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Humoral Response (humoral + response)
Selected AbstractsORIGINAL ARTICLE: IL-6 as a Regulatory Factor of the Humoral Response During PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2008Valeria Dubinsky Problem, Regulatory factors seem to be essential to achieve transition from implantation window to placental vascularization. A novel function of interleukin (IL)-6 in the promotion of Th2 differentiation and inhibition of Th1 polarization has been demonstrated. Considering that Th2 response promotes antibody synthesis, we postulate that IL-6 could be modulating the quality of this response during pregnancy by increasing the proportion of blocking asymmetric antibodies. Method of study, We investigated expression of blocking-asymmetric-IgG during pregnancy of CBA/J × DBA/2 abortion model treated with IL-6, with regards to CBA/J × BALB/c. We also determined asymmetric-IgG production in IL-6-deficient pregnant mice. Results, We found that IL-6 treatment increased asymmetric-IgG in multiparous placentas from abortion combination whereas diminished abortion rate. Moreover, asymmetric-IgG proportion was diminished in sera from IL-6-deficient pregnant mice. Conclusion, Modulation of asymmetric antibody synthesis could be another mechanism implicated in the beneficial effect of IL-6 in prevention of murine recurrent abortion. [source] Humoral responses after influenza vaccination are severely reduced in patients with rheumatoid arthritis treated with rituximab,ARTHRITIS & RHEUMATISM, Issue 1 2010Sander van Assen Objective For patients with rheumatoid arthritis (RA), yearly influenza vaccination is recommended. However, its efficacy in patients treated with rituximab is unknown. The objectives of this study were to investigate the efficacy of influenza vaccination in RA patients treated with rituximab and to investigate the duration of the possible suppression of the humoral immune response following rituximab treatment. We also undertook to assess the safety of influenza vaccination and the effects of previous influenza vaccination. Methods Trivalent influenza subunit vaccine was administered to 23 RA patients who had received rituximab (4,8 weeks after rituximab for 11 patients [the early rituximab subgroup] and 6,10 months after rituximab for 12 patients [the late rituximab subgroup]), 20 RA patients receiving methotrexate (MTX), and 29 healthy controls. Levels of antibodies against the 3 vaccine strains were measured before and 28 days after vaccination using hemagglutination inhibition assay. The Disease Activity Score in 28 joints (DAS28) was used to assess RA activity. Results Following vaccination, geometric mean titers (GMTs) of antiinfluenza antibodies significantly increased for all influenza strains in the MTX-treated group and in healthy controls, but for no strains in the rituximab-treated group. However, in the late rituximab subgroup, a rise in GMT for the A/H3N2 and A/H1N1 strains was demonstrated, in the absence of a repopulation of CD19+ cells at the time of vaccination. Seroconversion and seroprotection occurred less often in the rituximab-treated group than in the MTX-treated group for the A/H3N2 and A/H1N1 strains, while seroprotection occurred less often in the rituximab-treated group than in the healthy controls for the A/H1N1 strain. Compared with unvaccinated patients in the rituximab-treated group, previously vaccinated patients in the rituximab-treated group had higher pre- and postvaccination GMTs for the A/H1N1 strain. The DAS28 did not change after vaccination. Conclusion Rituximab reduces humoral responses following influenza vaccination in RA patients, with a modestly restored response 6,10 months after rituximab administration. Previous influenza vaccination in rituximab-treated patients increases pre- and postvaccination titers. RA activity was not influenced. [source] Cerebrospinal fluid and serum antibodies against neurofilaments in patients with amyotrophic lateral sclerosisEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2010L. Fialová Background:, The aim of the study was to assess autoimmune involvement in amyotrophic lateral sclerosis (ALS). Methods:, We measured IgG antibodies against light (NFL) and medium (NFM) subunits of neurofilaments using ELISA in paired cerebrospinal fluid (CSF) and serum samples from 38 ALS patients and 20 controls. Results:, Serum levels of anti-NFL were higher in ALS patients than in controls (P < 0.005). Serum anti-NFL antibodies and intrathecal anti-NFM antibodies were related to patient disability (serum anti-NFL: P < 0.05; intrathecal anti-NFM: P < 0.05). Anti-NFL levels were significantly correlated with anti-NFM levels in ALS (P < 0.001) and the control group (P < 0.0001) in the CSF, but not in serum. Anti-NFL and anti-NFM antibodies significantly correlated between serum and CSF in the ALS group (anti-NFL: P < 0.0001; anti-NFM: P < 0.001) and in the control group (anti-NFL: P < 0.05; anti-NFM: P < 0.05). Conclusions:, Autoimmune humoral response to neurocytoskeletal proteins is associated with ALS. [source] Antibody response to Candida albicans cell wall antigensFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2004José L López-Ribot Abstract The cell wall of Candida albicans is not only the structure where many essential biological functions reside but is also a significant source of candidal antigens. The major cell wall components that elicit a response from the host immune system are proteins and glycoproteins, the latter being predominantly mannoproteins. Both carbohydrate and protein moieties are able to trigger immune responses. Proteins and glycoproteins exposed at the most external layers of the wall structure are involved in several types of interactions of fungal cells with the exocellular environment. Thus, coating of fungal cells with host antibodies has the potential to profoundly influence the host,parasite interaction by affecting antibody-mediated functions such as opsonin-enhanced phagocytosis and blocking the binding activity of fungal adhesins to host ligands. In this review we examine various members of the protein and glycoprotein fraction of the C. albicans cell wall that elicit an antibody response in vivo. Some of the studies demonstrate that certain cell wall antigens and anti-cell wall antibodies may be the basis for developing specific and sensitive serologic tests for the diagnosis of candidiasis, particularly the disseminated form. In addition, recent studies have focused on the potential of antibodies against the cell wall protein determinants in protecting the host against infection. Hence, a better understanding of the humoral response triggered by the cell wall antigens of C. albicans may provide the basis for the development of (i) effective procedures for the serodiagnosis of disseminated candidiasis, and (ii) novel prophylactic (vaccination) and therapeutic strategies to control this type of infections. [source] Structure and biology of complement protein C3, a connecting link between innate and acquired immunityIMMUNOLOGICAL REVIEWS, Issue 1 2001Arvind Sahu Summary: Complement protein C3 is a central molecule in the complement system whose activation is essential for all the important functions performed by this system. After four decades of research it is now well established that C3 functions like a double-edged sword: on the one hand it promotes phagocytosis, supports local inflammatory responses against pathogens, and instructs the adaptive immune response to select the appropriate antigens for a humoral response; on the other hand its unregulated activation leads to host cell damage. In addition, its interactions with the proteins of foreign pathogens may provide a mechanism by which these microorganisms evade complement attack. Therefore, a clear knowledge of the molecule and its interactions at the molecular level not only may allow the rational design of molecular adjuvants but may also lead to the development of complement inhibitors and new therapeutic agents against infectious diseases. A.S. is a Wellcome Trust Overseas Senior Research Fellow in Biomedical Science in India. This research was supported by National Institutes of Health grants AI 30040, GM 56698, HL28220, and AI 48487. [source] The Flavobacterium psychrophilum OmpA, an outer membrane glycoprotein, induces a humoral response in rainbow troutJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2007F. Dumetz Abstract Aims:, The purpose of this study was to characterize OmpA, a major glycoprotein isolated from the membrane fraction of Flavobacterium psychrophilum, and to evaluate its potential as antigenic unit in a possible vaccine. Methods and Results:, The expression product of ompA is a 465-amino-acid protein precursor that contains a 21-amino acid signal peptide and has overall homology (up to 60% identity) with similarly sized proteins of some bacteria belonging to the Flavobacteriaceae family. The carboxy-terminal region contains the ,OmpA/MotB' domain/signature and five putative ,Thrombospondin type 3 repeats' domains have been identified in the central region. OmpA was clearly detected in the outer membrane fraction and its surface exposure was demonstrated. OmpA is one of the immunodominant antigens and binding of specific anti-OmpA antibodies lead to cell lysis in the presence of complement. Fish immunized with OmpA emulsified with Freund's adjuvant developed a high antibody titter. Conclusions:, Collectively, the data obtained here indicate that OmpA may be involved in Fl. psychrophilum/host cell interactions and appears to be a potential immunogen for a vaccine. Significance and Impact of the Study:, This study is one step in the direction of understanding pathogenesis of Fl. psychrophilum and development of future vaccine. [source] Relevance of incubation temperature for Vibrio salmonicida vaccine productionJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2002D.J. Colquhoun Aims:,To investigate the relationships between water temperature, bacterial growth, virulence and antigen expression in Vibrio salmonicida, the causal agent of cold water vibriosis in Atlantic salmon (Salmo salar L.). Methods and Results:,The significance of sea temperature was investigated using historical clinical and oceanographic data. An upper threshold for disease of approx. 10°C was established. The effects of culture temperature and media type on bacterial growth were studied on solid and in liquid media. The highest rates of cell division were identified at 15°C on solid media and 10°C in liquid media. Outer membrane protein (OMP) expression and serological response in Atlantic salmon were studied using sodium dodecyl sulphate-polyacrylamide gel electrophoresis, Western blotting and enzyme-linked immunosorbent assay. A novel 76-kDa OMP produced in unshaken cultures at 10°C was not found to stimulate a specific humoral response. Conclusions:,Diagnostic agar plate-based incubation of suspected V. salmonicida should be carried out at 15°C. High yield broth cultures for vaccine production should be incubated at 10°C or lower. Significance and Impact of the Study:,This study is, to the best of our knowledge, the first to identify different optimal temperatures in a bacterial species cultured on physically different types of media. The evidence presented suggests that V. salmonicida and possibly other bacteria destined for vaccine use in poikilothermic organisms should be cultured at temperatures consistent with that at which disease occurs. [source] Strain-dependent activation of the mouse immune response is correlated with Porphyromonas gingivalis -induced experimental periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 11 2009Asaf Wilensky Abstract Aims: To evaluate the effect of oral infection with three Porphyromonas gingivalis strains on alveolar bone loss (ABL) and its correlation with the mouse immune response. Materials and Methods: Mice were orally infected with P. gingivalis strains 381, 33277 and 53977. After 42 days, maxillae were analysed for ABL using micro-computed tomography and the serum for anti- P.gingivalis IgG1 and IgG2a levels. The cytokine response to P. gingivalis was tested using the subcutaneous chamber model. Results: The P. gingivalis 53977-infected group showed the highest ABL, which was significantly different from all other groups (p<0.001). In addition, the humoral response to P. gingivalis 53977 was significantly lower than the response to P. gingivalis 381 and 33277 (p0.01). The IgG2a/IgG1 ratio was higher in the P. gingivalis 33277-infected group (1.6) compared with the P. gingivalis 381-infected group (0.51). Four days post-infection, interleukin (IL)-1, levels remained significantly higher in the P. gingivalis 53977-infected group only (1198.2±260.0, p<0.05), while IL-4 levels remained significantly higher in the P. gingivalis 381-infected group (265.8±131.6, p<0.05). Conclusions: The high levels of ABL induced by P. gingivalis 53977 were inversely correlated with the humoral response to this bacterium. In addition, ABL was correlated with an elevated pro-inflammatory response. [source] Systemic and mucosal antibody response in tilapia, Oreochromis niloticus (L.), following immunization with Flavobacterium columnareJOURNAL OF FISH DISEASES, Issue 10 2004L D Grabowski Abstract Specific antibody responses to Flavobacterium columnare (isolate ATCC 23463T) were characterized in plasma and mucus of tilapia following intraperitoneal (i.p.) injection or immersion immunization with formalin-killed sonicated or whole cell preparations. Fish (30 per treatment) received a primary immunization and were booster immunized 4 weeks later. An enzyme-linked immunosorbent assay was developed for detection and quantification of specific anti- F. columnare antibody, and it was found that formalin-killed sonicated cells in Freund's complete adjuvant (FCA) injected i.p. stimulated a significant systemic antibody response within 2 weeks (mean titre 11 200) which increased to 30 600 following secondary immunization. At 10 weeks post-immunization, the mean titre remained significantly elevated above the controls. Antibodies were also observed in cutaneous mucus of fish immunized i.p. with formalin-killed sonicated cells in FCA at 6 and 8 weeks post-immunization (mean titres 67 and 33, respectively). Although some individual fish responded, mean plasma and cutaneous mucus antibody titres were not significantly greater than controls in any of the other treatment groups. The results of this study demonstrate that tilapia can mount a significant humoral response in plasma and cutaneous mucus to F. columnare, but i.p. immunization with FCA is required to elicit this response. [source] Experimental Cryptobia salmositica (Kinetoplastida) infections in Atlantic salmon, Salmo salar L.: cell-mediated and humoral immune responses against the pathogenic and vaccine strains of the parasiteJOURNAL OF FISH DISEASES, Issue 5 2002B F Ardelli Hatchery-reared Atlantic salmon, Salmo salar L., were vaccinated intraperitoneally (i.p.) with a live attenuated Cryptobia salmositica vaccine (either 100 000 or 5000 parasites fish,1) and 4 weeks later were challenged with the parasite (either 100 000 or 5000 parasites fish,1). Unvaccinated, infected salmon had high parasitaemias and were anaemic. Fish given a high dose (100 000 parasites fish,1) had higher parasitaemias than fish given the lower dose. Vaccinated fish had low parasitaemias and a mild anaemia, but recovered quickly after challenge. Complement-fixing antibody increased in vaccinated fish after challenge and was highest at 2 weeks post-challenge. The cell-mediated response (both T cells and B cells) was depressed in infected fish until 4 weeks after infection. In vaccinated fish, the humoral response (i.e. B-lymphocytes) was greater than the cell-mediated response (i.e. T-lymphocytes). In contrast, infected fish had a greater cell-mediated than humoral immune response. [source] Expression and immunogenicity of NY-ESO-1 in hepatocellular carcinomaJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 8 2006Shinichiro Nakamura Abstract Background and Aim:, The present study was designed to investigate the expression of and humoral response against NY-ESO-1 in patients with hepatocellular carcinoma and to analyze the relationship between expression of NY-ESO-1 mRNA and clinicopathological features. Methods:, NY-ESO-1 mRNA and protein expression in surgically resected hepatocellular carcinoma specimens, adjacent non-cancerous liver and non-tumor bearing liver were examined by reverse transcription-polymerase chain reaction and immunohistochemical staining using a monoclonal antibody against NY-ESO-1 (ES121), respectively. The antibody response to NY-ESO-1 was examined by enzyme-linked immunosorbent assay using recombinant NY-ESO-1 protein. Results:,NY-ESO-1 mRNA was detected in 18 of 41 (43.9%) hepatocellular carcinomas. No NY-ESO-1 mRNA was expressed in 41 paired non-cancerous specimens and 18 specimens histologically diagnosed as liver cirrhosis or chronic hepatitis. Immunohistochemistry revealed heterogeneous expression of NY-ESO-1 protein in three of 18 NY-ESO-1 mRNA-positive hepatocellular carcinomas. None of 23 NY-ESO-1 mRNA-negative hepatocellular carcinomas expressed NY-ESO-1 protein. Antibody against NY-ESO-1 protein was detected in two of 92 patients with hepatocellular carcinoma. Both of these patients had tumors invading main branches of the portal vein. Conclusions:, The present study has demonstrated the expression of NY-ESO-1 mRNA in hepatocellular carcinoma and NY-ESO-1 antibody production in patients with advanced hepatocellular carcinoma. Although the enhancement of NY-ESO-1 protein expression and the activation of immune response of the patients with hepatocellular carcinoma are necessary, NY-ESO-1 has the potential to be a good target molecule for immunotherapy against advanced hepatocellular carcinoma. [source] Effect of vaccination with recombinant modified vaccinia virus Ankara expressing structural and regulatory genes of SIVmacJ5 on the kinetics of SIV replication in cynomolgus monkeysJOURNAL OF MEDICAL PRIMATOLOGY, Issue 4 2001Donatella R.M. Negri The efficacy of a multicomponent vaccination with modified vaccinia Ankara constructs (rMVA) expressing structural and regulatory genes of simian immunodeficiency virus (SIVmac251/32H/J5) was investigated in cynomolgus monkeys, following challenge with a pathogenic SIV. Vaccination with rMVA-J5 performed at week 0, 12, and 24 induced a moderate proliferative response to whole SIV, a detectable humoral response to all but Nef SIV antigens, and failed to induce neutralizing antibodies. Two months after the last boost, the monkeys were challenged intravenously with 50 MID50 of SIVmac251. All control monkeys, previously inoculated with non-recombinant MVA, were infected by week two and seroconverted by weeks four to eight. In contrast a sharp increase of both humoral and proliferative responses at two weeks post-challenge was observed in vaccinated monkeys compared to control monkeys. Although all vaccinated monkeys were infected, vaccination with rMVA-J5 appeared to partially control viral replication during the acute and late phase of infection as judged by cell- and plasma-associated viral load. [source] Cellular and humoral immune responses to measles in immune adults re-immunized with measles vaccineJOURNAL OF MEDICAL VIROLOGY, Issue 2 2003Rosa Maria Wong-Chew Abstract The objective of this study was to characterize the kinetics of the cellular and humoral immune responses elicited by measles vaccine given to previously immune adults. The cellular and humoral immune responses to measles were measured in seven healthy adults, before vaccination and at 1, 2, 3, and 4 weeks and 3 months after vaccination, using measles-specific T-cell proliferation and plaque reduction neutralization assays. All study subjects had detectable measles antibodies, but only six (85%) showed protective titers, defined as >1:120, before immunization. However measles-specific T-cell proliferation was not detectable before vaccination in any of the subjects. The six subjects with protective titers showed a positive stimulation index (SI) of >3.0 within the first 4 weeks after vaccination, an SI of 5 at the 4th week, and an SI of 3 at 3 months after vaccination. The subject with a low antibody titer (1:99) before vaccination developed a high SI at 3 months after vaccination. This subject was the only participant whose neutralizing antibody titers increased more than 4-fold by 3 months after vaccination. No significant increases in geometric mean titers were detected in the other six subjects during the follow-up period. These data suggest that high measles antibody titers interfere with the humoral response in subjects who receive a booster immunization, whereas the cellular response is boosted at least transiently, after revaccination. J. Med. Virol. 70: 276,280, 2003. © 2003 Wiley-Liss, Inc. [source] Basal replication of hepatitis C virus in nude mice harboring human tumorJOURNAL OF MEDICAL VIROLOGY, Issue 3 2002Patrick Labonté Abstract Hepatitis C virus (HCV) can infect and propagate in humans and chimpanzees. Whereas the chimpanzee has been used as an animal model for infection, ethical considerations, conservation, and the prohibitively high cost preclude progress for experimental research on the biology of the virus. The development of a small animal model for HCV infection is thus desirable to facilitate studies on the infectious cycle of the virus and for the evaluation of drugs for the treatment of HCV infections in humans. As an alternative to the chimpanzee model, we have established a model based on ex vivo infection of orthotopically-implanted human hepatocellular carcinoma cells (HCC) in athymic nude mice. The results show that up to 42 days post-infection, HCV RNA was present in the tumor cells as well as in the liver and serum of infected mice. Furthermore, a direct correlation between size of the tumor and the presence of HCV RNA in the liver was observed, which is concordant with the finding that HCV RNA was detectable only in mice harboring human tumor. Immunohistochemistry analysis of infected liver specimens showed cells expressing the HCV encoded NS5B protein. A few mice developed a humoral response against the nonstructural viral proteins, providing further evidence for expression of these proteins during viral infection. In summary, these results suggest that mice harboring orthotopic tumors support a basal level of HCV replication in vivo. J. Med. Virol. 66:312-319, 2002. © 2002 Wiley-Liss, Inc. [source] Quantitative mouse model of implant-associated osteomyelitis and the kinetics of microbial growth, osteolysis, and humoral immunity,JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2008Dan Li Abstract Although osteomyelitis (OM) remains a serious problem in orthopedics, progress has been limited by the absence of an in vivo model that can quantify the bacterial load, metabolic activity of the bacteria over time, immunity, and osteolysis. To overcome these obstacles, we developed a murine model of implant-associated OM in which a stainless steel pin is coated with Staphylococcus aureus and implanted transcortically through the tibial metaphysis. X-ray and micro-CT demonstrated concomitant osteolysis and reactive bone formation, which was evident by day 7. Histology confirmed all the hallmarks of implant-associated OM, namely: osteolysis, sequestrum formation, and involucrum of Gram-positive bacteria inside a biofilm within necrotic bone. Serology revealed that mice mount a protective humoral response that commences with an IgM response after 1 week, and converts to a specific IgG2b response against specific S. aureus proteins by day 11 postinfection. Real-time quantitative PCR (RTQ-PCR) for the S. aureus specific nuc gene determined that the peak bacterial load occurs 11 days postinfection. This coincidence of decreasing bacterial load with the generation of specific antibodies is suggestive of protective humoral immunity. Longitudinal in vivo bioluminescent imaging (BLI) of luxA-E transformed S. aureus (Xen29) combined with nuc RTQ-PCR demonstrated the exponential growth phase of the bacteria immediately following infection that peaks on day 4, and is followed by the biofilm growth phase at a significantly lower metabolic rate (p,<,0.05). Collectively, these studies demonstrate the first quantitative model of implant-associated OM that defines the kinetics of microbial growth, osteolysis, and humoral immunity following infection. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J. Orthop Res 26:96,105, 2008 [source] Identification of an ospC operator critical for immune evasion of Borrelia burgdorferiMOLECULAR MICROBIOLOGY, Issue 1 2007Qilong Xu Summary Timely expression of the outer surface protein C (OspC) is crucial for the pathogenic strategy of the Lyme disease spirochete Borrelia burgdorferi. The pathogen abundantly expresses OspC during initial infection when the antigen is required, but downregulates when its presence poses a threat to the spirochetes once the anti-OspC humoral response has developed. Here, we show that a large palindromic sequence immediately upstream of the ospC promoter is essential for the repression of ospC expression during murine infection and for the ability of B. burgdorferi to evade specific OspC humoral immunity. Deletion of the sequence completely diminished the ability of B. burgdorferi to avoid clearance by transferred OspC antibody in SCID mice. B. burgdorferi lacking the regulatory element was able to initiate infection but unable to persist in immunocompetent mice. Taken together, the regulatory element immediately upstream of the ospC promoter serves as an operator that may interact with an unidentified repressor(s) to negatively regulate ospC expression and is essential for the immune evasion of B. burgdorferi. [source] Detection of the Sm31 antigen in sera of Schistosoma mansoni, infected patients from a low endemic areaPARASITE IMMUNOLOGY, Issue 1 2010G. S. SULBARÁN Summary Schistosoma mansoni cathepsin B (Sm31) is a major antigen from adult worms that circulates in the blood of infected patients (Li et al., Parasitol Res 1996; 82: 14,18). An analysis of the Sm31 sequence (Klinkert et al., Mol Biochem Parasitol 1989; 33: 113,122) allowed the prediction of seven hydrophilic regions that were confirmed to be exposed on the surface of a 3D model of Sm31; the species specificity of these regions was checked using BLAST analysis. The corresponding peptides were chemically synthesized in polymerazible forms using the t-Boc technique. Rabbits developed a high humoral response against these peptides as tested by a multiple antigen blot assay; it recognized native Sm31 in crude S. mansoni extracts and as circulating antigen in sera of S. mansoni-infected patients by western blot. Relevant antigenic determinants were located at the N- and C-terminus sequences. Antibodies against these regions recognized the native enzyme in an ELISA-like assay called cysteine protease immuno assay in which the immunocaptured enzyme was revealed by the intrinsic cathepsin B hydrolytic activity of Sm31. The method successfully and specifically detected Sm31 in sera of infected individuals, most of them (83·3%) with light infections, offering a rationale for the development of parasite enzyme capture assays using anti-synthetic peptide antibodies for possible use in the diagnosis of schistoso,iasis. [source] CD40-expressing plasmid induces anti-CD40 antibody and enhances immune responses to DNA vaccinationTHE JOURNAL OF GENE MEDICINE, Issue 1 2010Hanqian Xu Abstract Background Various approaches have been used to improve the efficacy of DNA vaccination, including the incorporation of molecular adjuvants. Because the CD40 ligand,CD40 interaction plays a major role in initiating immune responses, we sought to develop a molecular adjuvant targeting this interaction. Methods and Results We immunized mice with a foot-and-mouth disease virus DNA vaccine, pcD-VP1, together with a CD40-expressing plasmid, pcD-CD40. We found that pcD-CD40 induced anti-CD40 antibodies, which temporally correlated with the augmented production of anti-VP1 antibody. pcD-CD40 similarly augmented the humoral response of another DNA vaccine that targets hepatitis B virus, and passive transfer of anti-CD40 antisera also showed a similar effect. Furthermore, the pcD-CD40-elicited anti-CD40 antibodies were able to activate the CD40 signal pathway in antigen-presenting cells in vitro, which led to the maturation of dendritic cells (DCs) and DC-mediated T cell activation. Thus, pcD-CD40 augments DNA vaccination by inducing anti-CD40 antibodies, which in turn promotes T cell activation. Conclusions This is the first reported ,proadjuvant' that augments DNA vaccination indirectly by eliciting agonistic antibodies. Copyright © 2009 John Wiley & Sons, Ltd. [source] Complex nature of the human antisperm antibody response in SCID miceANDROLOGIA, Issue 2 2004M. Kurpisz Summary. Human peripheral blood mononuclear (PBMs) cells were introduced into the peritoneal cavity of severely-combined immunodeficient (SCID) mice in concentrations of 2.5,4.0 × 107 cells per mouse. Whole mononuclear cell suspensions were used either unstimulated or following primary in vitro culture with human spermatozoa. In some experiments, immunodepletion of CD8+ cells was carried out prior to grafting. Lymphocytes were obtained from nonsensitized (to antigen) human subjects or from individuals who were primed in vivo (vasectomized individuals in case of sperm antigens). An enzyme-linked immunosorbent assay was employed to assess total human immunoglobulin (G or M) levels as well as the specificity of the antibodies generated. We have been successful by generating primary and secondary immune responses with ,naďve' human lymphocytes, challenged with chlamydia or ovalbumin but without adjuvant or CD8+ immunodepletion; however, we were unable to induce specific antibodies to spermatozoa under this regime in SCID male mice. We then employed female SCID mice, treated with sperm antigen extracts (glycosylated or deglycosylated) encapsulated in liposomes and human lymphocytes obtained from ,naďve' or pre-sensitized in vivo subjects. It was found that the most pronounced humoral response to sperm antigens was obtained with deglycosylated antigens and PBMs from vasectomized (in vivo pre-primed to spermatozoa) individuals. A presented SCID mice model can be helpful at understanding of antisperm antibody development and the molecular nature of generated antibodies to modified sperm antigenic entities. [source] Antibodies produced by clonally expanded plasma cells in multiple sclerosis cerebrospinal fluid,ANNALS OF NEUROLOGY, Issue 6 2009Gregory P. Owens PhD Objective Intrathecal IgG synthesis, persistence of bands of oligoclonal IgG, and memory B-cell clonal expansion are well-characterized features of the humoral response in multiple sclerosis (MS). Nevertheless, the target antigen of this response remains enigmatic. Methods We produced 53 different human IgG1 monoclonal recombinant antibodies (rAbs) by coexpressing paired heavy- and light-chain variable region sequences of 51 plasma cell clones and 2 B-lymphocyte clones from MS cerebrospinal fluid in human tissue culture cells. Chimeric control rAbs were generated from anti-myelin hybridomas in which murine variable region sequences were fused to human constant region sequences. Purified rAbs were exhaustively assayed for reactivity against myelin basic protein, proteolipid protein, and myelin oligodendrocyte glycoprotein by immunostaining of transfected cells expressing individual myelin proteins, by protein immunoblotting, and by immunostaining of human brain tissue sections. Results Whereas humanized control rAbs derived from anti-myelin hybridomas and anti-myelin monoclonal antibodies readily detected myelin antigens in multiple immunoassays, none of the rAbs derived from MS cerebrospinal fluid displayed immunoreactivity to the three myelin antigens tested. Immunocytochemical analysis of tissue sections from MS and control brain demonstrated only weak staining with a few rAbs against nuclei or cytoplasmic granules in neurons, glia, and inflammatory cells. Interpretation The oligoclonal B-cell response in MS cerebrospinal fluid is not targeted to the well-characterized myelin antigens myelin basic protein, proteolipid protein, or myelin oligodendrocyte glycoprotein. Ann Neurol 2009;65:639,649 [source] Immune response of DNA vaccine against lymphocystis disease virus and expression analysis of immune-related genes after vaccinationAQUACULTURE RESEARCH, Issue 10 2010Feng Rong Zheng Abstract In this study, we found that an intramuscular injection of Japanese flounder (Paralichthys olivaceus, 60,80 g in weight and 15,20 mL in length) with 5 ,g of a DNA vaccine (pEGFP-N2-LCDV-cn-MCP 0.6 kb, containing lymphocystis disease virus major capsid protein gene) induced a strong immune response. Subsequent real-time polymerase chain reaction showed that the expression of immune-related genes [e.g., major histocompatibility complex (MHC) class I ,, MHC II ,, T-cell receptor (TCR), tumour necrosis factor (TNF), tumour necrosis factor receptor (TNFR), Mx, interleukin (IL)-1,, CXC and IL-8R] was significantly changed after DNA vaccination. The most remarkable alternation was the expression of MHC I , and MHC II , genes: MHC II , reached the maximum on day 8 in different tissues, and MHC I , on day 2 in the intestine and gills. The expression of TCR increased and reached a plateau in 2 days in the spleen, gills, kidney and liver after vaccination and then decreased after day 8. In contrast, the expression of TCR in the intestine increased and reached a plateau in 8 days. The expression of IL-8R reached the maximum on day 2 in different tissues and then decreased on day 8. Mx increased in the gills, kidney, spleen and liver on days 2, 8, 2 and 2, but decreased in the intestine, gills, spleen and liver on days 2, 8, 8 and 8 respectively. The TNFR expression increased in the spleen, kidney and gills on days 2, 8 and 8, but decreased in intestine, liver and gills on days 2, 8 and 8 respectively. The expression of TNF, CXC and IL-1, increased 2 and 8 days after the injection of DNA vaccine. However, the expression of TNF, CXC and IL-1, altered on days 2 and 8 with different patterns in different tissues respectively. The fish responded to the DNA vaccine by yielding a specific immunoglobulin against lymphocystis disease virus (LCDV) as observed with indirect ELISA. The DNA vaccine induced a unique humoral response, suggesting that the DNA vaccine activated both cellular and humoral defences of the specific immune system of Japanese flounder. [source] Effects of anti-CD154 treatment on B cells in murine systemic lupus erythematosusARTHRITIS & RHEUMATISM, Issue 2 2003Xiaobo Wang Objective To determine the immunologic effects of anti-CD154 (CD40L) therapy in the (NZB × NZW)F1 mouse model of systemic lupus erythematosus. Methods Twenty-week-old and 26-week-old (NZB × NZW)F1 mice were treated with continuous anti-CD154 therapy. Mice were followed up clinically, and their spleens were studied at intervals for B and T cell numbers and subsets and frequency of anti,double-stranded DNA (anti-dsDNA),producing B cells. T cell,dependent immunity was assessed by studying the humoral response to the hapten oxazolone. Results IgG anti-dsDNA antibodies decreased during therapy and disease onset was delayed, but immune tolerance did not occur. During treatment, there was marked depletion of CD19+ cells in the spleen; however, autoreactive IgM-producing B cells could still be detected by enzyme-linked immunospot assay. In contrast, few IgG- and IgG anti-dsDNA,secreting B cells were detected. Eight weeks after treatment cessation, the frequency of B cells producing IgG anti-dsDNA antibodies was still decreased in 50% of the mice, and activation and transition of T cells from the naive to the memory compartment were blocked. Anti-CD154 treatment blocked both class switching and somatic mutation and induced a variable period of relative unresponsiveness of IgG anti-dsDNA,producing B cells, as shown by decreased expression of the CD69 marker and failure to generate spontaneous IgG anti-dsDNA,producing hybridomas. Treated mice mounted an attenuated IgM response to the hapten oxazolone and produced no IgG antioxazolone antibodies. Conclusion Anti-CD154 is a B cell,depleting therapy that affects multiple B cell subsets. Activation of both B and T cells is prevented during therapy. After treatment cessation, autoreactive B cells progress through a series of activation steps before they become fully competent antibody-producing cells. The general immunosuppression induced during treatment will need to be taken into account when using B cell,depleting regimens in humans. [source] Seroreactivity against MAGE-A and LAGE-1 proteins in melanoma patientsBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2003D. Usener Summary Background Cancer-testis antigens exemplify a growing number of tumour antigens which are expressed in a variety of malignancies, but not in normal tissues other than germ cells, primarily those of the testis. Objectives To investigate the humoral response to known cancer-testis antigens in melanoma patients. Methods We used phage clones coding for seven different melanoma antigens MAGE-A or LAGE-1A proteins. These clones were isolated using the newly developed DNA hybridization analysis of recombinantly expressed cDNA libraries (HYREX) approach. HYREX combines the advantage of a nonradioactive library screening method with the possibility of subsequently analysing the serological response to the recombinant proteins. We isolated clones coding for MAGE-A1, -A3, -A4b, -A6, -A9 and -A12, as well as LAGE-1A. Additionally, we correlated gene expression and seroreactivity. Results Between 13% and 27% of sera (n = 15) were reactive against individual tumour antigens. We found the presence of specific antibodies was, with only two exceptions, generally correlated with mRNA expression of the antigen within cell lines derived from the same patient. While cross-reactivity of patients' IgG might play a role in these cases, antibodies from patients' sera were able to distinguish even the closely related MAGE-A3 and -A6. In general, the mRNA expression frequency was higher than the detected IgG responses. Conclusions Antibody recognition of specific tumour antigens by patients' sera may be used for evaluating the possible immunogenicity of new antigens; serological tests could be used for tumour monitoring purposes. [source] Identification of a prostate-specific membrane antigen-derived peptide capable of eliciting both cellular and humoral immune responses in HLA-A24+ prostate cancer patientsCANCER SCIENCE, Issue 7 2003Kazuhiko Kobayashi We tried to identify prostate-specific membrane antigen (PSMA)-derived peptides capable of eliciting both cellular and humoral immune responses in peripheral blood mononuclear cells (PBMCs) and plasma of HLA-A24+ prostate cancer patients, respectively. For cellular response, peptide-specific and prostate cancer-reactive responses of in vitro -stimulated PBMCs were examined with regard to interferon (IFN)-, production and cytotoxicity against both a parental HLA-A24, prostate cancer cell line (PC-93) and an HLA-A24-expressing transfectant cell line (PC93-A24). For humoral response, patients' plasma was tested for reactivity to the peptides by means of an enzyme-linked immunosorbent assay (ELISA). Among 13 PSMA peptides, PSMA 624,632 peptide induced peptide-specific and tumor-reactive cytotoxic T lymphocytes (CTLs) most effectively. The PSMA 624,632 peptide-stimulated PBMCs from either healthy donors or prostate cancer patients produced a significant level of IFN-, in response to prostate cancer cells in an HLA-A24-restricted manner, and also showed a higher level of cytotoxicity against PC93-A24 than against PC93. Antibodies to the PSMA 624,632 peptide, but not to any others, were detected in prostate cancer patients. These results demonstrate that the PSMA 624,632 peptide could be an appropriate molecule for use in specific immunotherapy of HLA-A24+ patients with prostate cancer. [source] Leishmania cell surface prohibitin: role in host,parasite interactionCELLULAR MICROBIOLOGY, Issue 4 2010Rohit Jain Summary Proteins selectively upregulated in infective parasitic forms could be critical for disease pathogenesis. A mammalian prohibitin orthologue is upregulated in infective metacyclic promastigotes of Leishmania donovani, a parasite that causes visceral leishmaniasis. Leishmania donovani prohibitin shares 41% similarity with mammalian prohibitin and 95,100% within the genus. Prohibitin is concentrated at the surface of the flagellar and the aflagellar pole, the aflagellar pole being a region through which host,parasite interactions occur. Prohibitin is attached to the membrane through a GPI anchor. Overexpression of wild-type prohibitin increases protein surface density resulting in parasites with higher infectivity. However, parasites overexpressing a mutant prohibitin with an amino acid substitution at the GPI anchor site to prevent surface expression through GPI-link show lesser surface expression and lower infective abilities. Furthermore, the presence of anti-prohibitin antibodies during macrophage,Leishmania interaction in vitro reduces infection. The cognate binding partner for Leishmania prohibitin on the host cell appears to be macrophage surface HSP70, siRNA mediated downregulation of which abrogates the capability of the macrophage to bind to parasites. Leishmania prohibitin is able to generate a strong humoral response in visceral leishmaniasis patients. The above observations suggest that prohibitin plays an important role in events leading to Leishmania,host interaction. [source] How to kill a mocking bug?CELLULAR MICROBIOLOGY, Issue 4 2006Vitor B. Pinheiro Summary All metazoans have evolved means to protect themselves from threats present in the environment: injuries, viruses, fungi, bacteria and other parasites. Insect protection includes innate physical barriers and both cellular and humoral responses. The insect innate immune response, best characterized in Drosophila melanogaster, is a rapid broad response, triggered by pathogen-associated molecular patterns (PAMPs) recognition, which produces a limited range of effectors that does not alter upon continued pathogen exposure and lacks immunological memory. The Drosophila response, particularly its humoral response, has been investigated by both low and high-throughput methods. Three signalling pathways conserved between insects and mammals have been implicated in this response: Toll (equivalent to mammalian TLR), Imd (equivalent to TNF,) and Hop (equivalent to JAK/STAT). This review provides an entry point to the insect immune system literature outlining the main themes in D. melanogaster bacterial pathogen detection and humoral and cellular immune responses. The Drosophila immune response is compared with other insects and the mammalian immune system. [source] CD4+CD25+ regulatory T,cells control the magnitude ofT-dependent humoral immune responses to exogenous antigensEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 4 2006Fouad Eddahri Abstract CD4+CD25+ T,reg cells are critical for peripheral tolerance and prevention of autoimmunity. Here we show that CD4+CD25+ T,reg also regulate the magnitude of humoral responses against a panel of T-dependent antigens of foreign origin during both primary and secondary immune responses. Depletion of CD4+CD25+ T,cells leads to increased antigen-specific antibody production and affinity maturation but does not affect T-independent B,cell responses, suggesting that CD4+CD25+ T,reg exert a feedback mechanism on non-self antigen-specific antibody secretion by dampening the T,cell help for B,cell activation. Moreover, we show that CD4+CD25+ T,reg also suppress in vitro B,cell immunoglobulin production by inhibiting CD4+CD25, T,cell help delivery, and that blockade of TGF-, activity abolishes this suppression. [source] Depletion of immature B,cells during Trypanosoma cruzi infection: involvement of myeloid cells and the cyclooxygenase pathwayEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 6 2005Elina Zuniga Abstract The ability of a microorganism to elicit or evade B,cell responses represents a determinant factor for the final outcome of an infection. Although pathogens may subvert humoral responses at different stages of B,cell development, most studies addressing the impact of an infection on the B,cell compartment have focused on mature B,cells within peripheral lymphoid organs. Herein, we report that a protozoan infection, i.e. a Trypanosoma cruzi infection, induces a marked loss of immature B,cells in the BM, which also compromises recently emigrated B,cells in the periphery. The depletion of BM immature B,cells is associated with an increased rate of apoptosis mediated by a parasite-indirect mechanism in a Fas/FasL-independent fashion. Finally, we demonstrated that myeloid cells play an important role in B,cell depletion, since CD11b+ BM cells from infected mice secrete a product of the cyclooxygenase pathway that eliminates immature B,cells. These results highlight a previously unrecognized maneuver used by a protozoan parasite to disable B,cell generation, limiting host defense and favoring its chronic establishment. [source] Enhancement of protective humoral immune responses against Herpes simplex virus-2 in DNA-immunized guinea-pigs using protein boostingFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2008Fatemeh Fotouhi Abstract Genital Herpes is a common sexually transmitted disease that is caused mostly by Herpes simplex virus type 2 (HSV-2). Its prevalence has increased in developing countries in spite of the availability of valuable antiviral drug therapy. Considering the importance of HSV-2 infections, effective vaccines remain the most likely hope for controlling the spread of HSV diseases. In the present study, the complete HSV-2 glycoprotein D gene was isolated and cloned into different plasmid vectors to construct a DNA vaccine and prepare recombinant subunit vaccines using a baculovirus expression system. The vaccines were tested alone or in combination to evaluate their ability to induce protective immunity in guinea-pigs against genital HSV infections. Immunization elicited humoral responses as measured by neutralization tests and enzyme-linked immunosorbent assay, and immunized animals had less severe genital skin disease as well as reduced replication of the challenging virus in the genital tract during experimental infection. Our results further demonstrate that DNA priming-protein boosting induced a neutralizing antibody titer higher than that obtained with DNA,DNA vaccination. The massive increase of antibody titer following DNA priming-protein boosting might be attributed to a recall of B cell memory. [source] Immunogenicity of synthetic saccharide fragments of Vibrio cholerae O1 (Ogawa and Inaba) bound to Exotoxin AFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2006Terri K. Wade Abstract Recombinant exotoxin A (rEPA) from Pseudomonas aeruginosa conjugated to Vibrio cholerae O1 serotype-specific polysaccharides (mono-, di- and hexasaccharide) were immunogenic in mice. Monosaccharide conjugates boosted the humoral responses to the hexasaccharide conjugates. Prior exposure to purified Ogawa lipopolysaccharide (LPS) enabled contra -serotype hexasaccharide conjugates to boost the vibriocidal response, but Inaba LPS did not prime for an enhanced vibriocidal response by a contra -serotype conjugate. Prior exposure to the carrier, and priming B cells with the LPS of either serotype, resulted in enhanced vibriocidal titers if the Ogawa hexasaccharides were used, but a diminished response to the Inaba LPS. These studies demonstrate that the ,functional' B cell epitopes on the LPS differ from those of the neoglycoconjugates and that the order of immunization and the serotype of the boosting conjugate can influence the epitope specificity and function of the antisera. [source] | |||||||||||||||||||||||||||||||||||||