摘要:

ABSTRACTPeripheral autoreactive T cell response was evaluated by limiting dilution analysis of autologous mixed lymphocyte reaction cultures in 15 subjects at high risk for HIV infection and in 20 normal individuals. The two groups did not show a quantitative difference of peripheral autoreactive T cells, but they showed different kinetics. While controls provided a straight line passing through the origin, the majority of high risk individuals showed a curve with a limited linear portion at high cell concentration, indicating that different mechanisms regulate the autoreactive response in the two groups studied. A follow-up study performed in three high risk and three normal individuals revealed a time-dependent increase of peripheral autoreactive T cells only in high risk subjects. Such increase correlates with the decrease of CD4+ cell number and CD4+/CD8+ cell ratio. Furthermore, the proliferative response of the same three subjects to gp160 peptides suggests a specific cellular reactivity to HIV components. This work has potential importance in understanding some of the early events in HIV infection.

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.1

年代:1994

数据来源: MAL

摘要:

ABSTRACTDifficulties in the isolation and long-term maintenance of bovine herpesvirus-1 (BHV-1) specific T-cell clones have hindered the analysis of bovine cell-mediated immune response to this virus. In an effort to identify the T-cell epitopes of the virus, bovine murine T-cell hybridomas specific for BHV-1 were generated as an alternative to T-cell clones. Peripheral blood lymphocytes from a calf immunized with BHV-1 were restimulatedin vitrowith the virus to generate bulk T-cell cultures. The antigen-specific T-cell-enriched bulk culture lymphocytes were fused with the T-cell receptor-deficient mutant of the murine thymoma cell line BW 5147. T-cell hybridomas were screened for their ability to produce interferon-γ in response to BHV-1 stimulation. Hybridomas with various specificities were obtained. One of them was specific for the BHV-1 glycoprotein gI, two were specific for gIV, while three other hybridomas were specific for gIII. One hybridoma responded to stimulation with BHV-1, but not to any of the glycoproteins gI, gIII, or gIV, suggesting that proteins other than these major glycoproteins may be involved in the bovine T-cell response to BHV-1. Of these hybridomas, one was MHC Class I restricted, while all the others were Class II restricted

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.11

年代:1994

数据来源: MAL

摘要:

ABSTRACTImmunoglobulins are encoded by genes located in three different loci, the heavy chain (IgH), κ light chain (Igκ), and λ light chain (Igκ) loci. In mice, the κ/λ ratio of B cells is 95:5. In a previous study, we reported that κ gene deletion causes the alternative usage of λ1(93%) and λ2(7%) light chains, and that the κ anti-TNP repertoire is compensated for by the λ repertoire even though the latter is clonally restricted in K−/− mice. To investigate the contribution of λ antibodies to protection against virus, we compared K−/− mice with 129/Sv wild-type mice with respect to immune responses to influenza virus. PR8 virus immunized K−/− and 129/Sv mice showed no difference in the titer of anti-HA antibodies. Furthermore, the same immunized mice had sufficiently high neutralizing antibody titer to prevent infection when challenged with 7.5 × 104TCID50of PR8 virus. In addition, immunized K−/− mice were resistant to infection with 7.5 × 104TCID50and 7.5 × 105TCID50(10 and 100 LD50, respectively) of PR8 virus. Finally, K−/− mice are also capable of inducing cytotoxic T cells. These results suggest that the λ repertoire can compensate for the κ repertoire by generating a fully prote

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.25

年代:1994

数据来源: MAL

摘要:

ABSTRACTHealthy varicella zoster virus (VZV) immune subjects>55 years old, were immunized with 4,000 PFU of Oka strain VZV live vaccine or a similar amount of heat-inactivated vaccine. A subset of each group was also immunized with tetanus toxoid (TT) 3 months before receiving the VZV vaccine. The live and inactivated VZV vaccine groups had similar ages, sex distribution, and previous immunity to VZV. The live and inactivated VZV vaccines elicited similar increases in the frequency in blood of VZV-specific T cells,in vitrointerferon-γ production, and serum antibody levels both 3 and 12 months after immunization. Individuals with the highest responder cell frequency (RCF) at entry had the highest postimmunization RCF following either vaccine. There was no correlation at entry between the RCF to TT or RCF to VZV. There was a weak (P= 0.05) correlation in the incremental response to TT and VZV among individuals who responded to both vaccines. Entry variables that did not correlate with the response included percent of T cells or the CD45R0 (memory) T cell subset in blood, serum antibody levels, or amount of interferon-γ production. The results indicate that the inactivated vaccine is safe for VZV-immune subjects and boosts their antibody and T-cell responses as effectively as the live vaccine for at least 1 year following immunizatio

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.31

年代:1994

数据来源: MAL

摘要:

ABSTRACTWe investigated the proliferative response and IL-2 receptor (IL-2R) expression in peripheral blood mononuclear cells (PBMC) activated with anti-CD3 mAb alone or in combination with anti-CD28 mAb in a group of hepatitis C virus (HCV)-infected patients with detectable viremia demonstrated by "nested" PCR. PBMC from HCV patients and controls showed similar proliferative responses either to anti-CD3 mAb, 64.1, and/or to anti-CD28 mAb, 9.3. No differences were found in anti-CD3 or anti-CD3 plus anti-CD28-induced proliferative responses between patients who demonstrated circulating PBMC bearing HCV-RNA when compared to those with negative HCV-RNA PBMC. Moreover, flow cytometry studies confirmed that anti-CD3 alone or in combination with anti-CD28 were able to induce a significant increase of IL-2R expression in patients or controls PBMC. Both groups showed similar basal CD28 expression. These results indicate that both CD3- and CD28-activating pathways are preserved in HCV-infected patients with chronic active liver disease.

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.37

年代:1994

数据来源: MAL

摘要:

ABSTRACTThe immunogenicity of a human immunodominant T-cell epitope C9 (residues 205–233) of rubella virus capsid protein was studied in three strains of mice using C9 lipopeptide. This peptide induced strong T-cell responses in all three strains of mice. The minimal T-cell epitope C9B (residues 205–216) recognized by human T cells with HLA-DR4 phenotype did not specifically stimulate proliferation of T cells from micein vitro. T cells specific for C9 from immunized mice were shown to be CD4+, in agreement with results of similar studies in RV-seropositive hum

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.41

年代:1994

数据来源: MAL

ISSN:0882-8245    

DOI:10.1089/vim.1994.7.47

年代:1994

数据来源: MAL