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IgG Responses (igg + response)
Selected AbstractsORIGINAL ARTICLE: Estradiol Limits Viral Replication Following Intravaginal Immunization Leading to Diminished Mucosal IgG Response and Non-sterile Protection Against Genital Herpes ChallengeAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2010Amy Gillgrass Citation Gillgrass A, Chege D, Bhavanam S, Kaushic C. Estradiol limits viral replication following intravaginal immunization leading to diminished mucosal IgG response and non-sterile protection against genital herpes challenge. Am J Reprod Immunol 2010; 63: 299,309 Problem, Previously we reported that ovariectomized (OVX) mice receiving estradiol (E) prior to immunization with an attenuated strain of HSV-2 (TK-HSV-2) were not protected. Lack of protection in the E group was because of the inability of TK-HSV-2 to penetrate the thick keratinized epithelium. In this study, we determined the outcome of immunization after the thickening of vaginal epithelium following E-treatment waned. OVX, C57BL/6 mice were given Progesterone (P), E or saline (S) for 3 days and immunized with IVAG TK-HSV-2. Method of study, To determine the time point at which E-treated mice could be successfully immunized, the mice were inoculated with TK-HSV-2 between days 1 and 7 (ED1,ED7) post-E-treatment and challenged with IVAG HSV-2 three weeks later. Results, The level of infection post-immunization correlated with HSV-2-specific IgG antibody level, which correlated with sterile protection. No viral infection was observed in ED1,ED3 groups and no specific antibodies were detected, resulting in no protection. Moderate infection was seen in ED5 group, resulting in low antibody production and non-sterile protection in 87.5% of mice. High antibody titers and sterile protection were observed in all groups that experienced robust infection post-immunization. Conclusion, The results show that estradiol leads to limited viral replication and diminished mucosal IgG response, resulting in non-sterile immune protection against genital herpes infection. [source] Marginal zone B cell enrichment and strong follicular B cell reduction correlate with a delayed IgG response in a light chain diversity restricted mouse modelEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 10 2004Yacine Abstract Recently developed B6.,,,SEG mice (by crossing ,, and C57BL/6 mice congenic for the wild Mus spretus SEG strain , locus lacking genes coding for ,1 and ,3) have a very reduced light chain diversity. B6.,,,SEG mice produce only ,2 and ,x light chains. Regardless of their Igh haplotype, B6.,,,SEG mice show a restricted B cell distribution by light chain subtype with ,x dominance in all peripheral compartments except peritoneal cavity where ,2 is dominant. This distribution suggests that selection mechanisms act differently in different B cell compartments on ,2 and ,x bearing B cells. Sequence analysis before or following immunization did not reveal unusual mechanisms of diversification. B6.,,,SEG mice still respond to various challenging antigens using new Ab patterns. In particular, regardless of Igha or Ighb haplotypes, the anti-2,4-dinitrophenyl response is characterized by a restricted diversity for both heavy and light chains and a delayed IgG response when compared to B6 and B6.,, mice. We suggest that the delayed IgG response is due to the expansion of marginal zone B cells whereas follicular B cells are strongly reduced. [source] The effect of immunization on the response to P. gingivalis infection in mice is adjuvant-dependentJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2005Yael Houri-Haddad Abstract Aim: Studies on vaccines against the periodontal pathogen Porphyromonas gingivalis have produced conflicting results, but no consideration has been given to the role of different adjuvants in these vaccines. We have previously shown that an intra-chamber challenge with heat-killed P. gingivalis was modified by immunization with different adjuvants. This study tested the hypothesis that different adjuvants in P. gingivalis vaccines would differentially modify the host response to a live P. gingivalis infection. Results: Using P. gingivalis -infected subcutaneous chambers in mice, we show that vaccination with P. gingivalis in alum attenuated the pro-inflammatory cytokine levels at the site of infection, while the vaccine containing incomplete Freund's adjuvant did the opposite. Although both vaccines induced a similar humoral IgG response, P. gingivalis -induced abscesses were significantly smaller in the alum-adjuvant group. Conclusions: The results suggest that the immune response and the resultant protection to a P. gingivalis infection, in P. gingivalis -vaccinated mice, are adjuvant-dependent. [source] Serological response to hepatitis E virus genotype 3 infection: IgG quantitation, avidity, and IgM responseJOURNAL OF MEDICAL VIROLOGY, Issue 1 2008R. Bendall Abstract Sequential sera were collected from 18 acute cases of UK-acquired hepatitis E. The virus strains in all cases were of genotype 3. The IgM and IgG response to acute infection were documented over time using EIA kits based on a peptide antigen, pE2, which is derived from a genotype 1 strain of hepatitis E virus (HEV). Ninety-five percentage of acute sera were IgM positive; after 6 months or more only 12% remained positive. The kit was adapted to quantify the IgG response (in WHO U/ml) and to determine antibody avidity. Following acute infection, anti-HEV IgG concentrations rose between 6.9- and 90-fold. IgG avidity was low (<25%) in most acute sera. After 6 months IgG avidity was greater than 50% in all cases. One patient with a poor IgM response and high avidity antibody in acute sera may have had a second HEV infection. Taken together, these results confirm that the pE2-based EIA kits are suitable for diagnosing acute HEV genotype 3 infection. With simple modifications the IgG kit can measure anti-HEV concentration and avidity, which can be used to confirm acute infection. J. Med. Virol. 80:95,101, 2008. © 2007 Wiley-Liss, Inc. [source] Lower antibody response to Porphyromonas gingivalis associated with immunoglobulin G Fc, receptor IIB polymorphismJOURNAL OF PERIODONTAL RESEARCH, Issue 6 2008Y. Honma Background and Objective:, Human Fc,RIIB is one of the receptors for immunoglobulin G (IgG) and suppresses the activation of B lymphocytes through cross-linking with the B cell receptor via immune complexes. This function of Fc,RIIB is essential for the negative regulation of antibody production. Our previous study has demonstrated the gene polymorphism Fc,RIIB-I232T to be associated with periodontitis. The polymorphism Fc,RIIB-232T has been reported to inhibit B-cell antigen receptor signaling more effectively compared to Fc,RIIB-232I, while other groups concluded that Fc,RIIB-232T had no ability to inhibit activatory receptors. In this study, we examined whether Fc,RIIB-I232T polymorphism would change the IgG antibody response to the periodontopathic bacteria Porphyromonas gingivalis. Material and Methods:, Forty-seven patients with periodontitis were genotyped with the direct sequencing of genome DNA. Serum IgG and specific IgG subclass levels for the sonicate of P. gingivalis and the recombinant 40 kDa outer membrane protein (OMP) were determined. Results:, No significant difference in the total IgG level and IgG response to P. gingivalis sonicate were observed between sera from Fc,RIIB-232T carriers and non-carriers. The Fc,RIIB-232T carriers revealed a significantly lower IgG2 response to P. gingivalis 40 kDa OMP compared to non-carriers (p = 0.04, Mann,Whitney U -test). Lower responses of Fc,RIIB-232T carriers were also observed in specific IgG and IgG1 levels. The Fc,RIIB-232T carriers revealed a low level of IgG2 response to P. gingivalis 40 kDa OMP, even with a high average probing pocket depth. Conclusion:, These results suggest that association of the Fc,RIIB-232T allele with periodontitis might be related to the lower levels of antibody response to P. gingivalis. [source] Allergen IgE-isotype-specific suppression by maternally derived monoclonal anti-IgG-idiotypeALLERGY, Issue 1 2010R. I. Tanasa Abstract Background:, The dramatic increase of IgE-mediated allergic diseases in western countries demonstrates the urgent need for new therapeutic or prophylactic approaches. In mice, a prophylactic long-lasting allergen-specific suppression of IgE responsiveness is induced by maternal IgG antibodies to allergens like ovalbumin, phospholipase A2 (bvPLA2) or ovomucoid. As neonatal application or maternally derived pathogen-reactive antibodies (idiotypes) as well as corresponding anti-idiotypes can induce anti-microbial protection, we probed the transgenerational IgE-suppressive mechanism with a syngeneic monoclonal anti-idiotypic antibody. Methods:, The monoclonal bee-venom-phospholipase A2 (bvPLA2)-reactive IgG antibody MS613 (idiotype) or the corresponding syngeneic anti-idiotype II/2-19 were injected during the first 2 days postpartum to the dams. Immunization of offspring with minute doses of IgE-inducing bvPLA2 was started at an adult age of 3˝ months. Results:, The postnatal transfer of the anti-bvPLA2 idiotype MS613 or the corresponding anti-idiotype II/2-19 induced long-lasting allergen-specific IgE suppression in a dose-dependent manner, while the IgG response to the allergen developed normally. Quantitatively, the anti-idiotype was more effective than idiotype. Molecular modeling of the idiotype-anti-idiotype complex and its comparison with the bvPLA2 structure revealed that the anti-idiotype does not mimic bvPLA2 epitopes and thus can not be regarded as an internal image antibody and, consequently, does not function as a surrogate antigen. Conclusions:, Idiotypic network reactivity is at least one major factor for induction of transgenerational IgE suppression by maternal IgG antibodies. If applicable to humans, these data suggest the possibility of a prophylactic and possibly therapeutic treatment of IgE-mediated allergic diseases with anti-idiotypic antibodies. [source] Humoral immune responses during a malaria vaccine trial in Tanzanian infantsPARASITE IMMUNOLOGY, Issue 9 2000Galindo The development of a malaria vaccine is a priority for improved and sustained malaria control. Optimal use of a vaccine in Africa will only be achieved if it can be delivered through the Expanded Programme of Immunization (EPI). We have completed a trial of the peptide vaccine SPf66 in Tanzanian infants, given alongside the EPI vaccines. This paper describes the humoral responses to SPf66 and the EPI vaccines. A total of 1207 infants were recruited into a two-arm, double-blind, individually randomized placebo-controlled trial of SPf66. The objectives of the trial were to determine the safety, immunogenicity and efficacy of SPf66 and to assess interactions with EPI vaccines when three doses of SPf66 were delivered alongside the EPI vaccines. Cross-sectional surveys were carried out to asses seroconversion rates to the EPI vaccines and the antibody response to SPf66 (NANP)50 and Plasmodium falciparum lysates. Seroconversion rates to EPI vaccines were high and no statistically significant differences in prevalence or titres were found between SPf66 and placebo recipients. IgG antibodies against SPf66 (NANP)50 and whole P. falciparum lysate were present in high titres in mothers of recruited children at the time of birth. Vaccination with SPf66 stimulated a good anti-SPf66 IgG response which declined to preimmunization levels by 2 years of age and which was not associated with protection against clinical malaria. The vaccine induced no IgG antibodies against (NANP)50 or P. falciparum lysates. SPf66 stimulated a humoral immune response when given to very young infants and did not interfere with seroconversion to EPI vaccines. The response to SPf66 was qualitatively different from that seen in older children, in whom SPf66 has been shown to be moderately efficacious. This difference raises concerns about the difficulties of immunizing very young infants who need to be targeted by antimalarial vaccination programs. [source] ORIGINAL ARTICLE: Estradiol Limits Viral Replication Following Intravaginal Immunization Leading to Diminished Mucosal IgG Response and Non-sterile Protection Against Genital Herpes ChallengeAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 4 2010Amy Gillgrass Citation Gillgrass A, Chege D, Bhavanam S, Kaushic C. Estradiol limits viral replication following intravaginal immunization leading to diminished mucosal IgG response and non-sterile protection against genital herpes challenge. Am J Reprod Immunol 2010; 63: 299,309 Problem, Previously we reported that ovariectomized (OVX) mice receiving estradiol (E) prior to immunization with an attenuated strain of HSV-2 (TK-HSV-2) were not protected. Lack of protection in the E group was because of the inability of TK-HSV-2 to penetrate the thick keratinized epithelium. In this study, we determined the outcome of immunization after the thickening of vaginal epithelium following E-treatment waned. OVX, C57BL/6 mice were given Progesterone (P), E or saline (S) for 3 days and immunized with IVAG TK-HSV-2. Method of study, To determine the time point at which E-treated mice could be successfully immunized, the mice were inoculated with TK-HSV-2 between days 1 and 7 (ED1,ED7) post-E-treatment and challenged with IVAG HSV-2 three weeks later. Results, The level of infection post-immunization correlated with HSV-2-specific IgG antibody level, which correlated with sterile protection. No viral infection was observed in ED1,ED3 groups and no specific antibodies were detected, resulting in no protection. Moderate infection was seen in ED5 group, resulting in low antibody production and non-sterile protection in 87.5% of mice. High antibody titers and sterile protection were observed in all groups that experienced robust infection post-immunization. Conclusion, The results show that estradiol leads to limited viral replication and diminished mucosal IgG response, resulting in non-sterile immune protection against genital herpes infection. [source] ORIGINAL ARTICLE: In Vitro and In Vivo Studies Evaluating Recombinant Plasmid pCXN2-mIzumo as a Potential Immunocontraceptive AntigenAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 3 2009Gang An Problems, Study on feasibility of pCXN2-mIzumo as a potential immunocontraceptive antigen. Method of study, Two groups of mice received 100 ,g/mouse plasmids of pCXN2-mIzumo and pCXN2 respectively. RT-PCR Immunofluorescence assay and ELISA were performed to observe pCXN2-mIzumo expression and antibody response in the inoculated mice. Sperm penetration assay and animal mating were employed to detect differences of in vitro fertilization (IVF) rate and mean litter size between the experimental and control groups. Results, Izumo cDNA positive bands were detected in sample from mice immunized with pCXN2-mIzumo. IgG response started to rise at 2 weeks after first boost and reached the highest antibody titers at 2 weeks after third boost of immunization with pCXN2-mIzumo in the experimental mice. In vitro fertilization rate in the experimental group (11.57%) was significantly lower than that in control (36.60%). Significant difference of mean litter size between female experimental and control groups was observed, and there was significant negative correlation between individual anti-serum titers and litter size (r = ,0.308, P < 0.05). Conclusion, pCXN2-mIzumo plasmid possesses appreciable anti-fertility potential. [source] Measuring T cell immunity to influenza vaccination in children after haemopoietic stem cell transplantationBRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2004W. Nicholas Haining Summary Quantitative assessment of immunogen-specific T cell responses may provide a meaningful surrogate marker of functional immunity in patients following haemopoietic stem cell transplantation (HSCT). We developed a flow-cytometric assay to quantify antigen-specific T cell immunity to influenza-A and studied the T cell response to influenza vaccination in five children, 3,21 months post-HSCT. All patients showed an increase in influenza-A-specific CD4+ immunity following vaccination while none had a detectable IgG response to the vaccine. This assay proved sufficiently sensitive to evaluate changes in T cell memory in immunocompromised individuals and could be used to better characterize post-HSCT immune reconstitution. [source] Oral tolerance induction to Dermatophagoides pteronyssinus and Blomia tropicalis in sensitized mice: occurrence of natural autoantibodies to immunoglobulin ECLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2002M. N. Sato Summary Background The dust mites Dermatophagoides pteronyssinus (Dp) and Blomia tropicalis (Bt) are important sources of indoor allergens in tropical and subtropical countries. Murine models allow the analysis of the immune response and regulation of IgE production to Dp and Bt allergens. Oral tolerance induces unresponsiveness in naive animals, but its application in sensitized animals can provide useful information to improve allergy therapy. Objective To study the profile of IgE and IgG subclasses antibody upon oral administration with Bt and Dp extract in previously sensitized mice. Further, the occurrence of autoantibodies IgG anti-IgE in the immunization and in the oral tolerance was investigated. Methods A/Sn mice were immunized with Bt or Dp extract in alum, orally administrated with 0.25 mg of Bt or Dp extract or PBS at the 6th, 7th and 8th days after immunization and boosted twice with their respective allergens. To analyse the mice groups, specific IgE antibodies were measured by passive anaphylaxis reaction and specific IgG subclasses and anti-IgE IgG autoantibody by ELISA assay. Results IgE levels were markedly increased in Bt-immunized mice compared with Dp-immunized mice. A distinct profile of the specific isotypes was verified in Bt-immunized mice with a preferential production of IgG3 and IgA antibodies, whereas Dp-immunized mice developed high titres of anti-Dp IgG1, IgG2a and IgG2b antibodies. The antigen feeding inhibited IgE response in both fed-mice groups but only Dp-fed mice presented decreased levels of IgG antibodies. Free anti-IgE IgG autoantibodies were detected mainly in the Dp-immunization and they correlated with the antibody isotypes found against the allergen. Conclusions This is the first time that the murine-type I hypersensitivity is employed to study Bt-immunization, showing a marked IgE production, associated with IgG response, which is at least in part driven by T-independent antigens. The oral tolerance protocol in previously sensitized animals was able to down-modulate IgE response and points out this route as a strategy for allergy therapy. [source] Safety and preliminary immunogenicity of MenC/P64k, a meningococcal serogroup C conjugate vaccine with a new recombinant carrierFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 3 2006Antonio E. Pérez Abstract This study reports the preliminary assessment of the safety and immunogenicity of the first serogroup C conjugate vaccine candidate that includes meningococcal P64k recombinant protein as the carrier (MenC/P64k). Twenty volunteers were recruited for a double-blind, randomized, controlled phase I clinical trial, receiving a single dose of MenC/P64k (study group) and a single dose of the commercial polysaccharide vaccine AC (control group). Only mild reactions were observed. No statistical differences were detected between the antipolysaccharide C IgG responses of both groups as well as between bactericidal serum titre (P>0.05). The MenC/P64k vaccine was found to have a good safety profile, to be well tolerated and immunogenic. [source] Bordetella pertussis fimbriae are effective carrier proteins in Neisseria meningitidis serogroup C conjugate vaccinesFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 2 2001Karen M Reddin Abstract Serogroup C meningococcal conjugate vaccines generally use diphtheria or tetanus toxoids as the protein carriers. The use of alternative carrier proteins may allow multivalent conjugate vaccines to be formulated into a single injection and circumvent potential problems of immune suppression in primed individuals. Bordetella pertussis fimbriae were assessed as carrier proteins for Neisseria meningitidis serogroup C polysaccharide. Fimbriae were conjugated to the polysaccharide using modifications of published methods and characterised by size exclusion chromatography; co-elution of protein and polysaccharide moieties confirmed conjugation. The conjugates elicited boostable IgG responses to fimbriae and serogroup C polysaccharide in mice, and IgG:IgM ratios indicated that the responses were thymus-dependent. High bactericidal antibody titres against a serogroup C strain of N. meningitidis were also observed. In a mouse infection model, the conjugate vaccine protected against lethal infection with N. meningitidis. Therefore, B. pertussis fimbriae are effective carrier proteins for meningococcal serogroup C polysaccharide and could produce a vaccine to protect against meningococcal disease and to augment protection against pertussis. [source] Epstein-Barr virus (EBV) serology for predicting distant metastases in a white juvenile patient with nasopharyngeal carcinoma and no clinical response to EBV lytic induction therapyHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 11 2006Servi J. C. Stevens PhD Abstract Background. We describe a case of a 16-year-old white girl with Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC). Methods. At diagnosis, the patient had characteristic immunoglobulin (Ig)A and IgG responses to EBNA1, viral capsid antigen (VCA)-p18, and early antigens (EAs), with no detectable EBV DNA in her blood. Combined chemotherapy and radiotherapy resulted in complete remission. Eighteen months later, the patient's IgA responses to EBNA1 and p18 and both IgA and IgG anti-EA increased, without apparent recurrence. Five months later, lung metastases were found. She underwent surgical removal of the lung metastases and conventional chemotherapy, but had intraabdominal lymph node metastasis and mediastinal lesions develop. The patient was then treated with a novel treatment consisting of 5-fluorouracil plus valproic acid and subsequent valganciclovir to induce lytic EBV replication. This resulted in the first detectable EBV DNA levels in the blood but did not result in clinical response. Results. The patient's disease progressed, and the patient declined further cancer treatment and died. Conclusion. In contrast to EBV DNA load, EBV serology was useful in predicting distant NPC metastasis after initial complete remission in this patient. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] Adjuvant effects of CpG oligodeoxynucleotides on responses against T-independent type 2 antigensIMMUNOLOGY, Issue 1 2001J. Kovarik Summary Oligodeoxynucleotides containing CpG motifs (CpG-ODN) are potent in vitro B-cell activators and they have been successfully used to increase in vivo antibody responses to T-dependent peptide and protein antigens. In contrast, the use of CpG-ODN to enhance in vivo antibody responses to various T-independent type 2 (TI-2) antigens has recently generated contradictory results. In this study, we compared the CpG-ODN stimulatory effect on antibody responses of adult and young BALB/c mice to trinitrophenylaminoethyl-carboxymethyl (TNP) -Ficoll and to polysaccharides (PS) from several distinct serotypes of Streptococcus pneumoniae (SPn). CpG-ODN co-administration significantly enhanced antigen-specific immunoglobulin M (IgM), IgG, IgG1 and IgG2a titres to TNP-Ficoll. The depletion of CD4+ cells by monclonal antibodies (GK1.5) identified their essential role in CpG-ODN-mediated enhancement of antibody responses. In contrast to TNP-Ficoll, CpG-ODN failed to enhance IgM and IgG responses to any of the 18 SPnPS serotypes tested. Providing T-cell epitopes by the conjugation of SPnPS to the carrier protein tetanus toxoid again allowed CpG-ODN to mediate enhancement of IgG, IgG2a and IgG3 responses to most SPnPS serotypes. Thus, antigen-presenting cell/T-cell interaction appears to largely mediate the in vivo influence of CpG-ODN on antibody responses to TI-2 antigens. In early life, additional factors limit CpG-ODN modulation of antibody responses to TI-2 antigens. [source] Periodontal infection profiles in type 1 diabetesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2006Evanthia Lalla Abstract Objectives: We investigated the levels of subgingival plaque bacteria and serum IgG responses in patients with type 1 diabetes and non-diabetic controls of comparable periodontal status. Material and Methods: Fifty type 1 diabetes patients (mean duration 20.3 years, range 6,41) were age-and gender-matched with 50 non-diabetic individuals with similar levels of periodontal disease. Full-mouth clinical periodontal status was recorded, and eight plaque samples/person were collected and analysed by checkerboard hybridization with respect to 12 species. Homologous serum IgG titres were assessed by checkerboard immunoblotting. In a sub-sample of pairs, serum cytokines and selected markers of cardiovascular risk were assessed using multiplex technology. Results: Among the investigated species, only levels of Eubacterium nodatum were found to be higher in diabetic patients, while none of the IgG titres differed between the groups, both before and after adjustments for microbial load. Patients with diabetes had significantly higher serum levels of soluble E-selectin (p=0.04), vascular cell adhesion molecule-1 (VCAM-1; p=0.0008), adiponectin (p=0.01) and lower levels of plasminogen activator inhibitor-1 (PAI-1; p=0.02). Conclusions: After controlling for the severity of periodontal disease, patients with type 1 diabetes and non-diabetic controls showed comparable subgingival infection patterns and serum antibody responses. [source] Differential gender effects of a reduced-calorie diet on systemic inflammatory and immune parameters in nonhuman primatesJOURNAL OF PERIODONTAL RESEARCH, Issue 5 2008J. L. Ebersole Background and Objective:, Dietary manipulation, including caloric restriction, has been shown to impact host response capabilities significantly, particularly in association with aging. This investigation compared systemic inflammatory and immune-response molecules in rhesus monkeys (Macaca mulatta). Material and Methods:, Monkeys on continuous long-term calorie-restricted diets and a matched group of animals on a control ad libitum diet, were examined for systemic response profiles including the effects of both gender and aging. Results:, The results demonstrated that haptoglobin and ,1-antiglycoprotein levels were elevated in the serum of male monkeys. Serum IgG responses to Campylobacter rectus, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were significantly elevated in female monkeys. While only the antibody to Fusobacterium nucleatum was significantly affected by the calorie-restricted diet in female monkeys, antibody levels to Prevotella intermedia, C. rectus and Treponema denticola demonstrated a similar trend. Conclusion:, In this investigation, only certain serum antibody levels were influenced by the age of male animals, which was seemingly related to increasing clinical disease in this gender. More generally, analytes were modulated by gender and/or diet in this oral model system of mucosal microbial challenge. [source] Detection of IgM and IgG antibodies to Cryptococcus neoformans proteins in blood donors and HIV patients with active cryptococcosisMYCOSES, Issue 2 2009H. C. Chai Summary The serological responses to Cryptococcus neoformans proteins of blood donors and HIV patients with active cryptococcosis from a tropical region were investigated in this study. Exposure to C. neoformans, an organism ubiquitous in the environment, contributes to the antibody responses observed in the blood donors. IgG responses to cryptococcal proteins were stronger than IgM responses in most sera tested in this study. A 53-kDa cryptococcal protein fragment was identified as the most immunoreactive protein on the IgM immunoblots of both blood donors and patients. Overall, there was no obvious difference in IgG responses of patients when compared with blood donors. Some immunogenic protein fragments (27.5, 76, 78 and 91.5 kDa) were detected at least two times more frequently on IgM immunoblots of patients compared with those of blood donors. It is yet to be investigated whether the proteins identified in this study may have any potential to be used as biomarker for cryptococcosis. [source] ORIGINAL ARTICLE: A Multi-Subunit Chlamydial Vaccine Induces Antibody and Cell-Mediated Immunity in Immunized Koalas (Phascolarctos cinereus): Comparison of Three Different AdjuvantsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2010Alison J. Carey Citation Carey AJ, Timms P, Rawlinson G, Brumm J, Nilsson K, Harris JM, Beagley KW. A multi-subunit chlamydial vaccine induces antibody and cell-mediated immunity in immunized koalas (Phascolarctos cinereus): comparison of three different adjuvants. Am J Reprod Immunol 2010; 63: 161,172 Problem, Chlamydial infections represent a major threat to the survival of the koala. Infections caused by Chlamydia pecorum cause blindness, infertility, pneumonia and urinary tract infections and represent a threat to the survival of the species. Little is known about the immune response in koalas, or the safety of commonly used adjuvants for induction of protective systemic and mucosal immunity. Method of study, In the present study, we immunized 18 healthy female koalas subcutaneously with a combination of three chlamydial antigens [major outer membrane protein (MOMP), NrdB and TC0512 (Omp85)] mixed with one of three different adjuvants [Alhydrogel, Immunostimulating Complex (ISC) and TiterMax Gold]. Results, All adjuvants induced strong neutralizing IgG responses in plasma against the three antigens with prolonged responses lasting more than 270 days seen in Alhydrogel and ISC immunized animals. Cloacal IgG responses lasting >270 days were also induced in ISC-immunized animals. Chlamydia -specific peripheral blood mononuclear cell proliferative responses were elicited by both Alhydrogel and ISC, and these lasted >270 days in the ISC group. Conclusion, The data show that a multi-subunit chlamydial vaccine, given subcutaneously, can elicit Chlamydia -specific cell-mediated and antibody responses in the koala demonstrating that the development of a protective vaccine is feasible. [source] Elevated Epstein,Barr virus-encoded nuclear antigen-1 immune responses predict conversion to multiple sclerosisANNALS OF NEUROLOGY, Issue 2 2010Jan D. Lünemann MD Objective The aims of the study were to determine the immune responses to candidate viral triggers of multiple sclerosis (MS) in patients with clinically isolated syndromes (CISs), and to evaluate their potential value in predicting conversion to MS. Methods Immune responses to Epstein,Barr virus (EBV), human herpesvirus 6, cytomegalovirus (HCMV), and measles were determined in a cohort of 147 CIS patients with a mean follow-up of 7 years and compared with 50 demographically matched controls. Results Compared with controls, CIS patients showed increased humoral (p < 0.0001) and cellular (p = 0.007) immune responses to the EBV-encoded nuclear antigen-1 (EBNA1), but not to other EBV-derived proteins. Immunoglobulin G (IgG) responses to other virus antigens and frequencies of T cells specific for HCMV and influenza virus gene products were unchanged in CIS patients. EBNA1 was the only viral antigen with which immune responses correlated with number of T2 lesions (p = 0.006) and number of Barkhof criteria (p=0.001) at baseline, and with number of T2 lesions (p = 0.012 at both 1 and 5 years), presence of new T2 lesions (p = 0.003 and p = 0.028 at 1 and 5 years), and Expanded Disability Status Scale score (p = 0.015 and p = 0.010 at 1 and 5 years) during follow-up. In a univariate Cox regression model, increased EBNA1-specific IgG responses predicted conversion to MS based on McDonald criteria (hazard ratio [95% confidence interval], 2.2 [1.2-4.3]; p = 0.003). Interpretation Our results indicate that elevated immune responses toward EBNA1 are selectively increased in CIS patients and suggest that EBNA1-specific IgG titers could be used as a prognostic marker for disease conversion and disability progression. ANN NEUROL 2010;67:159,169 [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] Developments in allergen-specific immunotherapy: from allergen extracts to allergy vaccines bypassing allergen-specific immunoglobulin E and T cell reactivityCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2010M. Focke Summary Allergen-specific immunotherapy (SIT) is the only specific and disease-modifying approach for the treatment of allergy but several disadvantages have limited its broad applicability. We argue that the majority of the possible disadvantages of SIT such as unwanted effects, poor efficacy and specificity as well as inconvenient application are related to the poor quality of natural allergen extracts, which are the active ingredients of all currently available allergy vaccines. Because of the progress made in the field of molecular allergen characterization, new allergy vaccines based on recombinant allergens, recombinant hypoallergenic allergen derivatives and allergen-derived T cell peptides have entered clinical testing and hold promise to reduce the side-effects and to increase the specificity as well as the efficacy of SIT. Here, we present a refined immunotherapy concept, which is based on the use of peptides derived from allergen surfaces that exhibit reduced, allergen-specific IgE as well as T cell reactivity. These peptides when fused to non-allergenic carriers give rise to allergen-specific protective IgG responses with T cell help from a non-allergenic carrier molecule. We summarize the experimental data demonstrating that such peptide vaccines can bypass allergen-specific IgE as well as T cell activation and may be administered at high doses without IgE- and T cell-mediated side-effects. Should these peptide vaccines prove efficacious and safe in clinical trials, it may become possible to develop convenient, safe and broadly applicable forms of SIT as true alternatives to symptomatic, drug-based allergy treatment. Cite this as: M. Focke, I. Swoboda, K. Marth and R. Valenta, Clinical & Experimental Allergy, 2010 (40) 385,397. [source] Anti-bacterial IgE in the antibody responses of house dust mite allergic children convalescent from asthma exacerbationCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2009B. J. Hales Summary Background Atopic sensitization to the house dust mite (HDM) is associated with altered antibody responses to the nasopharyngeal colonizing bacterium Haemophilus influenzae and children admitted to the emergency department for asthma exacerbation have reduced IgG responses to HDM allergens. Objective To investigate anti-bacterial and anti-allergen antibody responses during convalescence from asthma exacerbation and differences found in exacerbations associated with and without viral infection. Results IgE antibodies to the P6 bacterial antigen increased in 60% of sera during convalescence and for many children achieved titres as high as IgE titres to allergens. In contrast IgE anti-HDM titres declined during convalescence. The anti-bacterial IgE titres were the same in subjects with and without virus infection while the anti-HDM IgE declined more rapidly in virus-infected subjects. IgG titres to the major HDM allergens showed no consistent increase and the overall IgG anti-HDM titres even declined in subjects without a virus infection. Anti-bacterial IgG antibodies in contrast to IgE did not change. Patients with frequent episodic or persistent asthma had similar IgE anti-bacterial titres to patients with infrequent asthma during the acute phase, although they had reduced IgG titres to both the bacteria and the HDM. Conclusions During the period following an acute exacerbation of asthma there was a marked and specific increase in anti-bacterial IgE compared with a reduced IgE response to HDM. This provides further support for the concept of T-helper type 2 responses to bacterial antigens playing a role in asthma pathogenesis. [source] Patterns of immunoglobulin G responses to egg and peanut allergens are distinct: ovalbumin-specific immunoglobulin responses are ubiquitous, but peanut-specific immunoglobulin responses are up-regulated in peanut allergyCLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2007S. S. Tay Summary Background The clinical significance of food-specific IgG subclasses in food allergy and tolerance remains unclear. Specific IgG titres are often reported in non-standardized units, which do not allow comparisons between studies or allergens. Objective To quantify, in absolute units, ovalbumin (OVA)- and peanut-specific IgG levels in children with peanut or egg allergy (active or resolved) and in non-allergic controls. Methods Children aged 1,15 years were recruited. Peanut allergy was diagnosed by convincing history and a 95% predictive level of specific IgE; egg allergy or resolution was confirmed by oral challenge. Serum IgG, IgG1 and IgG4 levels (,g/mL) to OVA and peanut extract were quantified by ELISA. Results OVA- and peanut-specific IgG was detected in all subjects. In non-allergic controls (n=18), OVA-specific IgG levels were significantly higher than peanut-specific IgG (median ,g/mL IgG=15.9 vs. 2.2, IgG1=1.3 vs. 0.6, IgG4=7.9 vs. 0.7; P<0.01). There were no differences in OVA-specific IgG, IgG1 and IgG4 between egg-allergic (n=40), egg-resolved (n=22) and control (n=18) subjects. In contrast, peanut-specific IgG (median ,g/mL IgG=17.0, IgG1=3.3, IgG4=5.2) were significantly higher in peanut-allergic subjects (n=59) compared with controls and with non-peanut-sensitized but egg-allergic subjects (n=26). Overall, the range of IgG4 was greater than IgG1, and IgG4 was the dominant subclass in >60% of all subjects. Conclusion OVA-specific IgG levels of egg-allergic, egg-resolved or control groups are not distinguishable. Higher peanut-specific IgG levels are associated with clinical allergy, but the range of IgG titres of the allergic and control groups overlapped. Hence, OVA and peanut-specific IgG measurements do not appear to be of diagnostic value. Strong IgG responses to OVA may be a normal physiological response to a protein frequently ingested from infancy, whereas up-regulated IgG responses in peanut allergy may be indicative of a dysregulated immune response to peanut allergens. [source] The recombinant major allergen of Parietaria judaica and its hypoallergenic variant: in vivo evaluation in a murine model of allergic sensitizationCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2004A. Orlandi Summary Background Par j 1 represents the major allergenic component of Parietaria judaica pollen. Its three-dimensional structure is stabilized by four disulphide bridges. A family of three-dimensional mutants of the recombinant Par j 1 (rPar j 1) allergen, showing reduced allergenicity and retained T cell recognition has been recently developed by site-directed mutagenesis. Objective To develop and characterize a murine model of IgE sensitization to rPar j 1. To evaluate similarities between the murine model and the human IgE response. To investigate in this model the recognition of a hypoallergenic mutant of Par j 1, and to study the immune responses elicited in mice by the mutant itself. Methods BALB/c mice were sensitized by two intraperitoneal immunizations with rPar j 1 in alum on days 0 and 21. Allergen-specific serum IgE and IgG responses were studied by direct ELISA and immunoblotting, ELISA inhibition and competitive ELISA. Cell proliferation was evaluated in splenocyte cultures. Results Sensitization with rPar j 1 induced high levels of IgE and IgG1 vs. low levels of IgG2a. Mouse antibodies specific to rPar j 1 were able to compete with human IgE for recognition of rPar j 1. IgE from mice immunized with rPar j 1 showed a significantly reduced binding activity towards the hypoallergenic variant rPjC, which lacks three disulphide bridges. On the contrary, rPjC was recognized by IgG1 and IgG2a antibodies as well as rPar j 1. The proliferative response to rPjC by splenocytes from mice immunized with rPar j 1 was comparable to that stimulated by rPar j 1. Immunization with rPjC induced low levels of IgE antibodies to the rPjC itself, while IgG and proliferative responses were similar to those induced by rPar j 1. Conclusion Conformational variants of allergens, displaying reduced allergenicity accompanied by retained IgG and T cell recognition, offer a safe, specific and flexible approach to immunotherapy of type I allergy. Our mouse model of IgE sensitization to a recombinant allergen, mimicking the human response to its native counterpart, could provide valuable information for pre-clinical testing of such hypoallergenic molecules. [source] | ||||||||||||||||||||||||||||