Home  About us  Contact
 

Multiple Antigens (multiple + antigen)

Distribution by Scientific Domains
Medical Sciences75%

Selected Abstracts

Analysis of CD8 T-cell response by IFN, ELISPOT and H-2Ld/ pRL1a tetramer assays in pRL1a multiple antigen peptide-immunized and RL male 1-bearing BALB/ c and (BALB/c×C57BL/6) F1 mice

CANCER SCIENCE, Issue 3 2004
Itsuro Takada
We previously identified an H-2Ld -binding peptide pRL1a (IPGLPLSL) on RL male 1 that is predominantly recognized by cytotoxic T-lymphocytes (CTLs). MAP is a multibranched lysine core with antigenic peptides. Immunization of BALB/c mice with pRL1a MAP effectively induced pRL1a CTLs. Here, we demonstrate the presence of pRL1a-recognizing CD8+ T-cells in pRL1a MAP-immunized and RL male 1-bearing BALB/c and (BALB/ cxC57BL/6)F1 mice by using IFN, ELISPOT and H-2Ld/pRL1a tetramer assays. A few IFN, ELISPOTs and no tetramer-positive cells were detected ex vivo in spleen cells from BALB/c mice immunized with pRL1a MAP. After a single in vitro stimulation with RL male 1, 432 and 741 IFN, ELISPOTs/105 cells were detected and tetramer-positive CD8+ T-cells occurred at relative frequencies of 5.7% and 30.8% in splenic CD8+ T-cells from mice that had been doubly and triply immunized, respectively, against pRL1a MAP. Tetramer-positive cells displayed two distinct cell populations, CD62Llow and CD62Lhigh. Secondary in vitro stimulation expanded CD62Lhigh cells more efficiently than CD62Llow cells. Furthermore, a higher frequency of IFN,-producing and tetramer-positive CD8+ T-cells was detected ex vivo in RL male 1-bearing semi-allogeneic (BALB/cxC57BL/6)F1 than in BALB/c mice on day 14 after tumor inoculation. [source]

Multispecific responses by T cells expanded by endogenous self-peptide/MHC complexes

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2007
Guifang Cai
Abstract The paradox of autoreactivity to self-peptides in physiological as opposed to pathological immune responses is not well understood. Here, we directly examined the human T cell response to endogenous self-peptides in a series of healthy subjects. CFSE-labeled T cells were stimulated with unmanipulated antigen-presenting cells containing endogenous self-antigen, and the resulting CD4+ populations entering into cell cycle (CFSElow) or non-proliferating CD4+ cells (CFSEhigh) were single-cell sorted, cloned and screened against a panel of self-antigens and microbial recall antigens to interrogate their antigen reactivity. The percentage of CD4+ T cells entering cell cycle in response to self-peptide/MHC was calculated to be 0.04%, and entry into cell cycle was dependent upon CD28 costimulation. Clones derived from CFSElow T cells exhibited significantly greater cross-reactivity to multiple antigens than CFSEhigh clones or other CD4+ clones generated after microbial antigen stimulation. Sequencing the TCR, chains indicated that CFSElow clones were indeed clonal. These data demonstrate that T cell clones generated on stimulation by endogenous self-peptides exhibit a high degree of multispecificity, and we speculate that their multispecificity is based upon recognition of shared-backbone MHC determinants. [source]

Antibody convergence along a common idiotypic axis in immunodeficiency virus and hepatitis C virus infections

JOURNAL OF MEDICAL VIROLOGY, Issue 1 2002
Michael D. GrantArticle first published online: 29 NOV 200
Abstract The anti-idiotypic antibody 1F7 selectively binds antibodies against human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) gag, pol, and env proteins. We tested anti-hepatitis C virus (HCV) antibodies to investigate selection of the 1F7 idiotype on antibodies against other chronic pathogens. Twelve of 15 HCV-seropositive individuals co-infected with HIV had detectable antibodies against recombinant HCV core, 4 against HCV NS4 protein, and 3 against HCV NS3 protein. All four HCV-seropositive, non-HIV-infected individuals had antibodies against HCV core and NS4, while 3 had antibodies against NS3. The 1F7 idiotype was frequently present on antibodies against each of the HCV antigens in the HIV co-infected and non-HIV-infected groups. Antibodies against HCV, including antibodies recognizing the putative principal neutralizing determinant of HCV E2 protein, displayed skewed ,/, light chain usage consistent with clonal dominance. These observations extend the association between expression of the 1F7 idiotype and abnormal B cell clonal dominance in HIV and SIV infection to HCV infection and suggest that early establishment of an oligoclonal antibody response against HCV may freeze the B cell repertoire, impair adaptation to emergent HCV variants, and favor escape from neutralizing antibodies. We also demonstrated that expression of the 1F7 idiotype extends beyond antibodies against multiple antigens of AIDS-causing retroviruses to include antibodies against multiple antigens of an unrelated chronic hepatitis virus. Thus, distinct pathogens establishing chronic infection in the face of strong humoral immune responses select antibodies along a common idiotypic axis of the immune network. J. Med. Virol. 66:13,21, 2002. © 2002 Wiley-Liss, Inc. [source]

Natural antibody response to Plasmodium falciparum Exp-1, MSP-3 and GLURP long synthetic peptides and association with protection

PARASITE IMMUNOLOGY, Issue 6-7 2004
V. Meraldi
SUMMARY A longitudinal study was undertaken in Burkina Faso among 293 children aged 6 months to 9 years in order to determine the correlation between an antibody response to several individual malarial antigens and malarial infection. It was found that the presence of a positive antibody response at the beginning of the rainy season to three long synthetic peptides corresponding to Plasmodium falciparum Exp-1 101,162, MSP-3 154,249 and GLURP 801,920 but not to CSP 274,375 correlated with a statistically significant decrease in malarial infection during the ongoing transmission season. The simultaneous presence of an antibody response to more than one antigen is indicative of a lower frequency of malarial infection. This gives scientific credibility to the notion that a successful malaria vaccine should contain multiple antigens. [source]