E.; Misra, Kaushik K.; Schulteis, Gery; Mayorov, Alexander V.; Zakhari, Joseph S.; Koob, George F.; Janda, Kim D.

    2011-01-01

    Heroin addiction is a wide-reaching problem with a spectrum of damaging social consequences. A vaccine capable of blocking heroin's effects could provide a long-lasting and sustainable adjunct to heroin addiction therapy. Heroin, however, presents a particularly challenging immunotherapeutic target as it is metabolized to multiple psychoactive molecules. To reconcile this dilemma we examined the idea of a singular vaccine with the potential to display multiple drug-like antigens; thus two haptens were synthesized, one heroin-like and another morphine-like in chemical structure. A key feature in this approach is that immunopresentation with the heroin-like hapten is thought to be immunochemically dynamic such that multiple haptens are simultaneously presented to the immune system. We demonstrate the significance of this approach though the extremely rapid generation of robust polyclonal antibody titers with remarkable specificity. Importantly, both the antinociceptive effects of heroin and acquisition of heroin self-administration were blocked in rats vaccinated using the heroin-like hapten. PMID:21692508

  4. Neonatal Immunization with Respiratory Syncytial Virus Glycoprotein Fragment Induces Protective Immunity in the Presence of Maternal Antibodies in Mice

    PubMed Central

    Noh, Youran; Shim, Byoung-Shik; Cheon, In Su; Rho, Semi; Kim, Hee Joo; Choi, Youngjoo; Kang, Chang-Yuil; Chang, Jun

    2013-01-01

    Abstract Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract infections in infants and the elderly worldwide. The significant morbidity and mortality associated with this infection underscores the urgent need for development of RSV vaccine. In this study, we first show that intranasal administration of RSV glycoprotein core fragment (Gcf) to neonatal mice can induce systemic humoral immune responses and protective immunity against RSV without causing lung eosinophilia, although antibody response was shifted to a Th2 response. Next, we examined whether the presence of maternal anti-RSV antibodies would affect the responsiveness and protection efficacy of Gcf in newborn mice, since infants can possess RSV-specific maternal antibodies due to frequent RSV re-infections to adults. Intranasal administration of Gcf induced antibody response and increased IFNγ secretion and protected mice against RSV challenge without severe lung eosinophilia, even in the presence of high levels of RSV-specific maternal antibodies. Thus, our findings suggest that Gcf may be an effective and safe RSV vaccine during the neonatal period. PMID:23869549

  5. Immunological responses and protection in Chinese giant salamander Andrias davidianus immunized with inactivated iridovirus.

    PubMed

    Liu, Wenzhi; Xu, Jin; Ma, Jie; LaPatra, Scott E; Meng, Yan; Fan, Yuding; Zhou, Yong; Yang, Xin; Zeng, Lingbing

    2014-12-01

    Chinese giant salamander hemorrhage is a newly emerged infectious disease in China and has caused huge economic losses. The causative pathogen has been identified as the giant salamander iridovirus (GSIV). In this study, the immunological responses and protection in Chinese giant salamander immunized with β-propiolactone inactivated GSIV are reported. Red and white blood cell counting and classification, phagocytic activity, neutralizing antibody titration, immune-related gene expression and determination of the relative percent survival were evaluated after vaccination. The red and white blood cell counts showed that the numbers of erythrocytes and leukocytes in the peripheral blood of immunized Chinese giant salamanders increased significantly on days 4 and 7 post-injection (P<0.01). Additionally, the differential leukocyte count of monocytes and neutrophils were significantly different compared to the control group (P<0.01); the percentage of lymphocytes was 70.45±7.52% at day 21. The phagocytic percentage and phagocytic index was 38.78±4.33% and 3.75±0.52, respectively, at day 4 post-immunization which were both significantly different compared to the control group (P<0.01). The serum neutralizing antibody titer increased at day 14 post-immunization and reached the highest titer (341±9.52) at day 21. The quantitative PCR analysis revealed that the immunization significantly up-regulated the expression of immune related genes TLR-9 and MyD88 the first two weeks after immunization. The challenge test conducted at day 30 post-injection demonstrated that the immunized group produced a relative survival of 72%. These results indicate that the inactivated GSIV could elicit significant non-specific and specific immunological responses in Chinese giant salamander that resulted in significant protection against GSIV induced disease.

  6. Protective immunity induced in mice by F0 and FII antigens purified from Paracoccidioides brasiliensis.

    PubMed

    Diniz, S N; Reis, B S; Goes, T S; Zouain, C S; Leite, M F; Goes, A M

    2004-01-01

    Paracoccidioides brasiliensis causes a chronic granulomatous mycosis prevalent in South America, and cell-mediated immunity represents the principal mode of protection against this fungal infection. We investigated whether immunization with P. brasiliensis antigens fractionated by anionic chromatography on fast protein liquid chromatography (FPLC) could elicit protective immunity. BALB/c mice were immunized by subcutaneous injection of either 10 microg fractions 0 (F0), II (FII) or III (FIII) in the presence of 100 microg of Corynebacterium parvum and 1 mg of Al(OH)(3) and challenged with pathogenic P. brasiliensis strain. Mice immunized with F0 presented cellular and humoral immune responses with significant production of IFN-gamma, and high levels of IgG2a and IgG3 isotypes. Immunization with FII induced significant production of IFN-gamma and IL-10 associated with high levels of IgG1 and IgG2a. It was demonstrated that immunization with F0 or FII promoted significant decrease of organ colony-forming units (CFUs) in the lung after challenge infection without fungi dissemination to the spleen or liver. In contrast, FIII immunized mice develop a progressive disseminated disease to spleen and liver presented significant levels of INF-gamma, IL-10 or TGF-beta associated with high production of IgG1 and IgG2a with low production of IgG2b and IgG3 after challenge infection. Taken together, these findings suggest that antigens of F0 and FII are reliable vaccine candidates against the paracoccidioidomycosis. PMID:14670331

  7. Naturally acquired antibodies to Bacillus anthracis protective antigen in vultures of southern Africa.

    PubMed

    Turnbull, P C B; Diekmann, M; Kilian, J W; Versfeld, W; De Vos, V; Arntzen, L; Wolter, K; Bartels, P; Kotze, A

    2008-06-01

    Sera from 19 wild caught vultures in northern Namibia and 15 (12 wild caught and three captive bred but with minimal histories) in North West Province, South Africa, were examined by an enzyme-linked immunosorbent assay (ELISA) for antibodies to the Bacillus anthracis toxin protective antigen (PA). As assessed from the baseline established with a control group of ten captive reared vultures with well-documented histories, elevated titres were found in 12 of the 19 (63%) wild caught Namibian birds as compared with none of the 15 South African ones. There was a highly significant difference between the Namibian group as a whole and the other groups (P < 0.001) and no significant difference between the South African and control groups (P > 0.05). Numbers in the Namibian group were too small to determine any significances in species-, sex- or age-related differences within the raw data showing elevated titres in four out of six Cape Vultures, Gyps coprotheres, six out of ten White-backed Vultures, Gyps africanus, and one out of three Lappet-faced Vultures, Aegypius tracheliotus, or in five of six males versus three of seven females, and ten of 15 adults versus one of four juveniles. The results are in line with the available data on the incidence of anthrax in northern Namibia and South Africa and the likely contact of the vultures tested with anthrax carcasses. It is not known whether elevated titre indicates infection per se in vultures or absorption of incompletely digested epitopes of the toxin or both. The results are discussed in relation to distances travelled by vultures as determined by new tracking techniques, how serology can reveal anthrax activity in an area and the issue of the role of vultures in transmission of anthrax. PMID:18788202

  8. Naturally acquired antibodies to Bacillus anthracis protective antigen in vultures of southern Africa.

    PubMed

    Turnbull, P C B; Diekmann, M; Kilian, J W; Versfeld, W; De Vos, V; Arntzen, L; Wolter, K; Bartels, P; Kotze, A

    2008-06-01

    Sera from 19 wild caught vultures in northern Namibia and 15 (12 wild caught and three captive bred but with minimal histories) in North West Province, South Africa, were examined by an enzyme-linked immunosorbent assay (ELISA) for antibodies to the Bacillus anthracis toxin protective antigen (PA). As assessed from the baseline established with a control group of ten captive reared vultures with well-documented histories, elevated titres were found in 12 of the 19 (63%) wild caught Namibian birds as compared with none of the 15 South African ones. There was a highly significant difference between the Namibian group as a whole and the other groups (P < 0.001) and no significant difference between the South African and control groups (P > 0.05). Numbers in the Namibian group were too small to determine any significances in species-, sex- or age-related differences within the raw data showing elevated titres in four out of six Cape Vultures, Gyps coprotheres, six out of ten White-backed Vultures, Gyps africanus, and one out of three Lappet-faced Vultures, Aegypius tracheliotus, or in five of six males versus three of seven females, and ten of 15 adults versus one of four juveniles. The results are in line with the available data on the incidence of anthrax in northern Namibia and South Africa and the likely contact of the vultures tested with anthrax carcasses. It is not known whether elevated titre indicates infection per se in vultures or absorption of incompletely digested epitopes of the toxin or both. The results are discussed in relation to distances travelled by vultures as determined by new tracking techniques, how serology can reveal anthrax activity in an area and the issue of the role of vultures in transmission of anthrax.

  9. HPV vaccine: an overview of immune response, clinical protection, and new approaches for the future

    PubMed Central

    2010-01-01

    Although long-term protection is a key-point in evaluating HPV-vaccine over time, there is currently inadequate information on the duration of HPV vaccine-induced immunity and on the mechanisms related to the activation of immune-memory. Longer-term surveillance in a vaccinated population is needed to identify waning immunity, evaluating any requirements for booster immunizations to assess vaccine efficacy against HPV-diseases. Current prophylactic vaccines have the primary end-points to protect against HPV-16 and 18, the genotypes more associated to cervical cancer worldwide. Nevertheless, data from many countries demonstrate the presence, at significant levels, of HPVs that are not included in the currently available vaccine preparations, indicating that these vaccines could be less effective in a particular area of the world. The development of vaccines covering a larger number of HPVs presents the most complex challenge for the future. Therefore, long term immunization and cross-protection of HPV vaccines will be discussed in light of new approaches for the future. PMID:20979636

  10. Immunogenic recombinant Burkholderia pseudomallei MprA serine protease elicits protective immunity in mice

    PubMed Central

    Chin, Chui-Yoke; Tan, Swee-Chen; Nathan, Sheila

    2012-01-01

    Burkholderia pseudomallei is resistant to a diverse group of antimicrobials including third generation cephalosporins whilst quinolones and aminoglycosides have no reliable effect. As therapeutic options are limited, development of more effective forms of immunotherapy is vital to avoid a fatal outcome. In an earlier study, we reported on the B. pseudomallei serine MprA protease, which is relatively stable over a wide pH and temperature range and digests physiological proteins. The present study was carried out to evaluate the immunogenicity and protective efficacy of the MprA as a potential vaccine candidate. In BALB/c mice immunized with recombinant MprA protease (smBpF4), a significantly high IgG titer was detectable. Isotyping studies revealed that the smBpF4-specific antibodies produced were predominantly IgG1, proposing that immunization with smBpF4 triggered a Th2 immune response. Mice were immunized with smBpF4 and subsequently challenged with B. pseudomallei via the intraperitoneal route. Whilst control mice succumbed to the infection by day 9, smBpF4-immunized mice were protected against the lethal challenge and survived beyond 25 days post-infection. In conclusion, MprA is immunogenic in melioidosis patients whilst also eliciting a strong immune response upon bacterial challenge in mice and presents itself as a potential vaccine candidate for the treatment of melioidosis. PMID:22919676

  11. Protective effects of inhibitors of nitric oxide synthase in immune complex-induced vasculitis.

    PubMed Central

    Mulligan, M. S.; Moncada, S.; Ward, P. A.

    1992-01-01

    1. The ability of analogues of L-arginine (N-iminoethyl-L-ornithine (L-NIO), NG-monomethyl-L-arginine (L-NMMA), NG-nitro-L-arginine methyl ester (L-NAME) and NG-nitro-L-arginine (L-NNA)) to protect against inflammatory injury induced by activated neutrophils was investigated in rats following intradermal or intrapulmonary deposition of immune complexes. 2. The descending order of potency for protective effects of these analogues was: L-NIO > L-NMMA > L-NNA = L-NAME. The approximate IC50 value for L-NIO in the dermal vasculitis model was 65 microM. For all other compounds, the IC50 values were > 5 mM. 3. The protective effect of L-NIO in the skin was reversed in a dose-dependent manner by the presence of L-arginine, but not by D-arginine. L-Arginine also reversed the protective effects of L-NIO in immune complex-induced lung injury. 4. The protective effects of L-NIO were not associated with reductions in neutrophil accumulation, as measured by extraction from tissues of myeloperoxidase. 5. These data demonstrate that L-NIO has the most potent protective effects against immune complex-induced vascular injury induced by activated macrophages. Furthermore, they indicate that this injury is dependent upon the generation of nitric oxide. PMID:1281719

  12. Protective immunity induced by immunization with a live, cultured anaplasma marginale strain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite significant economic losses resulting from infection with Anaplasma marginale, a tick-transmitted rickettsial disease of cattle, available vaccines provide, at best, only partial protection against clinical disease. The green-fluorescent protein (GFP) expressing mutant of the A. marginale St...

  13. Protective immunity induced by immunization with a live, cultured Anaplasma marginale strain

    PubMed Central

    Hammac, G. Kenitra; Ku, Pei-Shin; Galletti, Maria F.; Noh, Susan M.; Scoles, Glen A.; Palmer, Guy H.; Brayton, Kelly A.

    2014-01-01

    Despite significant economic losses resulting from infection with Anaplasma marginale, a tick-transmitted rickettsial pathogen of cattle, available vaccines provide, at best, only partial protection against clinical disease. The green-fluorescent protein expressing mutant of the A. marginale St. Maries strain is a live, marked vaccine candidate (AmStM-GFP1). To test whether AmStM-GFP is safe and provides clinical protection, a group of calves was vaccinated, and clinical parameters, including percent parasitized erythrocytes (PPE), packed cell volume (PCV) and days required to reach peak bacteremia, were measured following inoculation and following tick challenge with wild type St Maries strain (AmStM). These clinical parameters were compared to those obtained during infection with the A. marginale subsp. centrale vaccine strain (A. centrale) or wild type AmStM. AmStM-GFP resulted in similar clinical parameters to A. centrale, but had a lower maximum PPE, smaller drop in PCV and took longer to reach peak bacteremia than wild type AmStM. AmStM-GFP provided clinical protection, yielding a stable PCV and low bacteremia following challenge, whereas A. centrale only afforded partial clinical protection. PMID:23664994

  14. Immune protection factors of chemical sunscreens measured in the local contact hypersensitivity model in humans.

    PubMed

    Wolf, Peter; Hoffmann, Christine; Quehenberger, Franz; Grinschgl, Stephan; Kerl, Helmut

    2003-11-01

    We conducted a randomized trial designed to calculate human in vivo immune protection factors of two sunscreen preparations in a model of ultraviolet-induced local suppression of the induction of contact hypersensitivity to 2,4-dinitrochlorobenzene. Seventy-five male subjects were exposed in a multistage study to multiples of their individual minimal erythema dose of solar-simulated ultraviolet radiation with or without protection by an ultraviolet B sunscreen (sun protection factor 5.2) or a broad-spectrum ultraviolet A + B sunscreen (sun protection factor 6.2). After 24 h subjects were sensitized with 50 microL of 0.0625% 2,4-dinitrochlorobenzene on a nonirradiated or ultraviolet-irradiated field on the buttock that was unprotected or protected by sunscreen. Three weeks after sensitization the subjects were challenged with varying concentrations of 2,4-dinitrochlorobenzene on their upper inner arm, and the contact hypersensitivity response was determined at 48 and 72 h based on a semiquantitative clinical score, contact hypersensitivity lesion diameters, and dermal skin edema measurement by 20 MHz ultrasound. The 50% immunosuppressive dose ranged from 0.63 to 0.79 minimal erythema dose, depending on the endpoint parameter. Both sunscreens offered significant immunoprotection (p = 0.014-0.002) and their immune protection factor ranged from 4.5 to 5.8 (ultraviolet B sunscreen) and from 7.7 to 11 (ultraviolet A + B sunscreen). The immune protection factor of the ultraviolet B sunscreen was similar to the sun protection factor (5.2), whereas the sunscreen with broad-spectrum ultraviolet A + B protection exhibited better immunoprotective capacity than predicted from the sun protection factor. PMID:14708610

  15. Augmentation of protective immune responses against viral infection by oral administration of schizophyllan

    PubMed Central

    Itoh, Wataru

    1997-01-01

    An oral administration of fungal polysaccharide schizophyllan has augmented protective immune responses to Sendai virus infection in mice and the rodshaped DNA virus of Penaeus japonicus (RV-PJ) infection in Kuruma shrimps. When schizophyllan was administered orally at a dose of 50 or 100 mg/kg body weight per day, the survival rates after virus challenge were significantly higher than those of the control groups. High phagocytic activities were observed in the haemocytes of the schizophyllan-fed shrimps.These results suggest that schizophyllan confers effective protection against viral infection by increasing antiviral immune responses, and that it could be used to boost immunity to virus infection in animals or in invertebrates. PMID:18472856

  16. A re-evaluation of the role of B cells in protective immunity to Chlamydia infection.

    PubMed

    Li, Lin-Xi; McSorley, Stephen J

    2015-04-01

    Chlamydia trachomatis is the etiological agent of the most commonly reported bacterial sexual transmitted infection (STI) in North America and Europe. The control of Chlamydia infection is hindered by the asymptomatic nature of initial infection but the consequence of untreated infection seriously threatens the reproductive health of young women. Unfortunately, there is no licensed vaccine for Chlamydia vaccine, in part due to our incomplete understanding of the immune response to Chlamydia urogenital infection. It has been well established that T cell-mediated immunity plays a dominant role in protective immunity against Chlamydia and thus the importance of B cells is somewhat underappreciated. Here, we summarize recent progress on understanding the role of B cells during Chlamydia genital tract infections and discuss how B cells and humoral immunity make an effective contribution to host defense against important intracellular pathogens, including Chlamydia.

  17. A re-evaluation of the role of B cells in protective immunity to Chlamydia infection

    PubMed Central

    Li, Lin-Xi; McSorley, Stephen J.

    2015-01-01

    Chlamydia trachomatis is the etiological agent of the most commonly reported bacterial sexual transmitted infection (STI) in North America and Europe. The control of Chlamydia infection is hindered by the asymptomatic nature of initial infection but the consequence of untreated infection seriously threatens the reproductive health of young women. Unfortunately, there is no licensed vaccine for Chlamydia vaccine, in part due to our incomplete understanding of the immune response to Chlamydia urogenital infection. It has been well established that T cell-mediated immunity plays a dominant role in protective immunity against Chlamydia and thus the importance of B cells is somewhat underappreciated. Here, we summarize recent progress on understanding the role of B cells during Chlamydia genital tract infections and discuss how B cells and humoral immunity make an effective contribution to host defense against important intracellular pathogens, including Chlamydia. PMID:25704502

  18. Passive immunization does not provide protection against experimental infection with Mycoplasma haemofelis.

    PubMed

    Sugiarto, Sarah; Spiri, Andrea M; Riond, Barbara; Novacco, Marilisa; Oestmann, Angelina; de Miranda, Luisa H Monteiro; Meli, Marina L; Boretti, Felicitas S; Hofmann-Lehmann, Regina; Willi, Barbara

    2016-01-01

    Mycoplasma haemofelis (Mhf) is the most pathogenic feline hemotropic mycoplasma. Cats infected with Mhf that clear bacteremia are protected from Mhf reinfection, but the mechanisms of protective immunity are unresolved. In the present study we investigated whether the passive transfer of antibodies from Mhf-recovered cats to naïve recipient cats provided protection against bacteremia and clinical disease following homologous challenge with Mhf; moreover, we characterized the immune response in the recipient cats. Ten specified pathogen-free (SPF) cats were transfused with pooled plasma from cats that had cleared Mhf bacteremia; five control cats received plasma from naïve SPF cats. After homologous challenge with Mhf, cats were monitored for 100 days using quantitative PCR, hematology, blood biochemistry, Coombs testing, flow cytometry, DnaK ELISA, and red blood cell (RBC) osmotic fragility (OF) measurement. Passively immunized cats were not protected against Mhf infection but, compared to control cats, showed significantly higher RBC OF and B lymphocyte (CD45R/B220(+)) counts and occasionally higher lymphocyte, monocyte and activated CD4(+) T lymphocyte (CD4(+)CD25(+)) counts; they also showed higher bilirubin, total protein and globulin levels compared to those of control cats. At times of peak bacteremia, a decrease in eosinophils and lymphocytes, as well as subsets thereof (B lymphocytes and CD5(+), CD4(+) and CD8(+) T lymphocytes), and an increase in monocytes were particularly significant in the passively immunized cats. In conclusion, passive immunization does not prevent bacteremia and clinical disease following homologous challenge with Mhf, but enhances RBC osmotic fragility and induces a pronounced immune response. PMID:27496124

  19. Severe Community-Acquired Pneumonia with Bacteremia Caused by Herbaspirillum aquaticum or Herbaspirillum huttiense in an Immune-Competent Adult

    PubMed Central

    Kimball, Joanna; Smith, L. Patrick; Salzer, William

    2015-01-01

    Herbaspirillum spp. are Gram-negative bacteria that inhabit soil and water. Infections caused by these organisms have been reported in immunocompromised hosts. We describe severe community-acquired pneumonia and bacteremia caused by Herbaspirillum aquaticum or H. huttiense in an immunocompetent adult male. PMID:26179298

  20. Intramuscular immunization of mice with live influenza virus is more immunogenic and offers greater protection than immunization with inactivated virus

    PubMed Central

    2011-01-01

    Background Influenza virus continues to cause significant hospitalization rates in infants and young children. A 2-dose regime of trivalent inactivated vaccine is required to generate protective levels of hemagglutination inhibiting (HAI) antibodies. A vaccine preparation with enhanced immunogenicity is therefore desirable. Methods Mice were inoculated intramuscularly (IM) with live and inactivated preparations of A/Wisconsin/67/2005 (H3N2). Serum cytokine levels, hemagglutinin (HA)-specific antibody responses and nucleoprotein (NP)-specific CD8+ T cell responses were compared between vaccinated groups, as well as to responses measured after intranasal infection. The protective efficacy of each vaccine type was compared by measuring virus titers in the lungs and weight loss of mice challenged intranasally with a heterosubtypic virus, A/PR/8/34 (H1N1). Results Intramuscular administration of live virus resulted in greater amounts of IFN-α, IL-12 and IFN-γ, HA-specific antibodies, and virus-specific CD8+ T cells, than IM immunization with inactivated virus. These increases corresponded with the live virus vaccinated group having significantly less weight loss and less virus in the lungs on day 7 following challenge with a sublethal dose of a heterosubtypic virus. Conclusions Inflammatory cytokines, antibody titers to HA and CD8+ T cell responses were greater to live than inactivated virus delivered IM. These increased responses correlated with greater protection against heterosubtypic virus challenge, suggesting that intramuscular immunization with live influenza virus may be a practical means to increase vaccine immunogenicity and to broaden protection in pediatric populations. PMID:21600020

  1. A Case of Mycobacterium riyadhense in an Acquired Immune Deficiency Syndrome (AIDS) Patient with a Suspected Paradoxical Response to Antituberculosis Therapy

    PubMed Central

    Badreddine, Samar Assem

    2016-01-01

    A 30-year-old male patient with acquired immune deficiency syndrome (AIDS) on highly active antiretroviral therapy (HAART) presented with clinical picture suggestive of pulmonary tuberculosis. He was commenced on antituberculosis therapy (ATT) with signs of improvement. Then he developed cervical lymph node abscess which was drained. Steroid was started for presumed paradoxical response to ATT which results in clinical regression. The culture result revealed Mycobacterium riyadhense. This report addresses the rarity of this bacteria in medical literature. It reviews clinical presentations and medical treatment particularly in the setting of coinfections. PMID:27703819

  2. Inhibition of priming for bovine respiratory syncytial virus-specific protective immune responses following parenteral vaccination of passively immune calves.

    PubMed

    Ellis, John; Gow, Sheryl; Bolton, Michael; Burdett, William; Nordstrom, Scott

    2014-12-01

    The effect of maternal antibodies (MatAb) on immunological priming by neonatal parenteral vaccination for bovine respiratory syncytial virus (BRSV) was addressed for the first time in experimental infection in 34 Holstein calves. Both vaccinated and control calves developed moderate to severe respiratory disease characteristic of acute BRSV infection. There were no differences in clinical signs, BRSV shed, arterial oxygen concentrations, or mortality between vaccinated and control calves after BRSV challenge approximately 11 wk after vaccination. There were no anamnestic antibody or cytokine responses in the vaccinates after challenge. Lung lesions were extensive in both groups, and although there was a statistically significant (P = 0.05) difference between groups, this difference was considered not biologically significant. These data indicate that stimulation of protective immune responses was inhibited by maternal antibodies when a combination modified-live BRSV vaccine was administered parenterally to young passively immune calves. Alternate routes of administration or different vaccine formulations should be used to successfully immunize young calves with good passive antibody transfer.

  3. Immune impairments and antibodies to HTLVIII/LAV in asymptomatic male homosexuals in Israel: relevance to the risk of acquired immune deficiency syndrome (AIDS).

    PubMed

    Bentwich, Z; Saxinger, C; Ben-Ishay, Z; Burstein, R; Berner, Y; Pecht, M; Trainin, N; Levin, S; Handzel, Z T

    1987-09-01

    We have studied 288 Israeli asymptomatic male homosexuals (MHS) to determine the prevalence of antibodies to HTLVI and HTLVIII and their correlation with impairments of the immune system and serum interferon (IFN). Seropositivity for HTLVI, HTLVIII, or both was found in 1.4, 8.3, and 0%, respectively. Significant decreases in the total peripheral T cells, TH cells, and TH/TS ratio as well as elevated alpha IFN serum levels were found in the MHS group in comparison with normal controls. Although no difference in the prevalence of either immune derangements or elevated serum IFN was observed between HTLVIII/LAV-seropositive and HTLVIII/LAV-seronegative MHS, the decreases in total T cells, TH cells, and TH/TS ratios were significantly greater in the seropositive MHS. These results indicate that (a) immune impairments and IFN system activation occur commonly in homosexuals, precede their exposure to HTLVIII/LAV, and probably reflect this group's increased risk for AIDS and (b) HTLVIII/LAV infection of MHS aggravates further their preexisting immune impairments.

  4. Cripto-1 vaccination elicits protective immunity against metastatic melanoma.

    PubMed

    Ligtenberg, M A; Witt, K; Galvez-Cancino, F; Sette, A; Lundqvist, A; Lladser, A; Kiessling, R

    2016-05-01

    Metastatic melanoma is a fatal disease that responds poorly to classical treatments but can be targeted by T cell-based immunotherapy. Cancer vaccines have the potential to generate long-lasting cytotoxic CD8(+) T cell responses able to eradicate established and disseminated tumors. Vaccination against antigens expressed by tumor cells with enhanced metastatic potential represents a highly attractive strategy to efficiently target deadly metastatic disease. Cripto-1 is frequently over-expressed in human carcinomas and melanomas, but is expressed only at low levels on normal differentiated tissues. Cripto-1 is particularly upregulated in cancer-initiating cells and is involved in cellular processes such as cell migration, invasion and epithelial-mesenchymal transition, which are hallmarks of aggressive cancer cells able to initiate metastatic disease. Here, we explored the potential of Cripto-1 vaccination to target metastatic melanoma in a preclinical model. Cripto-1 was overexpressed in highly metastatic B16F10 cells as compared to poorly metastatic B16F1 cells. Moreover, B16F10 cells grown in sphere conditions to enrich for cancer stem cells (CSC) progressively upregulated cripto1 expression. Vaccination of C57Bl/6 mice with a DNA vaccine encoding mouse Cripto-1 elicited a readily detectable/strong cytotoxic CD8(+) T cell response specific for a H-2 Kb-restricted epitope identified based on its ability to bind H-2(b) molecules. Remarkably, Cripto-1 vaccination elicited a protective response against lung metastasis and subcutaneous challenges with highly metastatic B16F10 melanoma cells. Our data indicate that vaccination against Cripto-1 represents a novel strategy to be tested in the clinic. PMID:27467944

  5. Th1-mediated immunity against Helicobacter pylori can compensate for lack of Th17 cells and can protect mice in the absence of immunization.

    PubMed

    Ding, Hua; Nedrud, John G; Blanchard, Thomas G; Zagorski, Brandon M; Li, Guanghui; Shiu, Jessica; Xu, Jinghua; Czinn, Steven J

    2013-01-01

    Helicobacter pylori (H. pylori) infection can be significantly reduced by immunization in mice. Th17 cells play an essential role in the protective immune response. Th1 immunity has also been demonstrated to play a role in the protective immune response and can compensate in the absence of IL-17. To further address the potential of Th1 immunity, we investigated the efficacy of immunization in mice deficient in IL-23p19, a cytokine that promotes Th17 cell development. We also examined the course of Helicobacter infection in unimmunized mice treated with Th1 promoting cytokine IL-12. C57BL/6, IL-12 p35 KO, and IL-23 p19 KO mice were immunized and challenged with H. pylori. Protective immunity was evaluated by CFU determination and QPCR on gastric biopsies. Gastric and splenic IL-17 and IFNγ levels were determined by PCR or by ELISA. Balb/c mice were infected with H. felis and treated with IL-12 therapy and the resulting gastric bacterial load and inflammatory response were assessed by histologic evaluation. Vaccine induced reductions in bacterial load that were comparable to wild type mice were observed in both IL-12 p35 and IL-23 p19 KO mice. In the absence of IL-23 p19, IL-17 levels remained low but IFNγ levels increased significantly in both immunized challenged and unimmunized/challenged mice. Additionally, treatment of H. felis-infected Balb/c mice with IL-12 resulted in increased gastric inflammation and the eradication of bacteria in most mice. These data suggest that Th1 immunity can compensate for the lack of IL-23 mediated Th17 responses, and that protective Th1 immunity can be induced in the absence of immunization through cytokine therapy of the infected host.

  6. Active Immunity Induced by Passive IgG Post-Exposure Protection against Ricin

    PubMed Central

    Hu, Charles Chen; Yin, Junfei; Chau, Damon; Cherwonogrodzky, John W.; Hu, Wei-Gang

    2014-01-01

    Therapeutic antibodies can confer an instant protection against biothreat agents when administered. In this study, intact IgG and F(ab’)2 from goat anti-ricin hyperimmune sera were compared for the protection against lethal ricin mediated intoxication. Similar ricin-binding affinities and neutralizing activities in vitro were observed between IgG and F(ab’)2 when compared at the same molar concentration. In a murine ricin intoxication model, both IgG and F(ab’)2 could rescue 100% of the mice by one dose (3 nmol) administration of antibodies 1 hour after 5 × LD50 ricin challenge. Nine days later, when the rescued mice received a second ricin challenge (5 × LD50), only the IgG-treated mice survived; the F(ab’)2-treated mice did not. The experimental design excluded the possibility of residual goat IgG responsible for the protection against the second ricin challenge. Results confirmed that the active immunity against ricin in mice was induced quickly following the passive delivery of a single dose of goat IgG post-exposure. Furthermore, it was demonstrated that the induced active immunity against ricin in mice lasted at least 5 months. Therefore, passive IgG therapy not only provides immediate protection to the victim after ricin exposure, but also elicits an active immunity against ricin that subsequently results in long term protection. PMID:24451844

  7. Immunization with DNA vaccines encoding glycoprotein D or glycoprotein B, alone or in combination, induces protective immunity in animal models of herpes simplex virus-2 disease.

    PubMed

    McClements, W L; Armstrong, M E; Keys, R D; Liu, M A

    1996-10-15

    DNA vaccines expressing herpes simplex virus type 2 (HSV-2) full-length glycoprotein D (gD), or a truncated form of HSV-2 glycoprotein B (gB) were evaluated for protective efficacy in two experimental models of HSV-2 infection. Intramuscular (i.m.) injection of mice showed that each construction induced neutralizing serum antibodies and protected the mice from lethal HSV-2 infection. Dose-titration studies showed that low doses (< or = 1 microgram) of either DNA construction induced protective immunity, and that a single immunization with the gD construction was effective. The two DNAs were then tested in a low-dosage combination in guinea pigs. Immune sera from DNA-injected animals had antibodies to both gD and gB, and virus neutralizing activity. When challenged by vaginal infection with HSV-2, the DNA-immunized animals were significantly protected from primary genital disease.

  8. Conserved epitopes of influenza A virus inducing protective immunity and their prospects for universal vaccine development.

    PubMed

    Staneková, Zuzana; Varečková, Eva

    2010-11-30

    Influenza A viruses belong to the best studied viruses, however no effective prevention against influenza infection has been developed. The emerging of still new escape variants of influenza A viruses causing epidemics and periodic worldwide pandemics represents a threat for human population. Therefore, current, hot task of influenza virus research is to look for a way how to get us closer to a universal vaccine. Combination of chosen conserved antigens inducing cross-protective antibody response with epitopes activating also cross-protective cytotoxic T-cells would offer an attractive strategy for improving protection against drift variants of seasonal influenza viruses and reduces the impact of future pandemic strains. Antigenically conserved fusion-active subunit of hemagglutinin (HA2 gp) and ectodomain of matrix protein 2 (eM2) are promising candidates for preparation of broadly protective HA2- or eM2-based vaccine that may aid in pandemic preparedness. Overall protective effect could be achieved by contribution of epitopes recognized by cytotoxic T-lymphocytes (CTL) that have been studied extensively to reach much broader control of influenza infection. In this review we present the state-of-art in this field. We describe known adaptive immune mechanisms mediated by influenza specific B- and T-cells involved in the anti-influenza immune defense together with the contribution of innate immunity. We discuss the mechanisms of neutralization of influenza infection mediated by antibodies, the role of CTL in viral elimination and new approaches to develop epitope based vaccine inducing cross-protective influenza virus-specific immune response.

  9. OmpW is a potential target for eliciting protective immunity against Acinetobacter baumannii infections.

    PubMed

    Huang, Weiwei; Wang, Shijie; Yao, Yufeng; Xia, Ye; Yang, Xu; Long, Qiong; Sun, Wenjia; Liu, Cunbao; Li, Yang; Ma, Yanbing

    2015-08-26

    Acinetobacter baumannii (A. baumannii) is an important conditioned pathogen that causes nosocomial and community-associated infections. In this study, we sought to investigate whether outer membrane protein W (OmpW) is a potential target for eliciting protective immunity against A. baumannii infections. Mice immunized with the fusion protein thioredoxin-OmpW generated strong OmpW-specific IgG responses. In a sepsis model, both active and passive immunizations against OmpW effectively protected mice from A. baumannii infections. This protection was demonstrated by a significantly improved survival rate, reduced bacterial burdens within organs, and the suppressed accumulation of inflammatory cytokines and chemokines in sera. Opsonophagocytic assays with murine macrophage RAW264.7 cells indicated that the bactericidal effects of the antisera derived from the immunized mice are mediated synergistically by specific antibodies and complement components. The antisera presented significant opsonophagocytic activities against homologous strains and clonally distinct clinical isolates in vitro. Protein data analysis showed that the sequence of OmpW, which has a molecule length of 183 amino acids, is more than 91% conserved in reported A. baumannii strains. In conclusion, we identified OmpW as a highly immunogenic and conserved protein as a valuable antigen candidate for the development of an effective vaccine or the preparation of antisera to control A. baumannii infections.

  10. Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

    PubMed Central

    Sepúlveda, Dagoberto; Lorenzen, Niels

    2016-01-01

    DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms. PMID:27054895

  11. Tetanus vaccination with a dissolving microneedle patch confers protective immune responses in pregnancy.

    PubMed

    Esser, E Stein; Romanyuk, AndreyA; Vassilieva, Elena V; Jacob, Joshy; Prausnitz, Mark R; Compans, Richard W; Skountzou, Ioanna

    2016-08-28

    Maternal and neonatal tetanus claim tens of thousands lives every year in developing countries, but could be prevented by hygienic practices and improved immunization of pregnant women. This study tested the hypothesis that skin vaccination can overcome the immunologically transformed state of pregnancy and enhance protective immunity to tetanus in mothers and their newborns. To achieve this goal, we developed microneedle patches (MNPs) that efficiently delivered unadjuvanted tetanus toxoid to skin of pregnant mice and demonstrated that this route induced superior immune responses in female mice conferring 100% survival to tetanus toxin challenge when compared to intramuscular vaccination. Mice born to MNP-vaccinated mothers showed detectable tetanus-specific IgG antibodies up to 12weeks of age and complete protection to tetanus toxin challenge up at 6weeks of age. In contrast, none of the 6-week old mice born to intramuscularly vaccinated mothers survived challenge. Although pregnant mice vaccinated with unadjuvanted tetanus toxoid had 30% lower IgG and IgG1 titers than mice vaccinated intramuscularly with Alum®-adjuvanted tetanus toxoid vaccine, IgG2a titers and antibody affinity maturation were similar between these groups. We conclude that skin immunization with MNPs containing unadjuvanted tetanus toxoid can confer potent protective efficacy to mothers and their offspring using a delivery method well suited for expanding vaccination coverage in developing countries. PMID:27327766

  12. Tetanus vaccination with a dissolving microneedle patch confers protective immune responses in pregnancy.

    PubMed

    Esser, E Stein; Romanyuk, AndreyA; Vassilieva, Elena V; Jacob, Joshy; Prausnitz, Mark R; Compans, Richard W; Skountzou, Ioanna

    2016-08-28

    Maternal and neonatal tetanus claim tens of thousands lives every year in developing countries, but could be prevented by hygienic practices and improved immunization of pregnant women. This study tested the hypothesis that skin vaccination can overcome the immunologically transformed state of pregnancy and enhance protective immunity to tetanus in mothers and their newborns. To achieve this goal, we developed microneedle patches (MNPs) that efficiently delivered unadjuvanted tetanus toxoid to skin of pregnant mice and demonstrated that this route induced superior immune responses in female mice conferring 100% survival to tetanus toxin challenge when compared to intramuscular vaccination. Mice born to MNP-vaccinated mothers showed detectable tetanus-specific IgG antibodies up to 12weeks of age and complete protection to tetanus toxin challenge up at 6weeks of age. In contrast, none of the 6-week old mice born to intramuscularly vaccinated mothers survived challenge. Although pregnant mice vaccinated with unadjuvanted tetanus toxoid had 30% lower IgG and IgG1 titers than mice vaccinated intramuscularly with Alum®-adjuvanted tetanus toxoid vaccine, IgG2a titers and antibody affinity maturation were similar between these groups. We conclude that skin immunization with MNPs containing unadjuvanted tetanus toxoid can confer potent protective efficacy to mothers and their offspring using a delivery method well suited for expanding vaccination coverage in developing countries.

  13. Can VHS Virus Bypass the Protective Immunity Induced by DNA Vaccination in Rainbow Trout?

    PubMed

    Sepúlveda, Dagoberto; Lorenzen, Niels

    2016-01-01

    DNA vaccines encoding viral glycoproteins have been very successful for induction of protective immunity against diseases caused by rhabdoviruses in cultured fish species. However, the vaccine concept is based on a single viral gene and since RNA viruses are known to possess high variability and adaptation capacity, this work aimed at evaluating whether viral haemorrhagic septicaemia virus (VHSV), an RNA virus and member of Rhabdoviridae family, was able to evade the protective immune response induced by the DNA vaccination of rainbow trout. The experiments comprised repeated passages of a highly pathogenic VHSV isolate in a fish cell line in the presence of neutralizing fish serum (in vitro approach), and in rainbow trout immunized with the VHS DNA vaccine (in vivo approach). For the in vitro approach, the virus collected from the last passage (passaged virus) was as sensitive as the parental virus to serum neutralization, suggesting that the passaging did not promote the selection of virus populations able to bypass the neutralization by serum antibodies. Also, in the in vivo approach, where virus was passaged several times in vaccinated fish, no increased virulence nor increased persistence in vaccinated fish was observed in comparison with the parental virus. However, some of the vaccinated fish did get infected and could transmit the infection to naïve cohabitant fish. The results demonstrated that the DNA vaccine induced a robust protection, but also that the immunity was non-sterile. It is consequently important not to consider vaccinated fish as virus free in veterinary terms.

  14. Protective immunity induced by tumor vaccines requires interaction between CD40 and its ligand, CD154.

    PubMed

    Mackey, M F; Gunn, J R; Ting, P P; Kikutani, H; Dranoff, G; Noelle, R J; Barth, R J

    1997-07-01

    Interactions between CD40 and its ligand, CD154 (CD40L, gp39), have been shown to play a central role in the regulation of humoral immunity. Recent evidence suggests that this ligand-receptor pair also plays an important role in the induction of cell-mediated immune responses, including those directed against viral pathogens, intracellular parasites, and alloantigens. The contribution of this ligand-receptor pair to the development of protective immunity against syngeneic tumors was evaluated by blocking the in vivo function of CD154 or by studying tumor resistance in mice genetically deficient in CD40 expression (CD40-/-). In the former case, anti-CD154 monoclonal antibody treatment inhibited the generation of protective immune responses after the administration of three potent tumor vaccines: irradiated MCA 105, MCA 105 admixed with Corynebacterium parvum adjuvant, and irradiated B16 melanoma cells transduced with the gene for granulocyte macrophage colony-stimulating factor. Confirmation of the role of CD40/CD154 interactions in tumor immunity was provided by the overt tumor susceptibility in CD40-deficient mice as compared to that in CD40+/+ mice. In this case, wild-type but not CD40-deficient mice could be readily protected against live TS/A tumor challenge by preimmunization with TS/A admixed with C. parvum. These findings suggest a critical role for CD40/CD154 interactions in the induction of cellular immunity by tumor vaccines and may have important implications for future approaches to cell-based cancer therapies. PMID:9205055

  15. Glutamine and Leucine Provide Enhanced Protective Immunity Against Mucosal Infection with Herpes Simplex Virus Type 1

    PubMed Central

    Uyangaa, Erdenebileg; Lee, Hern-Ku

    2012-01-01

    Besides their role as building blocks of protein, there are growing evidences that some amino acids have roles in regulating key metabolic pathways that are necessary for maintenance, growth, reproduction, and immunity. Here, we evaluated the modulatory functions of several amino acids in protective immunity against mucosal infection of herpes simplex virus type 1 (HSV-1). We found that glutamine (Gln) and leucine (Leu) showed enhanced protective immunity to HSV-1 mucosal infection when two administration of Gln and single administration of Leu per day, but not when administered in combinations. Ameliorated clinical signs of HSV-1 challenged mice by the intraperitoneal administration of Gln and Leu were closely associated with viral burden and IFN-γ production in the vaginal tract at 2 and 4 days post-infection. In addition, the enhanced production of vaginal IFN-γ appeared to be caused by NK and HSV-1 antigen-specific Th1-type CD4+ T cells recruited into vaginal tract of mice treated with Gln and Leu, which indicates that IFN-γ, produced by NK and Th1-type CD4+ T cells, may be critical to control the outcome of diseases caused by HSV-1 mucosal infection. Collectively, our results indicate that intraperitoneal administration of Gln and Leu following HSV-1 mucosal infection could provide beneficial effects for the modulation of protective immunity, but dosage and frequency of administration should be carefully considered, because higher frequency and overdose of Gln and Leu, or their combined treatment, showed detrimental effects to protective immunity. PMID:23213313

  16. Oral immunization with a live recombinant attenuated Salmonella typhimurium protects mice against Toxoplasma gondii.

    PubMed

    Cong, H; Gu, Q M; Jiang, Y; He, S Y; Zhou, H Y; Yang, T T; Li, Y; Zhao, Q L

    2005-01-01

    The natural site of infection for T. gondii is the mucosal surface of the intestine, so the protective immunity obtained after natural infection with T. gondii points to the importance of developing a vaccine that stimulates mucosal defences. In this study, an aroA- and aroD- attenuated strain of Salmonella typhimurium (BRD509) has been used to deliver the recombinant eukaryotic plasmid pSAG(1-2)/CTA2/B expressing a multi-antigenic gene encoding SAG1 and SAG2 of T. gondii linked to A2/B subunits of cholera toxin as a candidate oral T. gondii vaccine. Immunoblot analysis showed compound gene expression in HeLa cells in vitro and intragastric immunization of mice with the recombinant salmonella resulted in the induction of humoral and Th1 type cellular immune responses and afforded protection against RH strain T. gondii challenge. Anti-T. gondii IgG values increased markedly in the BRD509/pSAG(1-2)-CTA2/B immunized group; these values were significantly higher than those in the negative controls (P = 0.008). With CTA2/B genetic adjuvant, the T. gondii-specific response was predominantly Th1, indicating that the CTA(2)/B genetic adjuvant was able to overcome the strong Th2-bias of the antigen (IgG2a > IgG1). Antigen-specific T cell proliferative responses and CTL activity were significantly enhanced when cholera toxin CTA2/B genetic adjuvant was used (P = 0.009; P = 0.006). Culture supernatants from antigen-stimulated splenocytes from mice in these groups were also examined by ELISA for Th1- and Th2-type cytokines; mean IFN-gamma levels produced after oral immunization with BRD509/pSAG(1-2)-CTA2/B were about nine-fold higher than after immunization with BRD509/pSAG(1-2) (P = 0.007). On the other hand, the levels of IL-4 were low for all groups and no increase was seen in the presence of CTA2/B genetic adjuvant. When the immunized mice were intraperitoneally challenged with 10(3) tachyzoites of the highly virulent RH strain, the survival time of the mice immunized with

  17. Prenatal cadmium exposure produces persistent changes to thymus and spleen cell phenotypic repertoire as well as the acquired immune response

    SciTech Connect

    Holásková, Ida; Elliott, Meenal; Hanson, Miranda L.; Schafer, Rosana; Barnett, John B.

    2012-12-01

    Cadmium (Cd) is a common environmental contaminant. Adult exposure to Cd alters the immune system, however, there are limited studies on the effects of prenatal exposure to Cd. Pregnant C57Bl/6 mice were exposed to an environmentally relevant dose of CdCl{sub 2} (10 ppm) and the effects on the immune system of the offspring were assessed at 20 weeks of age. Prenatal Cd exposure caused an increase in the percent of CD4{sup −}CD8{sup −}CD44{sup +}CD25{sup −} (DN1) thymocytes in both sexes and a decrease in the percent of CD4{sup −}CD8{sup −}CD44{sup −}CD25{sup +} (DN3) thymocytes in females. Females had an increase in the percent of splenic CD4{sup +} T cells, CD8{sup +} T cells, and CD45R/B220{sup +} B cells and a decrease in the percent of NK cells and granulocytes (Gr-1{sup +}). Males had an increase in the percent of splenic CD4{sup +} T cells and CD45R/B220{sup +} B cells and a decrease in the percent of CD8{sup +} T cells, NK cells, and granulocytes. The percentage of neutrophils and myeloid-derived suppressor cells were reduced in both sexes. The percent of splenic nTreg cells was decreased in all Cd-exposed offspring. Cd-exposed offspring were immunized with a streptococcal vaccine and the antibody response was determined. PC-specific serum antibody titers were decreased in Cd exposed female offspring but increased in the males. PspA-specific serum IgG titers were increased in both females and males compared to control animals. Females had a decrease in PspA-specific serum IgM antibody titers. Females and males had a decrease in the number of splenic anti-PspA antibody-secreting cells when standardized to the number of B cells. These findings demonstrate that very low levels of Cd exposure during gestation can result in long term sex-specific alterations on the immune system of the offspring. -- Highlights: ► Prenatal exposure to cadmium alters the immune system of 20 week old offspring. ► The percentage of DN1 and DN3 thymocytes was changed

  18. Dietary selenium protect against redox-mediated immune suppression induced by methylmercury exposure.

    PubMed

    Li, Xuan; Yin, Daqiang; Yin, Jiaoyang; Chen, Qiqing; Wang, Rui

    2014-10-01

    The antagonism between selenium (Se) and mercury (Hg) has been widely recognized, however, the protective role of Se against methylmercury (MeHg) induced immunotoxicity and the underlying mechanism is still unclear. In the current study, MeHg exposure (0.01 mM via drinking water) significantly inhibited the lymphoproliferation and NK cells functions of the female Balb/c mice, while dietary Se supplementation (as Se-rich yeast) partly or fully recovered the observed immunotoxicity, indicating the protective role of Se against MeHg-induced immune suppression in mice. Besides, MeHg exposure promoted the generation of the reactive oxygen species (ROS), reduced the levels of nonenzymic and enzymic antioxidants in target organs, while dietary Se administration significantly diminished the MeHg-induced oxidative stress and subsequent cellular dysfunctions (lipid peroxidation and protein oxidation). Two possible mechanisms of Se's protective effects were further revealed. Firstly, the reduction of mercury concentrations (less than 25%, modulated by Se supplementation) in the target organs might contribute, but not fully explain the alleviated immune suppression. Secondly and more importantly, Se could help to maintain/or elevate the activities of several key antioxidants, therefore protect the immune cells against MeHg-induced oxidative damage.

  19. Plasmepsin 4-Deficient Plasmodium berghei Are Virulence Attenuated and Induce Protective Immunity against Experimental Malaria

    PubMed Central

    Spaccapelo, Roberta; Janse, Chris J.; Caterbi, Sara; Franke-Fayard, Blandine; Bonilla, J. Alfredo; Syphard, Luke M.; Di Cristina, Manlio; Dottorini, Tania; Savarino, Andrea; Cassone, Antonio; Bistoni, Francesco; Waters, Andrew P.; Dame, John B.; Crisanti, Andrea

    2010-01-01

    Plasmodium parasites lacking plasmepsin 4 (PM4), an aspartic protease that functions in the lysosomal compartment and contributes to hemoglobin digestion, have only a modest decrease in the asexual blood-stage growth rate; however, PM4 deficiency in the rodent malaria parasite Plasmodium berghei results in significantly less virulence than that for the parental parasite. P. berghei Δpm4 parasites failed to induce experimental cerebral malaria (ECM) in ECM-susceptible mice, and ECM-resistant mice were able to clear infections. Furthermore, after a single infection, all convalescent mice were protected against subsequent parasite challenge for at least 1 year. Real-time in vivo parasite imaging and splenectomy experiments demonstrated that protective immunity acted through antibody-mediated parasite clearance in the spleen. This work demonstrates, for the first time, that a single Plasmodium gene disruption can generate virulence-attenuated parasites that do not induce cerebral complications and, moreover, are able to stimulate strong protective immunity against subsequent challenge with wild-type parasites. Parasite blood-stage attenuation should help identify protective immune responses against malaria, unravel parasite-derived factors involved in malarial pathologies, such as cerebral malaria, and potentially pave the way for blood-stage whole organism vaccines. PMID:20019192

  20. Sterile Protective Immunity to Malaria is Associated with a Panel of Novel P. falciparum Antigens*

    PubMed Central

    Trieu, Angela; Kayala, Matthew A.; Burk, Chad; Molina, Douglas M.; Freilich, Daniel A.; Richie, Thomas L.; Baldi, Pierre; Felgner, Philip L.; Doolan, Denise L.

    2011-01-01

    The development of an effective malaria vaccine remains a global public health priority. Less than 0.5% of the Plasmodium falciparum genome has been assessed as potential vaccine targets and candidate vaccines have been based almost exclusively on single antigens. It is possible that the failure to develop a malaria vaccine despite decades of effort might be attributed to this historic focus. To advance malaria vaccine development, we have fabricated protein microarrays representing 23% of the entire P. falciparum proteome and have probed these arrays with plasma from subjects with sterile protection or no protection after experimental immunization with radiation attenuated P. falciparum sporozoites. A panel of 19 pre-erythrocytic stage antigens was identified as strongly associated with sporozoite-induced protective immunity; 16 of these antigens were novel and 85% have been independently identified in sporozoite and/or liver stage proteomic or transcriptomic data sets. Reactivity to any individual antigen did not correlate with protection but there was a highly significant difference in the cumulative signal intensity between protected and not protected individuals. Functional annotation indicates that most of these signature proteins are involved in cell cycle/DNA processing and protein synthesis. In addition, 21 novel blood-stage specific antigens were identified. Our data provide the first evidence that sterile protective immunity against malaria is directed against a panel of novel P. falciparum antigens rather than one antigen in isolation. These results have important implications for vaccine development, suggesting that an efficacious malaria vaccine should be multivalent and targeted at a select panel of key antigens, many of which have not been previously characterized. PMID:21628511

  1. Antiviral Protection via RdRP-Mediated Stable Activation of Innate Immunity.

    PubMed

    Painter, Meghan M; Morrison, James H; Zoecklein, Laurie J; Rinkoski, Tommy A; Watzlawik, Jens O; Papke, Louisa M; Warrington, Arthur E; Bieber, Allan J; Matchett, William E; Turkowski, Kari L; Poeschla, Eric M; Rodriguez, Moses

    2015-12-01

    For many emerging and re-emerging infectious diseases, definitive solutions via sterilizing adaptive immunity may require years or decades to develop, if they are even possible. The innate immune system offers alternative mechanisms that do not require antigen-specific recognition or a priori knowledge of the causative agent. However, it is unclear whether effective stable innate immune system activation can be achieved without triggering harmful autoimmunity or other chronic inflammatory sequelae. Here, we show that transgenic expression of a picornavirus RNA-dependent RNA polymerase (RdRP), in the absence of other viral proteins, can profoundly reconfigure mammalian innate antiviral immunity by exposing the normally membrane-sequestered RdRP activity to sustained innate immune detection. RdRP-transgenic mice have life-long, quantitatively dramatic upregulation of 80 interferon-stimulated genes (ISGs) and show profound resistance to normally lethal viral challenge. Multiple crosses with defined knockout mice (Rag1, Mda5, Mavs, Ifnar1, Ifngr1, and Tlr3) established that the mechanism operates via MDA5 and MAVS and is fully independent of the adaptive immune system. Human cell models recapitulated the key features with striking fidelity, with the RdRP inducing an analogous ISG network and a strict block to HIV-1 infection. This RdRP-mediated antiviral mechanism does not depend on secondary structure within the RdRP mRNA but operates at the protein level and requires RdRP catalysis. Importantly, despite lifelong massive ISG elevations, RdRP mice are entirely healthy, with normal longevity. Our data reveal that a powerfully augmented MDA5-mediated activation state can be a well-tolerated mammalian innate immune system configuration. These results provide a foundation for augmenting innate immunity to achieve broad-spectrum antiviral protection. PMID:26633895

  2. Antiviral Protection via RdRP-Mediated Stable Activation of Innate Immunity.

    PubMed

    Painter, Meghan M; Morrison, James H; Zoecklein, Laurie J; Rinkoski, Tommy A; Watzlawik, Jens O; Papke, Louisa M; Warrington, Arthur E; Bieber, Allan J; Matchett, William E; Turkowski, Kari L; Poeschla, Eric M; Rodriguez, Moses

    2015-12-01

    For many emerging and re-emerging infectious diseases, definitive solutions via sterilizing adaptive immunity may require years or decades to develop, if they are even possible. The innate immune system offers alternative mechanisms that do not require antigen-specific recognition or a priori knowledge of the causative agent. However, it is unclear whether effective stable innate immune system activation can be achieved without triggering harmful autoimmunity or other chronic inflammatory sequelae. Here, we show that transgenic expression of a picornavirus RNA-dependent RNA polymerase (RdRP), in the absence of other viral proteins, can profoundly reconfigure mammalian innate antiviral immunity by exposing the normally membrane-sequestered RdRP activity to sustained innate immune detection. RdRP-transgenic mice have life-long, quantitatively dramatic upregulation of 80 interferon-stimulated genes (ISGs) and show profound resistance to normally lethal viral challenge. Multiple crosses with defined knockout mice (Rag1, Mda5, Mavs, Ifnar1, Ifngr1, and Tlr3) established that the mechanism operates via MDA5 and MAVS and is fully independent of the adaptive immune system. Human cell models recapitulated the key features with striking fidelity, with the RdRP inducing an analogous ISG network and a strict block to HIV-1 infection. This RdRP-mediated antiviral mechanism does not depend on secondary structure within the RdRP mRNA but operates at the protein level and requires RdRP catalysis. Importantly, despite lifelong massive ISG elevations, RdRP mice are entirely healthy, with normal longevity. Our data reveal that a powerfully augmented MDA5-mediated activation state can be a well-tolerated mammalian innate immune system configuration. These results provide a foundation for augmenting innate immunity to achieve broad-spectrum antiviral protection.

  3. Antiviral Protection via RdRP-Mediated Stable Activation of Innate Immunity

    PubMed Central

    Painter, Meghan M.; Morrison, James H.; Zoecklein, Laurie J.; Rinkoski, Tommy A.; Watzlawik, Jens O.; Papke, Louisa M.; Warrington, Arthur E.; Bieber, Allan J.; Matchett, William E.; Turkowski, Kari L.; Poeschla, Eric M.; Rodriguez, Moses

    2015-01-01

    For many emerging and re-emerging infectious diseases, definitive solutions via sterilizing adaptive immunity may require years or decades to develop, if they are even possible. The innate immune system offers alternative mechanisms that do not require antigen-specific recognition or a priori knowledge of the causative agent. However, it is unclear whether effective stable innate immune system activation can be achieved without triggering harmful autoimmunity or other chronic inflammatory sequelae. Here, we show that transgenic expression of a picornavirus RNA-dependent RNA polymerase (RdRP), in the absence of other viral proteins, can profoundly reconfigure mammalian innate antiviral immunity by exposing the normally membrane-sequestered RdRP activity to sustained innate immune detection. RdRP-transgenic mice have life-long, quantitatively dramatic upregulation of 80 interferon-stimulated genes (ISGs) and show profound resistance to normally lethal viral challenge. Multiple crosses with defined knockout mice (Rag1, Mda5, Mavs, Ifnar1, Ifngr1, and Tlr3) established that the mechanism operates via MDA5 and MAVS and is fully independent of the adaptive immune system. Human cell models recapitulated the key features with striking fidelity, with the RdRP inducing an analogous ISG network and a strict block to HIV-1 infection. This RdRP-mediated antiviral mechanism does not depend on secondary structure within the RdRP mRNA but operates at the protein level and requires RdRP catalysis. Importantly, despite lifelong massive ISG elevations, RdRP mice are entirely healthy, with normal longevity. Our data reveal that a powerfully augmented MDA5-mediated activation state can be a well-tolerated mammalian innate immune system configuration. These results provide a foundation for augmenting innate immunity to achieve broad-spectrum antiviral protection. PMID:26633895

  4. Immunization with Eimeria ninakohlyakimovae-live attenuated oocysts protect goat kids from clinical coccidiosis.

    PubMed

    Ruiz, Antonio; Muñoz, María Carmen; Molina, José Manuel; Hermosilla, Carlos; Andrada, Marisa; Lara, Pedro; Bordón, Elisa; Pérez, Davinia; López, Adassa María; Matos, Lorena; Guedes, Aránzazu Carmen; Falcón, Soraya; Falcón, Yaiza; Martín, Sergio; Taubert, Anja

    2014-01-17

    Caprine coccidiosis, affecting mainly young goat kids around the weaning period, is worldwide the most important disease in the goat industry. Control of caprine coccidiosis is increasingly hampered by resistances developed against coccidiostatic drugs leading to an enhanced need for anticoccidial vaccines. In the current study we conducted an oral immunization trial with live attenuated sporulated Eimeria ninakohlyakimovae oocysts. Sporulated E. ninakohlyakimovae oocysts were attenuated by X-irradiation technique. The experimental design included a total of 18 goat kids divided into the following groups: (i) animals immunized with attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-irradiated homologous oocysts (group 1); (ii) animals infected with non-attenuated E. ninakohlyakimovae oocysts at 5 weeks of age and challenged 3 weeks later with non-attenuated homologous oocysts (group 2); (iii) animals primary-infected with untreated E. ninakohlyakimovae oocysts at 8 weeks of age (control of the challenge infection, group 3); (iv) non-infected control animals (group 4). Goat kids immunized with live attenuated E. ninakohlyakimovae oocysts (group 1) excreted significantly less oocysts in the faeces (95.3% reduction) than kids infected with non-attenuated ones (group 2). Furthermore, immunization with live but attenuated oocysts resulted in ameliorated clinical coccidiosis compared to goat kids infected with untreated oocysts (group 2) and resulted in equally reduced signs of coccidiosis after challenge infection compared to acquired immunity driven by non-attenuated oocysts. Overall, the present study demonstrates for the first time that live attenuated E. ninakohlyakimovae oocysts orally administered showed almost no pathogenicity but enough immunogenicity in terms of immunoprotection. Importantly, vaccinated animals still shed low amounts of oocysts, guaranteeing environmental contamination and consecutive booster

  5. Carbohydrates in plant immunity and plant protection: roles and potential application as foliar sprays

    PubMed Central

    Trouvelot, Sophie; Héloir, Marie-Claire; Poinssot, Benoît; Gauthier, Adrien; Paris, Franck; Guillier, Christelle; Combier, Maud; Trdá, Lucie; Daire, Xavier; Adrian, Marielle

    2014-01-01

    Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of “PAMP, MAMP, and DAMP (Pathogen-, Microbe-, Damage-Associated Molecular Patterns) type” oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure/activity relationships of these compounds. The role of sugars as signaling molecules, especially in plant microbe interactions, is also presented. Secondly, the potentialities and limits of foliar sprays of carbohydrates to stimulate plant immunity for crop protection against diseases are discussed, with focus on the roles of the leaf cuticle and phyllosphere microflora. PMID:25408694

  6. Transcutaneous immunization using a dissolving microneedle array protects against tetanus, diphtheria, malaria, and influenza.

    PubMed

    Matsuo, Kazuhiko; Hirobe, Sachiko; Yokota, Yayoi; Ayabe, Yurika; Seto, Masashi; Quan, Ying-Shu; Kamiyama, Fumio; Tougan, Takahiro; Horii, Toshihiro; Mukai, Yohei; Okada, Naoki; Nakagawa, Shinsaku

    2012-06-28

    Transcutaneous immunization (TCI) is an attractive alternative vaccination route compared to the commonly used injection systems. We previously developed a dissolving microneedle array for use as a TCI device, and reported that TCI with the dissolving microneedle array induced an immune response against model antigens. In the present study, we investigated the vaccination efficacy against tetanus and diphtheria, malaria, and influenza using this vaccination system. Our TCI system induced substantial increases in toxoid-specific IgG levels and toxin-neutralizing antibody titer and induced the production of anti-SE36 IgG, which could bind to malaria parasite. On influenza HA vaccination, robust antibody production was elicited in mice that provided complete protection against a subsequent influenza virus challenge. These findings demonstrate that TCI using a dissolving microneedle array can elicit large immune responses against infectious diseases. Based on these results, we are now preparing translational research for human clinical trials. PMID:22516091

  7. Lack of effect of Candida albicans mannan on development of protective immune responses in experimental murine candidiasis.

    PubMed

    Garner, R E; Domer, J E

    1994-02-01

    Candida albicans mannoprotein (MAN) administered to mice before or during immunization with viable C. albicans downregulates MAN-specific delayed hypersensitivity. In the experiments reported here we determined the effect of MAN downregulation on protective immunity in minimally immunized mice, i.e., mice exposed to C. albicans either intradermally or intragastrically, and in maximally immunized mice, i.e., mice immunized by a combination of intradermal and intragastric exposure, in experimental systemic candidiasis. MAN suppression did not induce statistically significant alterations in the protective responses in experimental candidiasis, although 8 of 12 groups of mice treated with MAN had fewer CFU of C. albicans in their kidneys than their non-MAN-treated counterparts. The results emphasize the lack of correlation of delayed hypersensitivity with protection in candidiasis and suggest that MAN may contain epitopes involved in the protective response.

  8. Cysticercosis vaccine: cross protecting immunity with T. solium antigens against experimental murine T. crassiceps cysticercosis.

    PubMed

    Sciutto, E; Fragoso, G; Trueba, L; Lemus, D; Montoya, R M; Diaz, M L; Govezensky, T; Lomeli, C; Tapia, G; Larralde, C

    1990-11-01

    Vaccination of mice with an antigen extract from Taenia solium cysticerci induced protection against challenge with T. crassiceps cysticerci as successfully as did antigen extracts from T. crassiceps. Vaccination was more effective in male than in female mice and in the resistant strain (BALB/B) more so than in the susceptible strain (BALB/c). While only the resistant strain was completely protected by vaccination, the parasite load of the susceptible strain was significantly reduced by vaccination. Cross immunity between the human and murine parasites establishes murine T. crassiceps cysticercosis as a convenient laboratory model in which to test promising T. solium antigens aimed at vaccine development against T. solium cysticercosis. Further, results point to strong interactions of the immune system with sexual and histocompatibility factors in the host's dealing with cysticercosis.

  9. A protective role of murine langerin+ cells in immune responses to cutaneous vaccination with microneedle patches

    PubMed Central

    Pulit-Penaloza, Joanna A.; Esser, E. Stein; Vassilieva, Elena V.; Lee, Jeong Woo; Taherbhai, Misha T.; Pollack, Brian P.; Prausnitz, Mark R.; Compans, Richard W.; Skountzou, Ioanna

    2014-01-01

    Cutaneous vaccination with microneedle patches offers several advantages over more frequently used approaches for vaccine delivery, including improved protective immunity. However, the involvement of specific APC subsets and their contribution to the induction of immunity following cutaneous vaccine delivery is not well understood. A better understanding of the functions of individual APC subsets in the skin will allow us to target specific skin cell populations in order to further enhance vaccine efficacy. Here we use a Langerin-EGFP-DTR knock-in mouse model to determine the contribution of langerin+ subsets of skin APCs in the induction of adaptive immune responses following cutaneous microneedle delivery of influenza vaccine. Depletion of langerin+ cells prior to vaccination resulted in substantial impairment of both Th1 and Th2 responses, and decreased post-challenge survival rates, in mice vaccinated cutaneously but not in those vaccinated via the intramuscular route or in non-depleted control mice. Our results indicate that langerin+ cells contribute significantly to the induction of protective immune responses following cutaneous vaccination with a subunit influenza vaccine. PMID:25130187

  10. Poly I:C adjuvanted inactivated swine influenza vaccine induces heterologous protective immunity in pigs.

    PubMed

    Thomas, Milton; Wang, Zhao; Sreenivasan, Chithra C; Hause, Ben M; Gourapura J Renukaradhya; Li, Feng; Francis, David H; Kaushik, Radhey S; Khatri, Mahesh

    2015-01-15

    Swine influenza is widely prevalent in swine herds in North America and Europe causing enormous economic losses and a public health threat. Pigs can be infected by both avian and mammalian influenza viruses and are sources of generation of reassortant influenza viruses capable of causing pandemics in humans. Current commercial vaccines provide satisfactory immunity against homologous viruses; however, protection against heterologous viruses is not adequate. In this study, we evaluated the protective efficacy of an intranasal Poly I:C adjuvanted UV inactivated bivalent swine influenza vaccine consisting of Swine/OH/24366/07 H1N1 and Swine/CO/99 H3N2, referred as PAV, in maternal antibody positive pigs against an antigenic variant and a heterologous swine influenza virus challenge. Groups of three-week-old commercial-grade pigs were immunized intranasally with PAV or a commercial vaccine (CV) twice at 2 weeks intervals. Three weeks after the second immunization, pigs were challenged with the antigenic variant Swine/MN/08 H1N1 (MN08) and the heterologous Swine/NC/10 H1N2 (NC10) influenza virus. Antibodies in serum and respiratory tract, lung lesions, virus shedding in nasal secretions and virus load in lungs were assessed. Intranasal administration of PAV induced challenge viruses specific-hemagglutination inhibition- and IgG antibodies in the serum and IgA and IgG antibodies in the respiratory tract. Importantly, intranasal administration of PAV provided protection against the antigenic variant MN08 and the heterologous NC10 swine influenza viruses as evidenced by significant reductions in lung virus load, gross lung lesions and significantly reduced shedding of challenge viruses in nasal secretions. These results indicate that Poly I:C or its homologues may be effective as vaccine adjuvants capable of generating cross-protective immunity against antigenic variants/heterologous swine influenza viruses in pigs.

  11. Salmonella enterica Serovar Typhimurium Lacking hfq Gene Confers Protective Immunity against Murine Typhoid

    PubMed Central

    Lahiri, Amit; Joy, Omana; Chakravortty, Dipshikha

    2011-01-01

    Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate. PMID:21347426

  12. Phi ({Phi}) and psi ({Psi}) angles involved in malarial peptide bonds determine sterile protective immunity

    SciTech Connect

    Patarroyo, Manuel E.; Moreno-Vranich, Armando; Bermudez, Adriana

    2012-12-07

    Highlights: Black-Right-Pointing-Pointer Phi ({Phi}) and psi ({Psi}) angles determine sterile protective immunity. Black-Right-Pointing-Pointer Modified peptide's tendency to assume a regular conformation related to a PPII{sub L}. Black-Right-Pointing-Pointer Structural modifications in mHABPs induce Ab and protective immunity. Black-Right-Pointing-Pointer mHABP backbone atom's interaction with HLA-DR{beta}1{sup Asterisk-Operator} is stabilised by H-bonds. -- Abstract: Modified HABP (mHABP) regions interacting with HLA-DR{beta}1{sup Asterisk-Operator} molecules have a more restricted conformation and/or sequence than other mHABPs which do not fit perfectly into their peptide binding regions (PBR) and do not induce an acceptable immune response due to the critical role of their {Phi} and {Psi} torsion angles. These angle's critical role was determined in such highly immunogenic, protection-inducing response against experimental malaria using the conformers (mHABPs) obtained by {sup 1}H-NMR and superimposed into HLA-DR{beta}1{sup Asterisk-Operator }-like Aotus monkey molecules; their phi ({Phi}) and psi ({Psi}) angles were measured and the H-bond formation between these molecules was evaluated. The aforementioned mHABP propensity to assume a regular conformation similar to a left-handed polyproline type II helix (PPII{sub L}) led to suggesting that favouring these conformations according to their amino acid sequence would lead to high antibody titre production and sterile protective immunity induction against malaria, thereby adding new principles or rules for vaccine development, malaria being one of them.

  13. Protection against henipaviruses in swine requires both, cell-mediated and humoral immune response.

    PubMed

    Pickering, Brad S; Hardham, John M; Smith, Greg; Weingartl, Eva T; Dominowski, Paul J; Foss, Dennis L; Mwangi, Duncan; Broder, Christopher C; Roth, James A; Weingartl, Hana M

    2016-09-14

    Hendra virus (HeV) and Nipah virus (NiV) are members of the genus Henipavirus, within the family Paramyxoviridae. Nipah virus has caused outbreaks of human disease in Bangladesh, Malaysia, Singapore, India and Philippines, in addition to a large outbreak in swine in Malaysia in 1998/1999. Recently, NiV was suspected to be a causative agent of an outbreak in horses in 2014 in the Philippines, while HeV has caused multiple human and equine outbreaks in Australia since 1994. A swine vaccine able to prevent shedding of infectious virus is of veterinary and human health importance, and correlates of protection against henipavirus infection in swine need to be better understood. In the present study, three groups of animals were employed. Pigs vaccinated with adjuvanted recombinant soluble HeV G protein (sGHEV) and challenged with HeV, developed antibody levels considered to be protective prior to the challenge (titers of 320). However, activation of the cell-mediated immune response was not detected, and the animals were only partially protected against challenge with 5×10(5) PFU of HeV per animal. In the second group, cross-neutralizing antibody levels against NiV in the sGHEV vaccinated animals did not reach protective levels, and with no activation of cellular immune memory, these animals were not protected against NiV. Only pigs orally infected with 5×10(4) PFU of NiV per animal were protected against nasal challenge with 5×10(5) PFU of NiV per animal. This group of pigs developed protective antibody levels, as well as cell-mediated immune memory. Peripheral blood mononuclear cells restimulated with UV-inactivated NiV upregulated IFN-gamma, IL-10 and the CD25 activation marker on CD4(+)CD8(+) T memory helper cells and to lesser extent on CD4(-)CD8(+) T cells. In conclusion, both humoral and cellular immune responses were required for protection of swine against henipaviruses. PMID:27544586

  14. Immunizations

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Immunizations KidsHealth > For Teens > Immunizations Print A A A ... That Shot? en español Las vacunas Why Are Vaccinations Important? Measles, mumps, and whooping cough may seem ...

  15. A novel fusion protein domain III-capsid from dengue-2, in a highly aggregated form, induces a functional immune response and protection in mice

    SciTech Connect

    Valdes, Iris; Bernardo, Lidice; Pavon, Alekis; Guzman, Maria G.

    2009-11-25

    Based on the immunogenicity of domain III from the Envelope protein of dengue virus as well as the proven protective capacity of the capsid antigen, we have designed a novel domain III-capsid chimeric protein with the goal of obtaining a molecule potentially able to induce both humoral and cell-mediated immunity (CMI). After expression of the recombinant gene in Escherichia coli, the domain III moiety retained its antigenicity as evaluated with anti-dengue sera. In order to explore alternatives for modulating the immunogenicity of the protein, it was mixed with oligodeoxynucleotides in order to obtain particulated aggregates and then immunologically evaluated in mice in comparison with non-aggregated controls. Although the humoral immune response induced by both forms of the protein was equivalent, the aggregated variant resulted in a much stronger CMI as measured by in vitro IFN-gamma secretion and protection experiments, mediated by CD4{sup +} and CD8{sup +} cells. The present work provides additional evidence in support for a crucial role of CMI in protection against dengue virus and describes a novel vaccine candidate against the disease based on a recombinant protein that can stimulate both arms of the acquired immune system.

  16. Genetic Regulation of Acquired Immune Responses to Antigens of Mycobacterium tuberculosis: a Study of Twins in West Africa

    PubMed Central

    Jepson, Annette; Fowler, Amanda; Banya, Winston; Singh, Mahavir; Bennett, Steve; Whittle, Hilton; Hill, Adrian V. S.

    2001-01-01

    The role of genetic factors in clinical tuberculosis is increasingly recognized; how such factors regulate the immune response to Mycobacterium tuberculosis in healthy individuals is unclear. In this study of 255 adult twin pairs residing in The Gambia, West Africa, it is apparent that memory T-cell responses to secreted mycobacterial antigens (85-kDa antigen complex, “short-term culture filtrate,” and peptides from the ESAT-6 protein), as well as to the 65-kDa heat shock protein, are subject to effective genetic regulation. The delayed hypersensitivity response to intradermal tuberculin also demonstrates significant genetic variance, while quantitative T-cell and antibody responses to the 38-kDa cell membrane protein appear to be determined largely by environmental factors. Such findings have implications for vaccine development. PMID:11349068

  17. TLR 9 involvement in early protection induced by immunization with rPb27 against Paracoccidioidomycosis.

    PubMed

    Morais, Elis Araujo; Chame, Daniela Ferreira; Melo, Eliza Mathias; de Carvalho Oliveira, Junnia Alvarenga; de Paula, Ana Cláudia Chagas; Peixoto, Andiara Cardoso; da Silva Santos, Lílian; Gomes, Dawidson Assis; Russo, Remo Castro; de Goes, Alfredo Miranda

    2016-02-01

    Paracoccidioidomycosis is caused by fungi of the Paracoccidioides genus and constitutes the most prevalent deep mycosis in Latin America. Toll-like receptors promote immune response against infectious agents. Recently, it was reported that TLR9 is crucial for mice survival during the first 48 h of P. brasiliensis infection. In this study, we used CPG oligodeoxynucleotide motif as an adjuvant with and without rPb27 to immunize mice against Paracoccidioidomycosis. CPG adjuvant induced differential recruitment of lymphocytes in the inflammatory process and a lower recruitment of neutrophils. In addition, CPG induced the production of pro-inflammatory cytokines such as IL-1β, TNF-α, IL-6 and IL-12; increased phagocytic ability and microbicidal activity by macrophages; and induced differential production of lgG2a and lgG2b, subtypes of Ig. Knockout mice for TLR9 and IL-12 showed higher fungal loads and rates of mortality compared to control mice after 30 days of infection. The association between CPG and rPb27 induced a high level of protection against Paracoccidioidomycosis after the first 30 days of infection but not at 60 days. Our findings demonstrate that TLR 9 plays a role in the protection induced by immunization with rPb27 and confirms the importance of TLR9 in the initial protection against Paracoccidioidomycosis. PMID:26597327

  18. Inducible viral receptor, A possible concept to induce viral protection in primitive immune animals.

    PubMed

    Pasharawipas, Tirasak

    2011-01-01

    A pseudolysogen (PL) is derived from the lysogenic Vibrio harveyi (VH) which is infected with the VHS1 (Vibrio harveyi Siphoviridae-like 1) bacteriophage. The lysogenic Vibrio harveyi undergoes an unequivalent division of the extra-chromosomal VHS1 phage genome and its VH host chromosome and produces a true lysogen (TL) and pseudolysogen (PL). The PL is tolerant to super-infection of VHS1, as is of the true lysogen (TL), but the PL does not contain the VHS1 phage genome while the TL does. However, the PL can become susceptible to VHS1 phage infection if the physiological state of the PL is changed. It is postulated that this is due to a phage receptor molecule which can be inducible to an on-and-off regulation influence by an alternating condition of the bacterial host cell. This characteristic of the PL leads to speculate that this phenomenon can also occur in high organisms with low immunity such as shrimp. This article proposes a hypothesis that the viral receptor molecule on the target cell can play a crucial role in which the invertebrate aquaculture animals can become tolerant to viral infection. A possible mechanism may be that the target cell disrupts the viral receptor molecule to prevent super infection. This concept can explain a mechanism for the prevention of viral infection in invertebrate animals which do not have acquired immunity in response to pathogens. It can guide us to develop a mechanism of immunity to viral infection in low-evolved-immune animals. Also, it can be an additional mechanism that exists in high immune organism, as in human for the prevention of viral infection. PMID:21711515

  19. Protective efficacy of Mycobacterium indicus pranii against tuberculosis and underlying local lung immune responses in guinea pig model.

    PubMed

    Gupta, Ankan; Ahmad, F J; Ahmad, Faiz; Gupta, U D; Natarajan, M; Katoch, V M; Bhaskar, Sangeeta

    2012-09-21

    Tuberculosis kills two million people each year. As the current vaccine BCG fails to prevent adult cases of TB, an improved vaccine and/or vaccination strategy is urgently needed to combat TB. Previously we reported the higher protective efficacy of Mycobacterium indicus pranii (MIP), formerly known as Mycobacterium w (M.w) as compared to BCG in murine model of TB. In this study we further evaluated the protective efficacy of MIP in guinea pig model of TB. Modulation of post infection immune response was analyzed in the lungs of MIP immunized and control groups. We found reduced bacterial loads, improved pathology and organized granulomatous response at different post infection time points in the MIP-immunized group as compared to the BCG-immunized group. Combined results suggest that MIP-immunization results in heightened protective Th1 response as compared to BCG group, early after infection with M.tb and a balanced Th1 versus immunosuppressive response at late chronic stage of infection. The study demonstrates the higher antigen presenting cells function both inside the granuloma as well as in the single cell suspension of the lung in the MIP-immunized group. We further demonstrate that live MIP is safe to use in vivo as we observed quick clearance of MIP from the body and no untoward reaction was found. Aerosol route of immunization provided higher protection. Further this study provides evidence that MIP-immunization gives significantly better long term protection as compared to BCG against TB.

  20. Intramuscular delivery of adenovirus serotype 5 vector expressing humanized protective antigen induces rapid protection against anthrax that may bypass intranasally originated preexisting adenovirus immunity.

    PubMed

    Wu, Shipo; Zhang, Zhe; Yu, Rui; Zhang, Jun; Liu, Ying; Song, Xiaohong; Yi, Shaoqiong; Liu, Ju; Chen, Jianqin; Yin, Ying; Xu, Junjie; Hou, Lihua; Chen, Wei

    2014-02-01

    Developing an effective anthrax vaccine that can induce a rapid and sustained immune response is a priority for the prevention of bioterrorism-associated anthrax infection. Here, we developed a recombinant replication-deficient adenovirus serotype 5-based vaccine expressing the humanized protective antigen (Ad5-PAopt). A single intramuscular injection of Ad5-PAopt resulted in rapid and robust humoral and cellular immune responses in Fisher 344 rats. Animals intramuscularly inoculated with a single dose of 10⁸ infectious units of Ad5-PAopt achieved 100% protection from challenge with 10 times the 50% lethal dose (LD₅₀) of anthrax lethal toxin 7 days after vaccination. Although preexisting intranasally induced immunity to Ad5 slightly weakened the humoral and cellular immune responses to Ad5-PAopt via intramuscular inoculation, 100% protection was achieved 15 days after vaccination in Fisher 344 rats. The protective efficacy conferred by intramuscular vaccination in the presence of preexisting intranasally induced immunity was significantly better than that of intranasal delivery of Ad5-PAopt and intramuscular injection with recombinant PA and aluminum adjuvant without preexisting immunity. As natural Ad5 infection often occurs via the mucosal route, the work here largely illuminates that intramuscular inoculation with Ad5-PAopt can overcome the negative effects of immunity induced by prior adenovirus infection and represents an efficient approach for protecting against emerging anthrax.

  1. Insights into the mechanisms of protective immunity against Cryptococcus neoformans infection using a mouse model of pulmonary cryptococcosis.

    PubMed

    Wozniak, Karen L; Ravi, Sailatha; Macias, Sandra; Young, Mattie L; Olszewski, Michal A; Steele, Chad; Wormley, Floyd L

    2009-09-03

    Cryptococcus neoformans is an opportunistic fungal pathogen that causes life-threatening pneumonia and meningoencephalitis in immune compromised individuals. Previous studies have shown that immunization of BALB/c mice with an IFN-gamma-producing C. neoformans strain, H99gamma, results in complete protection against a second pulmonary challenge with an otherwise lethal cryptococcal strain. The current study evaluated local anamnestic cell-mediated immune responses against pulmonary cryptococcosis in mice immunized with C. neoformans strain H99gamma compared to mice immunized with heat-killed C. neoformans (HKC.n.). Mice immunized with C. neoformans strain H99gamma had significantly reduced pulmonary fungal burden post-secondary challenge compared to mice immunized with HKC.n. Protection against pulmonary cryptococcosis was associated with increased pulmonary granulomatous formation and leukocyte infiltration followed by a rapid resolution of pulmonary inflammation, which protected the lungs from severe allergic bronchopulmonary mycosis (ABPM)-pathology that developed in the lungs of mice immunized with HKC.n. Pulmonary challenge of interleukin (IL)-4 receptor, IL-12p40, IL-12p35, IFN-gamma, T cell and B cell deficient mice with C. neoformans strain H99gamma demonstrated a requirement for Th1-type T cell-mediated immunity, but not B cell-mediated immunity, for the induction of H99gamma-mediated protective immune responses against pulmonary C. neoformans infection. CD4(+) T cells, CD11c(+) cells, and Gr-1(+) cells were increased in both proportion and absolute number in protected mice. In addition, significantly increased production of Th1-type/pro-inflammatory cytokines and chemokines, and conversely, reduced Th2-type cytokine production was observed in the lungs of protected mice. Interestingly, protection was not associated with increased production of cytokines IFN-gamma or TNF-alpha in lungs of protected mice. In conclusion, immunization with C. neoformans

  2. Clinical immunity to malaria.

    PubMed

    Schofield, Louis; Mueller, Ivo

    2006-03-01

    Under appropriate conditions of transmission intensity, functional immunity to malaria appears to be acquired in distinct stages. The first phase reduces the likelihood of severe or fatal disease; the second phase limits the clinical impact of 'mild' malaria; and the third provides partial but incomplete protection against pathogen burden. These findings suggest clinical immunity to mortality and morbidity is acquired earlier, with greater ease, and via distinct mechanisms as compared to anti-parasite immunity, which is more difficult to achieve, takes longer and is only ever partially efficacious. The implications of this view are significant in that current vaccination strategies aim predominantly to achieve anti-parasite immunity, although imparting clinical immunity is the public health objective. Despite enormous relevance for global public health, the mechanisms governing these processes remain obscure. Four candidate mechanisms might mediate clinical immunity, namely immunity to cytoadherence determinants, tolerance to toxins, acquired immunity to toxins, and immunoregulation. This review addresses the targets and determinants of clinical immunity, and considers the implications for vaccine development.

  3. Epidemiology of children with acquired immune deficiency syndrome (stage 3): A referral hospital-based study in Iran.

    PubMed

    Movahedi, Zahra; Mahmoudi, Shima; Pourakbari, Babak; Keshavarz Valian, Nasrin; Sabouni, Farah; Ramezani, Amitis; Bahador, Abbas; Mamishi, Setareh

    2016-01-01

    Lack of recognition of human immunodeficiency virus (HIV) infection especially in children and delayed implementation of effective control programs makes HIV infection as a major cause for concern. Information on HIV epidemiology in Iran as well as other Islamic countries is limited. The aim of our study was to describe the clinical manifestation and laboratory finding of HIV infected children who were admitted to a referral Children Medical Center (CMC) in Tehran, Iran, during 11 years from January 2002 to January 2013. This was a retrospective study carried out over a period of 11 years. The records of all patients attending to the CMC with confirmed acquired immunodeficiency syndrome (AIDS) were screened. The patients were evaluated for social circumstance, family history, age, gender, clinical, and laboratory features. Clinical data including fever, respiratory distress, diarrhea, rash, etc. as well as laboratory tests including complete blood count, serum glucose level, electrolytes, liver function test, cultures, CD4 lymphocyte count were evaluated. During the study period, 32 HIV positive children were enrolled. The majority of patients were presented with weight loss, prolonged fever, respiratory infection and chronic diarrhea. In this study, salmonella infections as well as streptococcal pneumonia and candida infections followed by, tuberculosis and Pseudomonas aeruginosa infections were the predominant opportunistic infections. Since the number of HIV-positive children has been alarmingly increasing in recent years and perinatal transmission is the most common route of HIV infection in children, essential recommendations for prenatal HIV testing as well as appropriate antiretroviral therapy by HIV infected mothers are needed.

  4. Refractory and/or Relapsing Cryptococcosis Associated with Acquired Immune Deficiency Syndrome: Clinical Features, Genotype, and Virulence Factors of Cryptococcus spp. Isolates.

    PubMed

    Nascimento, Erika; Vitali, Lucia H; Tonani, Ludmilla; Kress, Marcia R Von Zeska; Takayanagui, Osvaldo M; Martinez, Roberto

    2016-05-01

    Refractory and relapsing crytocococcosis in acquired immune deficiency syndrome (AIDS) patients have a poor prognosis. The risk factors for this complicated infection course were evaluated by comparing refractory and/or relapsing cryptococcosis in human immunodeficiency virus-coinfected patients (cohort 1) with another group of AIDS patients who adequately responded to antifungals (cohort 2). Except for one isolate of Cryptococcus gattii from a cohort 2 case, all other isolates were identified as Cryptococcus neoformans var. grubii, sex type α, genotype VNI, including Cryptococcus reisolated from the relapse or in the refractory state. No differences were observed with respect to Cryptococcus capsule size and in the melanin and phospholipase production. The cohort 1 patients presented higher prevalence of cryptococcemia, cerebral dissemination, chronic liver disease, and leucopenia, and have increased death rate. Apparently, the refractory and/or relapsing cryptococcosis in the AIDS patients were more related to the host and the extent of the infection than to the fungal characteristics. PMID:26928832

  5. Unified-planning, graded-administration, and centralized-controlling: a management modality for treating acquired immune deficiency syndrome with Chinese medicine in Henan Province of China.

    PubMed

    Xu, Li-Ran; Guo, Hui-jun; Liu, Zhi-bin; Li, Qiang; Yang, Ji-ping; He, Ying

    2015-04-01

    Henan Province in China has a major epidemic of human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). Chinese medicine (CM) has been used throughout the last decade, and a management modality was developed, which can be described by unified-planning, graded-administration, and centralized-controlling (UGC). The UGC modality has one primary concept (patient-centered medicine from CM theory), four basic foundations (classifying administrative region, characteristics of CM on disease treatment, health resource conditions, and distribution of patients living with HIV), six important relationships (the "three uniformities and three combinations," and the six relationships therein guide the treatment of AIDS with CM), and four key sections (management, operation, records, and evaluation). In this article, the authors introduce the UGC modality, which could be beneficial to developing countries or resource-limited areas for the management of chronic infectious disease. PMID:25877652

  6. Induction of antibody to asialo GM1 by spermatozoa and its occurrence in the sera of homosexual men with the acquired immune deficiency syndrome (AIDS).

    PubMed Central

    Witkin, S S; Sonnabend, J; Richards, J M; Purtilo, D T

    1983-01-01

    Compared to healthy homosexual and heterosexual men, homosexual men with acquired immune deficiency syndrome (AIDS) possessed significantly higher levels of IgG antibody to the neutral glycolipid asialo GM1 (ganglio-N-tetraosylceramide) (P less than 0.01). Of 31 homosexuals with AIDS, 36% possessed levels of this antibody that were at least two standard deviations above the mean of the healthy men. Furthermore, asialo GM1 antibody could be removed from serum by adsorption with spermatozoa. Weekly rectal insemination of male rabbits with rabbit semen also led to the appearance of antibody to asialo GM1 by 15 weeks. These results suggest that asialo GM1 is a component of ejaculated spermatozoa and demonstrate that rectal insemination by itself can lead to the production of antibodies to this glycolipid in the rabbit. In addition, asialo GM1 antibodies may be of value as a serological marker for the early detection of individuals with AIDS. PMID:6652964

  7. Unified-planning, graded-administration, and centralized-controlling: a management modality for treating acquired immune deficiency syndrome with Chinese medicine in Henan Province of China.

    PubMed

    Xu, Li-Ran; Guo, Hui-jun; Liu, Zhi-bin; Li, Qiang; Yang, Ji-ping; He, Ying

    2015-04-01

    Henan Province in China has a major epidemic of human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS). Chinese medicine (CM) has been used throughout the last decade, and a management modality was developed, which can be described by unified-planning, graded-administration, and centralized-controlling (UGC). The UGC modality has one primary concept (patient-centered medicine from CM theory), four basic foundations (classifying administrative region, characteristics of CM on disease treatment, health resource conditions, and distribution of patients living with HIV), six important relationships (the "three uniformities and three combinations," and the six relationships therein guide the treatment of AIDS with CM), and four key sections (management, operation, records, and evaluation). In this article, the authors introduce the UGC modality, which could be beneficial to developing countries or resource-limited areas for the management of chronic infectious disease.

  8. Neutrophils play an important role in protective immunity against Coxiella burnetii infection.

    PubMed

    Elliott, Alexandra; Schoenlaub, Laura; Freches, Danielle; Mitchell, William; Zhang, Guoquan

    2015-08-01

    Coxiella burnetii is an obligate intracellular Gram-negative bacterium that causes the zoonotic disease Q fever. Although Q fever is mainly transmitted by aerosol infection, study of the immune responses in the lung following pulmonary C. burnetii infection is lacking. Neutrophils are considered the first immune cell to migrate into the lung and play an important role in host defense against aerosol infection with microbial pathogens. However, the role of neutrophils in the host defense against C. burnetii infection remains unclear. To determine the role of neutrophils in protective immunity against C. burnetii infection, the RB6-8C5 antibody was used to deplete neutrophils in mice before intranasal infection with C. burnetii. The results indicated that neutrophil-depleted mice developed more severe disease than their wild-type counterparts, suggesting that neutrophils play an important role in host defense against C. burnetii pulmonary infection. We also found that neither CXC chemokine receptor 2 (CXCR2) nor interleukin-17 (IL-17) receptor (IL-17R) deficiency changed the severity of disease following intranasal C. burnetii challenge, suggesting that keratinocyte-derived chemokine and IL-17 may not play essential roles in the response to C. burnetii infection. However, significantly higher C. burnetii genome copy numbers were detected in the lungs of IL-1R(-/-) mice at 14 days postinfection. This indicates that IL-1 may be important for the clearance of C. burnetii from the lungs following intranasal infection. Our results also suggest that neutrophils are involved in protecting vaccinated mice from C. burnetii challenge-induced disease. This is the first study to demonstrate an important role for neutrophils in protective immunity against C. burnetii infection.

  9. Murine Dendritic Cells Pulsed In Vitro with Toxoplasma gondii Antigens Induce Protective Immunity In Vivo

    PubMed Central

    Bourguin, Isabelle; Moser, Muriel; Buzoni-Gatel, Dominique; Tielemans, Françoise; Bout, Daniel; Urbain, Jacques; Leo, Oberdan

    1998-01-01

    The activation of a predominant T-helper-cell subset plays a critical role in disease resolution. In the case of Toxoplasma gondii, the available evidence indicates that CD4+ protective cells belong to the Th1 subset. The aim of this study was to determine whether T. gondii antigens (in T. gondii sonicate [TSo]) presented by splenic dendritic cells (DC) were able to induce a specific immune response in vivo and to protect CBA/J mice orally challenged with T. gondii cysts. CBA/J mice immunized with TSo-pulsed DC exhibited significantly fewer cysts in their brains after oral infection with T. gondii 76K than control mice did. Protected mice developed a strong humoral response in vivo, with especially high levels of anti-TSo immunoglobulin G2a antibodies in serum. T. gondii antigens such as SAG1 (surface protein), SAG2 (surface protein), MIC1 (microneme protein), ROP2 through ROP4 (rhoptry proteins), and MIC2 (microneme protein) were recognized predominantly. Furthermore, DC loaded with TSo, which synthesized high levels of interleukin-12 (IL-12), triggered a strong cellular response in vivo, as assessed by the proliferation of lymph node cells in response to TSo restimulation in vitro. Cellular proliferation was associated with gamma interferon and IL-2 production. Taken together, these results indicate that immunization of CBA/J mice with TSo-pulsed DC can induce both humoral and Th1-like cellular immune responses and affords partial resistance against the establishment of chronic toxoplasmosis. PMID:9746591

  10. Virtual Optimization of Nasal Insulin Therapy Predicts Immunization Frequency to Be Crucial for Diabetes Protection

    PubMed Central

    Fousteri, Georgia; Chan, Jason R.; Zheng, Yanan; Whiting, Chan; Dave, Amy; Bresson, Damien; Croft, Michael; von Herrath, Matthias

    2010-01-01

    OBJECTIVE Development of antigen-specific strategies to treat or prevent type 1 diabetes has been slow and difficult because of the lack of experimental tools and defined biomarkers that account for the underlying therapeutic mechanisms. RESEARCH DESIGN AND METHODS The type 1 diabetes PhysioLab platform, a large-scale mathematical model of disease pathogenesis in the nonobese diabetic (NOD) mouse, was used to investigate the possible mechanisms underlying the efficacy of nasal insulin B:9-23 peptide therapy. The experimental aim was to evaluate the impact of dose, frequency of administration, and age at treatment on Treg induction and optimal therapeutic outcome. RESULTS In virtual NOD mice, treatment efficacy was predicted to depend primarily on the immunization frequency and stage of the disease and to a lesser extent on the dose. Whereas low-frequency immunization protected from diabetes atrributed to Treg and interleukin (IL)-10 induction in the pancreas 1–2 weeks after treatment, high-frequency immunization failed. These predictions were confirmed with wet-lab approaches, where only low-frequency immunization started at an early disease stage in the NOD mouse resulted in significant protection from diabetes by inducing IL-10 and Treg. CONCLUSIONS Here, the advantage of applying computer modeling in optimizing the therapeutic efficacy of nasal insulin immunotherapy was confirmed. In silico modeling was able to streamline the experimental design and to identify the particular time frame at which biomarkers associated with protection in live NODs were induced. These results support the development and application of humanized platforms for the design of clinical trials (i.e., for the ongoing nasal insulin prevention studies). PMID:20864513

  11. BacMam immunization partially protects pigs against sublethal challenge with African swine fever virus.

    PubMed

    Argilaguet, Jordi M; Pérez-Martín, Eva; López, Sergio; Goethe, Martin; Escribano, J M; Giesow, Katrin; Keil, Günther M; Rodríguez, Fernando

    2013-04-01

    Lack of vaccines and efficient control measures complicate the control and eradication of African swine fever (ASF). Limitations of conventional inactivated and attenuated virus-based vaccines against African swine fever virus (ASFV) highlight the need to use new technologies to develop efficient and safe vaccines against this virus. With this aim in mind, in this study we have constructed BacMam-sHAPQ, a baculovirus based vector for gene transfer into mammalian cells, expressing a fusion protein comprising three in tandem ASFV antigens: p54, p30 and the extracellular domain of the viral hemagglutinin (secretory hemagglutinin, sHA), under the control of the human cytomegalovirus immediate early promoter (CMVie). Confirming its correct in vitro expression, BacMam-sHAPQ induced specific T-cell responses directly after in vivo immunization. Conversely, no specific antibody responses were detectable prior to ASFV challenge. The protective potential of this recombinant vaccine candidate was tested by a homologous sublethal challenge with ASFV following immunization. Four out of six immunized pigs remained viremia-free after ASFV infection, while the other two pigs showed similar viremic titres to control animals. The protection afforded correlated with the presence of a large number of virus-specific IFNγ-secreting T-cells in blood at 17 days post-infection. In contrast, the specific antibody levels observed after ASFV challenge in sera from BacMam-sHAPQ immunized pigs were indistinguishable from those found in control pigs. These results highlight the importance of the cellular responses in protection against ASFV and point towards BacMam vectors as potential tools for future vaccine development.

  12. Comprehensive analysis and selection of anthrax vaccine adsorbed immune correlates of protection in rhesus macaques.

    PubMed

    Chen, Ligong; Schiffer, Jarad M; Dalton, Shannon; Sabourin, Carol L; Niemuth, Nancy A; Plikaytis, Brian D; Quinn, Conrad P

    2014-11-01

    Humoral and cell-mediated immune correlates of protection (COP) for inhalation anthrax in a rhesus macaque (Macaca mulatta) model were determined. The immunological and survival data were from 114 vaccinated and 23 control animals exposed to Bacillus anthracis spores at 12, 30, or 52 months after the first vaccination. The vaccinated animals received a 3-dose intramuscular priming series (3-i.m.) of anthrax vaccine adsorbed (AVA) (BioThrax) at 0, 1, and 6 months. The immune responses were modulated by administering a range of vaccine dilutions. Together with the vaccine dilution dose and interval between the first vaccination and challenge, each of 80 immune response variables to anthrax toxin protective antigen (PA) at every available study time point was analyzed as a potential COP by logistic regression penalized by least absolute shrinkage and selection operator (LASSO) or elastic net. The anti-PA IgG level at the last available time point before challenge (last) and lymphocyte stimulation index (SI) at months 2 and 6 were identified consistently as a COP. Anti-PA IgG levels and lethal toxin neutralization activity (TNA) at months 6 and 7 (peak) and the frequency of gamma interferon (IFN-γ)-secreting cells at month 6 also had statistically significant positive correlations with survival. The ratio of interleukin 4 (IL-4) mRNA to IFN-γ mRNA at month 6 also had a statistically significant negative correlation with survival. TNA had lower accuracy as a COP than did anti-PA IgG response. Following the 3-i.m. priming with AVA, the anti-PA IgG responses at the time of exposure or at month 7 were practicable and accurate metrics for correlating vaccine-induced immunity with protection against inhalation anthrax.

  13. Immunization of Mice with Anthrax Protective Antigen Limits Cardiotoxicity but Not Hepatotoxicity Following Lethal Toxin Challenge.

    PubMed

    Devera, T Scott; Prusator, Dawn K; Joshi, Sunil K; Ballard, Jimmy D; Lang, Mark L

    2015-06-25

    Protective immunity against anthrax is inferred from measurement of vaccine antigen-specific neutralizing antibody titers in serum samples. In animal models, in vivo challenges with toxin and/or spores can also be performed. However, neither of these approaches considers toxin-induced damage to specific organ systems. It is therefore important to determine to what extent anthrax vaccines and existing or candidate adjuvants can provide organ-specific protection against intoxication. We therefore compared the ability of Alum, CpG DNA and the CD1d ligand α-galactosylceramide (αGC) to enhance protective antigen-specific antibody titers, to protect mice against challenge with lethal toxin, and to block cardiotoxicity and hepatotoxicity. By measurement of serum cardiac Troponin I (cTnI), and hepatic alanine aminotransferase (ALT), and aspartate aminotransferase (AST), it was apparent that neither vaccine modality prevented hepatic intoxication, despite high Ab titers and ultimate survival of the subject. In contrast, cardiotoxicity was greatly diminished by prior immunization. This shows that a vaccine that confers survival following toxin exposure may still have an associated morbidity. We propose that organ-specific intoxication should be monitored routinely during research into new vaccine modalities.

  14. Short report: mode of action of protective immunity to Lyme disease spirochetes.

    PubMed

    Shih, C M; Spielman, A; Telford, S R

    1995-01-01

    To determine whether protective immunity against the agent of Lyme disease may be expressed mainly within its tick vector prior to transmission, we passively immunized mice at various intervals after infected ticks had attached, and assayed such mice for evidence of spirochetal infection by xenodiagnosis one month after challenge. Groups of CD-1 mice were intraperitoneally infused with 0.5 ml of hyperimmune rabbit or mouse serum, reagents and quantities previously determined to protect against syringe-challenge with 10(6) low-passage JD1 spirochetes 12 hr after passive transfer. Comparison groups received normal rabbit serum or saline. All mice were protected from infection when infused no more than one day after infective ticks were allowed to attach. However, if infused three or five days post-tick attachment, 60-100% of the mice became infected. All mice became persistently infected when infused with saline or normal rabbit serum. We conclude that antibody is protective against tick-transmitted spirochetal infection only when passively administered before the spirochetes are deposited in the skin of the host. Ingested antibody may destroy spirochetes or interfere with activation and replication within the tick gut, or with dissemination to the salivary glands. Lyme disease vaccines may thus be uniquely effective because of the vulnerability of the spirochetal agent within its vector.

  15. Protective immunity to Japanese encephalitis virus associated with anti-NS1 antibodies in a mouse model

    PubMed Central

    2012-01-01

    Background Japanese encephalitis virus (JEV) is a major mosquito-borne pathogen that causes viral encephalitis throughout Asia. Vaccination with an inactive JEV particle or attenuated virus is an efficient preventative measure for controlling infection. Flavivirus NS1 protein is a glycoprotein secreted during viral replication that plays multiple roles in the viral life cycle and pathogenesis. Utilizing JEV NS1 as an antigen in viral vectors induces a limited protective immune response against infection. Previous studies using E. coli-expressed JEV NS1 to immunize mice induced protection against lethal challenge; however, the protection mechanism through cellular and humoral immune responses was not described. Results JEV NS1 was expressed in and purified from Drosophila S2 cells in a native glycosylated multimeric form, which induced T-cell and antibody responses in immunized C3H/HeN mice. Mice vaccinated with 1 μg NS1 with or without water-in-oil adjuvant were partially protected against viral challenge and higher protection was observed in mice with higher antibody titers. IgG1 was preferentially elicited by an adjuvanted NS1 protein, whereas a larger load of IFN-γ was produced in splenocytes from mice immunized with aqueous NS1. Mice that passively received anti-NS1 mouse polyclonal immune sera were protected, and this phenomenon was dose-dependent, whereas protection was low or delayed after the passive transfer of anti-NS1 MAbs. Conclusion The purified NS1 subunit induced protective immunity in relation with anti-NS1 IgG1 antibodies. NS1 protein efficiently stimulated Th1-cell proliferation and IFN-γ production. Protection against lethal challenge was elicited by passive transfer of anti-NS1 antisera, suggesting that anti-NS1 antibodies play a substantial role in anti-viral immunity PMID:22828206

  16. Expression Library Immunization Can Confer Protection against Lethal Challenge with African Swine Fever Virus

    PubMed Central

    Lacasta, Anna; Ballester, María; Monteagudo, Paula L.; Rodríguez, Javier M.; Salas, María L.; Accensi, Francesc; Pina-Pedrero, Sonia; Bensaid, Albert; Argilaguet, Jordi; López-Soria, Sergio; Hutet, Evelyne; Le Potier, Marie Frédérique

    2014-01-01

    ABSTRACT African swine fever is one of the most devastating pig diseases, against which there is no vaccine available. Recent work from our laboratory has demonstrated the protective potential of DNA vaccines encoding three African swine fever viral antigens (p54, p30, and the hemagglutinin extracellular domain) fused to ubiquitin. Partial protection was afforded in the absence of detectable antibodies prior to virus challenge, and survival correlated with the presence of a large number of hemagglutinin-specific CD8+ T cells in blood. Aiming to demonstrate the presence of additional CD8+ T-cell determinants with protective potential, an expression library containing more than 4,000 individual plasmid clones was constructed, each one randomly containing a Sau3AI restriction fragment of the viral genome (p54, p30, and hemagglutinin open reading frames [ORFs] excluded) fused to ubiquitin. Immunization of farm pigs with the expression library yielded 60% protection against lethal challenge with the virulent E75 strain. These results were further confirmed by using specific-pathogen-free pigs after challenging them with 104 hemadsorbing units (HAU) of the cell culture-adapted strain E75CV1. On this occasion, 50% of the vaccinated pigs survived the lethal challenge, and 2 out of the 8 immunized pigs showed no viremia or viral excretion at any time postinfection. In all cases, protection was afforded in the absence of detectable specific antibodies prior to challenge and correlated with the detection of specific T-cell responses at the time of sacrifice. In summary, our results clearly demonstrate the presence of additional protective determinants within the African swine fever virus (ASFV) genome and open up the possibility for their future identification. IMPORTANCE African swine fever is a highly contagious disease of domestic and wild pigs that is endemic in many sub-Saharan countries, where it causes important economic losses and is currently in continuous expansion

  17. Immunogenicity and protective immunity against bubonic plague and pneumonic plague by immunization of mice with the recombinant V10 antigen, a variant of LcrV.

    PubMed

    DeBord, Kristin L; Anderson, Deborah M; Marketon, Melanie M; Overheim, Katie A; DePaolo, R William; Ciletti, Nancy A; Jabri, Bana; Schneewind, Olaf

    2006-08-01

    In contrast to Yersinia pestis LcrV, the recombinant V10 (rV10) variant (lacking residues 271 to 300) does not suppress the release of proinflammatory cytokines by immune cells. Immunization with rV10 generates robust antibody responses that protect mice against bubonic plague and pneumonic plague, suggesting that rV10 may serve as an improved plague vaccine.

  18. Short communication: Naturally sensitive Bacillus thuringiensis EG10368 produces thurincin H and acquires immunity after heterologous expression of the one-step-amplified thurincin H gene cluster.

    PubMed

    Wang, G; Manns, D C; Churey, J J; Worobo, R W

    2014-07-01

    Heterologous expression of bacteriocin genetic determinants (or operons) has long been a research interest for the functional analysis of genes involved in bacteriocin biosynthesis, regulation, modification, and immunity. Previously, construction of genomic libraries of the bacteriocin producer strains was usually required to identify new bacteriocin operons, a method that is tedious and time consuming. For the first time, we directly amplified an 8.14-kb bioinformatically identified thurincin H gene cluster using a one-step PCR method with 100% accuracy. This amplified gene cluster was cloned into plasmid pHT315, resulting in plasmid pGW139, and subsequently transformed to Bacillus thuringiensis EG10368, a strain naturally sensitive to thurincin H. Heterologous expression of the gene cluster makes the sensitive B. thuringiensis EG10368 produce thurincin H at a higher level compared with the wild-type producer, B. thuringiensis SF361. Moreover, B. thuringiensis EG10368pGW139 acquired complete immunity to thurincin H. The results indicated that one-step PCR is a promising tool to accurately amplify long bacteriocin gene clusters used in bacteriocin functional analysis studies and it is an effective way to produce bacteriocins at a higher level, without the need to clone large chromosomal fragments.

  19. Cross-clade protective immunity of H5N1 influenza vaccines in a mouse model

    PubMed Central

    Murakami, Shin; Iwasa, Ayaka; Iwatsuki-Horimoto, Kiyoko; Ito, Mutsumi; Kiso, Maki; Kida, Hiroshi; Takada, Ayato; Nidom, Chairul A.; Mai, Le Quynh; Yamada, Shinya; Imai, Hirotaka; Sakai-Tagawa, Yuko; Kawaoka, Yoshihiro; Horimoto, Taisuke

    2008-01-01

    H5N1 highly pathogenic avian influenza viruses evolved into several clades, leading to appreciably distinct antigenicities of their hemagglutinins. As such, candidate H5N1 pre-pandemic vaccines for human use should be sought. Here, to evaluate fundamental immunogenic variations between H5N1 vaccines, we prepared four inactivated H5N1 test vaccines from different phylogenetic clades (clade 1, 2.1, 2.2, and 2.3.4) in accordance with the WHO recommendation, and tested their cross-clade immunity in a mouse model by vaccination followed by challenge with heterologous virulent viruses. All H5N1 vaccines tested provided full or partial cross-clade protective immunity, except one clade 2.2-based vaccine, which did not protect mice from clade 2.3.4 virus challenge. Among the test vaccines, a clade 2.1-based vaccine possessed the broadest-spectrum cross-immunity. These results suggest that currently stockpiled pre-pandemic vaccines, especially clade 2.1-based vaccines, will likely be useful as backup vaccines in a pandemic situation, even one involving antigenic-drifted viruses. PMID:18804131

  20. Neonatal Fc receptor expression in dendritic cells mediates protective immunity against colorectal cancer.

    PubMed

    Baker, Kristi; Rath, Timo; Flak, Magdalena B; Arthur, Janelle C; Chen, Zhangguo; Glickman, Jonathan N; Zlobec, Inti; Karamitopoulou, Eva; Stachler, Matthew D; Odze, Robert D; Lencer, Wayne I; Jobin, Christian; Blumberg, Richard S

    2013-12-12

    Cancers arising in mucosal tissues account for a disproportionately large fraction of malignancies. Immunoglobulin G (IgG) and the neonatal Fc receptor for IgG (FcRn) have an important function in the mucosal immune system that we have now shown extends to the induction of CD8(+) T cell-mediated antitumor immunity. We demonstrate that FcRn within dendritic cells (DCs) was critical for homeostatic activation of mucosal CD8(+) T cells that drove protection against the development of colorectal cancers and lung metastases. FcRn-mediated tumor protection was driven by DCs activation of endogenous tumor-reactive CD8(+) T cells via the cross-presentation of IgG complexed antigens (IgG IC), as well as the induction of cytotoxicity-promoting cytokine secretion, particularly interleukin-12, both of which were independently triggered by the FcRn-IgG IC interaction in murine and human DCs. FcRn thus has a primary role within mucosal tissues in activating local immune responses that are critical for priming efficient anti-tumor immunosurveillance.

  1. Immune responses and protection in children in developing countries induced by oral vaccines.

    PubMed

    Qadri, Firdausi; Bhuiyan, Taufiqur Rahman; Sack, David A; Svennerholm, Ann-Mari

    2013-01-01

    Oral mucosal vaccines have great promise for generating protective immunity against intestinal infections for the benefit of large numbers of people especially young children. There however appears to be a caveat since these vaccines have to overcome the inbuilt resistance of mucosal surfaces and secretions to inhibit antigen stimulation and responses. Unfortunately, these vaccines are not equally immunogenic nor protective in different populations. When compared to industrialized countries, children living in developing countries appear to have lower responses, but the reasons for these lowered responses are not clearly defined. The most likely explanations relate to undernutrition, micronutrient deficiencies, microbial overload on mucosal surfaces, alteration of microbiome and microbolom and irreversible changes on the mucosa as well as maternal antibodies in serum or breast milk may alter the mucosal pathology and lower immune responses to interventions using oral vaccines. The detrimental effect of adverse environment and malnutrition may bring about irreversible changes in the mucosa of children especially in the first 1000 days of life from conception to after birth and up to two years of age. This review aims to summarize the information available on lowered immune responses to mucosal vaccines and on interventions that may help address the constraints of these vaccines when they are used for children living under the greatest stress and under harmful adverse circumstances.

  2. Electroacupuncture at Bilateral Zusanli Points (ST36) Protects Intestinal Mucosal Immune Barrier in Sepsis

    PubMed Central

    Zhu, Mei-fei; Xing, Xi; Lei, Shu; Wu, Jian-nong; Wang, Ling-cong; Huang, Li-quan; Jiang, Rong-lin

    2015-01-01

    Sepsis results in high morbidity and mortality. Immunomodulation strategies could be an adjunctive therapy to treat sepsis. Acupuncture has also been used widely for many years in China to treat sepsis. However, the underlying mechanisms are not well-defined. We demonstrated here that EA preconditioning at ST36 obviously ameliorated CLP-induced intestinal injury and high permeability and reduced the mortality of CLP-induced sepsis rats. Moreover, electroacupuncture (EA) pretreatment exerted protective effects on intestinal mucosal immune barrier by increasing the concentration of sIgA and the percentage of CD3+, γ/δ, and CD4+ T cells and the ratio of CD4+/CD8+ T cells. Although EA at ST36 treatments immediately after closing the abdomen in the CLP procedure with low-frequency or high-frequency could not reduce the mortality of CLP-induced sepsis in rats, these EA treatments could also significantly improve intestinal injury index in rats with sepsis and obviously protected intestinal mucosal immune barrier. In conclusion, our findings demonstrated that EA at ST36 could improve intestinal mucosal immune barrier in sepsis induced by CLP, while the precise mechanism underlying the effects needs to be further elucidated. PMID:26346309

  3. Drug treatment of malaria infections can reduce levels of protection transferred to offspring via maternal immunity

    PubMed Central

    Staszewski, Vincent; Reece, Sarah E.; O'Donnell, Aidan J.; Cunningham, Emma J. A.

    2012-01-01

    Maternally transferred immunity can have a fundamental effect on the ability of offspring to deal with infection. However, levels of antibodies in adults can vary both quantitatively and qualitatively between individuals and during the course of infection. How infection dynamics and their modification by drug treatment might affect the protection transferred to offspring remains poorly understood. Using the rodent malaria parasite Plasmodium chabaudi, we demonstrate that curing dams part way through infection prior to pregnancy can alter their immune response, with major consequences for offspring health and survival. In untreated maternal infections, maternally transferred protection suppressed parasitaemia and reduced pup mortality by 75 per cent compared with pups from naïve dams. However, when dams were treated with anti-malarial drugs, pups received fewer maternal antibodies, parasitaemia was only marginally suppressed, and mortality risk was 25 per cent higher than for pups from dams with full infections. We observed the same qualitative patterns across three different host strains and two parasite genotypes. This study reveals the role that within-host infection dynamics play in the fitness consequences of maternally transferred immunity. Furthermore, it highlights a potential trade-off between the health of mothers and offspring suggesting that anti-parasite treatment may significantly affect the outcome of infection in newborns. PMID:22357264

  4. The immune response against Chlamydia suis genital tract infection partially protects against re-infection.

    PubMed

    De Clercq, Evelien; Devriendt, Bert; Yin, Lizi; Chiers, Koen; Cox, Eric; Vanrompay, Daisy

    2014-09-25

    The aim of the present study was to reveal the characteristic features of genital Chlamydia suis infection and re-infection in female pigs by studying the immune response, pathological changes, replication of chlamydial bacteria in the genital tract and excretion of viable bacteria. Pigs were intravaginally infected and re-infected with C. suis strain S45, the type strain of this species. We demonstrated that S45 is pathogenic for the female urogenital tract. Chlamydia replication occurred throughout the urogenital tract, causing inflammation and pathology. Furthermore, genital infection elicited both cellular and humoral immune responses. Compared to the primo-infection of pigs with C. suis, re-infection was characterized by less severe macroscopic lesions and less chlamydial elementary bodies and inclusions in the urogenital tract. This indicates the development of a certain level of protection following the initial infection. Protective immunity against re-infection coincided with higher Chlamydia-specific IgG and IgA antibody titers in sera and vaginal secretions, higher proliferative responses of peripheral blood mononuclear cells (PBMC), higher percentages of blood B lymphocytes, monocytes and CD8⁺ T cells and upregulated production of IFN-γ and IL-10 by PBMC.

  5. Protective effect of intranasal immunization with Neospora caninum membrane antigens against murine neosporosis established through the gastrointestinal tract

    PubMed Central

    Ferreirinha, Pedro; Dias, Joana; Correia, Alexandra; Pérez-Cabezas, Begoña; Santos, Carlos; Teixeira, Luzia; Ribeiro, Adília; Rocha, António; Vilanova, Manuel

    2014-01-01

    Neospora caninum is an Apicomplexa parasite that in the last two decades was acknowledged as the main pathogenic agent responsible for economic losses in the cattle industry. In the present study, the effectiveness of intranasal immunization with N. caninum membrane antigens plus CpG adjuvant was assessed in a murine model of intragastrically established neosporosis. Immunized mice presented a lower parasitic burden in the brain on infection with 5 × 107 tachyzoites, showing that significant protection was achieved by this immunization strategy. Intestinal IgA antibodies raised by immunization markedly agglutinated live N. caninum tachyzoites whereas previous opsonization with IgG antibodies purified from immunized mice sera reduced parasite survival within macrophage cells. Although an IgG1 : IgG2a ratio < 1 was detected in the immunized mice before and after infection, indicative of a predominant T helper type 1 immune response, no increased production of interferon-γ was detected in the spleen or mesenteric lymph nodes of the immunized mice. Altogether, these results show that mucosal immunization with N. caninum membrane proteins plus CpG adjuvant protect against intragastrically established neosporosis and indicate that parasite-specific mucosal and circulating antibodies have a protective role against this parasitic infection. PMID:24128071

  6. Crosstalk between platelets and the complement system in immune protection and disease.

    PubMed

    Verschoor, A; Langer, H F

    2013-11-01

    Platelets have a central function in repairing vascular damage and stopping acute blood loss. They are equally central to thrombus formation in cardiovascular diseases such as myocardial infarction and ischaemic stroke. Beyond these classical prothrombotic diseases, immune mediated pathologies such as haemolytic uraemic syndrome (HUS) or paroxysmal nocturnal haemoglobinuria (PNH) also feature an increased tendency to form thrombi in various tissues. It has become increasingly clear that the complement system, part of the innate immune system, has an important role in the pathophysiology of these diseases. Not only does complement influence prothrombotic disease, it is equally involved in idiopathic thrombocytopenic purpura (ITP), an autoimmune disease characterised by thrombocytopenia. Thus, there are complex interrelationships between the haemostatic and immune systems, and platelets and complement in particular. Not only does complement influence platelet diseases such as ITP, HUS and PNH, it also mediates interaction between microbes and platelets during systemic infection, influencing the course of infection and development of protective immunity. This review aims to provide an integrative overview of the mechanisms underlying the interactions between complement and platelets in health and disease.

  7. Protective Immunity and Reduced Renal Colonization Induced by Vaccines Containing Recombinant Leptospira interrogans Outer Membrane Proteins and Flagellin Adjuvant.

    PubMed

    Monaris, D; Sbrogio-Almeida, M E; Dib, C C; Canhamero, T A; Souza, G O; Vasconcellos, S A; Ferreira, L C S; Abreu, P A E

    2015-08-01

    Leptospirosis is a global zoonotic disease caused by different Leptospira species, such as Leptospira interrogans, that colonize the renal tubules of wild and domestic animals. Thus far, attempts to develop effective leptospirosis vaccines, both for humans and animals, have failed to induce immune responses capable of conferring protection and simultaneously preventing renal colonization. In this study, we evaluated the protective immunity induced by subunit vaccines containing seven different recombinant Leptospira interrogans outer membrane proteins, including the carboxy-terminal portion of the immunoglobulinlike protein A (LigA(C)) and six novel antigens, combined with aluminum hydroxide (alum) or Salmonella flagellin (FliC) as adjuvants. Hamsters vaccinated with the different formulations elicited high antigen-specific antibody titers. Immunization with LigA(C), either with alum or flagellin, conferred protective immunity but did not prevent renal colonization. Similarly, animals immunized with LigA(C) or LigA(C) coadministered with six leptospiral proteins with alum adjuvant conferred protection but did not reduce renal colonization. In contrast, immunizing animals with the pool of seven antigens in combination with flagellin conferred protection and significantly reduced renal colonization by the pathogen. The present study emphasizes the relevance of antigen composition and added adjuvant in the efficacy of antileptospirosis subunit vaccines and shows the complex relationship between immune responses and renal colonization by the pathogen. PMID:26108285

  8. Protective Immunity and Reduced Renal Colonization Induced by Vaccines Containing Recombinant Leptospira interrogans Outer Membrane Proteins and Flagellin Adjuvant

    PubMed Central

    Monaris, D.; Sbrogio-Almeida, M. E.; Dib, C. C.; Canhamero, T. A.; Souza, G. O.; Vasconcellos, S. A.; Ferreira, L. C. S.

    2015-01-01

    Leptospirosis is a global zoonotic disease caused by different Leptospira species, such as Leptospira interrogans, that colonize the renal tubules of wild and domestic animals. Thus far, attempts to develop effective leptospirosis vaccines, both for humans and animals, have failed to induce immune responses capable of conferring protection and simultaneously preventing renal colonization. In this study, we evaluated the protective immunity induced by subunit vaccines containing seven different recombinant Leptospira interrogans outer membrane proteins, including the carboxy-terminal portion of the immunoglobulinlike protein A (LigAC) and six novel antigens, combined with aluminum hydroxide (alum) or Salmonella flagellin (FliC) as adjuvants. Hamsters vaccinated with the different formulations elicited high antigen-specific antibody titers. Immunization with LigAC, either with alum or flagellin, conferred protective immunity but did not prevent renal colonization. Similarly, animals immunized with LigAC or LigAC coadministered with six leptospiral proteins with alum adjuvant conferred protection but did not reduce renal colonization. In contrast, immunizing animals with the pool of seven antigens in combination with flagellin conferred protection and significantly reduced renal colonization by the pathogen. The present study emphasizes the relevance of antigen composition and added adjuvant in the efficacy of antileptospirosis subunit vaccines and shows the complex relationship between immune responses and renal colonization by the pathogen. PMID:26108285

  9. Transcutaneous immunization with toxin-coregulated pilin A induces protective immunity against Vibrio cholerae O1 El Tor challenge in mice.

    PubMed

    Rollenhagen, Julianne E; Kalsy, Anuj; Cerda, Francisca; John, Manohar; Harris, Jason B; Larocque, Regina C; Qadri, Firdausi; Calderwood, Stephen B; Taylor, Ronald K; Ryan, Edward T

    2006-10-01

    Toxin-coregulated pilin A (TcpA) is the main structural subunit of a type IV bundle-forming pilus of Vibrio cholerae, the cause of cholera. Toxin-coregulated pilus is involved in formation of microcolonies of V. cholerae at the intestinal surface, and strains of V. cholerae deficient in TcpA are attenuated and unable to colonize intestinal surfaces. Anti-TcpA immunity is common in humans recovering from cholera in Bangladesh, and immunization against TcpA is protective in murine V. cholerae models. To evaluate whether transcutaneously applied TcpA is immunogenic, we transcutaneously immunized mice with 100 mug of TcpA or TcpA with an immunoadjuvant (cholera toxin [CT], 50 mug) on days 0, 19, and 40. Mice immunized with TcpA alone did not develop anti-TcpA responses. Mice that received transcutaneously applied TcpA and CT developed prominent anti-TcpA immunoglobulin G (IgG) serum responses but minimal anti-TcpA IgA. Transcutaneous immunization with CT induced prominent IgG and IgA anti-CT serum responses. In an infant mouse model, offspring born to dams transcutaneously immunized either with TcpA and CT or with CT alone were challenged with 10(6) CFU (one 50% lethal dose) wild-type V. cholerae O1 El Tor strain N16961. At 48 h, mice born to females transcutaneously immunized with CT alone had 36% +/- 10% (mean +/- standard error of the mean) survival, while mice born to females transcutaneously immunized with TcpA and CT had 69% +/- 6% survival (P < 0.001). Our results suggest that transcutaneous immunization with TcpA and an immunoadjuvant induces protective anti-TcpA immune responses. Anti-TcpA responses may contribute to an optimal cholera vaccine.

  10. Early infections by myxoma virus of young rabbits (Oryctolagus cuniculus) protected by maternal antibodies activate their immune system and enhance herd immunity in wild populations

    PubMed Central

    2014-01-01

    The role of maternal antibodies is to protect newborns against acute early infection by pathogens. This can be achieved either by preventing any infection or by allowing attenuated infections associated with activation of the immune system, the two strategies being based on different cost/benefit ratios. We carried out an epidemiological survey of myxomatosis, which is a highly lethal infectious disease, in two distant wild populations of rabbits to describe the epidemiological pattern of the disease. Detection of specific IgM and IgG enabled us to describe the pattern of immunity. We show that maternal immunity attenuates early infection of juveniles and enables activation of their immune system. This mechanism associated with steady circulation of the myxoma virus in both populations, which induces frequent reinfections of immune rabbits, leads to the maintenance of high immunity levels within populations. Thus, myxomatosis has a low impact, with most infections being asymptomatic. This work shows that infection of young rabbits protected by maternal antibodies induces attenuated disease and activates their immune system. This may play a major role in reducing the impact of a highly lethal disease when ecological conditions enable permanent circulation of the pathogen. PMID:24589193

  11. Early infections by myxoma virus of young rabbits (Oryctolagus cuniculus) protected by maternal antibodies activate their immune system and enhance herd immunity in wild populations.

    PubMed

    Marchandeau, Stéphane; Pontier, Dominique; Guitton, Jean-Sébastien; Letty, Jérôme; Fouchet, David; Aubineau, Jacky; Berger, Francis; Léonard, Yves; Roobrouck, Alain; Gelfi, Jacqueline; Peralta, Brigitte; Bertagnoli, Stéphane

    2014-03-04

    The role of maternal antibodies is to protect newborns against acute early infection by pathogens. This can be achieved either by preventing any infection or by allowing attenuated infections associated with activation of the immune system, the two strategies being based on different cost/benefit ratios. We carried out an epidemiological survey of myxomatosis, which is a highly lethal infectious disease, in two distant wild populations of rabbits to describe the epidemiological pattern of the disease. Detection of specific IgM and IgG enabled us to describe the pattern of immunity. We show that maternal immunity attenuates early infection of juveniles and enables activation of their immune system. This mechanism associated with steady circulation of the myxoma virus in both populations, which induces frequent reinfections of immune rabbits, leads to the maintenance of high immunity levels within populations. Thus, myxomatosis has a low impact, with most infections being asymptomatic. This work shows that infection of young rabbits protected by maternal antibodies induces attenuated disease and activates their immune system. This may play a major role in reducing the impact of a highly lethal disease when ecological conditions enable permanent circulation of the pathogen.

  12. Co-expression of Interleukin-15 Enhances the Protective Immune Responses Induced by Immunization with a Murine Malaria MVA-Based Vaccine Encoding the Circumsporozoite Protein.

    PubMed

    Parra, Marcela; Liu, Xia; Derrick, Steven C; Yang, Amy; Molina-Cruz, Alvaro; Barillas-Mury, Carolina; Zheng, Hong; Thao Pham, Phuong; Sedegah, Martha; Belmonte, Arnel; Litilit, Dianne D; Waldmann, Thomas A; Kumar, Sanjai; Morris, Sheldon L; Perera, Liyanage P

    2015-01-01

    Malaria remains a major global public health problem with an estimated 200 million cases detected in 2012. Although the most advanced candidate malaria vaccine (RTS,S) has shown promise in clinical trials, its modest efficacy and durability have created uncertainty about the impact of RTS,S immunization (when used alone) on global malaria transmission. Here we describe the development and characterization of a novel modified vaccinia virus Ankara (MVA)-based malaria vaccine which co-expresses the Plasmodium yoelii circumsporozoite protein (CSP) and IL-15. Vaccination/challenge studies showed that C57BL/6 mice immunized with the MVA-CSP/IL15 vaccine were protected significantly better against a P. yoelii 17XNL sporozoite challenge than either mice immunized with an MVA vaccine expressing only CSP or naïve controls. Importantly, the levels of total anti-CSP IgG were elevated about 100-fold for the MVA-CSP/IL15 immunized group compared to mice immunized with the MVA-CSP construct that does not express IL-15. Among the IgG subtypes, the IL-15 expressing MVA-CSP vaccine induced levels of IgG1 (8 fold) and IgG2b (80 fold) higher than the MVA-CSP construct. The significantly enhanced humoral responses and protection detected after immunization with the MVA-CSP/IL15 vaccine suggest that this IL-15 expressing MVA construct could be considered in the development of future malaria immunization strategies.

  13. Active Immunization with Extracellular Vesicles Derived from Staphylococcus aureus Effectively Protects against Staphylococcal Lung Infections, Mainly via Th1 Cell-Mediated Immunity.

    PubMed

    Choi, Seng Jin; Kim, Min-Hye; Jeon, Jinseong; Kim, Oh Youn; Choi, Youngwoo; Seo, Jihye; Hong, Sung-Wook; Lee, Won-Hee; Jeon, Seong Gyu; Gho, Yong Song; Jee, Young-Koo; Kim, Yoon-Keun

    2015-01-01

    Staphylococcus aureus is an important pathogenic bacterium that causes various infectious diseases. Extracellular vesicles (EVs) released from S. aureus contain bacterial proteins, nucleic acids, and lipids. These EVs can induce immune responses leading to similar symptoms as during staphylococcal infection condition and have the potential as vaccination agent. Here, we show that active immunization (vaccination) with S. aureus-derived EVs induce adaptive immunity of antibody and T cell responses. In addition, these EVs have the vaccine adjuvant ability to induce protective immunity such as the up-regulation of co-stimulatory molecules and the expression of T cell polarizing cytokines in antigen-presenting cells. Moreover, vaccination with S. aureus EVs conferred protection against lethality induced by airway challenge with lethal dose of S. aureus and also pneumonia induced by the administration of sub-lethal dose of S. aureus. These protective effects were also found in mice that were adoptively transferred with splenic T cells isolated from S. aureus EV-immunized mice, but not in serum transferred mice. Furthermore, this protective effect of S. aureus EVs was significantly reduced by the absence of interferon-gamma, but not by the absence of interleukin-17. Together, the study herein suggests that S. aureus EVs are a novel vaccine candidate against S. aureus infections, mainly via Th1 cellular response.

  14. Limited Protection from a Pathogenic Chimeric Simian-Human Immunodeficiency Virus Challenge following Immunization with Attenuated Simian Immunodeficiency Virus

    PubMed Central

    Lewis, Mark G.; Yalley-Ogunro, Jake; Greenhouse, Jack J.; Brennan, Terry P.; Jiang, Jennifer Bo; VanCott, Thomas C.; Lu, Yichen; Eddy, Gerald A.; Birx, Deborah L.

    1999-01-01

    Two live attenuated single-deletion mutant simian immunodeficiency virus (SIV) constructs, SIV239Δnef and SIVPBj6.6Δnef, were tested for their abilities to stimulate protective immunity in macaques. During the immunization period the animals were examined for specific immune responses and virus growth. Each construct generated high levels of specific immunity in all of the immunized animals. The SIV239Δnef construct was found to grow to high levels in all immunized animals, with some animals remaining positive for virus isolation and plasma RNA throughout the immunization period. The SIVPBj6.6Δnef was effectively controlled by all of the immunized animals, with virus mostly isolated only during the first few months following immunization and plasma RNA never detected. Following an extended period of immunization of over 80 weeks, the animals were challenged with a pathogenic simian-human immunodeficiency virus (SHIV) isolate, SIV89.6PD, by intravenous injection. All of the SIV239Δnef-immunized animals became infected with the SHIV isolate; two of five animals eventually controlled the challenge and three of five animals, which failed to check the immunizing virus, progressed to disease state before the unvaccinated controls. One of five animals immunized with SIVPBj6.6Δnef totally resisted infection by the challenge virus, while three others limited its growth and the remaining animal became persistently infected and eventually died of a pulmonary thrombus. These data indicate that vaccination with attenuated SIV can protect macaques from disease and in some cases from infection by a divergent SHIV. However, if animals are unable to control the immunizing virus, potential damage that can accelerate the disease course of a pathogenic challenge virus may occur. PMID:9882330

  15. Of Mice and Men: Protective and Pathogenic Immune Responses to West Nile virus Infection

    PubMed Central

    Trobaugh, Derek

    2015-01-01

    West Nile virus, a mosquito-borne flavivirus, first emerged in the Western Hemisphere in 1999. Although the majority of infections are asymptomatic, WNV causes significant morbidity and mortality in a minority of individuals who develop neuroinvasive disease, in particular the elderly and immunocompromised. Research in animal models has demonstrated interactions between WNV and the innate and adaptive immune system, some of which protect the host and others which are deleterious. Studies of disease pathogenesis in humans are less numerous, largely due to the complexities of WNV epidemiology. Human studies that have been done support the notion that innate and adaptive immune responses are delicately balanced and may help or harm the host. Further human investigations are needed to characterize beneficial responses to WNV with the goal of such research leading to therapeutics and effective vaccines in order to control this emerging viral disease. PMID:26120511

  16. Induction of protective immunity to anthrax lethal toxin with a nonhuman primate adenovirus-based vaccine in the presence of preexisting anti-human adenovirus immunity.

    PubMed

    Hashimoto, Masahiko; Boyer, Julie L; Hackett, Neil R; Wilson, James M; Crystal, Ronald G

    2005-10-01

    Prevention or therapy for bioterrorism-associated anthrax infections requires rapidly acting effective vaccines. We recently demonstrated (Y. Tan, N. R. Hackett, J. L. Boyer, and R. G. Crystal, Hum. Gene Ther. 14:1673-1682, 2003) that a single administration of a recombinant serotype 5 adenovirus (Ad) vector expressing anthrax protective antigen (PA) provides rapid protection against anthrax lethal toxin challenge. However, approximately 35 to 50% of humans have preexisting neutralizing antibodies against Ad5. This study assesses the hypothesis that a recombinant adenovirus vaccine based on the nonhuman primate-derived serotype AdC7, against which humans do not have immunity, expressing PA (AdC7PA) will protect against anthrax lethal toxin even in the presence of preexisting anti-Ad5 immunity. Naive and Ad5-immunized BALB/c mice received (intramuscularly) 10(8) to 10(11) particle units (PU) of AdC7PA, Ad5PA (a human serotype Ad5-based vector expressing a secreted form of PA), or AdNull (an Ad5 vector with no transgene). Robust anti-PA immunoglobulin G and neutralizing antibodies were detected by 2 to 4 weeks following administration of AdC7PA to naive or Ad5 preimmunized mice, whereas low anti-PA titers were detected in Ad5-preimmunized mice following administration of Ad5PA. To assess protection in vivo, naive or mice previously immunized against Ad5 were immunized with AdC7PA or Ad5PA and then challenged with a lethal intravenous dose of Bacillus anthracis lethal toxin. Whereas Ad5PA protected naive mice against challenge with B. anthracis lethal toxin, Ad5PA was ineffective in mice that were previously immunized against Ad5. In contrast, AdC7PA functioned effectively not only to protect naive mice but also to protect Ad5-preimmunized mice, with 100% survival after lethal toxin challenge. These data suggest the nonhuman-based vector AdC7PA is an effective vaccine for the development of protective immunity against B. anthracis and importantly functions as a "sero

  17. PD-1 suppresses protective immunity to Streptococcus pneumoniae through a B cell-intrinsic mechanism

    PubMed Central

    McKay, Jerome T.; Egan, Ryan P.; Yammani, Rama D.; Chen, Lieping; Shin, Tahiro; Yagita, Hideo; Haas, Karen M.

    2015-01-01

    Despite the emergence of the PD-1:PD-1 ligand (PD-L) regulatory axis as a promising target for treating multiple human diseases, remarkably little is known about how this pathway regulates responses to extracellular bacterial infections. We found that PD-1−/− mice, as well as wild type mice treated with a PD-1 blocking antibody, exhibited significantly increased survival against lethal Streptococcus pneumoniae infection following either priming with low-dose pneumococcal respiratory infection or S. pneumoniae-capsular polysaccharide immunization. Enhanced survival in mice with disrupted PD-1:PD-L interactions was explained by significantly increased proliferation, isotype switching, and IgG production by pneumococcal capsule-specific B cells. Both PD-1 ligands, B7-H1 and B7-DC, contributed to PD-1-mediated suppression of protective capsule-specific IgG. Importantly, PD-1 was induced on capsule-specific B cells and suppressed IgG production and protection against pneumococcal infection in a B cell-intrinsic manner. These results provide the first demonstration of a physiologic role for B cell-intrinsic PD-1 expression in vivo. In summary, our study reveals that B cell-expressed PD-1 plays a central role in regulating protection against S. pneumoniae, and thereby represents a promising target for bolstering immunity to encapsulated bacteria. PMID:25624454

  18. Virtual memory T cells develop and mediate bystander protective immunity in an IL-15-dependent manner

    PubMed Central

    White, Jason T.; Cross, Eric W.; Burchill, Matthew A.; Danhorn, Thomas; McCarter, Martin D.; Rosen, Hugo R.; O'Connor, Brian; Kedl, Ross M.

    2016-01-01

    Virtual memory cells (VM) are an antigen-specific, memory phenotype CD8 T-cell subset found in lymphoreplete, unchallenged mice. Previous studies indicated that VM cells were the result of homeostatic proliferation (HP) resembling the proliferation observed in a lymphopenic environment. Here we demonstrate that HP is ongoing in lymphoreplete mice, the degree of which is dictated by the number of naive CD8 T cells with a sufficiently high affinity for self-antigen interacting with peripheral IL-15. VM cell transcriptional profiles suggest a capacity to mediate protective immunity via antigen non-specific bystander killing, a function we show is dependent on IL-15. Finally, we show a VM-like population of human cells that accumulate with age and traffic to the liver, displaying phenotypic and functional attributes consistent with the bystander protective functions of VM cells identified in the mouse. These data identify developmental and functional attributes of VM cells, including their likely role in protective immunity. PMID:27097762

  19. Virtual memory T cells develop and mediate bystander protective immunity in an IL-15-dependent manner.

    PubMed

    White, Jason T; Cross, Eric W; Burchill, Matthew A; Danhorn, Thomas; McCarter, Martin D; Rosen, Hugo R; O'Connor, Brian; Kedl, Ross M

    2016-01-01

    Virtual memory cells (VM) are an antigen-specific, memory phenotype CD8 T-cell subset found in lymphoreplete, unchallenged mice. Previous studies indicated that VM cells were the result of homeostatic proliferation (HP) resembling the proliferation observed in a lymphopenic environment. Here we demonstrate that HP is ongoing in lymphoreplete mice, the degree of which is dictated by the number of naive CD8 T cells with a sufficiently high affinity for self-antigen interacting with peripheral IL-15. VM cell transcriptional profiles suggest a capacity to mediate protective immunity via antigen non-specific bystander killing, a function we show is dependent on IL-15. Finally, we show a VM-like population of human cells that accumulate with age and traffic to the liver, displaying phenotypic and functional attributes consistent with the bystander protective functions of VM cells identified in the mouse. These data identify developmental and functional attributes of VM cells, including their likely role in protective immunity. PMID:27097762

  20. Novel 6xHis tagged foot-and-mouth disease virus vaccine bound to nanolipoprotein adjuvant via metal ions provides antigenic distinction and effective protective immunity.

    PubMed

    Rai, Devendra K; Segundo, Fayna Diaz-San; Schafer, Elizabeth; Burrage, Thomas G; Rodriguez, Luis L; de Los Santos, Teresa; Hoeprich, Paul D; Rieder, Elizabeth

    2016-08-01

    Here, we engineered two FMD viruses with histidine residues inserted into or fused to the FMDV capsid. Both 6xHis viruses exhibited growth kinetics, plaque morphologies and antigenic characteristics similar to wild-type virus. The 6xHis tag allowed one-step purification of the mutant virions by Co(2+) affinity columns. Electron microscopy and biochemical assays showed that the 6xHis FMDVs readily assembled into antigen: adjuvant complexes in solution, by conjugating with Ni(2+)-chelated nanolipoprotein and monophosphoryl lipid A adjuvant (MPLA:NiNLP). Animals Immunized with the inactivated 6xHis-FMDV:MPLA:NiNLP vaccine acquired enhanced protective immunity against FMDV challenge compared to virions alone. Induction of anti-6xHis and anti-FMDV neutralizing antibodies in the immunized animals could be exploited in the differentiation of vaccinated from infected animals needed for the improvement of FMD control measures. The novel marker vaccine/nanolipid technology described here has broad applications for the development of distinctive and effective immune responses to other pathogens of importance. PMID:27209448

  1. Protective Immunity Against Homologous and Heterologous Influenza Virus Lethal Challenge by Immunization with New Recombinant Chimeric HA2-M2e Fusion Protein in BALB/C Mice.

    PubMed

    Ameghi, Ali; Pilehvar-Soltanahmadi, Yones; Baradaran, Behzad; Barzegar, Abolfazl; Taghizadeh, Morteza; Zarghami, Nosratollah; Aghaiypour, Khosrow

    2016-05-01

    Influenza is an acute and highly contagious respiratory disease. The error prone RNA polymerase and segmented nature of the influenza A virus genome allow antigenic drift and shift, respectively. Therefore, most influenza vaccines are inefficient along time and against different viral subtypes. In this study, for the first time, protection properties of a new recombinant fusion of HA2 and M2e peptides originated from influenza virus A/Brisbane/59/2007-like (H1N1) in BALB/c mice model were investigated. After immunization of the BALB/c mice, the protection property of fusion peptide was determined by a neutralizing assay test. For further study, mice were lethal challenged by the (mouse adapted, A/PR8/34 [H1N1]) and heterologous (mouse adapted, A/Brisbane/10/2007 [H3N2]) influenza virus subtypes. Then, the lung viral titers, body weight, and survival rate of the immunized mice were monitored. The results showed that immunization by the M2e-HA2 recombinant fusion peptide provides strong protection against homologous challenge and an infirm protection against heterologous. These protections against homologous and heterologous influenza A virus challenges meant the universal nature of these recombinant peptides in an immunity manner against influenza A virus. However, more studies are needed to optimize this recombinant construction, and this experiment recommends HA2-M2e fusion peptide as a universal influenza A vaccine candidate. PMID:27058011

  2. Protective effects of Zhuyeqing liquor on the immune function of normal and immunosuppressed mice in vivo

    PubMed Central

    2013-01-01

    Background Zhuyeqing Liquor (ZYQL), a well-known Chinese traditional health liquor, has various biological properties, including anti-oxidant, anti-inflammatory, immunoenhancement and cardiovascular protective effects. Methods The protective effects of Zhuyeqing Liquor (ZYQL) on the immune function was investigated in vivo in normal healthy mice and immunosuppressed mice treated with Cyclophosphamide (Cy, 100 mg/kg) by intraperitoneal injection on days 4, 8 and 12. ZYQL (100, 200 and 400 mg/kg) was administered via gavage daily for 14 days. The phagocytotic function of mononuclear phagocytic system was detected with carbon clearance methods, the levels of interleukin-6 (IL-6) and interferon-gamma (IFN-γ) in serum were detected with Enzyme linked immunosorbent assay (ELISA). Immune organs were weighed and organ indexes (organ weight/body weight) of thymus and spleen were calculated. Meanwhile, the activity of lysozyme (LSZ) in serum and the activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT) in spleen tissue were measured. Results ZYQL significantly upgrades the K value for clearance of carbon particles in normal mice treated with ZYQL (400 mg/kg) and immunosuppressed mice treated with ZYQL (100, 200 and 400 mg/kg) together with Cy (100 mg/kg) in vivo. The treatment of ZYQL (100, 200 and 400 mg/kg) effectively increased the activity of serum lysozyme as well as promoted the serum levels of IL-6 and IFN-γ in normal mice and immunosuppressed mice. Furthermore, ZYQL (100, 200 and 400 mg/kg) had an antioxidant effects in immune system by enhancing the antioxidant enzyme activity of SOD, CAT and GSH-Px in vivo. In addition, ZYQL (100, 200 and 400 mg/kg) effectively elevated the Cy-induced decreased organ index (thymus and spleen). Conclusions The present work shows that the dose-dependent administration of ZYQL is capable of influencing immune responses, which implying that its valuable functional health may be attributed

  3. Intradermal vaccination with un-adjuvanted sub-unit vaccines triggers skin innate immunity and confers protective respiratory immunity in domestic swine.

    PubMed

    Le Luduec, Jean-Benoît; Debeer, Sabine; Piras, Fabienne; Andréoni, Christine; Boudet, Florence; Laurent, Philippe; Kaiserlian, Dominique; Dubois, Bertrand

    2016-02-10

    Intradermal (ID) vaccination constitutes a promising approach to induce anti-infectious immunity. This route of immunization has mostly been studied with influenza split-virion vaccines. However, the efficacy of ID vaccination for sub-unit vaccines in relation to underlying skin innate immunity remains to be explored for wider application in humans. Relevant animal models that more closely mimic human skin immunity than the widely used mouse models are therefore necessary. Here, we show in domestic swine, which shares striking anatomic and functional properties with human skin, that a single ID delivery of pseudorabies virus (PRV) glycoproteins without added adjuvant is sufficient to trigger adaptive cellular and humoral immune responses, and to confer protection from a lethal respiratory infection with PRV. Analysis of early events at the skin injection site revealed up-regulation of pro-inflammatory cytokine and chemokine genes, recruitment of neutrophils and monocytes and accumulation of inflammatory DC. We further show that the sustained induction of pro-inflammatory cytokine genes results from the combined effects of skin puncture, liquid injection in the dermis and viral antigens. These data highlight that immune protection against respiratory infection can be induced by ID vaccination with a subunit vaccine and reveal that adjuvant requirements are circumvented by the mechanical and antigenic stress caused by ID injection, which triggers innate immunity and mobilization of inflammatory DC at the immunization site. ID vaccination with sub-unit vaccines may thus represent a safe and efficient solution for protection against respiratory infections in swine and possibly also in humans, given the similarity of skin structure and function in both species.

  4. Sublingual Immunization of Trivalent Human Papillomavirus DNA Vaccine in Baculovirus Nanovector for Protection against Vaginal Challenge

    PubMed Central

    Lee, Hee-Jung; Cho, Hansam; Kim, Mi-Gyeong; Heo, Yoon-Ki; Cho, Yeondong; Gwon, Yong-Dae; Park, Ki Hoon; Jin, Hyerim; Kim, Jinyoung; Oh, Yu-Kyoung; Kim, Young Bong

    2015-01-01

    Here, we report the immunogenicity of a sublingually delivered, trivalent human papillomavirus (HPV) DNA vaccine encapsidated in a human endogenous retrovirus (HERV) envelope-coated, nonreplicable, baculovirus nanovector. The HERV envelope-coated, nonreplicable, baculovirus-based DNA vaccine, encoding HPV16L1, -18L1 and -58L1 (AcHERV-triHPV), was constructed and sublingually administered to mice without adjuvant. Following sublingual (SL) administration, AcHERV-triHPV was absorbed and distributed throughout the body. At 15 minutes and 1 day post-dose, the distribution of AcHERV-triHPV to the lung was higher than that to other tissues. At 30 days post-dose, the levels of AcHERV-triHPV had diminished throughout the body. Six weeks after the first of three doses, 1×108 copies of SL AcHERV-triHPV induced HPV type-specific serum IgG and neutralizing antibodies to a degree comparable to that of IM immunization with 1×109 copies. AcHERV-triHPV induced HPV type-specific vaginal IgA titers in a dose-dependent manner. SL immunization with 1×1010 copies of AcHERV-triHPV induced Th1 and Th2 cellular responses comparable to IM immunization with 1×109 copies. Molecular imaging revealed that SL AcHERV-triHPV in mice provided complete protection against vaginal challenge with HPV16, HPV18, and HPV58 pseudoviruses. These results support the potential of SL immunization using multivalent DNA vaccine in baculovirus nanovector for induction of mucosal, systemic, and cellular immune responses. PMID:25789464

  5. Identifying the Role of E2 Domains on Alphavirus Neutralization and Protective Immune Responses

    PubMed Central

    Weger-Lucarelli, James; Aliota, Matthew T.; Kamlangdee, Attapon; Osorio, Jorge E.

    2015-01-01

    Background Chikungunya virus (CHIKV) and other alphaviruses are the etiologic agents of numerous diseases in both humans and animals. Despite this, the viral mediators of protective immunity against alphaviruses are poorly understood, highlighted by the lack of a licensed human vaccine for any member of this virus genus. The alphavirus E2, the receptor-binding envelope protein, is considered to be the predominant target of the protective host immune response. Although envelope protein domains have been studied for vaccine and neutralization in flaviviruses, their role in alphaviruses is less characterized. Here, we describe the role of the alphavirus E2 domains in neutralization and protection through the use of chimeric viruses. Methodology/Principal Findings Four chimeric viruses were constructed in which individual E2 domains of CHIKV were replaced with the corresponding domain from Semliki Forest virus (SFV) (ΔDomA/ΔDomB/ΔDomC/ ΔDomA+B). Vaccination studies in mice (both live and inactivated virus) revealed that domain B was the primary determinant of neutralization. Neutralization studies with CHIKV immune serum from humans were consistent with mouse studies, as ΔDomB was poorly neutralized. Conclusions/Significance Using chimeric viruses, it was determined that the alphavirus E2 domain B was the critical target of neutralizing antibodies in both mice and humans. Therefore, chimeric viruses may have more relevance for vaccine discovery than peptide-based approaches, which only detect linear epitopes. This study provides new insight into the role of alphavirus E2 domains on neutralization determinants and may be useful for the design of novel therapeutic technologies. PMID:26473963

  6. Immune cell-mediated protection of the mammary gland and the infant during breastfeeding.

    PubMed

    Hassiotou, Foteini; Geddes, Donna T

    2015-05-01

    Breastfeeding has been regarded first and foremost as a means of nutrition for infants, providing essential components for their unique growth and developmental requirements. However, breast milk is also rich in immunologic factors, highlighting its importance as a mediator of protection. In accordance with its evolutionary origin, the mammary gland offers via the breastfeeding route continuation of the maternal to infant immunologic support established in utero. At birth, the infant's immune system is immature, and although it was exposed to the maternal microbial flora during pregnancy, it experiences an abrupt change in its microbial environment during and after birth, which is challenging and renders the infant highly susceptible to infection. Active and passive immunity protects the infant via breast milk, which is rich in immunoglobulins, lactoferrin, lysozyme, cytokines, and numerous other immunologic factors, including maternal leukocytes. Breast milk leukocytes provide active immunity and promote development of immunocompetence in the infant. Additionally, it has been speculated that they play a role in the protection of the mammary gland from infection. Leukocytes are thought to exert these functions via phagocytosis, secretion of antimicrobial factors and/or antigen presentation in both the mammary gland and the gastrointestinal tract of the infant, and also in other infant tissues, where they are transported via the systemic circulation. Recently, it has been demonstrated that breast milk leukocytes respond dynamically to maternal as well as infant infections, and are fewer in nonexclusively compared with exclusively breastfeeding dyads, further emphasizing their importance for both the mother and infant. This review summarizes the current knowledge of human milk leukocytes and factors influencing them, and presents recent novel findings supporting their potential as a diagnostic marker for infections of the lactating breast and of the breastfed infant.

  7. Immune Cell–Mediated Protection of the Mammary Gland and the Infant during Breastfeeding1234

    PubMed Central

    Hassiotou, Foteini; Geddes, Donna T

    2015-01-01

    Breastfeeding has been regarded first and foremost as a means of nutrition for infants, providing essential components for their unique growth and developmental requirements. However, breast milk is also rich in immunologic factors, highlighting its importance as a mediator of protection. In accordance with its evolutionary origin, the mammary gland offers via the breastfeeding route continuation of the maternal to infant immunologic support established in utero. At birth, the infant’s immune system is immature, and although it was exposed to the maternal microbial flora during pregnancy, it experiences an abrupt change in its microbial environment during and after birth, which is challenging and renders the infant highly susceptible to infection. Active and passive immunity protects the infant via breast milk, which is rich in immunoglobulins, lactoferrin, lysozyme, cytokines, and numerous other immunologic factors, including maternal leukocytes. Breast milk leukocytes provide active immunity and promote development of immunocompetence in the infant. Additionally, it has been speculated that they play a role in the protection of the mammary gland from infection. Leukocytes are thought to exert these functions via phagocytosis, secretion of antimicrobial factors and/or antigen presentation in both the mammary gland and the gastrointestinal tract of the infant, and also in other infant tissues, where they are transported via the systemic circulation. Recently, it has been demonstrated that breast milk leukocytes respond dynamically to maternal as well as infant infections, and are fewer in nonexclusively compared with exclusively breastfeeding dyads, further emphasizing their importance for both the mother and infant. This review summarizes the current knowledge of human milk leukocytes and factors influencing them, and presents recent novel findings supporting their potential as a diagnostic marker for infections of the lactating breast and of the breastfed

  8. Antigen export during liver infection of the malaria parasite augments protective immunity.

    PubMed

    Montagna, Georgina N; Beigier-Bompadre, Macarena; Becker, Martina; Kroczek, Richard A; Kaufmann, Stefan H E; Matuschewski, Kai

    2014-01-01

    Protective immunity against preerythrocytic malaria parasite infection is difficult to achieve. Intracellular Plasmodium parasites likely minimize antigen presentation by surface-expressed major histocompatibility complex class I (MHC-I) molecules on infected cells, yet they actively remodel their host cells by export of parasite factors. Whether exported liver-stage proteins constitute better candidates for MHC-I antigen presentation to CD8(+) T lymphocytes remains unknown. Here, we systematically characterized the contribution of protein export to the magnitude of antigen-specific T-cell responses against Plasmodium berghei liver-stage parasites in C57BL/6 mice. We generated transgenic sporozoites that secrete a truncated ovalbumin (OVA) surrogate antigen only in the presence of an amino-terminal protein export element. Immunization with live attenuated transgenic sporozoites revealed that antigen export was not critical for CD8(+) T-cell priming but enhanced CD8(+) T-cell proliferation in the liver. Upon transfer of antigen-specific CD8(+) T cells, liver-stage parasites secreting the target protein were eliminated more efficiently. We conclude that Plasmodium parasites strictly control protein export during liver infection to minimize immune recognition. Strategies that enhance the discharge of parasite proteins into infected hepatocytes could improve the efficacy of candidate preerythrocytic malaria vaccines. Importance: Vaccine development against Plasmodium parasites remains a priority in malaria research. The most advanced malaria subunit vaccine candidates contain Plasmodium surface proteins with important roles for parasite vital functions. A fundamental question is whether recognition by effector CD8(+) T cells is restricted to sporozoite surface antigens or extends to parasite proteins that are synthesized during the extensive parasite expansion phase in the liver. Using a surrogate model antigen, we found that a cytoplasmic antigen is able to induce

  9. Immunization with Potato Plants Expressing VP60 Protein Protects against Rabbit Hemorrhagic Disease Virus

    PubMed Central

    Castañón, S.; Marín, M. S.; Martín-Alonso, J. M.; Boga, J. A.; Casais, R.; Humara, J. M.; Ordás, R. J.; Parra, F.

    1999-01-01

    The major structural protein VP60 of rabbit hemorrhagic disease virus (RHDV) has been produced in transgenic potato plants under the control of a cauliflower mosaic virus 35S promoter or a modified 35S promoter that included two copies of a strong transcriptional enhancer. Both types of promoters allowed the production of specific mRNAs and detectable levels of recombinant VP60, which were higher for the constructs carrying the modified 35S promoter. Rabbits immunized with leaf extracts from plants carrying this modified 35S promoter showed high anti-VP60 antibody titers and were fully protected against the hemorrhagic disease. PMID:10196345

  10. Protective immunity in cattle vaccinated with a commercial scale, inactivated, bivalent vesicular stomatitis vaccine.

    PubMed

    House, James A; House, Carol; Dubourget, Philippe; Lombard, Michel

    2003-05-16

    A commercially prepared oil-adjuvanted, inactivated vaccine containing antigens of vesicular stomatitis virus (VSV) serotypes New Jersey (NJ) and Indiana 1 (IND1) was administered to calves to determine its ability to induce protective immunity. Weekly serological studies were conducted. The 12 calves in Group I were vaccinated once and challenge inoculated with VSV New Jersey 28 days later. Two calves were fully protected and two were partially protected. The five calves in Group II were vaccinated twice 40 days apart and challenge inoculated on 14 days post-second vaccination (dp2v) with VSV Indiana 1. All animals were fully protected. The 14 calves in Group III were vaccinated twice 91 days apart and challenge inoculated on 91 dp2v with VSV Indiana 1. All animals were fully protected. All control calves in each group became clinically ill. Two calves inoculated with VSV Indiana 1 challenge virus on day 0 and 11 weeks later showed clinical disease after each inoculation. No virus was isolated from the blood of four acutely ill calves 48 h after challenge inoculation. PMID:12706679

  11. aroA deleted Bordetella bronchiseptica inspiring robust mucosal immune response and provide full protection against intranasal challenge.

    PubMed

    Zhang, Qian; Hu, Ruiming; Hu, Junyong; He, Hua; Tang, Xibiao; Jin, Meilin; Chen, Huanchun; Wu, Bin

    2013-02-01

    Bordetella bronchiseptica is a Gram-negative respiratory pathogen responsible for atrophic rhinitis and bronchopneumonia in swine. Several vaccines aimed at preventing B. bronchiseptica have been used, but a safe and efficient live vaccine for use in piglets remains elusive. In this study, we constructed an aroA-deleted B. bronchiseptica strain (QH0814) and evaluated its safety and protective efficiency in piglets. Lung lesion scores in QH0814-immunized piglets post-challenge were significantly lower than those in piglets immunized with the parent strain (P<0.05). Immunization with QH0814 induced a vigorous immune response, especially at the mucosal surface of the respiratory tract. IgA titers in bronchoalveolar lavage fluid (BALF) and serum were significantly higher in the QH0814-immunized group compared to the inactivated-vaccine-immunized group. Piglets immunized with QH0814 were better protected than those in the inactivated-vaccine and negative control groups. The clinical symptoms, histopathological changes and immune responses elicited in the piglets were recorded. The results of this study suggest that QH0814 was able to confer complete protection against B. bronchiseptica infection and could thus be used as a candidate attenuated live vaccine against B. bronchiseptica in piglets.

  12. Heat killed multi-serotype Shigella immunogens induced humoral immunity and protection against heterologous challenge in rabbit model.

    PubMed

    Nag, Dhrubajyoti; Sinha, Ritam; Mitra, Soma; Barman, Soumik; Takeda, Yoshifumi; Shinoda, Sumio; Chakrabarti, M K; Koley, Hemanta

    2015-11-01

    Recently we have shown the homologous protective efficacy of heat killed multi-serotype Shigella (HKMS) immunogens in a guinea pig colitis model. In our present study, we have advanced our research by immunizing rabbits with a reduced number of oral doses and evaluating the host's adaptive immune responses. The duration of immunogenicity and subsequently protective efficacy was determined against wild type heterologous Shigella strains in a rabbit luminal model. After three successive oral immunizations with HKMS immunogens, serum and lymphocyte supernatant antibody titer against the heterologous shigellae were reciprocally increased and remained at an elevated level up to 180 days. Serogroup and serotype specific O-antigen of lipopolysaccharide and immunogenic proteins of heterologous challenge strains were detected by immunoblot assay. Up-regulation of IL-12p35, IFN-γ and IL-10 mRNA expression was detected in immunized rabbit peripheral blood mononuclear cells (PBMC) after stimulation with HKMS in vitro. HKMS-specific plasma cell response was confirmed by production of a relatively higher level of HKMS-specific IgG in immunized PBMC supernatant compared to control group. Furthermore, the immunized groups of rabbits exhibited complete protection against wild type heterologous shigellae challenge. Thus HKMS immunogens induced humoral and Th1-mediated adaptive immunity and provided complete protection in a rabbit model. These immunogens could be a broad spectrum non-living vaccine candidate for human use in the near future.

  13. Immune Protection of Retroviral Vectors Upon Molecular Painting with the Complement Regulatory Protein CD59.

    PubMed

    Heider, Susanne; Kleinberger, Sandra; Kochan, Feliks; Dangerfield, John A; Metzner, Christoph

    2016-07-01

    Glycosylphosphatidylinositol anchoring is a type of post-translational modification that allows proteins to be presented on the exterior side of the cell membrane. Purified glycosylphosphatidylinositol-anchored protein can spontaneously re-insert into lipid bilayer membranes in a process termed Molecular Painting. Here, we demonstrate the possibility of inserting purified, recombinant CD59 into virus particles produced from a murine retroviral producer cell line. CD59 is a regulator of the complement system that helps protect healthy cells from the lytic activity of the complement cascade. In this study, we could show that Molecular Painting confers protection from complement activity upon murine retroviral vector particles. Indeed, increased infectivity of CD59-modified virus particles was observed upon challenge with human serum, indicating that Molecular Painting is suitable for modulating the immune system in gene therapy or vaccination applications. PMID:27170144

  14. Active immunization with recombinant V antigen from Yersinia pestis protects mice against plague.

    PubMed Central

    Leary, S E; Williamson, E D; Griffin, K F; Russell, P; Eley, S M; Titball, R W

    1995-01-01

    The gene encoding V antigen from Yersinia pestis was cloned into the plasmid expression vector pGEX-5X-2. When electroporated into Escherichia coli JM109, the recombinant expressed V antigen as a stable fusion protein with glutathione S-transferase. The glutathione S-transferase-V fusion protein was isolated from recombinant E. coli and cleaved with factor Xa to yield purified V antigen as a stable product. Recombinant V antigen was inoculated intraperitoneally into mice and shown to induce a protective immune response against a subcutaneous challenge with 3.74 x 10(6) CFU of virulent Y. pestis. Protection correlated with the induction of a high titer of serum antibodies and a T-cell response specific for recombinant V antigen. These results indicate that V antigen should be a major component of an improved vaccine for plague. PMID:7622205

  15. Protective Immunity to H7N9 Influenza viruses elicited by synthetic DNA Vaccine

    PubMed Central

    Yan, Jian; Villarreal, Daniel O.; Racine, Trina; Chu, Jaemi S.; Walters, Jewell N.; Morrow, Matthew P.; Khan, Amir S.; Sardesai, Niranjan Y.; Kim, J. Joseph; Kobinger, Gary P.; Weiner, David B.

    2014-01-01

    Despite an intensive vaccine program influenza infections remain a major health problem, due to the viruses’ ability to change its envelope glycoprotein hemagglutinin (HA), through shift and drift, permitting influenza to escape protection induced by current vaccines or natural immunity. Recently a new variant, H7N9, has emerged in China causing global concern. First, there have been more than 130 laboratory-confirmed human infections resulting in an alarmingly high death rate (32.3%). Second, genetic changes found in H7N9 appear to be associated with enabling avian influenza viruses to spread more effectively in mammals, thus transmitting infections on a larger scale. Currently, no vaccines or drugs are effectively able to target H7N9. Here, we report the rapid development of a synthetic consensus DNA vaccine (pH7HA) to elicit potent protective immunity against the H7N9 viruses. We show that pH7HA induces broad antibody responses that bind to divergent HAs from multiple new members of the H7N9 family. These antibody responses result in high-titer HAI against H7N9. Simultaneously, this vaccine induces potent polyfunctional effector CD4 and CD8 T cell memory responses. Animals vaccinated with pH7HA are completely protected from H7N9 virus infection and any morbidity associated with lethal challenge. This study establishes that this synthetic consensus DNA vaccine represents a new tool for targeting emerging infection, and more importantly, its design, testing and development into seed stock for vaccine production in a few days in the pandemic setting has significant implications for the rapid deployment of vaccines protecting against emerging infectious diseases. PMID:24631084

  16. Protective immunity to H7N9 influenza viruses elicited by synthetic DNA vaccine.

    PubMed

    Yan, Jian; Villarreal, Daniel O; Racine, Trina; Chu, Jaemi S; Walters, Jewell N; Morrow, Matthew P; Khan, Amir S; Sardesai, Niranjan Y; Kim, J Joseph; Kobinger, Gary P; Weiner, David B

    2014-05-19

    Despite an intensive vaccine program influenza infections remain a major health problem, due to the viruses' ability to change its envelope glycoprotein hemagglutinin (HA), through shift and drift, permitting influenza to escape protection induced by current vaccines or natural immunity. Recently a new variant, H7N9, has emerged in China causing global concern. First, there have been more than 130 laboratory-confirmed human infections resulting in an alarmingly high death rate (32.3%). Second, genetic changes found in H7N9 appear to be associated with enabling avian influenza viruses to spread more effectively in mammals, thus transmitting infections on a larger scale. Currently, no vaccines or drugs are effectively able to target H7N9. Here, we report the rapid development of a synthetic consensus DNA vaccine (pH7HA) to elicit potent protective immunity against the H7N9 viruses. We show that pH7HA induces broad antibody responses that bind to divergent HAs from multiple new members of the H7N9 family. These antibody responses result in high-titer HAI against H7N9. Simultaneously, this vaccine induces potent polyfunctional effector CD4 and CD8T cell memory responses. Animals vaccinated with pH7HA are completely protected from H7N9 virus infection and any morbidity associated with lethal challenge. This study establishes that this synthetic consensus DNA vaccine represents a new tool for targeting emerging infection, and more importantly, its design, testing and development into seed stock for vaccine production in a few days in the pandemic setting has significant implications for the rapid deployment of vaccines protecting against emerging infectious diseases.

  17. Toxoplasma gondii GRA7-Induced TRAF6 Activation Contributes to Host Protective Immunity

    PubMed Central

    Yuk, Jae-Min; Lee, Young-Ha; Jo, Eun-Kyeong

    2015-01-01

    The intracellular parasite Toxoplasma gondii has unique dense granule antigens (GRAs) that are crucial for host infection. Emerging evidence suggests that GRA7 of T. gondii is a promising serodiagnostic marker and an effective toxoplasmosis vaccine candidate; however, little is known about the intracellular regulatory mechanisms involved in the GRA7-induced host responses. Here we show that GRA7-induced MyD88 signaling through the activation of TRAF6 and production of reactive oxygen species (ROS) is required for the induction of NF-κB-mediated proinflammatory responses by macrophages. GRA7 stimulation resulted in the rapid activation of mitogen-activated protein kinases and an early burst of ROS in macrophages in a MyD88-dependent manner. GRA7 induced a physical association between GRA7 and TRAF6 via MyD88. Remarkably, the C terminus of GRA7 (GRA7-V) was sufficient for interaction with and ubiquitination of the RING domain of TRAF6, which is capable of inflammatory cytokine production. Interestingly, the generation of ROS and TRAF6 activation are mutually dependent on GRA7/MyD88-mediated signaling in macrophages. Furthermore, mice immunized with GRA7-V showed markedly increased Th1 immune responses and protective efficacy against T. gondii infection. Collectively, these results provide novel insight into the crucial role of GRA7-TRAF6 signaling in innate immune responses. PMID:26553469

  18. Dengue virus type 1 DNA vaccine induces protective immune responses in rhesus macaques.

    PubMed

    Raviprakash, K; Porter, K R; Kochel, T J; Ewing, D; Simmons, M; Phillips, I; Murphy, G S; Weiss, W R; Hayes, C G

    2000-07-01

    A candidate DNA vaccine expressing dengue virus type 1 pre-membrane and envelope proteins was used to immunize rhesus macaques. Monkeys were immunized intramuscularly (i.m.) or intradermally (i.d.) by three or four 1 mg doses of vaccine, respectively. Monkeys that were inoculated i.m. seroconverted more quickly and had higher antibody levels than those that were inoculated i.d. The sera exhibited virus-neutralizing activity, which declined over time. Four of the eight i.m.-inoculated monkeys were protected completely from developing viraemia when challenged 4 months after the last dose with homologous dengue virus. The other four monkeys had reduced viraemia compared with the control immunized monkeys. The i.d. -inoculated monkeys showed no reduction in viraemia when challenged with the virus. All vaccinated monkeys showed an anamnestic antibody response, indicating that they had established immunological memory. Vaccine-induced antibody had an avidity index similar to that of antibody induced by virus infection; however, no clear correlation was apparent between antibody avidity and virus neutralization titres.

  19. Immunological responses and protective immunity in BCG vaccinated badgers following endobronchial infection with Mycobacterium bovis.

    PubMed

    Lesellier, Sandrine; Corner, Leigh; Costello, Eamon; Lyashchenko, Konstantin; Greenwald, Rena; Esfandiari, Javan; Singh, Mahavir; Hewinson, R Glyn; Chambers, Mark; Gormley, Eamonn

    2009-01-14

    European badgers (Meles meles) are a reservoir host of Mycobacterium bovis and are implicated in the transmission of tuberculosis to cattle in Ireland and Great Britain. The development of a vaccine for use in badgers is considered a key element of any campaign to eradicate the disease in livestock in both countries. In this study we have vaccinated groups of badgers with approximately 5 x 10(5)cfu of the BCG vaccine delivered via two alternative routes, subcutaneous and mucosal (intranasal/conjunctival). Following experimental endobronchial infection with approximately 10(4)cfu of M. bovis, all badgers were euthanised at 12 weeks post-infection. At post-mortem examination both vaccinated groups had significantly reduced severity of disease compared with the non-vaccinated controls. The analysis of immune responses throughout the study showed that vaccination with BCG did not generate any detectable immunological responses as measured by IFN-gamma production in antigen-stimulated peripheral blood mononuclear cells (PBMC) and IgG serological responses. However, the levels of the responses increased following M. bovis infection, and the kinetic profiles corresponded to the severity of lesions recorded post-mortem. Significant differences were observed in the timing of development of the immune responses between vaccinates and controls. The results suggest that the immunological responses are associated with the levels of protective immunity and could be used as markers to monitor control of disease in badgers following vaccination.

  20. Active immunizations with peptide-DC vaccines and passive transfer with antibodies protect neutropenic mice against disseminated candidiasis.

    PubMed

    Xin, Hong

    2016-01-01

    We previously report that peptide-pulsed dendritic cell (DC) vaccination, which targeting two peptides (Fba and Met6) expressed on the cell surface of Candida albicans, can induce high degree of protection against disseminated candidiasis in immunocompetent mice. Passive transfer of immune sera from the peptide immunized mice or peptide-related monoclonal antibodies demonstrated that protection was medicated by peptide-specific antibodies. In this study the efficacy of active and passive immunization against disseminated candidiasis was tested in mice with cyclophosphamide-induced neutropenia. Peptide-DC vaccines were given to mice prior to induction of neutropenia. We show active immunization with either Fba or Met6 peptide-DC vaccine significantly improved the survival and reduced the fungal burden of disseminated candidiasis in those immunocompromised mice. Importantly, we show that administration of two protective monoclonal antibodies also protect neutropenic mice against the disease, implying possibility of developing a successful passive immunotherapy strategy to treat the disease and protect against disseminated candidiasis. The results of this study are crucial as they address the fundamental questions as to whether the synthetic peptide vaccine induced immunity protects the host during a neutropenic episode. We anticipate that this peptide-vaccine study will serve as the foundation of future investigations into new peptide vaccines comprised of cell surface peptides from other medically important Candida species, as well as other fungi.

  1. Medawar's legacy to cellular immunology and clinical transplantation: a commentary on Billingham, Brent and Medawar (1956) 'Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance'.

    PubMed

    Simpson, Elizabeth

    2015-04-19

    'Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance', published in Philosophical Transactions B in 1956 by Peter Medawar and his colleagues, PhD graduate Leslie Brent and postdoctoral fellow Rupert Billingham, is a full description of the concept of acquired transplantation tolerance. Their 1953 Nature paper (Billingham RE et al. 1953 Nature 172, 603-606. (doi:10.1038/172603a0)) had provided initial evidence with experimental results from a small number of neonatal mice, with mention of similar findings in chicks. The Philosophical Transactions B 1956 paper is clothed with an astonishing amount of further experimental detail. It is written in Peter Medawar's landmark style: witty, perceptive and full of images that can be recalled even when details of the supporting information have faded. Those images are provided not just by a series of 20 colour plates showing skin graft recipient mice, rats, rabbits, chickens and duck, bearing fur or plumage of donor origin, but by his choice of metaphor, simile and analogy to express the questions being addressed and the interpretation of their results, along with those of relevant published data and his prescient ideas of what the results might portend. This work influenced both immunology researchers and clinicians and helped to lay the foundations for successful transplantation programmes. It led to the award of a Nobel prize in 1960 to Medawar, and subsequently to several scientists who advanced these areas. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society.

  2. Medawar's legacy to cellular immunology and clinical transplantation: a commentary on Billingham, Brent and Medawar (1956) ‘Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance’

    PubMed Central

    Simpson, Elizabeth

    2015-01-01

    ‘Quantitative studies on tissue transplantation immunity. III. Actively acquired tolerance’, published in Philosophical Transactions B in 1956 by Peter Medawar and his colleagues, PhD graduate Leslie Brent and postdoctoral fellow Rupert Billingham, is a full description of the concept of acquired transplantation tolerance. Their 1953 Nature paper (Billingham RE et al. 1953 Nature 172, 603–606. (doi:10.1038/172603a0)) had provided initial evidence with experimental results from a small number of neonatal mice, with mention of similar findings in chicks. The Philosophical Transactions B 1956 paper is clothed with an astonishing amount of further experimental detail. It is written in Peter Medawar's landmark style: witty, perceptive and full of images that can be recalled even when details of the supporting information have faded. Those images are provided not just by a series of 20 colour plates showing skin graft recipient mice, rats, rabbits, chickens and duck, bearing fur or plumage of donor origin, but by his choice of metaphor, simile and analogy to express the questions being addressed and the interpretation of their results, along with those of relevant published data and his prescient ideas of what the results might portend. This work influenced both immunology researchers and clinicians and helped to lay the foundations for successful transplantation programmes. It led to the award of a Nobel prize in 1960 to Medawar, and subsequently to several scientists who advanced these areas. This commentary was written to celebrate the 350th anniversary of the journal Philosophical Transactions of the Royal Society. PMID:25750245

  3. A Recombinant Chimeric Ad5/3 Vector Expressing a Multistage Plasmodium Antigen Induces Protective Immunity in Mice Using Heterologous Prime-Boost Immunization Regimens.

    PubMed

    Cabrera-Mora, Monica; Fonseca, Jairo Andres; Singh, Balwan; Zhao, Chunxia; Makarova, Natalia; Dmitriev, Igor; Curiel, David T; Blackwell, Jerry; Moreno, Alberto

    2016-10-01

    An ideal malaria vaccine should target several stages of the parasite life cycle and induce antiparasite and antidisease immunity. We have reported a Plasmodium yoelii chimeric multistage recombinant protein (P. yoelii linear peptide chimera/recombinant modular chimera), engineered to express several autologous T cell epitopes and sequences derived from the circumsporozoite protein and the merozoite surface protein 1. This chimeric protein elicits protective immunity, mediated by CD4(+) T cells and neutralizing Abs. However, experimental evidence, from pre-erythrocytic vaccine candidates and irradiated sporozoites, has shown that CD8(+) T cells play a significant role in protection. Recombinant viral vectors have been used as a vaccine platform to elicit effective CD8(+) T cell responses. The human adenovirus (Ad) serotype 5 has been tested in malaria vaccine clinical trials with excellent safety profile. Nevertheless, a major concern for the use of Ad5 is the high prevalence of anti-vector neutralizing Abs in humans, hampering its immunogenicity. To minimize the impact of anti-vector pre-existing immunity, we developed a chimeric Ad5/3 vector in which the knob region of Ad5 was replaced with that of Ad3, conferring partial resistance to anti-Ad5 neutralizing Abs. Furthermore, we implemented heterologous Ad/protein immunization regimens that include a single immunization with recombinant Ad vectors. Our data show that immunization with the recombinant Ad5/3 vector induces protective efficacy indistinguishable from that elicited by Ad5. Our study also demonstrates that the dose of the Ad vectors has an impact on the memory profile and protective efficacy. The results support further studies with Ad5/3 for malaria vaccine development. PMID:27574299

  4. Partial protective immunity against toxoplasmosis in mice elicited by recombinant Toxoplasma gondii malate dehydrogenase.

    PubMed

    Liu, Zhuanzhuan; Yuan, Fei; Yang, Yanping; Yin, Litian; Liu, Yisheng; Wang, Yanjuan; Zheng, Kuiyang; Cao, Jianping

    2016-02-10

    Toxoplasma gondii can infect humans and wildlife, sometimes causing serious clinical presentations. Currently, no viable vaccine or effective drug strategies exist to prevent and control toxoplasmosis. T. gondii malate dehydrogenase (TgMDH) is a crucial enzyme in cellular redox reactions and has been shown to be an immunogenic compound that could be a potential vaccine candidate. Here, we investigate the protective efficacy of recombinant TgMDH (rTgMDH) against T. gondii infection in BALB/c mice. All mice were vaccinated via the nasal route. We determined the optimal vaccination dose by monitoring systemic and mucosal immune responses. The results showed that mice vaccinated with 30 μg of rTgMDH produced the highest antibody titers in serum, a strong lymphoproliferative response, marked increases in their levels of IL-2 and IFN-γ, and significantly greater levels of specific secretory IgA (sIgA) in mucosal washes. In addition, the vaccinated mice were orally challenged with tachyzoites of the virulent T. gondii RH strain 2 weeks after the final vaccination. Compared to the control group, we found that vaccination with rTgMDH increased the survival rate of infected mice by 47% and also significantly reduced the tachyzoite loads in their liver (by 58%) and brain (by 41%). Therefore, the rTgMDH protein triggers a strong systemic and mucosal immune response and provides partial protection against T. gondii infection.

  5. Does childhood immunization against infectious diseases protect from the development of atopic disease?

    PubMed

    Martignon, Gilles; Oryszczyn, Marie-Pierre; Annesi-Maesano, Isabella

    2005-05-01

    The argument of whether early immunization against infections promotes allergy or protects from it is presently under debate. The relationship between childhood immunization and the development of atopic diseases (asthma, allergic rhinitis and eczema) was examined in a population-based sample of 718 adolescents by taking individual data drawn from personal paediatric records on the schedule and the type of vaccination into account. Atopic diseases were determined using a standardized questionnaire. After adjustment for sex, age, father's socioeconomic status and active smoking, adolescents having been vaccinated (n = 694) had a significant lower risk to suffer from asthma or atopic diseases than non-vaccinated adolescents did (n = 24) [odds ratio (OR) = 0.30; 95% CI: 0.10, 0.92]. The relationship did not depend on the disease against which the vaccine was used as prophylaxis, the observance of the vaccination schedule or the number of inoculations. A higher protection was observed in the case of live attenuated vaccines (oral poliomyelitis and bacilli Camille-Guerin; OR = 0.26; 95% CI: 0.08, 0.83). These results, in agreement with previous ecological data, support the hypothesis that early vaccines could promote Th1 proliferation in response to the infectious agent contained in it, which inhibits the enhancement of atopic manifestations. Further studies are needed to confirm the phenomenon.

  6. Immune history profoundly affects broadly protective B cell responses to influenza.

    PubMed

    Andrews, Sarah F; Huang, Yunping; Kaur, Kaval; Popova, Lyubov I; Ho, Irvin Y; Pauli, Noel T; Henry Dunand, Carole J; Taylor, William M; Lim, Samuel; Huang, Min; Qu, Xinyan; Lee, Jane-Hwei; Salgado-Ferrer, Marlene; Krammer, Florian; Palese, Peter; Wrammert, Jens; Ahmed, Rafi; Wilson, Patrick C

    2015-12-01

    Generating a broadly protective influenza vaccine is critical to global health. Understanding how immune memory influences influenza immunity is central to this goal. We undertook an in-depth study of the B cell response to the pandemic 2009 H1N1 vaccine over consecutive years. Analysis of monoclonal antibodies generated from vaccine-induced plasmablasts demonstrated that individuals with low preexisting serological titers to the vaccinating strain generated a broadly reactive, hemagglutinin (HA) stalk-biased response. Higher preexisting serum antibody levels correlated with a strain-specific HA head-dominated response. We demonstrate that this HA head immunodominance encompasses poor accessibility of the HA stalk epitopes. Further, we show polyreactivity of HA stalk-reactive antibodies that could cause counterselection of these cells. Thus, preexisting memory B cells against HA head epitopes predominate, inhibiting a broadly protective response against the HA stalk upon revaccination with similar strains. Consideration of influenza exposure history is critical for new vaccine strategies designed to elicit broadly neutralizing antibodies. PMID:26631631

  7. Immune history profoundly affects broadly protective B cell responses to influenza

    PubMed Central

    Andrews, Sarah F.; Huang, Yunping; Kaur, Kaval; Popova, Lyubov I.; Ho, Irvin Y.; Pauli, Noel T.; Dunand, Carole J. Henry; Taylor, William M; Lim, Samuel; Huang, Min; Qu, Xinyan; Lee, Jane-Hwei; Salgado-Ferrer, Marlene; Krammer, Florian; Palese, Peter; Wrammert, Jens; Ahmed, Rafi; Wilson, Patrick C.

    2016-01-01

    Generating a broadly protective influenza vaccine is critical to global health. Understanding how immune memory influences influenza immunity is central to this goal. We undertook an in-depth study of the B cell response to the pandemic 2009 H1N1 vaccine over consecutive years. Analysis of monoclonal Abs generated from vaccine-induced plasmablasts demonstrated that individuals with low preexisting serological titers to the vaccinating strain generated a broadly reactive, HA stalk-biased, response. Higher preexisting serum antibody levels correlated with a strain-specific HA head-dominated response. We demonstrate that this HA head immunodominance encompasses poor accessibility of the HA stalk epitopes. Further, we show polyreactivity of HA stalk-reactive antibodies that could cause counterselection of these cells. Thus, preexisting memory against HA head epitopes predominate, inhibiting a broadly protective response against the HA stalk upon revaccination with similar strains. Consideration of influenza exposure history is critical for new vaccine strategies designed to elicit broadly neutralizing antibodies. PMID:26631631

  8. Protective effects of HemoHIM on immune and hematopoietic systems against γ-irradiation.

    PubMed

    Park, Hae-Ran; Jo, Sung-Kee; Jung, Uhee; Yee, Sung-Tae; Kim, Sung-Ho

    2014-02-01

    We examined the effect of HemoHIM on the protective efficacy of hematopoietic stem cells and on the recovery of immune cells against sublethal doses of ionizing radiation. Two-month-old mice were exposed to γ-rays at a dose of 8, 6.5, or 5 Gy for a30-day survival study, endogenous spleen colony formation, or other experiments, respectively. HemoHIM was injected intraperitoneally before and after irradiation. Our results showed that HemoHIM significantly decreased the mortality of sublethally irradiated mice. The HemoHIM administration decreased the apoptosis of bone marrow cells in irradiated mice. On the other hand, HemoHIM increased the formation of endogenous spleen colony in irradiated mice. In irradiated mice, the recovery of total leukocytes in the peripheral blood and lymphocytes in the spleen were enhanced significantly by HemoHIM. Moreover, the function of B cells, T cells, and NK cells regenerated in irradiated mice were significantly improved by the administration of HemoHIM. HemoHIM showed an ideal radioprotector for protecting hematopoietic stem cells and for accelerating the recovery of immune cells. We propose HemoHIM as a beneficial supplement drug during radiotherapy to alleviate adverse radiation-induced effects for cancer patients. PMID:23595637

  9. Recombinant Flagellin-Porcine Circovirus Type 2 Cap Fusion Protein Promotes Protective Immune Responses in Mice

    PubMed Central

    Zhang, Chunyan; Zhu, Shanshan; Wei, Li; Yan, Xu; Wang, Jing; Quan, Rong; She, Ruiping; Hu, Fengjiao; Liu, Jue

    2015-01-01

    The Cap protein of porcine circovirus type 2 (PCV2) that serves as a major host-protective immunogen was used to develop recombinant vaccines for control of PCV2-associated diseases. Growing research data have demonstrated the high effectiveness of flagellin as an adjuvant for humoral and cellular immune responses. Here, a recombinant protein was designed by fusing a modified version of bacterial flagellin to PCV2 Cap protein and expressed in a baculovirus system. When administered without adjuvant to BALB/c mice, the flagellin-Cap fusion protein elicited stronger PCV2-specific IgG antibody response, higher neutralizing antibody levels, milder histopathological changes and lower viremia, as well as higher secretion of cytokines such as TNF-α and IFN-γ that conferred better protection against virus challenge than those in the recombinant Cap alone-inoculated mice. These results suggest that the recombinant Cap protein when fused to flagellin could elicit better humoral and cellular immune responses against PCV2 infection in a mouse model, thereby acting as an attractive candidate vaccine for control of the PCV2-associated diseases. PMID:26070075

  10. Protective effects of HemoHIM on immune and hematopoietic systems against γ-irradiation.

    PubMed

    Park, Hae-Ran; Jo, Sung-Kee; Jung, Uhee; Yee, Sung-Tae; Kim, Sung-Ho

    2014-02-01

    We examined the effect of HemoHIM on the protective efficacy of hematopoietic stem cells and on the recovery of immune cells against sublethal doses of ionizing radiation. Two-month-old mice were exposed to γ-rays at a dose of 8, 6.5, or 5 Gy for a30-day survival study, endogenous spleen colony formation, or other experiments, respectively. HemoHIM was injected intraperitoneally before and after irradiation. Our results showed that HemoHIM significantly decreased the mortality of sublethally irradiated mice. The HemoHIM administration decreased the apoptosis of bone marrow cells in irradiated mice. On the other hand, HemoHIM increased the formation of endogenous spleen colony in irradiated mice. In irradiated mice, the recovery of total leukocytes in the peripheral blood and lymphocytes in the spleen were enhanced significantly by HemoHIM. Moreover, the function of B cells, T cells, and NK cells regenerated in irradiated mice were significantly improved by the administration of HemoHIM. HemoHIM showed an ideal radioprotector for protecting hematopoietic stem cells and for accelerating the recovery of immune cells. We propose HemoHIM as a beneficial supplement drug during radiotherapy to alleviate adverse radiation-induced effects for cancer patients.

  11. Oral Immunization of Mice with Live Pneumocystis murina Protects against Pneumocystis Pneumonia.

    PubMed

    Samuelson, Derrick R; de la Rua, Nicholas M; Charles, Tysheena P; Ruan, Sanbao; Taylor, Christopher M; Blanchard, Eugene E; Luo, Meng; Ramsay, Alistair J; Shellito, Judd E; Welsh, David A

    2016-03-15

    Pneumocystis pneumonia is a major cause of morbidity and mortality in immunocompromised patients, particularly those infected with HIV. In this study, we evaluated the potential of oral immunization with live Pneumocystis to elicit protection against respiratory infection with Pneumocystis murina. C57BL/6 mice vaccinated with live P. murina using a prime-boost vaccination strategy were protected from a subsequent lung challenge with P. murina at 2, 7, 14, and 28 d postinfection even after CD4(+) T cell depletion. Specifically, vaccinated immunocompetent mice had significantly faster clearance than unvaccinated immunocompetent mice and unvaccinated CD4-depleted mice remained persistently infected with P. murina. Vaccination also increased numbers of CD4(+) T cells, CD8(+) T cells, CD19(+) B cells, and CD11b(+) macrophages in the lungs following respiratory infection. In addition, levels of lung, serum, and fecal P. murina-specific IgG and IgA were increased in vaccinated animals. Furthermore, administration of serum from vaccinated mice significantly reduced Pneumocystis lung burden in infected animals compared with control serum. We also found that the diversity of the intestinal microbial community was altered by oral immunization with P. murina. To our knowledge, our data demonstrate for the first time that an oral vaccination strategy prevents Pneumocystis infection.

  12. Immunization with the MAEBL M2 Domain Protects against Lethal Plasmodium yoelii Infection.

    PubMed

    Leite, Juliana A; Bargieri, Daniel Y; Carvalho, Bruna O; Albrecht, Letusa; Lopes, Stefanie C P; Kayano, Ana Carolina A V; Farias, Alessandro S; Chia, Wan Ni; Claser, Carla; Malleret, Benoit; Russell, Bruce; Castiñeiras, Catarina; Santos, Leonilda M B; Brocchi, Marcelo; Wunderlich, Gerhard; Soares, Irene S; Rodrigues, Mauricio M; Rénia, Laurent; Costa, Fabio T M

    2015-10-01

    Malaria remains a world-threatening disease largely because of the lack of a long-lasting and fully effective vaccine. MAEBL is a type 1 transmembrane molecule with a chimeric cysteine-rich ectodomain homologous to regions of the Duffy binding-like erythrocyte binding protein and apical membrane antigen 1 (AMA1) antigens. Although MAEBL does not appear to be essential for the survival of blood-stage forms, ectodomains M1 and M2, homologous to AMA1, seem to be involved in parasite attachment to erythrocytes, especially M2. MAEBL is necessary for sporozoite infection of mosquito salivary glands and is expressed in liver stages. Here, the Plasmodium yoelii MAEBL-M2 domain was expressed in a prokaryotic vector. C57BL/6J mice were immunized with doses of P. yoelii recombinant protein rPyM2-MAEBL. High levels of antibodies, with balanced IgG1 and IgG2c subclasses, were achieved. rPyM2-MAEBL antisera were capable of recognizing the native antigen. Anti-MAEBL antibodies recognized different MAEBL fragments expressed in CHO cells, showing stronger IgM and IgG responses to the M2 domain and repeat region, respectively. After a challenge with P. yoelii YM (lethal strain)-infected erythrocytes (IE), up to 90% of the immunized animals survived and a reduction of parasitemia was observed. Moreover, splenocytes harvested from immunized animals proliferated in a dose-dependent manner in the presence of rPyM2-MAEBL. Protection was highly dependent on CD4(+), but not CD8(+), T cells toward Th1. rPyM2-MAEBL antisera were also able to significantly inhibit parasite development, as observed in ex vivo P. yoelii erythrocyte invasion assays. Collectively, these findings support the use of MAEBL as a vaccine candidate and open perspectives to understand the mechanisms involved in protection. PMID:26169268

  13. Recombinant tandem multi-linear neutralizing epitopes of human enterovirus 71 elicited protective immunity in mice

    PubMed Central

    2014-01-01

    Background Human Enterovirus 71 (EV71) has emerged as the leading cause of viral encephalitis in children, especially in the Asia-Pacific regions. EV71 vaccine development is of high priority at present, and neutralization antibodies have been documented to play critical roles during in vitro and in vivo protection against EV71 infection. Results In this study, a novel strategy to produce EV71 vaccine candidate based on recombinant multiple tandem linear neutralizing epitopes (mTLNE) was proposed. The three well identified EV71 linear neutralizing epitopes in capsid proteins, VP1-SP55, VP1-SP70 and VP2-SP28, were sequentially linked by a Gly-Ser linker ((G4S)3), and expressed in E.coli in fusion with the Trx and His tag at either terminal. The recombinant protein mTLNE was soluble and could be purified by standard affinity chromatography. Following three dosage of immunization in adult mice, EV71-specific IgG and neutralization antibodies were readily induced by recombinant mTLNE. IgG subtyping demonstrated that lgG1 antibodies dominated the mTLNE-induced humoral immune response. Especially, cytokine profiling in spleen cells from the mTLNE-immunized mice revealed high production of IL-4 and IL-6. Finally, in vivo challenge experiments showed that passive transfer with anti-mTLNE sera conferred full protection against lethal EV71 challenge in neonatal mice. Conclusion Our results demonstrated that this rational designed recombinant mTLNE might have the potential to be further developed as an EV71 vaccine in the future. PMID:24885030

  14. Mucosal Immunization with Iron Receptor Antigens Protects against Urinary Tract Infection

    PubMed Central

    Smith, Sara N.; Mobley, Harry L. T.

    2009-01-01

    Uncomplicated infections of the urinary tract, caused by uropathogenic Escherichia coli, are among the most common diseases requiring medical intervention. A preventive vaccine to reduce the morbidity and fiscal burden these infections have upon the healthcare system would be beneficial. Here, we describe the results of a large-scale selection process that incorporates bioinformatic, genomic, transcriptomic, and proteomic screens to identify six vaccine candidates from the 5379 predicted proteins encoded by uropathogenic E. coli strain CFT073. The vaccine candidates, ChuA, Hma, Iha, IreA, IroN, and IutA, all belong to a functional class of molecules that is involved in iron acquisition, a process critical for pathogenesis in all microbes. Intranasal immunization of CBA/J mice with these outer membrane iron receptors elicited a systemic and mucosal immune response that included the production of antigen-specific IgM, IgG, and IgA antibodies. The cellular response to vaccination was characterized by the induction and secretion of IFN-γ and IL-17. Of the six potential vaccine candidates, IreA, Hma, and IutA provided significant protection from experimental infection. In immunized animals, class-switching from IgM to IgG and production of antigen-specific IgA in the urine represent immunological correlates of protection from E. coli bladder colonization. These findings are an important first step toward the development of a subunit vaccine to prevent urinary tract infections and demonstrate how targeting an entire class of molecules that are collectively required for pathogenesis may represent a fundamental strategy to combat infections. PMID:19806177

  15. Immunization with the MAEBL M2 Domain Protects against Lethal Plasmodium yoelii Infection

    PubMed Central

    Leite, Juliana A.; Bargieri, Daniel Y.; Carvalho, Bruna O.; Albrecht, Letusa; Lopes, Stefanie C. P.; Kayano, Ana Carolina A. V.; Farias, Alessandro S.; Chia, Wan Ni; Claser, Carla; Malleret, Benoit; Russell, Bruce; Castiñeiras, Catarina; Santos, Leonilda M. B.; Brocchi, Marcelo; Wunderlich, Gerhard; Soares, Irene S.; Rodrigues, Mauricio M.; Rénia, Laurent

    2015-01-01

    Malaria remains a world-threatening disease largely because of the lack of a long-lasting and fully effective vaccine. MAEBL is a type 1 transmembrane molecule with a chimeric cysteine-rich ectodomain homologous to regions of the Duffy binding-like erythrocyte binding protein and apical membrane antigen 1 (AMA1) antigens. Although MAEBL does not appear to be essential for the survival of blood-stage forms, ectodomains M1 and M2, homologous to AMA1, seem to be involved in parasite attachment to erythrocytes, especially M2. MAEBL is necessary for sporozoite infection of mosquito salivary glands and is expressed in liver stages. Here, the Plasmodium yoelii MAEBL-M2 domain was expressed in a prokaryotic vector. C57BL/6J mice were immunized with doses of P. yoelii recombinant protein rPyM2-MAEBL. High levels of antibodies, with balanced IgG1 and IgG2c subclasses, were achieved. rPyM2-MAEBL antisera were capable of recognizing the native antigen. Anti-MAEBL antibodies recognized different MAEBL fragments expressed in CHO cells, showing stronger IgM and IgG responses to the M2 domain and repeat region, respectively. After a challenge with P. yoelii YM (lethal strain)-infected erythrocytes (IE), up to 90% of the immunized animals survived and a reduction of parasitemia was observed. Moreover, splenocytes harvested from immunized animals proliferated in a dose-dependent manner in the presence of rPyM2-MAEBL. Protection was highly dependent on CD4+, but not CD8+, T cells toward Th1. rPyM2-MAEBL antisera were also able to significantly inhibit parasite development, as observed in ex vivo P. yoelii erythrocyte invasion assays. Collectively, these findings support the use of MAEBL as a vaccine candidate and open perspectives to understand the mechanisms involved in protection. PMID:26169268

  16. NDV-3 protects mice from vulvovaginal candidiasis through T- and B-cell immune response.

    PubMed

    Ibrahim, Ashraf S; Luo, Guanpingsheng; Gebremariam, Teclegiorgis; Lee, Hongkyu; Schmidt, Clint S; Hennessey, John P; French, Samuel W; Yeaman, Michael R; Filler, Scott G; Edwards, John E

    2013-11-12

    We have previously reported that vaccination with rAls3p-N protein of Candida albicans, formulated with alum adjuvant (also designated as NDV-3) protects immunocompetent mice from, lethal disseminated candidiasis and mucosal oropharyngeal candidiasis. NDV-3 vaccine was recently, tested in a Phase 1 clinical trial and found to be safe, well-tolerated, and induced robust humoral and, cellular immune responses with increased interferon (IFN)-gamma and interleukin (IL)-17 secretion. In preparation for a Phase 2 clinical trial against vulvovaginal candidiasis (VVC), we evaluated NDV-3, efficacy in a murine VVC model. Here, NDV-3 induced a strong immune response characterized by high, anti-rAls3p-N serum IgG and vaginal IgA titers. Furthermore, moderate doses of the vaccine (a range of 1-30μg given subcutaneously [SQ] or 0.3-10μg given intramuscularly [IM]) elicited a 10-1000 fold, decrease in vaginal fungal burden vs. control (mice injected with alum adjuvant alone) in both inbred, and outbred mice infected with different clinical C. albicans isolates. Additionally, NDV-3 required both, T and B lymphocytes for efficacy in reducing C. albicans tissue burden, which is followed by a reduction, in neutrophil influx to the affected site. Finally, anti-rAls3p-N antibodies enhanced the ex vivo killing, of C. albicans by neutrophils primed with IFN-gamma. These data indicate that NDV-3 protects mice, from VVC by a mechanism that involves the concerted priming of both humoral and adaptive immune, responses.

  17. Measurement of sunscreen immune protection factors in humans: a consensus paper.

    PubMed

    Fourtanier, Anny; Moyal, Dominique; Maccario, Jean; Compan, Delphine; Wolf, Peter; Quehenberger, Franz; Cooper, Kevin; Baron, Elma; Halliday, Gary; Poon, Terrence; Seed, Paul; Walker, Susan L; Young, Antony R

    2005-09-01

    It is increasingly accepted that sunscreens should protect against ultraviolet radiation (UVR)-induced immunosuppression, with an index of protection that can be compared with the sun protection factor (SPF). Five groups of immunoprotection researchers met to discuss the status of immune protection factor (IPF) evaluation in human skin in vivo. Current methods rely on a suncreen's inhibition of UVR-induced local suppression of the contact hypersensitivity (CHS) response or the delayed-type hypersensitivity (DTH) response, using either the induction or the elicitation arms of these responses. The induction arm of the CHS response has the advantage of being sensitive to a single sub-erythemal exposure of solar-simulating radiation (SSR) that allows a direct comparison with the SPF. This approach, which necessitates sensitization, requires a large number of volunteers and is too labor intensive and time consuming to become a routine method. The elicitation arm of the CHS or DTH responses exploits prior sensitization to contact or recall antigens and has the advantage of being possible to apply on small groups of volunteers. Some current protocols, however, require repeat SSR exposures, which invalidates a direct comparison with SPF that is based on a single exposure. There is a need for a new simpler method of IPF that will have to be validated against existing models. PMID:16117779

  18. Biofilm Matrix Exoproteins Induce a Protective Immune Response against Staphylococcus aureus Biofilm Infection

    PubMed Central

    Gil, Carmen; Solano, Cristina; Burgui, Saioa; Latasa, Cristina; García, Begoña; Toledo-Arana, Alejandro

    2014-01-01

    The Staphylococcus aureus biofilm mode of growth is associated with several chronic infections that are very difficult to treat due to the recalcitrant nature of biofilms to clearance by antimicrobials. Accordingly, there is an increasing interest in preventing the formation of S. aureus biofilms and developing efficient antibiofilm vaccines. Given the fact that during a biofilm-associated infection, the first primary interface between the host and the bacteria is the self-produced extracellular matrix, in this study we analyzed the potential of extracellular proteins found in the biofilm matrix to induce a protective immune response against S. aureus infections. By using proteomic approaches, we characterized the exoproteomes of exopolysaccharide-based and protein-based biofilm matrices produced by two clinical S. aureus strains. Remarkably, results showed that independently of the nature of the biofilm matrix, a common core of secreted proteins is contained in both types of exoproteomes. Intradermal administration of an exoproteome extract of an exopolysaccharide-dependent biofilm induced a humoral immune response and elicited the production of interleukin 10 (IL-10) and IL-17 in mice. Antibodies against such an extract promoted opsonophagocytosis and killing of S. aureus. Immunization with the biofilm matrix exoproteome significantly reduced the number of bacterial cells inside a biofilm and on the surrounding tissue, using an in vivo model of mesh-associated biofilm infection. Furthermore, immunized mice also showed limited organ colonization by bacteria released from the matrix at the dispersive stage of the biofilm cycle. Altogether, these data illustrate the potential of biofilm matrix exoproteins as a promising candidate multivalent vaccine against S. aureus biofilm-associated infections. PMID:24343648

  19. CD47 Promotes Protective Innate and Adaptive Immunity in a Mouse Model of Disseminated Candidiasis

    PubMed Central

    Navarathna, Dhammika H. M. L. P.; Stein, Erica V.; Lessey-Morillon, Elizabeth C.; Nayak, Debasis; Martin-Manso, Gema; Roberts, David D.

    2015-01-01

    CD47 is a widely expressed receptor that regulates immunity by engaging its counter-receptor SIRPα on phagocytes and its secreted ligand thrombospondin-1. Mice lacking CD47 can exhibit enhanced or impaired host responses to bacterial pathogens, but its role in fungal immunity has not been examined. cd47-/- mice on a C57BL/6 background showed significantly increased morbidity and mortality following Candida albicans infection when compared with wild-type mice. Despite normal fungal colonization at earlier times, cd47-/- mice at four days post-infection had increased colonization of brain and kidneys accompanied by stronger inflammatory reactions. Neutrophil and macrophage numbers were significantly elevated in kidneys and neutrophils in the brains of infected cd47-/- mice. However, no defect in phagocytic activity towards C. albicans was observed in cd47-/- bone-marrow-derived macrophages, and neutrophil and macrophage killing of C. albicans was not impaired. CD47-deficiency did not alter the early humoral immune response to C. albicans. Th1, Th2, and Th17 population of CD4+ T cells were expanded in the spleen, and gene expression profiles of spleen and kidney showed stronger pro-inflammatory signaling in infected cd47-/- mice. The chemoattractant chemokines MIP-2α and MIP-2β were highly expressed in infected spleens of cd47-/- mice. G-CSF, GM-CSF, and the inflammasome component NLRP3 were more highly expressed in infected cd47-/- kidneys than in infected wild-type controls. Circulating pro- (TNF-α, IL-6) and anti-inflammatory cytokines (IL-10) were significantly elevated, but IL-17 was decreased. These data indicate that CD47 plays protective roles against disseminated candidiasis and alters pro-inflammatory and immunosuppressive pathways known to regulate innate and T cell immunity. PMID:26010544

  20. Mutual Interference between Cytomegalovirus and Reconstitution of Protective Immunity after Hematopoietic Cell Transplantation.

    PubMed

    Reddehase, Matthias J

    2016-01-01

    Hematopoietic cell transplantation (HCT) is a therapy option for aggressive forms of hematopoietic malignancies that are resistant to standard antitumoral therapies. Hematoablative treatment preceding HCT, however, opens a "window of opportunity" for latent Cytomegalovirus (CMV) by releasing it from immune control with the consequence of reactivation of productive viral gene expression and recurrence of infectious virus. A "window of opportunity" for the virus represents a "window of risk" for the patient. In the interim between HCT and reconstitution of antiviral immunity, primarily mediated by CD8(+) T cells, initially low amounts of reactivated virus can expand exponentially, disseminate to essentially all organs, and cause multiple organ CMV disease, with interstitial pneumonia (CMV-IP) representing the most severe clinical manifestation. Here, I will review predictions originally made in the mouse model of experimental HCT and murine CMV infection, some of which have already paved the way to translational preclinical research and promising clinical trials of a preemptive cytoimmunotherapy of human CMV disease. Specifically, the mouse model has been pivotal in providing "proof of concept" for preventing CMV disease after HCT by adoptive transfer of preselected, virus epitope-specific effector and memory CD8(+) T cells bridging the critical interim. However, CMV is not a "passive antigen" but is a pathogen that actively interferes with the reconstitution of protective immunity by infecting bone marrow (BM) stromal cells that otherwise form niches for hematopoiesis by providing the structural microenvironment and by producing hematopoietically active cytokines, the hemopoietins. Depending on the precise conditions of HCT, reduced homing of transplanted hematopoietic stem- and progenitor cells to infected BM stroma and impaired colony growth and lineage differentiation can lead to "graft failure." In consequence, uncontrolled virus spread causes morbidity and

  1. CD47 Promotes Protective Innate and Adaptive Immunity in a Mouse Model of Disseminated Candidiasis.

    PubMed

    Navarathna, Dhammika H M L P; Stein, Erica V; Lessey-Morillon, Elizabeth C; Nayak, Debasis; Martin-Manso, Gema; Roberts, David D

    2015-01-01

    CD47 is a widely expressed receptor that regulates immunity by engaging its counter-receptor SIRPα on phagocytes and its secreted ligand thrombospondin-1. Mice lacking CD47 can exhibit enhanced or impaired host responses to bacterial pathogens, but its role in fungal immunity has not been examined. cd47-/- mice on a C57BL/6 background showed significantly increased morbidity and mortality following Candida albicans infection when compared with wild-type mice. Despite normal fungal colonization at earlier times, cd47-/- mice at four days post-infection had increased colonization of brain and kidneys accompanied by stronger inflammatory reactions. Neutrophil and macrophage numbers were significantly elevated in kidneys and neutrophils in the brains of infected cd47-/- mice. However, no defect in phagocytic activity towards C. albicans was observed in cd47-/- bone-marrow-derived macrophages, and neutrophil and macrophage killing of C. albicans was not impaired. CD47-deficiency did not alter the early humoral immune response to C. albicans. Th1, Th2, and Th17 population of CD4+ T cells were expanded in the spleen, and gene expression profiles of spleen and kidney showed stronger pro-inflammatory signaling in infected cd47-/- mice. The chemoattractant chemokines MIP-2α and MIP-2β were highly expressed in infected spleens of cd47-/- mice. G-CSF, GM-CSF, and the inflammasome component NLRP3 were more highly expressed in infected cd47-/- kidneys than in infected wild-type controls. Circulating pro- (TNF-α, IL-6) and anti-inflammatory cytokines (IL-10) were significantly elevated, but IL-17 was decreased. These data indicate that CD47 plays protective roles against disseminated candidiasis and alters pro-inflammatory and immunosuppressive pathways known to regulate innate and T cell immunity.

  2. Proteomic Identification of saeRS-Dependent Targets Critical for Protective Humoral Immunity against Staphylococcus aureus Skin Infection.

    PubMed

    Zhao, Fan; Cheng, Brian L; Boyle-Vavra, Susan; Alegre, Maria-Luisa; Daum, Robert S; Chong, Anita S; Montgomery, Christopher P

    2015-09-01

    Recurrent Staphylococcus aureus skin and soft tissue infections (SSTIs) are common despite detectable antibody responses, leading to the belief that the immune response elicited by these infections is not protective. We recently reported that S. aureus USA300 SSTI elicits antibodies that protect against recurrent SSTI in BALB/c but not C57BL/6 mice, and in this study, we aimed to uncover the specificity of the protective antibodies. Using a proteomic approach, we found that S. aureus SSTI elicited broad polyclonal antibody responses in both BALB/c and C57BL/6 mice and identified 10 S. aureus antigens against which antibody levels were significantly higher in immune BALB/c serum. Four of the 10 antigens identified are regulated by the saeRS operon, suggesting a dominant role for saeRS in protection. Indeed, infection with USA300Δsae failed to protect against secondary SSTI with USA300, despite eliciting a strong polyclonal antibody response against antigens whose expression is not regulated by saeRS. Moreover, the antibody repertoire after infection with USA300Δsae lacked antibodies specific for 10 saeRS-regulated antigens, suggesting that all or a subset of these antigens are necessary to elicit protective immunity. Infection with USA300Δhla elicited modest protection against secondary SSTI, and complementation of USA300Δsae with hla restored protection but incompletely. Together, these findings support a role for both Hla and other saeRS-regulated antigens in eliciting protection and suggest that host differences in immune responses to saeRS-regulated antigens may determine whether S. aureus infection elicits protective or nonprotective immunity against recurrent infection.

  3. Proteomic Identification of saeRS-Dependent Targets Critical for Protective Humoral Immunity against Staphylococcus aureus Skin Infection

    PubMed Central

    Zhao, Fan; Cheng, Brian L.; Boyle-Vavra, Susan; Alegre, Maria-Luisa; Daum, Robert S.; Chong, Anita S.

    2015-01-01

    Recurrent Staphylococcus aureus skin and soft tissue infections (SSTIs) are common despite detectable antibody responses, leading to the belief that the immune response elicited by these infections is not protective. We recently reported that S. aureus USA300 SSTI elicits antibodies that protect against recurrent SSTI in BALB/c but not C57BL/6 mice, and in this study, we aimed to uncover the specificity of the protective antibodies. Using a proteomic approach, we found that S. aureus SSTI elicited broad polyclonal antibody responses in both BALB/c and C57BL/6 mice and identified 10 S. aureus antigens against which antibody levels were significantly higher in immune BALB/c serum. Four of the 10 antigens identified are regulated by the saeRS operon, suggesting a dominant role for saeRS in protection. Indeed, infection with USA300Δsae failed to protect against secondary SSTI with USA300, despite eliciting a strong polyclonal antibody response against antigens whose expression is not regulated by saeRS. Moreover, the antibody repertoire after infection with USA300Δsae lacked antibodies specific for 10 saeRS-regulated antigens, suggesting that all or a subset of these antigens are necessary to elicit protective immunity. Infection with USA300Δhla elicited modest protection against secondary SSTI, and complementation of USA300Δsae with hla restored protection but incompletely. Together, these findings support a role for both Hla and other saeRS-regulated antigens in eliciting protection and suggest that host differences in immune responses to saeRS-regulated antigens may determine whether S. aureus infection elicits protective or nonprotective immunity against recurrent infection. PMID:26169277

  4. Antiradiation UV Vaccine: UV Radiation, Biological effects, lesions and medical management - immune-therapy and immune-protection.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key Words: Ultraviolet radiation,Standard Erythema Dose(SED), Minimal Erythema Dose(MED), Sun Burns, Solar Dermatitis, Sun Burned Disease, DNA Damage,Cell Damage, Antiradiation UV Vaccine, Immune-Prophylaxis of Sun Burned Diseases, Immune-Prophylaxis of Sun Burns, Immune-Therapy of Sun-Burned Disease and Sun Burns,Basal Cell Carcinoma (BCC), Squamous Cell Carcinoma (SCC), Toxic Epidermal Necrolysis(TEN). Introduction: High doses of UV generated by solar source and artificial sources create an exposure of mammals and other species which can lead to ultraviolet(UV)radiation- associated disease (including erythema, epilation, keratitis, etc.). UV radiation belongs to the non-ionizing part of the electromagnetic spectrum and ranges between 100 nm and 400 nm with 100 nm having been chosen arbitrarily as the boundary between non-ionizing and ionizing radiation, however EMR is a spectrum and UV can produce molecular ionization. UV radiation is conventionally categorized into 3 areas: UV-A (>315-400 nm),UV-B (>280-315 nm)and UV-C (>100-280 nm) [IARC,Working Group Reports,2005] An important consequence of stratospheric ozone depletion is the increased transmission of solar ultraviolet (UV)radiation to the Earth's lower atmosphere and surface. Stratospheric ozone levels have been falling, in certain areas, for the past several decades, so current surface ultraviolet-B (UV-B) radiation levels are thought to be close to their modern day maximum. [S.Madronich et al.1998] Overexposure of ultraviolet radiation a major cause of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) { collectively referred to as “non-melanoma" skin cancer (NMSC) and melanoma as well, with skin cancers being the most common cancer in North America. [Armstrong et al. 1993, Gallagher et al. 2005] Methods and Experimental Design: Our experiments and testing of a novel UV “Antiradiation Vaccine” have employed a wide variety of laboratory animals which include : Chinchilla

  5. Antiradiation UV Vaccine: UV Radiation, Biological effects, lesions and medical management - immune-therapy and immune-protection.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key Words: Ultraviolet radiation,Standard Erythema Dose(SED), Minimal Erythema Dose(MED), Sun Burns, Solar Dermatitis, Sun Burned Disease, DNA Damage,Cell Damage, Antiradiation UV Vaccine, Immune-Prophylaxis of Sun Burned Diseases, Immune-Prophylaxis of Sun Burns, Immune-Therapy of Sun-Burned Disease and Sun Burns,Basal Cell Carcinoma (BCC), Squamous Cell Carcinoma (SCC), Toxic Epidermal Necrolysis(TEN). Introduction: High doses of UV generated by solar source and artificial sources create an exposure of mammals and other species which can lead to ultraviolet(UV)radiation- associated disease (including erythema, epilation, keratitis, etc.). UV radiation belongs to the non-ionizing part of the electromagnetic spectrum and ranges between 100 nm and 400 nm with 100 nm having been chosen arbitrarily as the boundary between non-ionizing and ionizing radiation, however EMR is a spectrum and UV can produce molecular ionization. UV radiation is conventionally categorized into 3 areas: UV-A (>315-400 nm),UV-B (>280-315 nm)and UV-C (>100-280 nm) [IARC,Working Group Reports,2005] An important consequence of stratospheric ozone depletion is the increased transmission of solar ultraviolet (UV)radiation to the Earth's lower atmosphere and surface. Stratospheric ozone levels have been falling, in certain areas, for the past several decades, so current surface ultraviolet-B (UV-B) radiation levels are thought to be close to their modern day maximum. [S.Madronich et al.1998] Overexposure of ultraviolet radiation a major cause of skin cancer including basal cell carcinoma (BCC), squamous cell carcinoma (SCC) { collectively referred to as “non-melanoma" skin cancer (NMSC) and melanoma as well, with skin cancers being the most common cancer in North America. [Armstrong et al. 1993, Gallagher et al. 2005] Methods and Experimental Design: Our experiments and testing of a novel UV “Antiradiation Vaccine” have employed a wide variety of laboratory animals which include : Chinchilla

  6. Immunization of Mice With Vibrio cholerae Outer-Membrane Vesicles Protects Against Hyperinfectious Challenge and Blocks Transmission

    PubMed Central

    Bishop, Anne L.; Tarique, Abdullah A.; Patimalla, Bharathi; Calderwood, Stephen B.; Qadri, Firdausi

    2012-01-01

    Background. Vibrio cholerae excreted by cholera patients is “hyperinfectious” (HI), which can be modeled by passage through infant mice. Immunization of adult female mice with V. cholerae outer-membrane vesicles (OMVs) passively protects suckling mice from challenge. Although V. cholerae is unable to colonize protected pups, the bacteria survive passage and have the potential to be transmitted to susceptible individuals. Here, we investigated the impact of OMV immunization and the HI state on V. cholerae transmission. Methods. Neonatal mice suckled by OMV- or sham-immunized dams were challenged with HI V. cholerae. The infectivity of spatially and temporally separate V. cholerae populations obtained from infected naive or protected pups was tested. Recombination-based in vivo expression technology was used to assess virulence gene expression within these populations. Results. OMV immunization significantly reduced colonization of neonates challenged with HI V. cholerae. Vibrio cholerae that had colonized the naive host was HI, whereas V. cholerae excreted by neonates born to OMV-immunized dams, although viable, was hypoinfectious and failed to fully induce virulence gene expression. Conclusions. OMV immunization can significantly reduce the V. cholerae burden upon challenge with HI V. cholerae and can also block transmission from immune mice by reducing the infectivity of shed bacteria. PMID:22147790

  7. Immunization with Escherichia coli outer membrane vesicles protects bacteria-induced lethality via Th1 and Th17 cell responses.

    PubMed

    Kim, Oh Youn; Hong, Bok Sil; Park, Kyong-Su; Yoon, Yae Jin; Choi, Seng Jin; Lee, Won Hee; Roh, Tae-Young; Lötvall, Jan; Kim, Yoon-Keun; Gho, Yong Song

    2013-04-15

    Outer membrane vesicles (OMVs), secreted from Gram-negative bacteria, are spherical nanometer-sized proteolipids enriched with outer membrane proteins. OMVs, also known as extracellular vesicles, have gained interests for use as nonliving complex vaccines and have been examined for immune-stimulating effects. However, the detailed mechanism on how OMVs elicit the vaccination effect has not been studied extensively. In this study, we investigated the immunological mechanism governing the protective immune response of OMV vaccines. Immunization with Escherichia coli-derived OMVs prevented bacteria-induced lethality and OMV-induced systemic inflammatory response syndrome. As verified by adoptive transfer and gene-knockout studies, the protective effect of OMV immunization was found to be primarily by the stimulation of T cell immunity rather than B cell immunity, especially by the OMV-Ag-specific production of IFN-γ and IL-17 from T cells. By testing the bacteria-killing ability of macrophages, we also demonstrated that IFN-γ and IL-17 production is the main factor promoting bacterial clearances. Our findings reveal that E. coli-derived OMV immunization effectively protects bacteria-induced lethality and OMV-induced systemic inflammatory response syndrome primarily via Th1 and Th17 cell responses. This study therefore provides a new perspective on the immunological detail regarding OMV vaccination. PMID:23514742

  8. Yersinia pestis with regulated delayed attenuation as a vaccine candidate to induce protective immunity against plague.

    PubMed

    Sun, Wei; Roland, Kenneth L; Kuang, Xiaoying; Branger, Christine G; Curtiss, Roy

    2010-03-01

    Two mutant strains of Yersinia pestis KIM5+, a Deltacrp mutant and a mutant with arabinose-dependent regulated delayed-shutoff crp expression (araC P(BAD) crp), were constructed, characterized in vitro, and evaluated for virulence, immunogenicity, and protective efficacy in mice. Both strains were highly attenuated by the subcutaneous (s.c.) route. The 50% lethal doses (LD(50)s) of the Deltacrp and araC P(BAD) crp mutants were approximately 1,000,000-fold and 10,000-fold higher than those of Y. pestis KIM5+, respectively, indicating that both strains were highly attenuated. Mice vaccinated s.c. with 3.8 x 10(7) CFU of the Deltacrp mutant developed high anti-Y. pestis and anti-LcrV serum IgG titers, both with a strong Th2 bias, and induced protective immunity against subcutaneous challenge with virulent Y. pestis (80% survival) but no protection against pulmonary challenge. Mice vaccinated with 3.0 x 10(4) CFU of the araC P(BAD) crp mutant also developed high anti-Y. pestis and anti-LcrV serum IgG titers but with a more balanced Th1/Th2 response. This strain induced complete protection against s.c. challenge and partial protection (70% survival) against pulmonary challenge. Our results demonstrate that arabinose-dependent regulated crp expression is an effective strategy to attenuate Y. pestis while retaining strong immunogenicity, leading to protection against the pneumonic and bubonic forms of plague.

  9. Stimulation of Lung Innate Immunity Protects against Lethal Pneumococcal Pneumonia in Mice

    PubMed Central

    Clement, Cecilia G.; Evans, Scott E.; Evans, Christopher M.; Hawke, David; Kobayashi, Ryuji; Reynolds, Paul R.; Moghaddam, Seyed J.; Scott, Brenton L.; Melicoff, Ernestina; Adachi, Roberto; Dickey, Burton F.; Tuvim, Michael J.

    2008-01-01

    Rationale: The lungs are a common site of serious infection in both healthy and immunocompromised subjects, and the most likely route of delivery of a bioterror agent. Since the airway epithelium shows great structural plasticity in response to inflammatory stimuli, we hypothesized it might also show functional plasticity. Objectives: To test the inducibility of lung defenses against bacterial challenge. Methods: Mice were treated with an aerosolized lysate of ultraviolet-killed nontypeable (unencapsulated) Haemophilus influenzae (NTHi), then challenged with a lethal dose of live Streptococcus pneumoniae (Spn) delivered by aerosol. Measurements and Main Results: Treatment with the NTHi lysate induced complete protection against challenge with a lethal dose of Spn if treatment preceded challenge by 4 to 24 hours. Lesser levels of protection occurred at shorter (83% at 2 h) and longer (83% at 48–72 h) intervals between treatment and challenge. There was also some protection when treatment was given 2 hours after challenge (survival increased from 14 to 57%), but not 24 hours after challenge. Protection did not depend on recruited neutrophils or resident mast cells and alveolar macrophages. Protection was specific to the airway route of infection, correlated in magnitude and time with rapid bacterial killing within the lungs, and was associated with increases of multiple antimicrobial polypeptides in lung lining fluid. Conclusions: We infer that protection derives from stimulation of local innate immune mechanisms, and that activated lung epithelium is the most likely cellular effector of this response. Augmentation of innate antimicrobial defenses of the lungs might have therapeutic value. PMID:18388354

  10. Mucosal Immunization with Recombinant Fusion Protein DnaJ-ΔA146Ply Enhances Cross-Protective Immunity against Streptococcus pneumoniae Infection in Mice via Interleukin 17A

    PubMed Central

    Liu, Yusi; Wang, Hong; Zhang, Shuai; Zeng, Lingbin; Xu, Xiuyu; Wu, Kaifeng; Wang, Wei; Yin, Nanlin; Song, Zhixin

    2014-01-01

    Pneumolysin (Ply) and its variants are protective against pneumococcal infections in animal models, and as a Toll-like receptor 4 agonist, pneumolysin has been reported to be a mucosal adjuvant. DnaJ has been approved as a useful candidate vaccine protein; we therefore designed novel fusion proteins of DnaJ with a form of Ply that has a deletion of A146 (ΔA146Ply-DnaJ [the C terminus of ΔA146Ply connected with the N terminus of DnaJ] and DnaJ-ΔA146Ply [the C terminus of DnaJ connected with the N terminus of ΔA146Ply]) to test whether they are protective against focal and lethal pneumococcal infections and their potential protective mechanisms. The purified proteins were used to intranasally immunize the animals without additional adjuvant. Immunization with DnaJ-ΔA146Ply or DnaJ plus ΔA146Ply (Ply with a single deletion of A146) could significantly reduce S. pneumoniae colonization in the nasopharynx and lung relative with DnaJ alone. Additionally, we observed the best protection for DnaJ-ΔA146Ply-immunized mice after challenge with lethal doses of S. pneumoniae strains, which was comparable to that achieved by PPV23. Mice immunized with DnaJ-ΔA146Ply produced significantly higher levels of anti-DnaJ IgG in serum and secretory IgA (sIgA) in saliva than those immunized with DnaJ alone. The production of IL-17A was also striking in DnaJ-ΔA146Ply-immunized mice. IL-17A knockout (KO) mice did not benefit from DnaJ-ΔA146Ply immunization in colonization experiments, and sIgA production was impaired in IL-17A KO mice. Collectively, our results indicate a mucosal adjuvant potential for ΔA146Ply and that, without additional adjuvant, DnaJ-ΔA146Ply fusion protein exhibits extensive immune stimulation and is effective against pneumococcal challenges, properties which are partially attributed to the IL-17A-mediated immune responses. PMID:24491576

  11. Immunity to Avirulent Enterovirus 71 and Coxsackie A16 Virus Protects against Enterovirus 71 Infection in Mice▿

    PubMed Central

    Wu, Te-Chia; Wang, Ya-Fang; Lee, Yi-Ping; Wang, Jen-Ren; Liu, Ching-Chuan; Wang, Shih-Min; Lei, Huan-Yao; Su, Ih-Jen; Yu, Chun-Keung

    2007-01-01

    In this study, we sought to determine whether intratypic and intertypic cross-reactivity protected against enterovirus 71 (EV71) infection in a murine infection model. We demonstrate that active immunization of 1-day-old mice with avirulent EV71 strain or coxsackie A16 virus (CA16) by the oral route developed anti-EV71 antibodies with neutralizing activity (1:16 and 1:2, respectively). Splenocytes from both EV71- and CA16-immunized mice proliferated upon EV71 or CA16, but not coxsackie B3 virus (CB3), antigen stimulation. Immunized mice became more resistant to virulent EV71 strain challenge than nonimmunized mice. There was an increase in the percentage of activated splenic T cells and B cells in the immunized mice 2 days after EV71 challenge. The CA16 immune serum reacted with EV71 antigens in an enzyme-linked immunosorbent assay and neutralized EV71 but not CB3 or poliovirus at a titer of 1:4. Passive immunization with the CA16 immune serum reduced the clinical score, diminished the organ viral load, and increased the survival rate of mice upon EV71 challenge. CB3 neither shared in vitro cross-reactivity with EV71 nor provided in vivo protection after both active and passive immunization. These results illustrated that live vaccine is feasible for EV71 and that intertypic cross-reactivity of enteroviruses may provide a way to determine the prevalence of EV71. PMID:17626076

  12. Attitudes of Turkish midwives and nurses working at hospitals towards people living with human immunodeficiency virus/acquired immune deficiency syndrome.

    PubMed

    Akgun Kostak, Melahat; Unsar, Serap; Kurt, Seda; Erol, Ozgul

    2012-10-01

    Health professionals caring for people living with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) show poor or negative attitudes because of fear of contagion. Therefore, it is important to know the attitudes of midwives' and nurses' towards people living with HIV/AIDS. The aim of this descriptive and cross-sectional study is to assess the attitudes of Turkish midwives and nurses working at hospitals to people living with HIV/AIDS and to identify factors that affect these attitudes. A group of 46 midwives and 192 nurses working in hospitals were included in the study. Data were collected through AIDS Attitude Scale. Age, professional experience, number of children and marital status influenced the attitudes of the participants towards people living with HIV/AIDS. We concluded that higher level of education appear to positively influence the attitudes of the participants. Education programmes including evidence-based nursing implications might be planned to improve positive attitudes and to prevent stigmatization of people living with HIV/AIDS.

  13. The thymus in acquired immune deficiency syndrome. Comparison with other types of immunodeficiency diseases, and presence of components of human immunodeficiency virus type 1.

    PubMed Central

    Schuurman, H. J.; Krone, W. J.; Broekhuizen, R.; van Baarlen, J.; van Veen, P.; Golstein, A. L.; Huber, J.; Goudsmit, J.

    1989-01-01

    The authors studied thymus specimens taken at autopsy from eight acquired immune deficiency syndrome (AIDS) patients and compared these with those taken from four patients with congenital immunodeficiency (unrelated to an intrinsic thymus defect) and seven patients after allogeneic bone marrow transplantation. In all cases, histology showed a severely involuted architecture, compatible with a debilitating disease before death. There were no major differences between thymus tissue in AIDS patients and in the other patients studied. This argues against the claim expressed in the literature that the epithelial microenvironment incurs particular HIV-1-induced injury in AIDS. This conclusion is substantiated by immunohistochemistry for HIV-1 gag and env proteins, and by hybridohistochemistry for gag/pol and env mRNA of HIV-1. Positive cells were observed only in low numbers, both inside the epithelial parenchyma and in the (expanded) perivascular areas. An interesting finding was the labeling of subcapsular/medullary epithelium in normal uninvoluted thymus by a number of antibodies to HIV-1 gag p17 and p24 proteins. Compatible with this labeling was the staining of epithelial stalks in hyperinvoluted thymuses irrespective of disease category. The previously reported cross-reactivity between HIV-1 core protein and thymosin alpha 1 cannot fully explain this observation, because the epithelium in the hyperinvoluted state is negative for thymosin alpha 1. This study confirms and extends previous reports on the endogenous presence of epitopes of retroviral antigens in thymic epithelium. Images Figure 1 Figure 2 Figure 3 PMID:2474255

  14. Utility of /sup 67/Ga scintigraphy and bronchial washings in the diagnosis and treatment of Pneumocystis carinii pneumonia in patients with the acquired immune deficiency syndrome

    SciTech Connect

    Tuazon, C.U.; Delaney, M.D.; Simon, G.L.; Witorsch, P.; Varma, V.M.

    1985-11-01

    Twenty patients with the acquired immune deficiency syndrome (AIDS) and suspected Pneumocystis carinii pneumonia were evaluated by /sup 67/Ga scintigraphy and fiberoptic bronchoscopy for initial diagnosis and response to therapy. Lung uptake of /sup 67/Ga was demonstrated in 100% of AIDS patients with P. carinii pneumonia, including those with subclinical infection. Fiberoptic bronchoscopy identified P. carinii in the bronchial washings of 100% of cases (19 patients), whereas only 13 of 16 (81%) patients had P. carinii in lung tissue obtained by transbronchial biopsy. Repeat fiberoptic bronchoscopy was performed in 16 of 20 patients. After 2 to 4 wk of therapy, P. carinii was identified in bronchial washings in 8 of 16 (50%) patients and in transbronchial biopsy in 1 of 10 (10%) patients examined. Bronchial washing has a higher yield than transbronchial biopsy in demonstrating P. carinii in patients with AIDS and may evolve as the procedure of choice in such patients. Based on the clinical course and results of /sup 67/Ga scintigraphy and fiberoptic bronchoscopy in AIDS patients with P. carinii pneumonia, optimal therapy may require at least 3 wk of treatment.

  15. Acquired Immune Deficiency Syndrome (AIDS) and the Veterans' Administration. Hearing before the Subcommittee on Hospitals and Health Care of the Committee on Veterans' Affairs. House of Representatives, One Hundredth Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Committee on Veterans' Affairs.

    This document presents witness testimony and prepared statements from the Congressional hearing called to examine the issue of acquired immune deficiency syndrome (AIDS) and the role of the Veterans' Administration (VA) in combating AIDS. Opening statements are included from Representatives G. V. Montgomery, J. Roy Rowland, Joseph P. Kennedy, II,…

  16. Intranasal immunization with a replication-deficient adenoviral vector expressing the fusion glycoprotein of respiratory syncytial virus elicits protective immunity in BALB/c mice

    SciTech Connect

    Fu, Yuanhui; He, Jinsheng; Zheng, Xianxian; Wu, Qiang; Zhang, Mei; Wang, Xiaobo; Wang, Yan; Xie, Can; Tang, Qian; Wei, Wei; Wang, Min; Song, Jingdong; Qu, Jianguo; Zhang, Ying; Wang, Xin; Hong, Tao

    2009-04-17

    Human respiratory syncytial virus (RSV) is a serious pediatric pathogen of the lower respiratory tract worldwide. There is currently no clinically approved vaccine against RSV infection. Recently, it has been shown that a replication-deficient first generation adenoviral vector (FGAd), which encodes modified RSV attachment glycoprotein (G), elicits long-term protective immunity against RSV infection in mice. The major problem in developing such a vaccine is that G protein lacks MHC-I-restricted epitopes. However, RSV fusion glycoprotein (F) is a major cytotoxic T-lymphocyte epitope in humans and mice, therefore, an FGAd-encoding F (FGAd-F) was constructed and evaluated for its potential as an RSV vaccine in a murine model. Intranasal (i.n.) immunization with FGAd-F generated serum IgG, bronchoalveolar lavage secretory IgA, and RSV-specific CD8+ T-cell responses in BALB/c mice, with characteristic balanced or mixed Th1/Th2 CD4+ T-cell responses. Serum IgG was significantly elevated after boosting with i.n. FGAd-F. Upon challenge, i.n. immunization with FGAd-F displayed an effective protective role against RSV infection. These results demonstrate FGAd-F is able to induce effective protective immunity and is a promising vaccine regimen against RSV infection.

  17. Humoral Immunity to West Nile Virus Is Long-Lasting and Protective in the House Sparrow (Passer domesticus)

    PubMed Central

    Nemeth, Nicole M.; Oesterle, Paul T.; Bowen, Richard A.

    2009-01-01

    The house sparrow (Passer domesticus) is a common and abundant amplifying host of West Nile virus (WNV) and many survive infection and develop humoral immunity. We experimentally inoculated house sparrows with WNV and monitored duration and protection of resulting antibodies. Neutralizing antibody titers remained relatively constant for ≥ 36 months (N = 42) and provided sterilizing immunity for up to 36 months post-inoculation in 98.6% of individuals (N = 72). These results imply that immune house sparrows are protected from WNV infection for multiple transmission seasons. Additionally, individuals experiencing WNV-associated mortality reached significantly higher peak viremia titers than survivors, and mortality during acute infection was significantly higher in caged versus free-flight sparrows. A better understanding of the long-term immunity and mortality rates in birds is valuable in interpreting serosurveillance and diagnostic data and modeling transmission and disease dynamics. PMID:19407139

  18. Characterisation of the protective immune response following subcutaneous vaccination of susceptible mice against Trichuris muris.

    PubMed

    Dixon, Helen; Little, Matthew C; Else, Kathryn J

    2010-05-01

    Trichuris muris is a laboratory model for the human whipworm Trichuris trichiura which infects approximately 1 billion people in tropical and sub-tropical countries. The development of a vaccine would control trichuriasis by promoting the acquisition of immunity during childhood, thereby reducing faecal egg output by the community into their environment. Resistance to T. muris, defined as expulsion of the parasite prior to patency, requires the development of a T helper 2 (Th2) response during a primary infection. To our knowledge this is the first study to describe the protective immune response in the peripheral lymph nodes (PLN), mesenteric lymph nodes (MLN) and colonic mucosa following s.c. vaccination against T. muris. Susceptible AKR mice were either vaccinated with T. muris excretory-secretory product (ES) in incomplete Freund's adjuvant (IFA) (ES/IFA) or injected with PBS in IFA (PBS/IFA) and for protection experiments were infected with embryonated infective T. muris eggs 10 days later. The ES/IFA vaccine induced the proliferation of PLN cells and their production of Th2 cytokines and the Th1-associated cytokine IFN-gamma. Following a challenge infection, the ES/IFA vaccination offered susceptible mice complete protection. While MLN-derived IFN-gamma was produced by infected mice following either ES/IFA vaccination or PBS/IFA, the protection of susceptible mice by ES/IFA was characterised by the production of MLN-derived Th2 cytokines. Goblet cell hyperplasia and the influx and alternative activation of macrophages were observed locally in the gut post-challenge infection. The rate of epithelial turnover did not appear to be increased by vaccination, suggesting that there are differences in the mechanisms of expulsion between 'natural resistance' and 'vaccinated resistance'. High levels of serum IgG1 and cell-bound IgG1 in the colon of mice protected by the ES/IFA vaccine suggest that antibody may be involved in vaccination-induced worm expulsion. PMID

  19. Immunization of Mice with a Live Transconjugant Shigella Hybrid Strain Induced Th1 and Th17 Cell-Mediated Immune Responses and Confirmed Passive Protection Against Heterologous Shigellae.

    PubMed

    Nag, D; Koley, H; Sinha, R; Mukherjee, P; Sarkar, C; Withey, J H; Gachhui, R

    2016-02-01

    An avirulent, live transconjugant Shigella hybrid (LTSHΔstx) strain was constructed in our earlier study by introducing a plasmid vector, pPR1347, into a Shiga toxin gene deleted Shigella dysenteriae 1. Three successive oral administrations of LTSHΔstx to female adult mice produced comprehensive passive heterologous protection in their offspring against challenge with wild-type shigellae. Production of NO and different cytokines such asIL-12p70, IL-1β and IL-23 in peritoneal mice macrophages indicated that LTSHΔstx induced innate and adaptive immunity in mice. Furthermore, production of IFN-γ, IL-10 and IL-17 in LTSH-primed splenic CD4+ T cell suggested that LTSHΔstx may induce Th1 and Th17 cell-mediated immune responses. Exponential increase of the serum IgG and IgA titre against whole shigellae was observed in immunized adult mice during and after the immunization with the highest peak on day 35. Antigen-specific sIgA was also determined from intestinal lavage of immunized mice. The stomach extracts of neonates from immunized mice, mainly containing mother's milk, contained significant levels of anti-LTSHΔstx immunoglobulin. These studies suggest that the LTSHΔstx could be a new live oral vaccine candidate against shigellosis in the near future. PMID:26478541

  20. Protective Efficacy and Pulmonary Immune Response Following Subcutaneous and Intranasal BCG Administration in Mice.

    PubMed

    Uranga, Santiago; Marinova, Dessislava; Martin, Carlos; Aguilo, Nacho

    2016-01-01

    Despite global coverage of intradermal BCG vaccination, tuberculosis remains one of the most prevalent infectious diseases in the world. Preclinical data have encouraged pulmonary tuberculosis vaccines as a promising strategy to prevent pulmonary disease, which is responsible for transmission. In this work, we describe the methodology used to demonstrate in the mouse model the benefits of intranasal BCG vaccination when compared to subcutaneous. Our data revealed greater protective efficacy following intranasal BCG administration. In addition, our results indicate that pulmonary vaccination triggers a higher immune response in lungs, including Th1 and Th17 responses, as well as an increase of immunoglobulin A (IgA) concentration in respiratory airways. Our data show correlation between protective efficacy and the presence of IL17-producing cells in lungs post-Mycobacterium tuberculosis challenge, suggesting a role for this cytokine in the protective response conferred by pulmonary vaccination. Finally, we detail the global workflow we have developed to study respiratory vaccination in the mouse model, which could be extrapolated to other tuberculosis vaccines, apart from BCG, targeting the mucosal response or other pulmonary routes of administration such as the intratracheal or aerosol. PMID:27684521

  1. Association of the Host Immune Response with Protection Using a Live Attenuated African Swine Fever Virus Model

    PubMed Central

    Carlson, Jolene; O’Donnell, Vivian; Alfano, Marialexia; Velazquez Salinas, Lauro; Holinka, Lauren G.; Krug, Peter W.; Gladue, Douglas P.; Higgs, Stephen; Borca, Manuel V.

    2016-01-01

    African swine fever (ASF) is a lethal hemorrhagic disease of swine caused by a double-stranded DNA virus, ASF virus (ASFV). There is no vaccine to prevent the disease and current control measures are limited to culling and restricting animal movement. Swine infected with attenuated strains are protected against challenge with a homologous virulent virus, but there is limited knowledge of the host immune mechanisms generating that protection. Swine infected with Pretoriuskop/96/4 (Pret4) virus develop a fatal severe disease, while a derivative strain lacking virulence-associated gene 9GL (Pret4Δ9GL virus) is completely attenuated. Swine infected with Pret4Δ9GL virus and challenged with the virulent parental virus at 7, 10, 14, 21, and 28 days post infection (dpi) showed a progressive acquisition of protection (from 40% at 7 dpi to 80% at 21 and 28 dpi). This animal model was used to associate the presence of host immune response (ASFV-specific antibody and interferon (IFN)-γ responses, or specific cytokine profiles) and protection against challenge. With the exception of ASFV-specific antibodies in survivors challenged at 21 and 28 dpi, no association between the parameters assessed and protection could be established. These results, encompassing data from 65 immunized swine, underscore the complexity of the system under study, suggesting that protection relies on the concurrence of different host immune mechanisms. PMID:27782090

  2. Immunization.

    ERIC Educational Resources Information Center

    Guerin, Nicole; And Others

    1986-01-01

    Contents of this double journal issue concern immunization and primary health care of children. The issue decribes vaccine storage and sterilization techniques, giving particular emphasis to the role of the cold chain, i.e., the maintenance of a specific temperature range to assure potency of vaccines as they are moved from a national storage…

  3. Immunization of Mice with Recombinant Brucella abortus Organic Hydroperoxide Resistance (Ohr) Protein Protects Against a Virulent Brucella abortus 544 Infection.

    PubMed

    Hop, Huynh Tan; Reyes, Alisha Wehdnesday Bernardo; Simborio, Hannah Leah Tadeja; Arayan, Lauren Togonon; Min, Won Gi; Lee, Hu Jang; Lee, Jin Ju; Chang, Hong Hee; Kim, Suk

    2016-01-01

    In this study, the Brucella abortus ohr gene coding for an organic hydroperoxide resistance protein (Ohr) was cloned into a maltose fusion protein expression system (pMAL), inserted into Escherichia coli, and purified, and its immunogenicity was evaluated by western blot analysis using Brucella-positive mouse sera. The purified recombinant Ohr (rOhr) was treated with adjuvant and injected intraperitoneally into BALB/c mice. A protective immune response analysis revealed that rOhr induced a significant increase in both the IgG1 and IgG2a titers, and IgG2a reached a higher level than IgG1 after the second and third immunizations. Additionally, immunization with rOhr induced high production of IFN-γ as well as proinflammatory cytokines such as TNF, MCP-1, IL-12p70, and IL-6, but a lesser amount of IL-10, suggesting that rOhr predominantly elicited a cell-mediated immune response. In addition, immunization with rOhr caused a significantly higher degree of protection against a virulent B. abortus infection compared with a positive control group consisting of mice immunized with maltose-binding protein. These findings showed that B. abortus rOhr was able to induce both humoral and cell-mediated immunity in mice, which suggested that this recombinant protein could be a potential vaccine candidate for animal brucellosis.

  4. Photodynamic therapy can induce non-specific protective immunity against a bacterial infection

    NASA Astrophysics Data System (ADS)

    Tanaka, Masamitsu; Mroz, Pawel; Dai, Tianhong; Kinoshita, Manabu; Morimoto, Yuji; Hamblin, Michael R.

    2012-03-01

    Photodynamic therapy (PDT) for cancer is known to induce an immune response against the tumor, in addition to its well-known direct cell-killing and vascular destructive effects. PDT is becoming increasingly used as a therapy for localized infections. However there has not to date been a convincing report of an immune response being generated against a microbial pathogen after PDT in an animal model. We have studied PDT as a therapy for bacterial arthritis caused by Staphylococcus aureus infection in the mouse knee. We had previously found that PDT of an infection caused by injection of MRSA (5X107 CFU) into the mouse knee followed 3 days later by 1 μg of Photofrin and 635- nm diode laser illumination with a range of fluences within 5 minutes, gave a biphasic dose response. The greatest reduction of MRSA CFU was seen with a fluence of 20 J/cm2, whereas lower antibacterial efficacy was observed with fluences that were either lower or higher. We then tested the hypothesis that the host immune response mediated by neutrophils was responsible for most of the beneficial antibacterial effect. We used bioluminescence imaging of luciferase expressing bacteria to follow the progress of the infection in real time. We found similar results using intra-articular methylene blue and red light, and more importantly, that carrying out PDT of the noninfected joint and subsequently injecting bacteria after PDT led to a significant protection from infection. Taken together with substantial data from studies using blocking antibodies we believe that the pre-conditioning PDT regimen recruits and stimulates neutrophils into the infected joint which can then destroy bacteria that are subsequently injected and prevent infection.

  5. Costimulatory Effects of an Immunodominant Parasite Antigen Paradoxically Prevent Induction of Optimal CD8 T Cell Protective Immunity.

    PubMed

    Eickhoff, Christopher S; Zhang, Xiuli; Vasconcelos, Jose R; Motz, R Geoffrey; Sullivan, Nicole L; O'Shea, Kelly; Pozzi, Nicola; Gohara, David W; Blase, Jennifer R; Di Cera, Enrico; Hoft, Daniel F

    2016-09-01

    Trypanosoma cruzi infection is controlled but not eliminated by host immunity. The T. cruzi trans-sialidase (TS) gene superfamily encodes immunodominant protective antigens, but expression of altered peptide ligands by different TS genes has been hypothesized to promote immunoevasion. We molecularly defined TS epitopes to determine their importance for protection versus parasite persistence. Peptide-pulsed dendritic cell vaccination experiments demonstrated that one pair of immunodominant CD4+ and CD8+ TS peptides alone can induce protective immunity (100% survival post-lethal parasite challenge). TS DNA vaccines have been shown by us (and others) to protect BALB/c mice against T. cruzi challenge. We generated a new TS vaccine in which the immunodominant TS CD8+ epitope MHC anchoring positions were mutated, rendering the mutant TS vaccine incapable of inducing immunity to the immunodominant CD8 epitope. Immunization of mice with wild type (WT) and mutant TS vaccines demonstrated that vaccines encoding enzymatically active protein and the immunodominant CD8+ T cell epitope enhance subdominant pathogen-specific CD8+ T cell responses. More specifically, CD8+ T cells from WT TS DNA vaccinated mice were responsive to 14 predicted CD8+ TS epitopes, while T cells from mutant TS DNA vaccinated mice were responsive to just one of these 14 predicted TS epitopes. Molecular and structural biology studies revealed that this novel costimulatory mechanism involves CD45 signaling triggered by enzymatically active TS. This enhancing effect on subdominant T cells negatively regulates protective immunity. Using peptide-pulsed DC vaccination experiments, we have shown that vaccines inducing both immunodominant and subdominant epitope responses were significantly less protective than vaccines inducing only immunodominant-specific responses. These results have important implications for T. cruzi vaccine development. Of broader significance, we demonstrate that increasing breadth of T

  6. Costimulatory Effects of an Immunodominant Parasite Antigen Paradoxically Prevent Induction of Optimal CD8 T Cell Protective Immunity

    PubMed Central

    Vasconcelos, Jose R.; Motz, R. Geoffrey; Sullivan, Nicole L.; Gohara, David W.; Blase, Jennifer R.; Di Cera, Enrico; Hoft, Daniel F.

    2016-01-01

    Trypanosoma cruzi infection is controlled but not eliminated by host immunity. The T. cruzi trans-sialidase (TS) gene superfamily encodes immunodominant protective antigens, but expression of altered peptide ligands by different TS genes has been hypothesized to promote immunoevasion. We molecularly defined TS epitopes to determine their importance for protection versus parasite persistence. Peptide-pulsed dendritic cell vaccination experiments demonstrated that one pair of immunodominant CD4+ and CD8+ TS peptides alone can induce protective immunity (100% survival post-lethal parasite challenge). TS DNA vaccines have been shown by us (and others) to protect BALB/c mice against T. cruzi challenge. We generated a new TS vaccine in which the immunodominant TS CD8+ epitope MHC anchoring positions were mutated, rendering the mutant TS vaccine incapable of inducing immunity to the immunodominant CD8 epitope. Immunization of mice with wild type (WT) and mutant TS vaccines demonstrated that vaccines encoding enzymatically active protein and the immunodominant CD8+ T cell epitope enhance subdominant pathogen-specific CD8+ T cell responses. More specifically, CD8+ T cells from WT TS DNA vaccinated mice were responsive to 14 predicted CD8+ TS epitopes, while T cells from mutant TS DNA vaccinated mice were responsive to just one of these 14 predicted TS epitopes. Molecular and structural biology studies revealed that this novel costimulatory mechanism involves CD45 signaling triggered by enzymatically active TS. This enhancing effect on subdominant T cells negatively regulates protective immunity. Using peptide-pulsed DC vaccination experiments, we have shown that vaccines inducing both immunodominant and subdominant epitope responses were significantly less protective than vaccines inducing only immunodominant-specific responses. These results have important implications for T. cruzi vaccine development. Of broader significance, we demonstrate that increasing breadth of T

  7. Development of immunity to porcine rotavirus in piglets protected from disease by bovine colostrum.

    PubMed Central

    Bridger, J C; Brown, J F

    1981-01-01

    Bovine colostrum with rotavirus-neutralizing activity was fed for 10 days to two groups of piglets, one of which was inoculated intranasally with a rotavirus of porcine origin. A third group, which did not receive colostrum, was also inoculated with the virus, and these piglets developed diarrhea, excreted rotavirus in the feces, and died 6 days after infection. In contrast, the infected piglets fed with bovine colostrum remained healthy, although they developed antibody to rotavirus. Twenty-seven days after the primary inoculation, piglets in the colostrum-fed groups were inoculated intranasally with virus. Those in the previously unexposed group became clinically ill and excreted rotavirus, whereas those which had experienced a previous subclinical infection (the colostrum-fed, virus-inoculated group) remained healthy. It was concluded that bovine colostrum protected piglets from the clinical effects of a porcine rotavirus and that these animals developed an immunity which prevented subsequent disease. PMID:6262251

  8. Virus-like particles as antigenic nanomaterials for inducing protective immune responses in the lung

    PubMed Central

    Rynda-Apple, Agnieszka; Patterson, Dustin P; Douglas, Trevor

    2015-01-01

    The lung is a major entry point for many of the most detrimental pathogens to human health. The onslaught of pathogens encountered by the lung is counteracted by protective immune responses that are generated locally, which can be stimulated through vaccine strategies to prevent pathogen infections. Here, we discuss the use of virus-like particles (VLPs), nonpathogen derivatives of viruses or protein cage structures, to construct new vaccines exploiting the lung as a site for immunostimulation. VLPs are unique in their ability to be engineered with near molecular level detail and knowledge of their composition and structure. A summary of research in developing VLP-based vaccines for the lung is presented that suggests promising results for future vaccine development. PMID:25325241

  9. Interleukin-27-Producing CD4(+) T Cells Regulate Protective Immunity during Malaria Parasite Infection.

    PubMed

    Kimura, Daisuke; Miyakoda, Mana; Kimura, Kazumi; Honma, Kiri; Hara, Hiromitsu; Yoshida, Hiroki; Yui, Katsuyuki

    2016-03-15

    Interleukin-27 (IL-27) is a heterodimeric regulatory cytokine of the IL-12 family, which is produced by macrophages, dendritic cells, and B cells upon stimulation through innate immune receptors. Here, we described regulatory CD4(+) T cells that produce IL-27 in response to T cell receptor stimulation during malaria infection, inhibiting IL-2 production and clonal expansion of other T cells in an IL-27-dependent manner. IL-27-producing CD4(+) T cells were Foxp3(-)CD11a(+)CD49d(+) malaria antigen-specific CD4(+) T cells and were distinct from interferon-γ (IFN-γ) producing Th1 or IL-10 producing Tr1 cells. In mice lacking IL-27 in T cells, IL-2 production was restored and clonal expansion and IFN-γ production by specific CD4(+) T cells were improved, culminating in reduced parasite burden. This study highlights a unique population of IL-27 producing regulatory CD4(+) T cells and their critical role in the regulation of the protective immune response against malaria parasites.

  10. Prolongevity hormone FGF21 protects against immune senescence by delaying age-related thymic involution.

    PubMed

    Youm, Yun-Hee; Horvath, Tamas L; Mangelsdorf, David J; Kliewer, Steven A; Dixit, Vishwa Deep

    2016-01-26

    Age-related thymic degeneration is associated with loss of naïve T cells, restriction of peripheral T-cell diversity, and reduced healthspan due to lower immune competence. The mechanistic basis of age-related thymic demise is unclear, but prior evidence suggests that caloric restriction (CR) can slow thymic aging by maintaining thymic epithelial cell integrity and reducing the generation of intrathymic lipid. Here we show that the prolongevity ketogenic hormone fibroblast growth factor 21 (FGF21), a member of the endocrine FGF subfamily, is expressed in thymic stromal cells along with FGF receptors and its obligate coreceptor, βKlotho. We found that FGF21 expression in thymus declines with age and is induced by CR. Genetic gain of FGF21 function in mice protects against age-related thymic involution with an increase in earliest thymocyte progenitors and cortical thymic epithelial cells. Importantly, FGF21 overexpression reduced intrathymic lipid, increased perithymic brown adipose tissue, and elevated thymic T-cell export and naïve T-cell frequencies in old mice. Conversely, loss of FGF21 function in middle-aged mice accelerated thymic aging, increased lethality, and delayed T-cell reconstitution postirradiation and hematopoietic stem cell transplantation (HSCT). Collectively, FGF21 integrates metabolic and immune systems to prevent thymic injury and may aid in the reestablishment of a diverse T-cell repertoire in cancer patients following HSCT. PMID:26755598

  11. Amidase, a cell wall hydrolase, elicits protective immunity against Staphylococcus aureus and S. epidermidis.

    PubMed

    Nair, Nisha; Vinod, Vivek; Suresh, Maneesha K; Vijayrajratnam, Sukhithasri; Biswas, Lalitha; Peethambaran, Reshmi; Vasudevan, Anil Kumar; Biswas, Raja

    2015-01-01

    The morbidity and the mortality associated with Staphylococcus aureus and S. epidermidis infections have greatly increased due to the rapid emergence of highly virulent and antibiotic resistant strains. Development of a vaccine-based therapy is greatly desired. However, no staphylococcal vaccine is available till date. In this study, we have identified Major amidase (Atl-AM) as a prime candidate for future vaccine design against these pathogens. Atl-AM is a multi-functional non-covalently cell wall associated protein which is involved in staphylococcal cell separation after cell division, host extracellular matrix adhesion and biofilm formation. Atl-AM is present on the surface of diverse S. aureus and S. epidermidis strains. When used in combination with Freund's adjuvant, Atl-AM generated a mixed Th1 and Th2 mediated immune response which is skewed more toward Th1; and showed increased production of opsonophagocytic IgG2a and IgG2b antibodies. Significant protective immune response was observed when vaccinated mice were challenged with S. aureus or S. epidermidis. Vaccination prevented the systemic dissemination of both organisms. Our results demonstrate the remarkable efficacy of Atl-AM as a vaccine candidate against both of these pathogens.

  12. Isolation of Anti-Ricin Protective Antibodies Exhibiting High Affinity from Immunized Non-Human Primates

    PubMed Central

    Noy-Porat, Tal; Rosenfeld, Ronit; Ariel, Naomi; Epstein, Eyal; Alcalay, Ron; Zvi, Anat; Kronman, Chanoch; Ordentlich, Arie; Mazor, Ohad

    2016-01-01

    Ricin, derived from the castor bean plant Ricinus communis, is one of the most potent and lethal toxins known, against which there is no available antidote. To date, the use of neutralizing antibodies is the most promising post-exposure treatment for ricin intoxication. The aim of this study was to isolate high affinity anti-ricin antibodies that possess potent toxin-neutralization capabilities. Two non-human primates were immunized with either a ricin-holotoxin- or subunit-based vaccine, to ensure the elicitation of diverse high affinity antibodies. By using a comprehensive set of primers, immune scFv phage-displayed libraries were constructed and panned. A panel of 10 antibodies (five directed against the A subunit of ricin and five against the B subunit) was isolated and reformatted into a full-length chimeric IgG. All of these antibodies were found to neutralize ricin in vitro, and several conferred full protection to ricin-intoxicated mice when given six hours after exposure. Six antibodies were found to possess exceptionally high affinity toward the toxin, with KD values below pM (koff < 1 × 10−7 s−1) that were well correlated with their ability to neutralize ricin. These antibodies, alone or in combination, could be used for the development of a highly-effective therapeutic preparation for post-exposure treatment of ricin intoxication. PMID:26950154

  13. Amidase, a cell wall hydrolase, elicits protective immunity against Staphylococcus aureus and S. epidermidis.

    PubMed

    Nair, Nisha; Vinod, Vivek; Suresh, Maneesha K; Vijayrajratnam, Sukhithasri; Biswas, Lalitha; Peethambaran, Reshmi; Vasudevan, Anil Kumar; Biswas, Raja

    2015-01-01

    The morbidity and the mortality associated with Staphylococcus aureus and S. epidermidis infections have greatly increased due to the rapid emergence of highly virulent and antibiotic resistant strains. Development of a vaccine-based therapy is greatly desired. However, no staphylococcal vaccine is available till date. In this study, we have identified Major amidase (Atl-AM) as a prime candidate for future vaccine design against these pathogens. Atl-AM is a multi-functional non-covalently cell wall associated protein which is involved in staphylococcal cell separation after cell division, host extracellular matrix adhesion and biofilm formation. Atl-AM is present on the surface of diverse S. aureus and S. epidermidis strains. When used in combination with Freund's adjuvant, Atl-AM generated a mixed Th1 and Th2 mediated immune response which is skewed more toward Th1; and showed increased production of opsonophagocytic IgG2a and IgG2b antibodies. Significant protective immune response was observed when vaccinated mice were challenged with S. aureus or S. epidermidis. Vaccination prevented the systemic dissemination of both organisms. Our results demonstrate the remarkable efficacy of Atl-AM as a vaccine candidate against both of these pathogens. PMID:25841371

  14. Lactobacillus priming of the respiratory tract: Heterologous immunity and protection against lethal pneumovirus infection.

    PubMed

    Garcia-Crespo, Katia E; Chan, Calvin C; Gabryszewski, Stanislaw J; Percopo, Caroline M; Rigaux, Peter; Dyer, Kimberly D; Domachowske, Joseph B; Rosenberg, Helene F

    2013-03-01

    We showed previously that wild-type mice primed via intranasal inoculation with live or heat-inactivated Lactobacillus species were fully (100%) protected against the lethal sequelae of infection with the virulent pathogen, pneumonia virus of mice (PVM), a response that is associated with diminished expression of proinflammatory cytokines and diminished virus recovery. We show here that 40% of the mice primed with live Lactobacillus survived when PVM challenge was delayed for 5months. This robust and sustained resistance to PVM infection resulting from prior interaction with an otherwise unrelated microbe is a profound example of heterologous immunity. We undertook the present study in order to understand the nature and unique features of this response. We found that intranasal inoculation with L. reuteri elicited rapid, transient neutrophil recruitment in association with proinflammatory mediators (CXCL1, CCL3, CCL2, CXCL10, TNF-alpha and IL-17A) but not Th1 cytokines. IFNγ does not contribute to survival promoted by Lactobacillus-priming. Live L. reuteri detected in lung tissue underwent rapid clearance, and was undetectable at 24h after inoculation. In contrast, L. reuteri peptidoglycan (PGN) and L. reuteri genomic DNA (gDNA) were detected at 24 and 48h after inoculation, respectively. In contrast to live bacteria, intranasal inoculation with isolated L. reuteri gDNA elicited no neutrophil recruitment, had minimal impact on virus recovery and virus-associated production of CCL3, and provided no protection against the negative sequelae of virus infection. Isolated PGN elicited neutrophil recruitment and proinflammatory cytokines but did not promote sustained survival in response to subsequent PVM infection. Overall, further evaluation of the responses leading to Lactobacillus-mediated heterologous immunity may provide insight into novel antiviral preventive modalities.

  15. A cell wall protein-based vaccine candidate induce protective immune response against Sporothrix schenckii infection.

    PubMed

    Portuondo, Deivys Leandro; Batista-Duharte, Alexander; Ferreira, Lucas Souza; Martínez, Damiana Téllez; Polesi, Marisa Campos; Duarte, Roberta Aparecida; de Paula E Silva, Ana Carolina Alves; Marcos, Caroline Maria; Almeida, Ana Marisa Fusco de; Carlos, Iracilda Zeppone

    2016-02-01

    Sporotrichosis is a subcutaneous mycosis caused by several closely related thermo-dimorphic fungi of the Sporothrix schenckii species complex, affecting humans and other mammals. In the last few years, new strategies have been proposed for controlling sporotrichosis owning to concerns about its growing incidence in humans, cats, and dogs in Brazil, as well as the toxicity and limited efficacy of conventional antifungal drugs. In this study, we assessed the immunogenicity and protective properties of two aluminum hydroxide (AH)-adsorbed S. schenckii cell wall protein (ssCWP)-based vaccine formulations in a mouse model of systemic S. schenckii infection. Fractioning by SDS-PAGE revealed nine protein bands, two of which were functionally characterized: a 44kDa peptide hydrolase and a 47kDa enolase, which was predicted to be an adhesin. Sera from immunized mice recognized the 47kDa enolase and another unidentified 71kDa protein, whereas serum from S. schenckii-infected mice recognized both these proteins plus another unidentified 9.4kDa protein. Furthermore, opsonization with the anti-ssCWP sera led to markedly increased phagocytosis and was able to strongly inhibit the fungus' adhesion to fibroblasts. Immunization with the higher-dose AH-adjuvanted formulation led to increased ex vivo release of IL-12, IFN-γ, IL-4, and IL-17, whereas only IL-12 and IFN-γ were induced by the higher-dose non-adjuvanted formulation. Lastly, passive transference of the higher-dose AH-adjuvanted formulation's anti-ssCWP serum was able to afford in vivo protection in a subsequent challenge with S. schenckii, becoming a viable vaccine candidate for further testing.

  16. Oral administration of a recombinant attenuated Yersinia pseudotuberculosis strain elicits protective immunity against plague.

    PubMed

    Sun, Wei; Sanapala, Shilpa; Rahav, Hannah; Curtiss, Roy

    2015-11-27

    A Yersinia pseudotuberculosis PB1+ (Yptb PB1+) mutant strain combined with chromosome insertion of the caf1R-caf1A-caf1M-caf1 operon and deletions of yopJ and yopK, χ10068 [pYV-ω2 (ΔyopJ315 ΔyopK108) ΔlacZ044::caf1R-caf1M-caf1A-caf1] was constructed. Results indicated that gene insertion and deletion did not affect the growth rate of χ10068 compared to wild-type Yptb cultured at 26 °C. In addition, the F1 antigen in χ10068 was synthesized and secreted on the surface of bacteria at 37 °C (mammalian body temperature), not at ambient culture temperature (26 °C). Immunization with χ10068 primed antibody responses and specific T-cell responses to F1 and YpL (Y. pestis whole cell lysate). Oral immunization with a single dose of χ10068 provided 70% protection against a subcutaneous (s.c.) challenge with ∼ 2.6 × 10(5) LD50 of Y. pestis KIM6+ (pCD1Ap) (KIM6+Ap) and 90% protection against an intranasal (i.n.) challenge with ∼ 500 LD50 of KIM6+Ap in mice. Our results suggest that χ10068 can be used as an effective precursor to make a safe vaccine to prevent plague in humans and to eliminate plague circulation among humans and animals.

  17. Vaccines displaying mycobacterial proteins on biopolyester beads stimulate cellular immunity and induce protection against tuberculosis.

    PubMed

    Parlane, Natalie A; Grage, Katrin; Mifune, Jun; Basaraba, Randall J; Wedlock, D Neil; Rehm, Bernd H A; Buddle, Bryce M

    2012-01-01

    New improved vaccines are needed for control of both bovine and human tuberculosis. Tuberculosis protein vaccines have advantages with regard to safety and ease of manufacture, but efficacy against tuberculosis has been difficult to achieve. Protective cellular immune responses can be preferentially induced when antigens are displayed on small particles. In this study, Escherichia coli and Lactococcus lactis were engineered to produce spherical polyhydroxybutyrate (PHB) inclusions which displayed a fusion protein of Mycobacterium tuberculosis, antigen 85A (Ag85A)-early secreted antigenic target 6-kDa protein (ESAT-6). L. lactis was chosen as a possible production host due its extensive use in the food industry and reduced risk of lipopolysaccharide contamination. Mice were vaccinated with PHB bead vaccines with or without displaying Ag85A-ESAT-6, recombinant Ag85A-ESAT-6, or M. bovis BCG. Separate groups of mice were used to measure immune responses and assess protection against an aerosol M. bovis challenge. Increased amounts of antigen-specific gamma interferon, interleukin-17A (IL-17A), IL-6, and tumor necrosis factor alpha were produced from splenocytes postvaccination, but no or minimal IL-4, IL-5, or IL-10 was produced, indicating Th1- and Th17-biased T cell responses. Decreased lung bacterial counts and less extensive foci of inflammation were observed in lungs of mice receiving BCG or PHB bead vaccines displaying Ag85A-ESAT-6 produced in either E. coli or L. lactis compared to those observed in the lungs of phosphate-buffered saline-treated control mice. No differences between those receiving wild-type PHB beads and those receiving recombinant Ag85A-ESAT-6 were observed. This versatile particulate vaccine delivery system incorporates a relatively simple production process using safe bacteria, and the results show that it is an effective delivery system for a tuberculosis protein vaccine. PMID:22072720

  18. Passive immunization with antiserum to a nontoxic alpha-toxin mutant from Staphylococcus aureus is protective in a murine model.

    PubMed Central

    Menzies, B E; Kernodle, D S

    1996-01-01

    A nonhemolytic, nonlethal variant of Staphylococcus aureus alpha-toxin constructed via oligonucleotide-directed mutagenesis and containing a single amino acid substitution (H-35 to L) was used to immunize a rabbit. The resulting antiserum was cross-reactive with wild-type alpha-toxin and neutralized its hemolytic activity in vitro. Passive immunization of mice with rabbit antiserum conferred protection against lethal challenge with wild-type alpha-toxin and against acute lethal challenge with a high-alpha-toxin -producing S. aureus strain. H35L alpha-toxin may be useful as a protective immunogen in S. aureus vaccine studies. PMID:8613399

  19. Advax Delta Inulin Adjuvant Overcomes Immune Immaturity In Neonatal Mice Thereby Allowing Single–Dose Influenza Vaccine Protection

    PubMed Central

    Honda-Okubo, Yoshikazu; Ong, Chun Hao; Petrovsky, Nikolai

    2015-01-01

    Neonates are at high risk for influenza morbidity and mortality due to immune immaturity and lack of priming by prior exposure. Inactivated influenza vaccines are ineffective in infants under six months and to provide protection in older children generally require two doses given a month apart. This leaves few options for rapid protection of infants, e.g. during an influenza pandemic. We investigated whether Advax™, a novel polysaccharide adjuvant based on delta inulin microparticles could help overcome neonatal immune hypo-responsiveness and also whether it was possible to obtain single-dose influenza vaccine protection of babies against lethal infection. Inactivated influenza A/H1N1 vaccine (iH1N1) combined with Advax™ adjuvant administered as a single immunization to 7-day-old mouse pups significantly enhanced serum influenza-specific IgM, IgG1, IgG2a and IgG2b levels in association with a 3–4 fold increase in the frequency of splenic influenza-specific IgM and IgG antibody secreting cells versus pups immunized with iH1N1 alone. Pups immunized with Advax-adjuvanted iH1N1 had significantly higher influenza-stimulated splenocyte production of IFN-γ, IL-2, IL-4, and IL-10 and a 3–10 fold higher frequency of T cells IFN-γ secreting IL-2, IL-4 or IL-17 by ELISPOT. Immunisation with iH1N1+Advax adjuvant induced robust protection against influenza virus challenge 3 weeks post-immunization, whereas pups immunized with iH1N1 alone had no protection. Protection by Advax-adjuvanted iH1N1 was mediated by serum antibody and memory B cells rather than memory T cells as protection was lost in neonatal µMT mice that are B-cell deficient. Hence, Advax adjuvant overcame neonatal immune hypo-responsiveness and enabled single-dose protection of pups against otherwise lethal influenza infection, thereby supporting development of Advax™ as a neonatal vaccine adjuvant. PMID:26232344

  20. Intravaginal and intranasal immunizations are equally effective in inducing vaginal antibodies and conferring protection against vaginal candidiasis.

    PubMed

    De Bernardis, Flavia; Boccanera, Maria; Adriani, Daniela; Girolamo, Antonietta; Cassone, Antonio

    2002-05-01

    Oophorectomized, estrogen-treated rats were immunized by the intravaginal or intranasal route with a mannoprotein extract (MP) or secreted aspartyl proteinases (Sap) of Candida albicans, with or without cholera toxin as a mucosal adjuvant. Both routes of immunization were equally effective in (i) inducing anti-MP and anti-Sap vaginal antibodies and (ii) conferring a high degree of protection against the vaginal infection by the fungus. These data suggest that appropriate fungal antigens and adjuvant can be used to protect against candidal vaginitis, by either route.

  1. Influence of the home environment on the prevention of mother to child transmission of human immunodeficiency virus/acquired immune-deficiency syndrome in South Africa.

    PubMed

    Sewnunan, A; Modiba, L M

    2015-01-01

    The human immunodeficiency virus and acquired immune-deficiency syndrome (HIV/AIDS) is still a 'family crises' which marks the beginning of the deterioration of the family unit and the trauma in the emotional, psychological and material lives of both the mother and child. In South African context where the majority of HIV-positive mothers are young single women who live in extended families, disclosure to the sexual partner alone is not an adequate condition for the success of prevention of mother to child transmission (PMTCT). In South Africa, close to one in three women who attend antenatal clinics are HIV positive. KwaZulu-Natal is one of the worst affected provinces, where as many as 40-60% of pregnant women attending antenatal services are living with HIV infection. The study sought to investigate the link between the home environment and its contribution to the success of the programme on PMTCT of HIV/AIDS. A qualitative, explorative, descriptive and contextual study was used in this study to explore whether the home environment for the support system is available for the HIV-positive women on the PMTCT programme. The population of this study included all women who have undergone counselling and tested HIV positive and who have joined the programme on PMTCT of HIV/AIDS in a specific hospital in KwaZulu-Natal Province. Although 14 women agreed to participate in the study, only 10 women were interviewed as saturation was attained. Data were collected using semi-structured interview schedule. Interviews were audio-taped and field notes were taken. Content analysis was used and it was done manually. This study revealed that one of the major issues still surrounding HIV/AIDS and PMTCT is that of non-disclosure, selective disclosure and the stigma and discrimination that surrounds this disease. PMID:26694631

  2. Influence of the home environment on the prevention of mother to child transmission of human immunodeficiency virus/acquired immune-deficiency syndrome in South Africa.

    PubMed

    Sewnunan, A; Modiba, L M

    2015-01-01

    The human immunodeficiency virus and acquired immune-deficiency syndrome (HIV/AIDS) is still a 'family crises' which marks the beginning of the deterioration of the family unit and the trauma in the emotional, psychological and material lives of both the mother and child. In South African context where the majority of HIV-positive mothers are young single women who live in extended families, disclosure to the sexual partner alone is not an adequate condition for the success of prevention of mother to child transmission (PMTCT). In South Africa, close to one in three women who attend antenatal clinics are HIV positive. KwaZulu-Natal is one of the worst affected provinces, where as many as 40-60% of pregnant women attending antenatal services are living with HIV infection. The study sought to investigate the link between the home environment and its contribution to the success of the programme on PMTCT of HIV/AIDS. A qualitative, explorative, descriptive and contextual study was used in this study to explore whether the home environment for the support system is available for the HIV-positive women on the PMTCT programme. The population of this study included all women who have undergone counselling and tested HIV positive and who have joined the programme on PMTCT of HIV/AIDS in a specific hospital in KwaZulu-Natal Province. Although 14 women agreed to participate in the study, only 10 women were interviewed as saturation was attained. Data were collected using semi-structured interview schedule. Interviews were audio-taped and field notes were taken. Content analysis was used and it was done manually. This study revealed that one of the major issues still surrounding HIV/AIDS and PMTCT is that of non-disclosure, selective disclosure and the stigma and discrimination that surrounds this disease.

  3. Do-Not-Resuscitate Orders and/or Hospice Care, Psychological Health, and Quality of Life among Children/Adolescents with Acquired Immune Deficiency Syndrome

    PubMed Central

    Lyon, Maureen E.; Williams, Paige L.; Woods, Elizabeth R.; Hutton, Nancy; Butler, Anne M.; Sibinga, Erica; Brady, Michael T.; Oleske, James M.

    2009-01-01

    Objective The frequency of do-not-resuscitate (DNR) orders and hospice enrollment in children/adolescents living with acquired immune deficiency syndrome (AIDS) and followed in Pediatric AIDS Clinical Trials Group (PACTG) Study 219C was examined, and evaluated for any association with racial disparities or enhanced quality of life (QOL), particularly psychological adjustment. Methods A cross-sectional analysis of children with AIDS enrolled in this prospective multicenter observational study between 2000 and 2005 was conducted to evaluate the incidence of DNR/hospice overall and by calendar time. Linear regression models were used to compare caregivers' reported QOL scores within 6 domains between those with and without DNR/hospice care, adjusting for confounders. Results Seven hundred twenty-six (726) children with AIDS had a mean age of 12.9 years (standard deviation [SD] = 4.5), 51% were male, 60% black, 25% Hispanic. Twenty-one (2.9%) had either a DNR order (n = 16), hospice enrollment (n = 7), or both (n = 2). Of 41 children who died, 80% had no DNR/hospice care. Increased odds of DNR/hospice were observed for those with CD4% less than 15%, no current antiretroviral use, and prior hospitalization. No differences by race were detected. Adjusted mean QOL scores were significantly lower for those with DNR/hospice enrollment than those without across all domains except for psychological status and health care utilization. Poorer psychological status correlated with higher symptom distress, but not with DNR/hospice enrollment after adjusting for symptoms. Conclusions Children who died of AIDS rarely had DNR/hospice enrollment. National guidelines recommend that quality palliative care be integrated routinely with HIV care. Further research is needed to explore the barriers to palliative care and advance care planning in this population. PMID:18363489

  4. TolC plays a crucial role in immune protection conferred by Edwardsiella tarda whole-cell vaccines

    PubMed Central

    Wang, Chao; Peng, Bo; Li, Hui; Peng, Xuan-xian

    2016-01-01

    Although vaccines developed from live organisms have better efficacy than those developed from dead organisms, the mechanisms underlying this differential efficacy remain unexplored. In this study, we combined sub-immunoproteomics with immune challenge to investigate the action of the outer membrane proteome in the immune protection conferred by four Edwardsiella tarda whole-cell vaccines prepared via different treatments and to identify protective immunogens that play a key role in this immune protection. Thirteen spots representing five outer membrane proteins and one cytoplasmic protein were identified, and it was found that their abundance was altered in relation with the immune protective abilities of the four vaccines. Among these proteins, TolC and OmpA were found to be the key immunogens conferring the first and second highest degrees of protection, respectively. TolC was detected in the two effective vaccines (live and inactivated-30-F). The total antiserum and anti-OmpA titers were higher for the two effective vaccines than for the two ineffective vaccines (inactivated-80-F and inactivated-100). Further evidence demonstrated that the live and inactivated-30-F vaccines demonstrated stronger abilities to induce CD8+ and CD4+ T cell differentiation than the other two evaluated vaccines. Our results indicate that the outer membrane proteome changes dramatically following different treatments, which contributes to the effectiveness of whole-cell vaccines. PMID:27406266

  5. Major Basic Protein from Eosinophils and Myeloperoxidase from Neutrophils Are Required for Protective Immunity to Strongyloides stercoralis in Mice ▿

    PubMed Central

    O'Connell, Amy E.; Hess, Jessica A.; Santiago, Gilberto A.; Nolan, Thomas J.; Lok, James B.; Lee, James J.; Abraham, David

    2011-01-01

    Eosinophils and neutrophils contribute to larval killing during the primary immune response, and neutrophils are effector cells in the secondary response to Strongyloides stercoralis in mice. The objective of this study was to determine the molecular mechanisms used by eosinophils and neutrophils to control infections with S. stercoralis. Using mice deficient in the eosinophil granule products major basic protein (MBP) and eosinophil peroxidase (EPO), it was determined that eosinophils kill the larvae through an MBP-dependent mechanism in the primary immune response if other effector cells are absent. Infecting PHIL mice, which are eosinophil deficient, with S. stercoralis resulted in development of primary and secondary immune responses that were similar to those of wild-type mice, suggesting that eosinophils are not an absolute requirement for larval killing or development of secondary immunity. Treating PHIL mice with a neutrophil-depleting antibody resulted in a significant impairment in larval killing. Naïve and immunized mice with neutrophils deficient in myeloperoxidase (MPO) infected with S. stercoralis had significantly decreased larval killing. It was concluded that there is redundancy in the primary immune response, with eosinophils killing the larvae through an MBP-dependent mechanism and neutrophils killing the worms through an MPO-dependent mechanism. Eosinophils are not required for the development or function of secondary immunity, but MPO from neutrophils is required for protective secondary immunity. PMID:21482685

  6. A single immunization with a recombinant canine adenovirus type 2 expressing the seoul virus Gn glycoprotein confers protective immunity against seoul virus in mice.

    PubMed

    Yuan, Zi-Guo; Li, Xiu-Ming; Mahmmod, Yasser Saad; Wang, Xiao-Hu; Xu, Hui-Juan; Zhang, Xiu-Xiang

    2009-08-20

    Seoul virus (SEOV), a member of hantavirus genus, is one of the causative agents of hemorrhagic fever with renal syndrome (HFRS) and afflicts tens of thousands of people annually. In this paper, we evaluate the immune response induced by a replication-competent recombinant canine adenovirus type 2 expressing the Gn protein of SEOV (rCAV-2-Gn) in BALB/c mice. Sera from immunized mice contained neutralizing antibodies that could specifically recognize SEOV and neutralize its infectivity in vitro. Moreover, the recombinant virus induced complete protection against a lethal challenge with the highly virulent SEOV strain CC-2. Protective level neutralizing antibodies were maintained for at least 20 weeks. The efficacy of the recombinant was similar to that induced by a currently available inactivated HFRS vaccine. This recombinant virus is therefore a potential alternative to the inactivated vaccine.

  7. Mutual Interference between Cytomegalovirus and Reconstitution of Protective Immunity after Hematopoietic Cell Transplantation

    PubMed Central

    Reddehase, Matthias J.

    2016-01-01

    Hematopoietic cell transplantation (HCT) is a therapy option for aggressive forms of hematopoietic malignancies that are resistant to standard antitumoral therapies. Hematoablative treatment preceding HCT, however, opens a “window of opportunity” for latent Cytomegalovirus (CMV) by releasing it from immune control with the consequence of reactivation of productive viral gene expression and recurrence of infectious virus. A “window of opportunity” for the virus represents a “window of risk” for the patient. In the interim between HCT and reconstitution of antiviral immunity, primarily mediated by CD8+ T cells, initially low amounts of reactivated virus can expand exponentially, disseminate to essentially all organs, and cause multiple organ CMV disease, with interstitial pneumonia (CMV-IP) representing the most severe clinical manifestation. Here, I will review predictions originally made in the mouse model of experimental HCT and murine CMV infection, some of which have already paved the way to translational preclinical research and promising clinical trials of a preemptive cytoimmunotherapy of human CMV disease. Specifically, the mouse model has been pivotal in providing “proof of concept” for preventing CMV disease after HCT by adoptive transfer of preselected, virus epitope-specific effector and memory CD8+ T cells bridging the critical interim. However, CMV is not a “passive antigen” but is a pathogen that actively interferes with the reconstitution of protective immunity by infecting bone marrow (BM) stromal cells that otherwise form niches for hematopoiesis by providing the structural microenvironment and by producing hematopoietically active cytokines, the hemopoietins. Depending on the precise conditions of HCT, reduced homing of transplanted hematopoietic stem- and progenitor cells to infected BM stroma and impaired colony growth and lineage differentiation can lead to “graft failure.” In consequence, uncontrolled virus spread

  8. Protective immunity against respiratory tract challenge with Yersinia pestis in mice immunized with an adenovirus-based vaccine vector expressing V antigen.

    PubMed

    Chiuchiolo, Maria J; Boyer, Julie L; Krause, Anja; Senina, Svetlana; Hackett, Neil R; Crystal, Ronald G

    2006-11-01

    The aerosol form of the bacterium Yersinia pestis causes the pneumonic plague, a rapidly fatal disease. At present, no plague vaccines are available for use in the United States. One candidate for the development of a subunit vaccine is the Y. pestis virulence (V) antigen, a protein that mediates the function of the Yersinia outer protein virulence factors and suppresses inflammatory responses in the host. On the basis of the knowledge that adenovirus (Ad) gene-transfer vectors act as adjuvants in eliciting host immunity against the transgene they carry, we tested the hypothesis that a single administration of a replication-defective Ad gene-transfer vector encoding the Y. pestis V antigen (AdsecV) could stimulate strong protective immune responses without a requirement for repeat administration. AdsecV elicited specific T cell responses and high IgG titers in serum within 2 weeks after a single intramuscular immunization. Importantly, the mice were protected from a lethal intranasal challenge of Y. pestis CO92 from 4 weeks up to 6 months after immunization with a single intramuscular dose of AdsecV. These observations suggest that an Ad gene-transfer vector expressing V antigen is a candidate for development of an effective anti-plague vaccine.

  9. A single immunization with a recombinant canine adenovirus expressing the rabies virus G protein confers protective immunity against rabies in mice

    SciTech Connect

    Li Jianwei; Faber, Milosz; Papaneri, Amy; Faber, Marie-Luise; McGettigan, James P.; Schnell, Matthias J.; Dietzschold, Bernhard . E-mail: bernhard.dietzschold@jefferson.edu

    2006-12-20

    Rabies vaccines based on live attenuated rabies viruses or recombinant pox viruses expressing the rabies virus (RV) glycoprotein (G) hold the greatest promise of safety and efficacy, particularly for oral immunization of wildlife. However, while these vaccines induce protective immunity in foxes, they are less effective in other animals, and safety concerns have been raised for some of these vaccines. Because canine adenovirus 2 (CAV2) is licensed for use as a live vaccine for dogs and has an excellent efficacy and safety record, we used this virus as an expression vector for the RVG. The recombinant CAV2-RV G produces virus titers similar to those produced by wild-type CAV2, indicating that the RVG gene does not affect virus replication. Comparison of RVG expressed by CAV2-RV G with that of vaccinia-RV G recombinant virus (V-RG) revealed similar amounts of RV G on the cell surface. A single intramuscular or intranasal immunization of mice with CAV2-RVG induced protective immunity in a dose-dependent manner, with no clinical signs or discomfort from the virus infection regardless of the route of administration or the amount of virus.

  10. Oral immunization of mice with gamma-irradiated Brucella neotomae induces protection against intraperitoneal and intranasal challenge with virulent B. abortus 2308.

    PubMed

    Dabral, Neha; Martha-Moreno-Lafont; Sriranganathan, Nammalwar; Vemulapalli, Ramesh

    2014-01-01

    Brucella spp. are Gram-negative, facultative intracellular coccobacilli that cause one of the most frequently encountered zoonosis worldwide. Humans naturally acquire infection through consumption of contaminated dairy and meat products and through direct exposure to aborted animal tissues and fluids. No vaccine against brucellosis is available for use in humans. In this study, we tested the ability of orally inoculated gamma-irradiated B. neotomae and B. abortus RB51 in a prime-boost immunization approach to induce antigen-specific humoral and cell mediated immunity and protection against challenge with virulent B. abortus 2308. Heterologous prime-boost vaccination with B. abortus RB51 and B. neotomae and homologous prime-boost vaccination of mice with B. neotomae led to the production of serum and mucosal antibodies specific to the smooth LPS. The elicited serum antibodies included the isotypes of IgM, IgG1, IgG2a, IgG2b and IgG3. All oral vaccination regimens induced antigen-specific CD4(+) and CD8(+) T cells capable of secreting IFN-γ and TNF-α. Upon intra-peritoneal challenge, mice vaccinated with B. neotomae showed the highest level of resistance against virulent B. abortus 2308 colonization in spleen and liver. Experiments with different doses of B. neotomae showed that all tested doses of 10(9), 10(10) and 10(11) CFU-equivalent conferred significant protection against the intra-peritoneal challenge. However, a dose of 10(11) CFU-equivalent of B. neotomae was required for affording protection against intranasal challenge as shown by the reduced bacterial colonization in spleens and lungs. Taken together, these results demonstrate the feasibility of using gamma-irradiated B. neotomae as an effective and safe oral vaccine to induce protection against respiratory and systemic infections with virulent Brucella.

  11. Oral Immunization of Mice with Gamma-Irradiated Brucella neotomae Induces Protection against Intraperitoneal and Intranasal Challenge with Virulent B. abortus 2308

    PubMed Central

    Dabral, Neha; Martha-Moreno-Lafont; Sriranganathan, Nammalwar; Vemulapalli, Ramesh

    2014-01-01

    Brucella spp. are Gram-negative, facultative intracellular coccobacilli that cause one of the most frequently encountered zoonosis worldwide. Humans naturally acquire infection through consumption of contaminated dairy and meat products and through direct exposure to aborted animal tissues and fluids. No vaccine against brucellosis is available for use in humans. In this study, we tested the ability of orally inoculated gamma-irradiated B. neotomae and B. abortus RB51 in a prime-boost immunization approach to induce antigen-specific humoral and cell mediated immunity and protection against challenge with virulent B. abortus 2308. Heterologous prime-boost vaccination with B. abortus RB51 and B. neotomae and homologous prime-boost vaccination of mice with B. neotomae led to the production of serum and mucosal antibodies specific to the smooth LPS. The elicited serum antibodies included the isotypes of IgM, IgG1, IgG2a, IgG2b and IgG3. All oral vaccination regimens induced antigen-specific CD4+ and CD8+ T cells capable of secreting IFN-γ and TNF-α. Upon intra-peritoneal challenge, mice vaccinated with B. neotomae showed the highest level of resistance against virulent B. abortus 2308 colonization in spleen and liver. Experiments with different doses of B. neotomae showed that all tested doses of 109, 1010 and 1011 CFU-equivalent conferred significant protection against the intra-peritoneal challenge. However, a dose of 1011 CFU-equivalent of B. neotomae was required for affording protection against intranasal challenge as shown by the reduced bacterial colonization in spleens and lungs. Taken together, these results demonstrate the feasibility of using gamma-irradiated B. neotomae as an effective and safe oral vaccine to induce protection against respiratory and systemic infections with virulent Brucella. PMID:25225910

  12. Vaccination route that induces transforming growth factor beta production fails to elicit protective immunity against Leishmania donovani infection.

    PubMed

    Bhowmick, Sudipta; Mazumdar, Tuhina; Ali, Nahid

    2009-04-01

    BALB/c mice immunized intraperitoneally (i.p.) and intravenously (i.v.) with Leishmania donovani promastigote membrane antigens (LAg), either free or encapsulated in liposomes, were protected against challenge infection with L. donovani, whereas mice immunized by the subcutaneous (s.c.) and intramuscular routes were not protected. Protected mice showed strong parasite resistance in both the liver and spleen, along with enhanced immunoglobulin G2a and delayed-type hypersensitivity responses. Again, mice vaccinated through the i.p. and i.v. routes showed high levels of NO production after challenge infection. s.c. vaccination resulted in an increased capacity of the spleen cells to produce prechallenge transforming growth factor beta (TGF-beta) levels during the in vitro antigen recall response, whereas i.p. immunization induced production of prechallenge gamma interferon, interleukin-12 (IL-12), and IL-4 levels, with a Th1 bias. Exposure to antigen-stimulated splenocyte supernatants of i.p. but not s.c. immunized mice activated macrophages for in vitro parasite killing. As an enhanced level of TGF-beta was detected in supernatants from unprotected s.c. immunized mice, neutralization by anti-TGF-beta antibody enhanced in vitro macrophage killing activity. The suppressive role of this cytokine was evaluated in vivo by vaccination with liposomal LAg and anti-TGF-beta antibody. Upon parasite challenge, these animals showed significant protection in both the liver and spleen. Moreover, the addition of recombinant TGF-beta in splenocyte supernatants of i.p. immunized mice in vitro as well as in vivo inhibited the protective ability of the macrophages by the i.p. route. Thus, the induction of high prechallenge TGF-beta limits the efficacy of vaccination by routes that are nonprotective.

  13. Vaccinia virus MUC1 immunization of mice: immune response and protection against the growth of murine tumors bearing the MUC1 antigen.

    PubMed

    Acres, R B; Hareuveni, M; Balloul, J M; Kieny, M P

    1993-08-01

    MUC1 is a mucin found on the apical surfaces of some normal mammalian mucin-secreting cells. It is characterized by heavy glycosylation and a 20-amino-acid tandem repeat segment. In most cases of human breast adenocarcinoma, this antigen is overexpressed. Moreover, abnormal glycosylation exposes a novel peptide epitope within the tandem repeat, such that antibodies to this epitope can distinguish normal from malignant adenocarcinomatous breast tissue. We have constructed a vaccinia virus (VV) that carries the cDNA for the MUC1 antigen. Murine and human cells infected with this virus express the MUC1 molecule, with three to four tandem repeats per molecule and with the tumor-associated epitopes exposed. Mice immunized with this virus produce antibodies that recognize MUC1 outside the tandem repeat, within the tandem repeat, and within the tumor-associated protein core epitope. Tumorigenic P815 (DBA) and 3T3 (BALB/c) cells have been transfected with MUC1. Thirty percent of DBA mice immunized with VV-MUC1 are protected from growth of P815-MUC1 tumors when implanted with 10(5) cells. Immunized BALB/c mice show a late development of transfected 3T3 tumor cells. Immunized mice show a moderate MUC1-specific IgG titer, but it cannot be correlated with subsequent tumor rejection. No evidence for a MUC1-specific cytotoxic T lymphocyte response has been found after immunization with VV-MUC1. PMID:8280702

  14. Bordetella pertussis infection: pathogenesis, diagnosis, management, and the role of protective immunity.

    PubMed

    Kerr, J R; Matthews, R C

    2000-02-01

    Whooping cough is presently one of the ten most common causes of death from infectious disease worldwide. Despite a high vaccine uptake, resurgences of this disease have been observed in several countries. Virulence factors of Bordetella pertussis include agglutinogens, fimbriae, P.69/pertactin, pertussis toxin, filamentous haemagglutinin, adenylate cyclase, tracheal cytotoxin, dermonecrotic toxin, lipopolysaccharide, tracheal colonisation factor, serum resistance factor, and type III secretion. Virulence factor expression is regulated by the bvgAS locus, a two-component signal transduction system. The pathophysiologic sequence consists of attachment (fimbriae, P.69/pertactin, tracheal colonisation factor, pertussis toxin, filamentous haemagglutinin), evasion of host defence (adenylate cyclase, pertussis toxin, serum resistance factor), local effects (tracheal cytotoxin), and systemic effects (pertussis toxin). Bordetella pertussis is transmitted by respiratory droplets and causes disease only in humans. Various diagnostic methods are available, including culture, serological methods, and the polymerase chain reaction. Serotyping of isolates to detect agglutinogens 2 and 3 is useful because serotype 1,2 may be associated with higher mortality, and antibodies to these antigens (agglutinins) may be protective in both animals and humans. Immunisation using whole-cell vaccine is effective but is reactogenic. Acellular vaccines containing one to five components are being used increasingly in various countries. Protective immunity to pertussis correlates with high levels of antibody to each of pertactin, fimbriae, and pertussis toxin; however, doubt remains as to the relationship between agglutinogen 3 and fimbria 3, making results of trials investigating these virulence factors difficult to interpret. PMID:10746492

  15. Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete

    NASA Astrophysics Data System (ADS)

    Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

    2015-12-01

    A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl-]/[OH-] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels.

  16. Ginseng protects against respiratory syncytial virus by modulating multiple immune cells and inhibiting viral replication.

    PubMed

    Lee, Jong Seok; Lee, Yu-Na; Lee, Young-Tae; Hwang, Hye Suk; Kim, Ki-Hye; Ko, Eun-Ju; Kim, Min-Chul; Kang, Sang-Moo

    2015-01-01

    Ginseng has been used in humans for thousands of years but its effects on viral infection have not been well understood. We investigated the effects of red ginseng extract (RGE) on respiratory syncytial virus (RSV) infection using in vitro cell culture and in vivo mouse models. RGE partially protected human epithelial (HEp2) cells from RSV-induced cell death and viral replication. In addition, RGE significantly inhibited the production of RSV-induced pro-inflammatory cytokine (TNF-α) in murine dendritic and macrophage-like cells. More importantly, RGE intranasal pre-treatment prevented loss of mouse body weight after RSV infection. RGE treatment improved lung viral clearance and enhanced the production of interferon (IFN-γ) in bronchoalveolar lavage cells upon RSV infection of mice. Analysis of cellular phenotypes in bronchoalveolar lavage fluids showed that RGE treatment increased the populations of CD8+ T cells and CD11c+ dendritic cells upon RSV infection of mice. Taken together, these results provide evidence that ginseng has protective effects against RSV infection through multiple mechanisms, which include improving cell survival, partial inhibition of viral replication and modulation of cytokine production and types of immune cells migrating into the lung. PMID:25658239

  17. Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete

    PubMed Central

    Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

    2015-01-01

    A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl−]/[OH−] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels. PMID:26673425

  18. Immune response and protection elicited by DNA immunisation against Taenia cysticercosis.

    PubMed

    Wang, Qing-min; Sun, Shu-han; Hu, Zhen-lin; Wu, Dan; Wang, Zhong-chuan

    2003-04-01

    The study evaluated DNA vaccination in Taenia solium cysticercosis prevention by using cDNA of an antigen (cC1) from T. solium metacestode. pcDNA3-cC1 DNA vaccine was constructed by inserting the cDNA into the eukaryotic expression plasmid pcDNA3. Positive expression of the pcDNA3-cC1 product was confirmed by its transfection into COS7 cell and enzyme-linked immunoabsorbent assay using serum of pigs infected with T. solium metacestode. Immunisation of BALB/c mice with three injections of pcDNA3-cC1 induced antigen-specific immune responses of the Th1 phenotype. Inoculation of new-born pigs induced protection against challenge with T. solium by 73.3% reduction of the metacestode number. Antibodies elicited by DNA immunisation with pcDNA3-cC1 specifically reacted with native cC1 protein, which was mainly restricted to the cyst wall of T. solium metacestode. Positive apoptosis signals were also detected in the cyst wall cells of metacestode slices from pigs immunised with pcDNA3-cC1 by TUNEL staining method. Those suggested that apoptosis played a role in protecting pigs immunised with pcDNA3-cC1 nucleic acid vaccine from pathogen challenge.

  19. Self-immunity microcapsules for corrosion protection of steel bar in reinforced concrete.

    PubMed

    Wang, Yanshuai; Fang, Guohao; Ding, Weijian; Han, Ningxu; Xing, Feng; Dong, Biqin

    2015-12-17

    A novel microcapsule-based self-immunity system for reinforced concrete is proposed. Its feasibility for hindering the corrosion of steel rebar by means of lifting the threshold value of [Cl(-)]/[OH(-)] is discussed. Precisely controlled release behavior enables corrosion protection in the case of depassivation. The release process is characterized over a designated range of pH values, and its release characteristics of the microcapsules, triggered by decreasing pH value, are captured by observing that the core crystals are released when exposed to a signal (stimulus). The aim of corrosion protection of steel bar is achieved through the constantly-stabilized passive film, and its stability is promoted using continuous calcium hydroxide released from the microcapsule, restoring alkaline conditions. The test results exhibited that the release process of the microcapsules is a function of time. Moreover, the release rate of core materials could interact with environmental pH value, in which the release rate is found to increase remarkably with decreasing pH value, but is inhibited by high pH levels.

  20. Combination of Two Candidate Subunit Vaccine Antigens Elicits Protective Immunity to Ricin and Anthrax Toxin in Mice

    PubMed Central

    Vance, David J.; Rong, Yinghui; Brey, Robert N.; Mantis, Nicholas J.

    2014-01-01

    In an effort to develop combination vaccines for biodefense, we evaluated a ricin subunit antigen, RiVax, given in conjunction with an anthrax protective antigen, DNI. The combination led to high endpoint titer antibody response, neutralizing antibodies, and protective immunity against ricin and anthrax lethal toxin. This is a natural combination vaccine, since both antigens are recombinant subunit proteins that would be given to the same target population. PMID:25475957

  1. Combination of two candidate subunit vaccine antigens elicits protective immunity to ricin and anthrax toxin in mice.

    PubMed

    Vance, David J; Rong, Yinghui; Brey, Robert N; Mantis, Nicholas J

    2015-01-01

    In an effort to develop combination vaccines for biodefense, we evaluated a ricin subunit antigen, RiVax, given in conjunction with an anthrax protective antigen, DNI. The combination led to high endpoint titer antibody response, neutralizing antibodies, and protective immunity against ricin and anthrax lethal toxin. This is a natural combination vaccine, since both antigens are recombinant subunit proteins that would be given to the same target population.

  2. Advax delta inulin adjuvant overcomes immune immaturity in neonatal mice thereby allowing single-dose influenza vaccine protection.

    PubMed

    Honda-Okubo, Yoshikazu; Ong, Chun Hao; Petrovsky, Nikolai

    2015-09-11

    Neonates are at high risk for influenza morbidity and mortality due to immune immaturity and lack of priming by prior influenza virus exposure. Inactivated influenza vaccines are ineffective in infants under six months and to provide protection in older children generally require two doses given a month apart. This leaves few options for rapid protection of infants, e.g. during an influenza pandemic. We investigated whether Advax™, a novel polysaccharide adjuvant based on delta inulin microparticles could help overcome neonatal immune hypo-responsiveness. We first tested whether it was possible to use Advax to obtain single-dose vaccine protection of neonatal pups against lethal influenza infection. Inactivated influenza A/H1N1 vaccine (iH1N1) combined with Advax™ adjuvant administered as a single subcutaneous immunization to 7-day-old mouse pups significantly enhanced serum influenza-specific IgM, IgG1, IgG2a and IgG2b levels and was associated with a 3-4 fold increase in the frequency of splenic influenza-specific IgM and IgG antibody secreting cells. Pups immunized with Advax had significantly higher splenocyte influenza-stimulated IFN-γ, IL-2, IL-4, and IL-10 production by CBA and a 3-10 fold higher frequency of IFN-γ, IL-2, IL-4 or IL-17 secreting T cells by ELISPOT. Immunization with iH1N1+Advax induced robust protection of pups against virus challenge 3 weeks later, whereas pups immunized with iH1N1 antigen alone had no protection. Protection by Advax-adjuvanted iH1N1 was dependent on memory B cells rather than memory T cells, with no protection in neonatal μMT mice that are B-cell deficient. Hence, Advax adjuvant overcame neonatal immune hypo-responsiveness and enabled single-dose protection of pups against otherwise lethal influenza infection, thereby supporting ongoing development of Advax™ as a neonatal vaccine adjuvant.

  3. Protection of rats against Mycoplasma arthritidis-induced arthritis by active and passive immunizations with two surface antigens.

    PubMed Central

    Washburn, L R; Weaver, E J

    1997-01-01

    We previously identified two surface-exposed Mycoplasma arthritidis protein antigens, designated MAA1 and MAA2, that may be involved in cytadherence. Since adherence to host tissues is an important first step in most bacterial infections, we suggest that MAA1 and MAA2 may be virulence factors for M. arthritidis. In order to provide evidence for such a role, we conducted a series of experiments in which rats were actively immunized with each of these proteins purified from sodium dodecyl sulfate-polyacrylamide gels or passively immunized with poly- or monoclonal antibodies against MAA1 and MAA2. In each case, immunity against MAA1 and MAA2 conferred at least partial protection against M. arthritidis-induced disease. The greatest protection was achieved by passive immunization with monoclonal antibody A9a, directed against a surface-exposed epitope of putative adhesin MAA1. Because protective immunity in most bacterial infections is directed against major virulence factors, these results suggest that MAA1 and MAA2 may play a role in the pathogenesis of M. arthritidis-induced arthritis of rats, possibly by mediating initial colonization of joint tissues. PMID:9144371

  4. Characterization and protective potential of the immune response to Taenia solium paramyosin in a murine model of cysticercosis.

    PubMed

    Vázquez-Talavera, J; Solís, C F; Terrazas, L I; Laclette, J P

    2001-09-01

    Paramyosin has been proposed as a vaccine candidate in schistosomiasis and filariasis. However, limited information is available about its protective potential against cysticercosis and the immune response it induces. Immunization of mice with recombinant full-length paramyosin of Taenia solium (TPmy) results in about a 52% reduction in parasite burden after a subsequent challenge by intraperitoneal inoculation of Taenia crassiceps cysticerci. Immunization assays using recombinant fragments of TPmy, corresponding approximately to thirds on the amino, central, or carboxyl regions, suggest that protective epitopes are located mostly in the amino-end third. Proliferation assays using T cells obtained from mice immunized with the full-length recombinant TPmy also showed a preferential response to the amino-terminal fragment. In contrast, antibodies in the sera from these mice predominantly recognize epitopes located in the carboxyl-terminal fragment, being the immunoglobulin G1 subclass, the predominant antibody isotype. Characterization of the cellular immune response induced against the protective amino-terminal fragment reveals production of gamma interferon and interleukin-2, but not interleukin-4, suggesting a Th1-like profile.

  5. The Evolutionarily Conserved Mediator Subunit MDT-15/MED15 Links Protective Innate Immune Responses and Xenobiotic Detoxification

    PubMed Central

    McEwan, Deborah L.; Conery, Annie L.; Ausubel, Frederick M.

    2014-01-01

    Metazoans protect themselves from environmental toxins and virulent pathogens through detoxification and immune responses. We previously identified a small molecule xenobiotic toxin that extends survival of Caenorhabditis elegans infected with human bacterial pathogens by activating the conserved p38 MAP kinase PMK-1 host defense pathway. Here we investigate the cellular mechanisms that couple activation of a detoxification response to innate immunity. From an RNAi screen of 1,420 genes expressed in the C. elegans intestine, we identified the conserved Mediator subunit MDT-15/MED15 and 28 other gene inactivations that abrogate the induction of PMK-1-dependent immune effectors by this small molecule. We demonstrate that MDT-15/MED15 is required for the xenobiotic-induced expression of p38 MAP kinase PMK-1-dependent immune genes and protection from Pseudomonas aeruginosa infection. We also show that MDT-15 controls the induction of detoxification genes and functions to protect the host from bacteria-derived phenazine toxins. These data define a central role for MDT-15/MED15 in the coordination of xenobiotic detoxification and innate immune responses. PMID:24875643

  6. Characterization and Protective Potential of the Immune Response to Taenia solium Paramyosin in a Murine Model of Cysticercosis

    PubMed Central

    Vázquez-Talavera, José; Solís, Carlos F.; Terrazas, Luis I.; Laclette, Juan P.

    2001-01-01

    Paramyosin has been proposed as a vaccine candidate in schistosomiasis and filariasis. However, limited information is available about its protective potential against cysticercosis and the immune response it induces. Immunization of mice with recombinant full-length paramyosin of Taenia solium (TPmy) results in about a 52% reduction in parasite burden after a subsequent challenge by intraperitoneal inoculation of Taenia crassiceps cysticerci. Immunization assays using recombinant fragments of TPmy, corresponding approximately to thirds on the amino, central, or carboxyl regions, suggest that protective epitopes are located mostly in the amino-end third. Proliferation assays using T cells obtained from mice immunized with the full-length recombinant TPmy also showed a preferential response to the amino-terminal fragment. In contrast, antibodies in the sera from these mice predominantly recognize epitopes located in the carboxyl-terminal fragment, being the immunoglobulin G1 subclass, the predominant antibody isotype. Characterization of the cellular immune response induced against the protective amino-terminal fragment reveals production of gamma interferon and interleukin-2, but not interleukin-4, suggesting a Th1-like profile. PMID:11500411

  7. Protection of rats against Mycoplasma arthritidis-induced arthritis by active and passive immunizations with two surface antigens.

    PubMed

    Washburn, L R; Weaver, E J

    1997-05-01

    We previously identified two surface-exposed Mycoplasma arthritidis protein antigens, designated MAA1 and MAA2, that may be involved in cytadherence. Since adherence to host tissues is an important first step in most bacterial infections, we suggest that MAA1 and MAA2 may be virulence factors for M. arthritidis. In order to provide evidence for such a role, we conducted a series of experiments in which rats were actively immunized with each of these proteins purified from sodium dodecyl sulfate-polyacrylamide gels or passively immunized with poly- or monoclonal antibodies against MAA1 and MAA2. In each case, immunity against MAA1 and MAA2 conferred at least partial protection against M. arthritidis-induced disease. The greatest protection was achieved by passive immunization with monoclonal antibody A9a, directed against a surface-exposed epitope of putative adhesin MAA1. Because protective immunity in most bacterial infections is directed against major virulence factors, these results suggest that MAA1 and MAA2 may play a role in the pathogenesis of M. arthritidis-induced arthritis of rats, possibly by mediating initial colonization of joint tissues.

  8. The role of sex hormones and the tissue environment in immune protection against HIV in the female reproductive tract.

    PubMed

    Wira, Charles R; Rodriguez-Garcia, Marta; Shen, Zheng; Patel, Mickey; Fahey, John V

    2014-08-01

    Despite extensive studies of the mucosal immune system in the female reproductive tract (FRT) and its regulation by sex hormones, relatively little attention has been paid to the tissue environment in the FRT that regulates immune cell function. Consisting of secretions from epithelial cells (EC), stromal fibroblasts, and immune cells in tissues from the upper (Fallopian tubes, uterus, and endocervix) and lower (ectocervix and vagina) tracts, each tissue compartment is unique and precisely regulates immune cells to optimize conditions for successful pregnancy and protection against sexually transmitted diseases including HIV. Our goal in this review is to focus on the mucosal (tissue) environment in the upper and lower FRT. Specifically, this review will identify the contributions of EC and fibroblasts to the tissue environment and examine the impact of this environment on HIV-target cells. Much remains to be learned about the complex interactions with the tissue environment at different sites in the FRT and the ways in which they are regulated by sex hormones and chemical contraceptives. Awareness of the involvement of the tissue environment in determining immune cell function and HIV acquisition is crucial for understanding the mechanisms that lead to HIV prevention, acquisition, and the development of new therapeutic modalities of immune protection.

  9. Protective immune response of live attenuated thermo-adapted peste des petits ruminants vaccine in goats.

    PubMed

    Balamurugan, V; Sen, A; Venkatesan, G; Bhanuprakash, V; Singh, R K

    2014-01-01

    Virulent isolate of peste des petits ruminants virus (PPRV) of Indian origin (PPRV Jhansi 2003) initially adapted in Vero cells was further propagated in thermo-adapted (Ta) Vero cells grown at 40 °C for attaining thermo-adaption and attenuation of virus for development of Ta vaccine against PPR in goats and sheep. The virus was attenuated up to 50 passages in Ta Vero cells, at which, the virus was found sterile, innocuous in mice and guinea pigs and safe in seronegative goats and sheep. The developed vaccine was tested for its immunogenicity in goats and sheep by subcutaneous inoculation of 100 TCID50 (0.1 field dose), 10(3) TCID50 (one field dose) and 10(5) TCID50 (100 field doses) of the attenuated virus along with controls as per OIE described protocols for PPR vaccine testing and were assessed for PPRV-specific antibodies 7-28 days post vaccination (dpv) by PPR competitive ELISA and serum neutralization tests. The PPRV antibodies were detected in all immunized goats and sheep and goats were protective when challenged with virulent PPRV at 28th dpv along with controls for potency testing of the vaccine. The attenuated vaccine did not induce any adverse reaction at high dose (10(5) TCID50) in goats and sheep and provided complete protection even at low dose (10(2) TCID50) in goats when challenged with virulent virus. There was no shedding and horizontal transmission of the attenuated virus to in-contact controls. The results indicate that the developed PPR Ta attenuated virus is innocuous, safe, immunogenic and potent or efficacious vaccine candidate alternative to the existing vaccines for the protection of goats and sheep against PPR in the tropical countries like India. PMID:25674603

  10. Single Immunization With a Monovalent Vesicular Stomatitis Virus–Based Vaccine Protects Nonhuman Primates Against Heterologous Challenge With Bundibugyo ebolavirus

    PubMed Central

    Falzarano, Darryl; Feldmann, Friederike; Grolla, Allen; Leung, Anders; Ebihara, Hideki; Strong, James E.; Marzi, Andrea; Takada, Ayato; Jones, Shane; Gren, Jason; Geisbert, Joan; Jones, Steven M.; Geisbert, Thomas W.

    2011-01-01

    The recombinant vesicular stomatitis virus (rVSV) vector-based monovalent vaccine platform expressing a filovirus glycoprotein has been demonstrated to provide protection from lethal challenge with Ebola (EBOV) and Marburg (MARV) viruses both prophylactically and after exposure. This platform provides protection between heterologous strains within a species; however, protection from lethal challenge between species has been largely unsuccessful. To determine whether the rVSV-EBOV vaccines have the potential to provide protection against a newly emerging, phylogenetically related species, cynomolgus macaques were vaccinated with an rVSV vaccine expressing either the glycoprotein of Zaire ebolavirus (ZEBOV) or Côte d’Ivoire ebolavirus (CIEBOV) and then challenged with Bundibugyo ebolavirus (BEBOV), which was recently proposed as a new EBOV species following an outbreak in Uganda in 2007. A single vaccination with the ZEBOV–specific vaccine provided cross-protection (75% survival) against subsequent BEBOV challenge, whereas vaccination with the CIEBOV–specific vaccine resulted in an outcome similar to mock-immunized animals (33% and 25% survival, respectively). This demonstrates that monovalent rVSV-based vaccines may be useful against a newly emerging species; however, heterologous protection across species remains challenging and may depend on enhancing the immune responses either through booster immunizations or through the inclusion of multiple immunogens. PMID:21987745

  11. Disruption of Early Tumor Necrosis Factor Alpha Signaling Prevents Classical Activation of Dendritic Cells in Lung-Associated Lymph Nodes and Development of Protective Immunity against Cryptococcal Infection

    PubMed Central

    Xu, Jintao; Eastman, Alison J.; Flaczyk, Adam; Neal, Lori M.; Zhao, Guolei; Carolan, Jacob; Malachowski, Antoni N.; Stolberg, Valerie R.; Yosri, Mohammed; Chensue, Stephen W.; Curtis, Jeffrey L.; Osterholzer, John J.

    2016-01-01

    ABSTRACT Anti-tumor necrosis factor alpha (anti-TNF-α) therapies have been increasingly used to treat inflammatory diseases and are associated with increased risk of invasive fungal infections, including Cryptococcus neoformans infection. Using a mouse model of cryptococcal infection, we investigated the mechanism by which disruption of early TNF-α signaling results in the development of nonprotective immunity against C. neoformans. We found that transient depletion of TNF-α inhibited pulmonary fungal clearance and enhanced extrapulmonary dissemination of C. neoformans during the adaptive phase of the immune response. Higher fungal burdens in TNF-α-depleted mice were accompanied by markedly impaired Th1 and Th17 responses in the infected lungs. Furthermore, early TNF-α depletion also resulted in disrupted transcriptional initiation of the Th17 polarization program and subsequent upregulation of Th1 genes in CD4+ T cells in the lung-associated lymph nodes (LALN) of C. neoformans-infected mice. These defects in LALN T cell responses were preceded by a dramatic shift from a classical toward an alternative activation of dendritic cells (DC) in the LALN of TNF-α-depleted mice. Taken together, our results indicate that early TNF-α signaling is required for optimal DC activation, and the initial Th17 response followed by Th1 transcriptional prepolarization of T cells in the LALN, which further drives the development of protective immunity against cryptococcal infection in the lungs. Thus, administration of anti-TNF-α may introduce a particularly greater risk for newly acquired fungal infections that require generation of protective Th1/Th17 responses for their containment and clearance. PMID:27406560

  12. Immunization of DNA vaccine encoding C3d-VP1 fusion enhanced protective immune response against foot-and-mouth disease virus.

    PubMed

    Fan, Huiying; Tong, Tiezhu; Chen, Huanchun; Guo, Aizhen

    2007-10-01

    Because foot-and-mouth disease virus (FMDV) remains a great problem to many livestock of agricultural importance, safe, effective vaccines are in great need. DNA vaccine would be a promising candidate but the design remains to be optimized. VP1 gene of FMDV strain O/ES/2001 was linked to three copies of either porcine or murine C3d or four copies of a 28-aa fragment of murine C3d containing the CR2 receptor binding domain (M28). The resultant plasmids encoding C3d/M28-VP1 fusion or only VP1 as control were immunized guinea pigs. Both cellular and humoral immune responses were evaluated and protection was observed after virus challenge. As a result, although the plasmid encoding only VP1 could elicit virus-binding antibody detected by ELISA, splenocyte proliferation, IL-4 and IFN-gamma production, the levels were significantly less than C3d/M28-VP1 fusion. Furthermore, VP1 failed to induce neutralization antibody and protect animals against virus challenge, while murine C3d-VP1 fusion efficiently induced neutralization antibody response and provided 87.50% of the animals with complete protection and 12.50% with partial protection. Among murine C3d, M28, and porcine C3d, the adjuvant effect of murine C3d is strongest, followed by porcine C3d, and last murine M28. In conclusion, the fact that C3d genes, when coupled to VP1 gene, are able to greatly enhance the protective immune response of VP1 DNA in guinea pigs suggests that C3d-VP1 DNA chimera has a significant potential for use as a novel DNA vaccine against FMDV. PMID:17497212

  13. Protection of non-immunized broiler chicks housed with immunized cohorts against infection with Eimeria maxima and E. acervulina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of live oocyst vaccines is becoming increasingly important in the control of avian coccidosis in broiler chicks. Knowledge of the mechanisms of how chicks uptake oocysts and become immune is important for optimizing delivery of live vaccines. The current study tests the hypothesis that chick...

  14. Tetraspanin-3 regulates protective immunity against Eimera tenella infection following immunization with dendritic cell-derived exosomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of immunization with dendritic cell (DC) exosomes, which had been incubated or non-incubated with an anti-tetraspanin-3 (Tspan-3) blocking antibody (Ab), were studied using an experimental model of Eimeria tenella avian coccidiosis. Purified exosomes from cecal tonsil and splenic DCs exp...

  15. Genetically Engineered Ascorbic acid-deficient Live Mutants of Leishmania donovani induce long lasting Protective Immunity against Visceral Leishmaniasis.

    PubMed

    Anand, Sneha; Madhubala, Rentala

    2015-06-02

    Visceral leishmaniasis caused by Leishmania donovani is the most severe systemic form of the disease. There are still no vaccines available for humans and there are limitations associated with the current therapeutic regimens for leishmaniasis. Recently, we reported functional importance of Arabino-1, 4-lactone oxidase (ALO) enzyme from L. donovani involved in ascorbate biosynthesis pathway. In this study, we have shown that ΔALO parasites do not affect the ability of null mutants to invade visceral organs but severely impair parasite persistence beyond 16 week in BALB/c mice and hence are safe as an immunogen. Both short term (5 week) and long term (20 week) immunization with ΔALO parasites conferred sustained protection against virulent challenge in BALB/c mice, activated splenocytes and resulted in induction of pro-inflammatory cytokine response. Protection in immunized mice after challenge correlated with the stimulation of IFN-γ producing CD4(+) and CD8(+) T cells. Antigen-mediated cell immunity correlated with robust nitrite and superoxide generation, macrophage-derived oxidants critical in controlling Leishmania infection. Our data shows that live attenuated ΔALO parasites are safe, induce protective immunity and can provide sustained protection against Leishmania donovani. We further conclude that the parasites attenuated in their anti-oxidative defence mechanism can be exploited as vaccine candidates.

  16. Myeloid-derived suppressor cells help protective immunity to Leishmania major infection despite suppressed T cell responses.

    PubMed

    Pereira, Wânia F; Ribeiro-Gomes, Flávia L; Guillermo, Landi V Costilla; Vellozo, Natália S; Montalvão, Fabrício; Dosreis, George A; Lopes, Marcela F

    2011-12-01

    Th1/Th2 cytokines play a key role in immune responses to Leishmania major by controlling macrophage activation for NO production and parasite killing. MDSCs, including myeloid precursors and immature monocytes, produce NO and suppress T cell responses in tumor immunity. We hypothesized that NO-producing MDSCs could help immunity to L. major infection. Gr1(hi)(Ly6C(hi)) CD11b(hi) MDSCs elicited by L. major infection suppressed polyclonal and antigen-specific T cell proliferation. Moreover, L. major-induced MDSCs killed intracellular parasites in a NO-dependent manner and reduced parasite burden in vivo. By contrast, treatment with ATRA, which induces MDSCs to differentiate into macrophages, increased development of lesions, parasite load, and T cell proliferation in draining LNs. Altogether, these results indicate that NO-producing MDSCs help protective immunity to L. major infection, despite suppressed T cell proliferation.

  17. Assessment of protection from systemic infection or disease afforded by low to intermediate titers of passively acquired neutralizing antibody against bovine viral diarrhea virus in calves.

    PubMed

    Bolin, S R; Ridpath, J F

    1995-06-01

    Colostrum-deprived calves (n = 24) were fed various amounts of colostrum, colostrum substitute, or milk replacer to establish a range in titer of passively acquired viral neutralizing antibody in serum. The calves were then challenge exposed intranasally with a virulent, noncytopathic bovine viral diarrhea virus (BVDV-890). After viral challenge exposure, calves were monitored for fever, leukopenia, thrombocytopenia, and diarrhea. In addition, viral isolation and viral titration were performed on specimens of nasal secretions, buffy coat cells, and serum obtained from the calves. Fever and systemic spread of virus were detected in calves that had viral neutralizing titer of 256 or lower. Calves that had viral neutralizing titer lower than 16 developed severe clinical disease manifested by fever, leukopenia, thrombocytopenia, and diarrhea. Severity and duration of signs of disease decreased as titers of passively acquired viral neutralizing antibody increased. These results indicate that low to intermediate titers of passively acquired viral neutralizing antibody were not sufficient to fully protect calves from virulent bovine viral diarrhea virus.

  18. Coadministration of protoxin Cry1Ac from Bacillus thuringiensis with metacestode extract confers protective immunity to murine cysticercosis.

    PubMed

    Ibarra-Moreno, S; García-Hernández, A L; Moreno-Fierros, L

    2014-06-01

    The Bacillus thuringiensis Cry1Ac protoxin (pCry1Ac) is a promising mucosal immunogen and adjuvant that induces protective immunity against Naegleria fowleri and malaria infection models. We determined whether pCry1Ac acted as a protective adjuvant against infection with Taenia crassiceps. BALB/C mice were thrice i.p. immunized with (i) pCry1Ac, (ii) metacestode extract, (iii) extract + pCry1Ac or (iv) vehicle, challenged with metacestodes on day 26 and then sacrificed 35 days later. Cysticerci in the peritoneal cavity were counted, while the serum antibody response and cytokines were analysed after immunization and during infection. Only immunization with pCry1Ac plus extract conferred a significant protection (up to 47%). This group presented fluctuating antibody peaks during infection and the highest IgG1 and IgM titres. Immunization with extract alone elicited high IgG1 and the highest IgG2a responses after 25 days of infection, while nonimmunized mice presented a poor, mixed-Th1/Th2 response during infection. Sharp peaks of TNFα and IFN-γ occurred immediately after the first immunization with extract, especially in the presence of pCry1Ac, but not after the challenge, while in the control and pCry1Ac-alone groups, cytokines were only detected after the challenge. The data support the protective-adjuvant effect of co-administration of pCry1Ac in cysticercosis. PMID:24484070

  19. Coadministration of protoxin Cry1Ac from Bacillus thuringiensis with metacestode extract confers protective immunity to murine cysticercosis.

    PubMed

    Ibarra-Moreno, S; García-Hernández, A L; Moreno-Fierros, L

    2014-06-01

    The Bacillus thuringiensis Cry1Ac protoxin (pCry1Ac) is a promising mucosal immunogen and adjuvant that induces protective immunity against Naegleria fowleri and malaria infection models. We determined whether pCry1Ac acted as a protective adjuvant against infection with Taenia crassiceps. BALB/C mice were thrice i.p. immunized with (i) pCry1Ac, (ii) metacestode extract, (iii) extract + pCry1Ac or (iv) vehicle, challenged with metacestodes on day 26 and then sacrificed 35 days later. Cysticerci in the peritoneal cavity were counted, while the serum antibody response and cytokines were analysed after immunization and during infection. Only immunization with pCry1Ac plus extract conferred a significant protection (up to 47%). This group presented fluctuating antibody peaks during infection and the highest IgG1 and IgM titres. Immunization with extract alone elicited high IgG1 and the highest IgG2a responses after 25 days of infection, while nonimmunized mice presented a poor, mixed-Th1/Th2 response during infection. Sharp peaks of TNFα and IFN-γ occurred immediately after the first immunization with extract, especially in the presence of pCry1Ac, but not after the challenge, while in the control and pCry1Ac-alone groups, cytokines were only detected after the challenge. The data support the protective-adjuvant effect of co-administration of pCry1Ac in cysticercosis.

  20. Oral Immunization with a Salmonella typhimurium Vaccine Vector Expressing Recombinant Enterotoxigenic Escherichia coli K99 Fimbriae Elicits Elevated Antibody Titers for Protective Immunity

    PubMed Central

    Ascón, Miguel A.; Hone, David M.; Walters, Nancy; Pascual, David W.

    1998-01-01

    Bovine enterotoxigenic Escherichia coli (ETEC) continues to cause mortality in piglets and newborn calves. In an effort to develop a safe and effective vaccine for the prevention of F5+ ETEC infections, a balanced lethal asd+ plasmid carrying the complete K99 operon was constructed and designated pMAK99-asd+. Introduction of this plasmid into an attenuated Salmonella typhimurium Δaro Δasd strain, H683, resulted in strain AP112, which stably expresses E. coli K99 fimbriae. A single oral immunization of BALB/c and CD-1 mice with strain AP112 elicited significant mucosal immunoglobulin A (IgA) titers that remained elevated for >11 weeks. IgA and IgG responses in serum specific for K99 fimbriae were also induced, with a prominent IgG1, as well as IgG2a and IgG2b, titer. To assess the derivation of these antibodies, a K99 isotype-specific B-cell ELISPOT analysis was conducted by using mononuclear cells from the lamina propria of the small intestines (LP), Peyer’s patches (PP), and spleens of vaccinated and control BALB/c mice. This analysis revealed elevated numbers of K99 fimbria-specific IgA-producing cells in the LP, PP, and spleen, whereas elevated K99 fimbria-specific IgG-producing cells were detected only in the PP and spleen. These antibodies were important for protective immunity. One-day-old neonates from dams orally immunized with AP112 were provided passive protection against oral challenge with wild-type ETEC, in contrast to challenged neonates from unvaccinated dams or from dams vaccinated with a control Salmonella vector. These results confirm that oral Salmonella vaccine vectors effectively deliver K99 fimbriae to mucosal inductive sites for sustained elevation of IgA and IgG antibodies and for eliciting protective immunity. PMID:9784559

  1. Protective effect of DNA-mediated immunization with liposome-encapsulated GRA4 against infection of Toxoplasma gondii.

    PubMed

    Chen, Rui; Lu, Shao-Hong; Tong, Qun-Bo; Lou, Di; Shi, Dong-Yan; Jia, Bing-Bing; Huang, Guo-Ping; Wang, Jin-Fu

    2009-07-01

    The dense granule protein 4 (GRA4) is a granular protein from Toxoplasma gondii, and is a candidate for vaccination against this parasite. In this study, the plasmid pcDNA3.1-GRA4 (pGRA4), encoding for the GRA4 antigen, was incorporated by the dehydration-rehydration method into liposomes composed of 16 mmol/L egg phosphatidylcholine (PC), 8 mmol/L dioleoyl phosphatidylethanolamine (DOPE), and 4 mmol/L 1,2-diodeoyl-3-(trimethylammonium) propane (DOTAP). C57BL/6 mice and BALB/c mice were immunized intramuscularly three times with liposome-encapsulated pGRA4 to determine whether DNA immunization could elicit a protective immune response to T. gondii. Enzyme-linked immunosorbent assay (ELISA) of sera from immunized mice showed that liposome-encapsulated pGRA4 generated high levels of IgG antibodies to GRA4. Production of primary interferon (IFN)-gamma and interleukin (IL)-2 in GRA4-stimulated splenocytes from vaccinated mice suggested a modulated Th1-type response. 72.7% of C57BL/6 mice immunized with liposome-encapsulated pGRA4 survived the challenge with 80 tissue cysts of ME49 strain, whereas C57BL/6 mice immunized with pGRA4 had only a survival rate of 54.5%. When immunized BALB/c mice were intraperitoneally challenged with 10(3) tachyzoites of the highly virulent RH strain, the survival time of mice immunized with liposome-encapsulated pGRA4 was markedly longer than that of other groups. Our observations show that liposome-encapsulated pGRA4 enhanced the protective effect against infection of T. gondii. PMID:19585669

  2. Regions of Yersinia pestis V antigen that contribute to protection against plague identified by passive and active immunization.

    PubMed Central

    Hill, J; Leary, S E; Griffin, K F; Williamson, E D; Titball, R W

    1997-01-01

    V antigen of Yersinia pestis is a multifunctional protein that has been implicated as a protective antigen, a virulence factor, and a regulatory protein. A series of V-antigen truncates expressed as glutathione S-transferase (GST) fusion proteins (GST-V truncates) have been cloned and purified to support immunogenicity and functionality studies of V antigen. Immunization studies with GST-V truncates have identified two regions of V antigen that confer protection against Y. pestis 9B (a fully virulent human pneumonic plague isolate) in a mouse model for plague. A minor protective region is located from amino acids 2 to 135 (region I), and a major protective region is found between amino acids 135 and 275 (region II). In addition, analysis of IgG titers following immunization suggested that the major antigenic region of V antigen is located between amino acids 135 and 245. A panel of monoclonal antibodies raised against recombinant V antigen was characterized by Western blotting against GST-V truncates, and epitopes of most of the monoclonal antibodies were mapped to region I or II. Monoclonal antibody 7.3, which recognizes an epitope in region II, passively protected mice against challenge with 12 median lethal doses of Y. pestis GB, indicating that region II encodes a protective epitope. This is the first report of a V-antigen-specific monoclonal antibody that will protect mice against a fully virulent strain of Y. pestis. The combined approach of passive and active immunization has therefore confirmed the importance of the central region of the protein for protection and also identified a previously unknown protective region at the N terminus of V antigen. PMID:9353022

  3. Extraordinarily few organisms of a live recombinant BCG vaccine against tuberculosis induce maximal cell-mediated and protective immunity.

    PubMed

    Horwitz, Marcus A; Harth, Günter; Dillon, Barbara Jane; Maslesa-Galić, Sasa

    2006-01-23

    In previous studies, we have described a live recombinant BCG vaccine (rBCG30) overexpressing the 30 kDa major secretory protein of Mycobacterium tuberculosis that induces greater protective immunity against tuberculosis than the current vaccine in the demanding guinea pig model of pulmonary tuberculosis. In this study, we have investigated the impact of vaccine dose on the development of cell-mediated and protective immunity in the guinea pig model. We found that the protective efficacy against M. tuberculosis aerosol challenge of both BCG and rBCG30 was essentially dose-independent over a dose range of 10(1)-10(6) live organisms. As previously observed, rBCG30 was more potent, reducing colony-forming units (CFU) below the level observed in animals immunized with the parental BCG vaccine by 0.7 logs in the lungs and 1.0 logs in the spleen (P<0.0001). To gain a better understanding of the influence of dose on bacterial clearance and immunity, we assessed animals immunized with 10(1), 10(3), or 10(6)CFU of rBCG30. The higher the dose, the higher the peak CFU level achieved in animal organs. However, whereas humoral immune responses to the 30 kDa protein reflected the disparate CFU levels, cell-mediated immune responses did not; high and low doses of rBCG30 ultimately induced comparable peak lymphocyte proliferative responses and cutaneous delayed-type hypersensitivity responses to the 30 kDa protein. We estimate that the amount of the 30 kDa protein required to induce a strong cell-mediated immune response when delivered via 10 rBCG30 organisms is about 9 orders of magnitude less than that required when the protein is delivered in a conventional protein/adjuvant vaccine. This study demonstrates that a very low inoculum of rBCG30 organisms has the capacity to induce strong protective immunity against tuberculosis and that rBCG30 is an extremely potent delivery system for mycobacterial antigens.

  4. The Role of Age and Exposure to Plasmodium falciparum in the Rate of Acquisition of Naturally Acquired Immunity: A Randomized Controlled Trial

    PubMed Central

    Guinovart, Caterina; Dobaño, Carlota; Bassat, Quique; Nhabomba, Augusto; Quintó, Llorenç; Manaca, Maria Nélia; Aguilar, Ruth; Rodríguez, Mauricio H.; Barbosa, Arnoldo; Aponte, John J.; Mayor, Alfredo G.; Renom, Montse; Moraleda, Cinta; Roberts, David J.; Schwarzer, Evelin; Le Souëf, Peter N.; Schofield, Louis; Chitnis, Chetan E.; Doolan, Denise L.; Alonso, Pedro L.

    2012-01-01

    Background The rate of acquisition of naturally acquired immunity (NAI) against malaria predominantly depends on transmission intensity and age, although disentangling the effects of these is difficult. We used chemoprophylaxis to selectively control exposure to P. falciparum during different periods in infancy and explore the effect of age in the build-up of NAI, measured as risk of clinical malaria. Methods and Findings A three-arm double-blind randomized placebo-controlled trial was conducted in 349 infants born to Mozambican HIV-negative women. The late exposure group (LEG) received monthly Sulfadoxine-Pyrimethamine (SP) plus Artesunate (AS) from 2.5–4.5 months of age and monthly placebo from 5.5–9.5 months; the early exposure group (EEG) received placebo from 2.5–4.5 months and SP+AS from 5.5–9.5 months; and the control group (CG) received placebo from 2.5–9.5 months. Active and passive case detection (PCD) were conducted from birth to 10.5 and 24 months respectively. The primary endpoint was time to first or only episode of malaria in the second year detected by PCD. The incidence of malaria during the second year was of 0.50, 0.51 and 0.35 episodes/PYAR in the LEG, EEG and CG respectively (p = 0.379 for the adjusted comparison of the 3 groups). The hazard ratio of the adjusted comparison between the LEG and the CG was 1.38 (0.83–2.28, p = 0.642) and that between the EEG and the CG was 1.35 (0.81–2.24, p = 0.743). Conclusions After considerably interfering with exposure during the first year of life, there was a trend towards a higher risk of malaria in the second year in children who had received chemoprophylaxis, but there was no significant rebound. No evidence was found that the age of first exposure to malaria affects the rate of acquisition of NAI. Thus, the timing of administration of antimalarial interventions like malaria vaccines during infancy does not appear to be a critical determinant. Trial Registration Clinical

  5. Muscles provide protection during microbial infection by activating innate immune response pathways in Drosophila and zebrafish

    PubMed Central

    Chatterjee, Arunita; Roy, Debasish; Patnaik, Esha

    2016-01-01

    ABSTRACT Muscle contraction brings about movement and locomotion in animals. However, muscles have also been implicated in several atypical physiological processes including immune response. The role of muscles in immunity and the mechanism involved has not yet been deciphered. In this paper, using Drosophila indirect flight muscles (IFMs) as a model, we show that muscles are immune-responsive tissues. Flies with defective IFMs are incapable of mounting a potent humoral immune response. Upon immune challenge, the IFMs produce anti-microbial peptides (AMPs) through the activation of canonical signaling pathways, and these IFM-synthesized AMPs are essential for survival upon infection. The trunk muscles of zebrafish, a vertebrate model system, also possess the capacity to mount an immune response against bacterial infections, thus establishing that immune responsiveness of muscles is evolutionarily conserved. Our results suggest that physiologically fit muscles might boost the innate immune response of an individual. PMID:27101844

  6. Colonization of Phlebotomus papatasi changes the effect of pre-immunization with saliva from lack of protection towards protection against experimental challenge with Leishmania major and saliva

    PubMed Central

    2011-01-01

    Background Sand fly saliva has been postulated as a potential vaccine or as a vaccine component within multi component vaccine against leishmaniasis. It is important to note that these studies were performed using long-term colonized Phlebotomus papatasi. The effect of sand flies colonization on the outcome of Leishmania infection is reported. Results While pre-immunization of mice with salivary gland homogenate (SGH) of long-term colonized (F5 and beyond) female Phlebotomus papatasi induced protection against Leishmania major co-inoculated with the same type of SGH, pre-immunization of mice with SGH of recently colonized (F2 and F3) female P. papatasi did not confer protection against L. major co-inoculated with the same type of SGH. Our data showed for the first time that a shift from lack of protection to protection occurs at the fourth generation (F4) during the colonization process of P. papatasi. Conclusion For the development of a sand fly saliva-based vaccine, inferences based on long-term colonized populations of sand flies should be treated with caution as colonization of P. papatasi appears to modulate the outcome of L. major infection from lack of protection to protection. PMID:21726438

  7. Immunization with the cysteine proteinase Ldccys1 gene from Leishmania (Leishmania) chagasi and the recombinant Ldccys1 protein elicits protective immune responses in a murine model of visceral leishmaniasis.

    PubMed

    Ferreira, Josie Haydée L; Gentil, Luciana Girotto; Dias, Suzana Souza; Fedeli, Carlos Eduardo C; Katz, Simone; Barbiéri, Clara Lúcia

    2008-01-30

    The gene Ldccys1 encoding a cysteine proteinase of 30 kDa from Leishmania (Leishmania) chagasi, as well as the recombinant cysteine proteinase rLdccys1, obtained by cloning and expression of the Ldccys1 gene in the pHIS vector, were used to evaluate their ability to induce immune protective responses in BALB/c mice against L. (L.) chagasi infection. Mice were immunized subcutaneously with rLdccys1 plus Bacille Calmette Guerin (BCG) or Propionibacterium acnes as adjuvants or intramuscularly with a plasmid carrying the Ldccys1 gene (Ldccys1/pcDNA3) and CpG ODN as the adjuvant, followed by a booster with rLdccys1 plus CpG ODN. Two weeks after immunization the animals were challenged with 1 x 10(7) amastigotes of L. (L.) chagasi. Both immunization protocols induced significant protection against L. (L.) chagasi infection as shown by a very low parasite load in the spleen of immunized mice compared to the non-immunized controls. However, DNA immunization was 10-fold more protective than immunization with the recombinant protein. Whereas rLdccys1 induced a significant secretion of IFN-gamma and nitric oxide (NO), animals immunized with the Ldccys1 gene increased the production of IgG2a antibodies, IFN-gamma and NO. These results indicated that protection triggered by the two immunization protocols was correlated to a predominant Th1 response.

  8. Plasmodium falciparum synthetic LbL microparticle vaccine elicits protective neutralizing antibody and parasite-specific cellular immune responses

    PubMed Central

    Powell, Thomas J.; Tang, Jie; DeRome, Mary E.; Mitchell, Robert A.; Jacobs, Andrea; Deng, Yanhong; Palath, Naveen; Cardenas, Edwin; Boyd, James G.; Nardin, Elizabeth

    2013-01-01

    Epitopes of the circumsporozoite (CS) protein of Plasmodium falciparum, the most pathogenic species of the malaria parasite, have been shown to elicit protective immunity in experimental animals and human volunteers. The mechanisms of immunity include parasite-neutralizing antibodies that can inhibit parasite motility in the skin at the site of infection and in the bloodstream during transit to the hepatocyte host cell and also block interaction with host cell receptors on hepatocytes. In addition, specific CD4+ and CD8+ cellular mechanisms target the intracellular hepatic forms, thus preventing release of erythrocytic stage parasites from the infected hepatocyte and the ensuing blood stage cycle responsible for clinical disease. An innovative method for producing particle vaccines, layer-by-layer (LbL) fabrication of polypeptide films on solid CaCO3 cores, was used to produce synthetic malaria vaccines containing a tri-epitope CS peptide T1BT* comprising the antibody epitope of the CS repeat region (B) and two T-cell epitopes, the highly conserved T1 epitope and the universal epitope T*. Mice immunized with microparticles loaded with T1BT* peptide developed parasite-neutralizing antibodies and malaria-specific T-cell responses including cytotoxic effector T-cells. Protection from liver stage infection following challenge with live sporozoites from infected mosquitoes correlated with neutralizing antibody levels. Although some immunized mice with low or undetectable neutralizing antibodies were also protected, depletion of T-cells prior to challenge resulted in the majority of mice remaining resistant to challenge. In addition, mice immunized with microparticles bearing only T-cell epitopes were not protected, demonstrating that cellular immunity alone was not sufficient for protective immunity. Although the microparticles without adjuvant were immunogenic and protective, a simple modification with the lipopeptide TLR2 agonist Pam3Cys increased the potency and

  9. Plasmodium falciparum synthetic LbL microparticle vaccine elicits protective neutralizing antibody and parasite-specific cellular immune responses.

    PubMed

    Powell, Thomas J; Tang, Jie; Derome, Mary E; Mitchell, Robert A; Jacobs, Andrea; Deng, Yanhong; Palath, Naveen; Cardenas, Edwin; Boyd, James G; Nardin, Elizabeth

    2013-04-01

    Epitopes of the circumsporozoite (CS) protein of Plasmodium falciparum, the most pathogenic species of the malaria parasite, have been shown to elicit protective immunity in experimental animals and human volunteers. The mechanisms of immunity include parasite-neutralizing antibodies that can inhibit parasite motility in the skin at the site of infection and in the bloodstream during transit to the hepatocyte host cell and also block interaction with host cell receptors on hepatocytes. In addition, specific CD4+ and CD8+ cellular mechanisms target the intracellular hepatic forms, thus preventing release of erythrocytic stage parasites from the infected hepatocyte and the ensuing blood stage cycle responsible for clinical disease. An innovative method for producing particle vaccines, layer-by-layer (LbL) fabrication of polypeptide films on solid CaCO3 cores, was used to produce synthetic malaria vaccines containing a tri-epitope CS peptide T1BT comprising the antibody epitope of the CS repeat region (B) and two T-cell epitopes, the highly conserved T1 epitope and the universal epitope T. Mice immunized with microparticles loaded with T1BT peptide developed parasite-neutralizing antibodies and malaria-specific T-cell responses including cytotoxic effector T-cells. Protection from liver stage infection following challenge with live sporozoites from infected mosquitoes correlated with neutralizing antibody levels. Although some immunized mice with low or undetectable neutralizing antibodies were also protected, depletion of T-cells prior to challenge resulted in the majority of mice remaining resistant to challenge. In addition, mice immunized with microparticles bearing only T-cell epitopes were not protected, demonstrating that cellular immunity alone was not sufficient for protective immunity. Although the microparticles without adjuvant were immunogenic and protective, a simple modification with the lipopeptide TLR2 agonist Pam3Cys increased the potency and

  10. Recombinant Toxoplasma gondii phosphoglycerate mutase 2 confers protective immunity against toxoplasmosis in BALB/c mice

    PubMed Central

    Wang, Hai-Long; Wen, Li-Min; Pei, Yan-Jiang; Wang, Fen; Yin, Li-Tian; Bai, Ji-Zhong; Guo, Rui; Wang, Chun-Fang; Yin, Guo-Rong

    2016-01-01

    Toxoplasmosis is one of the most widespread zoonoses worldwide. It has a high incidence and can result in severe disease in humans and livestock. Effective vaccines are needed to limit and prevent infection with Toxoplasma gondii. In this study, we evaluated the immuno-protective efficacy of a recombinant Toxoplasma gondii phosphoglycerate mutase 2 (rTgPGAM 2) against T. gondii infection in BALB/c mice. We report that the mice nasally immunised with rTgPGAM 2 displayed significantly higher levels of special IgG antibodies against rTgPGAM 2 (including IgG1, IgG2a and IgAs) and cytokines (including IFN-γ, IL-2 and IL-4) in their blood sera and supernatant of cultured spleen cells compared to those of control animals. In addition, an increased number of spleen lymphocytes and enhanced lymphocyte proliferative responses were observed in the rTgPGAM 2-immunised mice. After chronic infection and lethal challenge with the highly virulent T. gondii RH strain by oral gavage, the survival time of the rTgPGAM 2-immunised mice was longer (P < 0.01) and the survival rate (70%) was higher compared with the control mice (P < 0.01). The reduction rate of brain and liver tachyzoites in rTgPGAM 2-vaccinated mice reached approximately 57% and 69% compared with those of the control mice (P < 0.01). These results suggest that rTgPGAM 2 can generate protective immunity against T. gondii infection in BALB/c mice and may be a promising antigen in the further development of an effective vaccine against T. gondii infection. PMID:26984115

  11. Custom-engineered chimeric foot-and-mouth disease vaccine elicits protective immune responses in pigs.

    PubMed

    Blignaut, Belinda; Visser, Nico; Theron, Jacques; Rieder, Elizabeth; Maree, Francois F

    2011-04-01

    Chimeric foot-and-mouth disease viruses (FMDV) of which the antigenic properties can be readily manipulated is a potentially powerful approach in the control of foot-and-mouth disease (FMD) in sub-Saharan Africa. FMD vaccine application is complicated by the extensive variability of the South African Territories (SAT) type viruses, which exist as distinct genetic and antigenic variants in different geographical regions. A cross-serotype chimeric virus, vKNP/SAT2, was engineered by replacing the external capsid-encoding region (1B-1D/2A) of an infectious cDNA clone of the SAT2 vaccine strain, ZIM/7/83, with that of SAT1 virus KNP/196/91. The vKNP/SAT2 virus exhibited comparable infection kinetics, virion stability and antigenic profiles to the KNP/196/91 parental virus, thus indicating that the functions provided by the capsid can be readily exchanged between serotypes. As these qualities are necessary for vaccine manufacturing, high titres of stable chimeric virus were obtained. Chemically inactivated vaccines, formulated as double-oil-in-water emulsions, were produced from intact 146S virion particles of both the chimeric and parental viruses. Inoculation of guinea pigs with the respective vaccines induced similar antibody responses. In order to show compliance with commercial vaccine requirements, the vaccines were evaluated in a full potency test. Pigs vaccinated with the chimeric vaccine produced neutralizing antibodies and showed protection against homologous FMDV challenge, albeit not to the same extent as for the vaccine prepared from the parental virus. These results provide support that chimeric vaccines containing the external capsid of field isolates can be successfully produced and that they induce protective immune responses in FMD host species. PMID:21177923

  12. Vaccination Method Affects Immune Response and Bacterial Growth but Not Protection in the Salmonella Typhimurium Animal Model of Typhoid.

    PubMed

    Kinnear, Clare L; Strugnell, Richard A

    2015-01-01

    Understanding immune responses elicited by vaccines, together with immune responses required for protection, is fundamental to designing effective vaccines and immunisation programs. This study examines the effects of the route of administration of a live attenuated vaccine on its interactions with, and stimulation of, the murine immune system as well as its ability to increase survival and provide protection from colonisation by a virulent challenge strain. We assess the effect of administration method using the murine model for typhoid, where animals are infected with S. Typhimurium. Mice were vaccinated either intravenously or orally with the same live attenuated S. Typhimurium strain and data were collected on vaccine strain growth, shedding and stimulation of antibodies and cytokines. Following vaccination, mice were challenged with a virulent strain of S. Typhimurium and the protection conferred by the different vaccination routes was measured in terms of challenge suppression and animal survival. The main difference in immune stimulation found in this study was the development of a secretory IgA response in orally-vaccinated mice, which was absent in IV vaccinated mice. While both strains showed similar protection in terms of challenge suppression in systemic organs (spleen and liver) as well as survival, they differed in terms of challenge suppression of virulent pathogens in gut-associated organs. This difference in gut colonisation presents important questions around the ability of vaccines to prevent shedding and transmission. These findings demonstrate that while protection conferred by two vaccines can appear to be the same, the mechanisms controlling the protection can differ and have important implications for infection dynamics within a population.