摘要:

ABSTRACTWe observed that an influenza-specific cytotoxic T lymphocyte (CTL) clone (B7B7) stimulated with peptide-antigen could produce TNF-α and IFN-γ simultaneously. The culture supernatant containing both TNF-α and IFN-γ of antigen-stimulated CTL clone B7B7 significantly enhanced the lysis of influenza A/PR/8 virus-infected L-M2d6 cells or Meth A cells. Enhanced lysis of influenza virus-infected cells by the supernatants was inhibited by pretreatment of the supernatant with antimurine TNF-α antibody and antimurine IFN-γ antibody. In addition to a single CTL clone, we observed that bulk-cultured CTLs were able to produce TNF and IFN when incubated with target cells. These results suggest that the protective mechanism mediated by TNF-α and IFN-γ secreted from CTL may be possible in the course of an influenza in

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.1

年代:1993

数据来源: MAL

摘要:

ABSTRACTPolymerized human serum albumin may play a role in the entry of hepatitis B virus into hepatocytes, and antibodies to polyalbumin that frequently appear during acute hepatitis may aid the process of viral clearance. We developed an enzyme-linked immunosorbent assay for antibodies to polymerized woodchuck albumin to enable us to evaluate further the role of these antibodies in an animal model system. Sera from 17 uninfected adult woodchucks and 8 newborns showed no binding to control plates coated with woodchuck transferrin, woodchuck albumin, or polymerized human serum albumin. One of 8 newborn animals demonstrated a significant antibody titer to polymerized woodchuck albumin, and 16 of 17 adults without evidence of prior woodchuck hepatitis virus infection had measurable serum antibody titers. Antibodies to polymerized woodchuck albumin could be adsorbed by prior incubation with the antigen. In 2 animals subjected to experimental infection, significant rises in polyalbumin antibody were seen. When 4 adult woodchucks were immunized with woodchuck polyalbumin, significant increases in antibody titer were observed in 2 of the 4 animals. Of the 4 immunized and 4 controls subsequently challenged with woodchuck hepatitis virus, 7 became viremic and all 8 developed antibody to woodchuck hepatitis virus core antigen. We conclude that naturally occurring antibodies to polymerized woodchuck albumin are observed in most adult woodchucks in the absence of woodchuck hepatitis virus infection and do not seem to confer immunity against infection with this virus.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.13

年代:1993

数据来源: MAL

摘要:

ABSTRACTIn mice the immune response to HSV-1 includes a brisk Tc response that is intimately associated with the control of infection. This report evaluated the Tc response to gC, one of the envelope glycoproteins of HSV-1. This protein was recognized as a target antigen for Tc from HSV-1 immune mice only if they expressed the H-2KbMHC allele. However, even within these "responder" strains of mice the proportion of gC specific Tc was highly variable. The failure of HSV-induced Tc to recognize gC in the context of other class 1 MHC haplotypes (H-2dand H-2k) was demonstrable at the clonal level and could not be attributed to peculiarities of the recombinant constructs. Surprisingly, despite the inability of H-2k-restricted, HSV-1-induced Tc to recognize gC, when a vaccinia gC virus construct was used to immunize H-2kstrains of mice it showed a variable ability to induce memory Tc populations capable of lysing HSV-1-infected autologous cells. Of added importance was the correlation of this induced Tc response with optimum protection against subsequent challenge with HSV-1. This demonstrated that despite the presence of suitable epitopes, the context of the immunogen would also influence its ability to induce Tc. Consequently, the potential repertoire of available HSV-1-specific Tc specificities is larger than indicated by studying animals immunized with HSV.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.21

年代:1993

数据来源: MAL

摘要:

ABSTRACTTwo mutant viruses, HSV-2 XD192 and HSV-1 1716, failed to generate zosteriform lesions when injected in high dose into BALB/c and C3H mice. Mice exposed to mutant viruses were solidly immune to challenge by wild-type homologous or heterologous virus. However, at lower immunizing doses protection was evident against lethality, but not skin lesions, especially in the case of mutant XD192. Protection could be conferred with lymphoid cells from mutant virus immune mice and again, protection against lethality was more frequent than prevention of skin lesions. On the basis of cell fractionation studies, protection against lethality was assumed to be principally the function of CD8+T lymphocytes. The implications of the results in terms of vaccine development were briefly discussed.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.35

年代:1993

数据来源: MAL

摘要:

ABSTRACTTwo hundred and fifty apparently healthy pregnant women attending the Obstetrics and Gynecology Clinic of the Lagos University Teaching Hospital (LUTH), Lagos, Nigeria were screened for a comparison of the prevalence of HIV seropositivity and hepatitis B surface antigenemia (HBs Ag) amongst them. The Karpas AIDS cell test for HIV seropositivity and Bioman Hepatitis test kits were used as described by the manufacturers. HIV seropositive cases were confirmed using the Western blot test. Results revealed that out of the 250 pregnant women screened, 2 (0.8%) and 11 (4.4%) were HIV-1 and HBs Ag seropositive, respectively. However, the same 2 pregnant women now constituting 2 (18.2%) of the 11 HBs Ag positive pregnant women were simultaneously HIV-1 seropositive. Antibody to HIV-2 was not recorded in all HIV seropositive cases. This is the first report on the simultaneous prevalence of HBs Ag and HIV seropositivity among apparently healthy pregnant women in Lagos, Nigeria.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.43

年代:1993

数据来源: MAL

摘要:

ABSTRACTThe detection of antibody to the hepatitis C virus C100-3 antigen from the nonstructural region (NS3/NS4) of the viral genome was the first useful marker developed to detect past or potentially active infection with the hepatitis C virus. A systematic epitope survey of the nonstructural region has uncovered other immunogenic antigens. In order to assess the possible diagnostic utility of these antigens, their reactivity against a limited panel of sera from patients with chronic liver disease due to hepatitis C virus and other etiologies was tested. Antibody assays were performed using an immunoblot plaque assay and an enzyme-linked immunosorbent assay (ELISA). In a study of 16 C100-3-reactive individuals, all 16 patients were reactive using the plaque assay for the NS3 3′ (409-1-1) and NS3 5′ (C33u). In this same group of patients, antibodies by ELISA were reactive to NS3 3′ in 12 of 16 patients (75%), NS3 5′ in 15 of 16 patients (93%), and a capsid antigen (NC450) in 14 of 16 patients. In a group of five patients who were diagnosed with cryptogenic liver disease (C100-3 negative), 4 of 5 patients were reactive for antibody to all of the above epitopes. In a survey of 23 patients with other forms of chronic liver disease (nonviral liver disease, hepatitis B, alcoholic liver disease, cholestatic liver disease, and autoimmune hepatitis), only 1 of 23 patients was reactive for antibody to the C100-3 and 4 of 23 patients were reactive for antibodies to structural and nonstructural regions of the virus. The addition of other immunoreactive antigens to those already included in the available first generation test may result in further improvements in serological screening for present or past hepatitis C virus in

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.49

年代:1993

数据来源: MAL

摘要:

ABSTRACTInfluenza A virus-specific MHC class I-restricted cytotoxic T lymphocyte (CTL) activities among young and elderly adults were compared. Peripheral blood lymphocytes from 10 young adults, (mean age 27 ± 2.4 years) and elderly persons (mean age 71 ± 1.6 years) were stimulated with influenza A/Taiwan/1/86 (H1N1) virus for 7 days and assayed for lytic activity against A/Taiwan, A/Shanghai (H3N2), and B/USSR virus-infected autologous target cells. Young adults exhibited significantly higher influenza A cross-reactive CTL activity against A/H1N1 and A/H3N2 target cells when compared to aged persons. This was true at all effector-to-target cell ratios tested. Negligible lysis of B/USSR-infected target cells or nonautologous A/Taiwan-infected cells was observed. The number of leukocytes recovered per milliliter of blood was also significantly higher in young adults than in old donors; however, the percentage of CD45+(common leukocyte antigen), CD3+(T cells), CD4+(T helper), and CD8+(T cytotoxic/suppressor) as well as the CD4+/CD8+ratios was similar in both groups. Depletion of cells with monoclonal antibodies indicated that the effector cells were CD8+T cells. Serum-neutralizing antibody (Nt Ab) titers were similar among young and elderly persons and there was no correlation between Nt Ab and CTL activity. These results demonstrate a reduced influenza virus-specific MHC class I-restricted CTL activity among elderly persons. The deficiency in this cell-mediated immune function may contribute to the morbidity and mortality from influenza virus infections in this populatio

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.55

年代:1993

数据来源: MAL

摘要:

ABSTRACTWe studied 152 healthy pregnant women and their 156 newborns for markers of hepatitis B virus (HBV) infection in Dakar, Senegal. Of these, 120 mothers (79%) had antibodies to the hepatitis B core antigen (anti-HBc), 21 (13.8%) were hepatitis B surface antigen (HBs Ag) positive, including 2/21 (9.5%) hepatitis B core-associated antigen (HBe Ag) positive and 1/21 (4.7%) HBV DNA positive. At birth, 11 (7%) infants were HBs Ag positive; 9/11 had an HBs Ag positive mother. Ten of these HBs Ag positive-born infants were investigated at 6–7 months: 5 were strongly HBs Ag positive and developed antibodies to HBs Ag, HBc Ag or HBe Ag; these 5 (3.2% of the total) probably became chronic carriers of HBV. The 5 others were HBs Ag negative and 4/5 did not develop antibodies against HBV Ag; HBs Ag positivity at birth was likely due to contamination of the mother's blood. Thirty-one of the 145 HBs Ag negative-born infants were studied at 6–7 months and remained HBs Ag negative. However, 5 (16%) showed evidence of HBV infection occurring between 0 and 6 months, as shown by the development of antibodies to HBs Ag, HBc Ag, and/or HBe Ag. Despite the low prevalence of HBV DNA and HBe Ag in HBs Ag positive African mothers, this study shows the occurrence of perinatal transmission of HBV in West Africa, in contrast with previous studies. Perinatal HBV transmission could explain the HBV vaccination failure recently reported in children in Sene

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.65

年代:1993

数据来源: MAL

摘要:

ABSTRACTAntiidiotypic antibodies can be envisioned as an alternative approach in the development of vaccines against influenza virus, which exhibits natural antigenic variations. In our work, we obtained two polyclonal cross-reactive anti-Id antibodies against PY102, VM113, and VM202 mAbs, which in turn are specific respectively for PR8 virus and laboratory-induced virus variants (PY102-V1 and VM113-V1). With these cross-reactive anti-Id antibodies, we were able to elicit anti-HA antibodies in mice. In comparing the anti-HA antibody response in animals injected with anti-Id antibodies to those immunized with PR8 influenza virus, we demonstrated that the HI titer was higher after virus immunization and that the PR8 virus boost was more efficient in this group. Our results showed that the polyclonal cross-reactive anti-Id antibodies were more efficient than the individual anti-Ids at eliciting responses. At the same time, we demonstrated that PR8-primed T cells, cultured with B cells from animals immunized with anti-Id antibodies, were able to produce anti-PR8 antibodies subsequent to stimulation with influenza virus.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.75

年代:1993

数据来源: MAL

摘要:

ABSTRACTThe repertoire of antigen-specific receptors expressed on T lymphocytes is shaped by fixed genetic and variable environmental selective pressures. Recent technological advances have enabled the analysis of T-cell receptor (TCR) expression in the context of selective pressures arising through normal immune system development and also through pathological features of disease. The pathological features of acquired immune deficiency syndrome (AIDS) are reflected by selective depletion of particular T lymphocyte subsets and expansion of others. An important question concerning the immunopathogenesis of AIDS is whether or not the perturbation of the CD4+and CD8+T-cell subsets following infection with human immunodeficiency virus (HIV) is selective based on TCR variable (V) region gene expression. To address this question, we have functionally analyzed TCR V gene expression on CD8+cytotoxic T lymphocytes from HIV-1-infected individuals. This was done using monoclonal antibodies against individual TCR V regions to trigger redirected cytolysis in51Cr release assays. The percent specific lysis induced by each antibody functionally measures the representation of the TCR V region gene product it is specific for. Relative to non-HIV-infected controls and asymptomatic HIV-infected individuals with only moderate CD4 lymphocyte depletion, HIV-infected individuals with low CD4 lymphocyte counts exhibited skewed patterns of TCR V region representation. Therefore, the perturbation within the CD8+cytotoxic T lymphocyte repertoire in HIV infection appears to be selective based on TCR V region usage, increasingly so as disease progresses. The TCR V genes affected varied between different HIV-infected individuals and skewing detected in functional assays was not always apparent by flow cytometric analysis. These results suggest that HIV infection causes generalized effects on the T-cell repertoire, which are reflected in the relative TCR V gene representation of the CD8+ cytotoxic T lymphocyte population in peripheral blood.

ISSN:0882-8245    

DOI:10.1089/vim.1993.6.85

年代:1993

数据来源: MAL