Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors studied the immune status of 14 HIV-infected patients, 6 of whom had lymphadenopathy, 4 were diagnosed as having AIDS-related complex and 4, a full-blown AIDS. Analysis of laboratory findings showed that of predictive value are serum levels of immunoglobulin B, a CD4 cell count less than 200, reduced populations of CD20 and CD16 lymphocytes, and a depressed response to pokeweed mitogen. Based on the clinical manifestations and laboratory results, three stages characterizing the immune system in HIV infection have been identified.
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PMID:[The possibilities of using immunological indices as criteria for determining the stage of HIV infection and the disease prognosis]. 128 13

The mechanism of transmission of HIV from the male to the female genital tract or in the reverse order is not clear. CD4 glycoprotein is the receptor for HIV and Langerhans cells and the related dendritic cells could play a role in the initial transmission of HIV. Fc receptors (FcR) for IgG might be involved in antibody-mediated binding of HIV. We carried out an immunohistological study of normal human cervical and vaginal epithelia for the presence of CD4 glycoprotein, Langerhans cells and FcR to IgG. CD4+ glycoprotein was not found in the vaginal or cervical epithelium, with the exception of a few endocervical epithelial cells. A small number of CD4+ mononuclear cells were found in the endocervical epithelium of a third of the specimens but a large number of CD4+ cells was found in the submucosa of most of the cervical and vaginal specimens. Langerhans cells expressing CD4, HLA class II, Fc gamma R2 and Fc gamma R3 were detected in most vaginal, ectocervical and transformation zone epithelia and in 9/14 endocervical tissues. Fc gamma R3 was detected in about two-thirds of the columnar endocervical epithelium and the transformation zone. A smaller number of specimens expressed Fc gamma R2 in these epithelia, but Fc gamma R1 was not detected. We then demonstrated mRNA for Fc gamma R3 in the columnar endocervical epithelial cells and transformation zone by in situ hybridization, using a CD16-RNA probe. Fc gamma R3 and Fc gamma R2 gene transcripts were also found in fetal cervical tissue by applying the polymerase chain reaction to amplify portions of the Fc gamma R3 and Fc gamma R2 coding sequences in cDNA prepared from fetal RNA. HLA-DR was found in the endocervical cells, transformation zone and in Langerhans cells of all specimens. The presence of Langerhans cells, Fc gamma receptors and HLA class II antigen offers three potential mechanisms for cervico-vaginal HIV transmission: (i) direct HIV infection of Langerhans cells, (ii) binding of HIV antibody complexes to cervical epithelial Fc gamma receptors and (iii) binding of HIV infected CD4+ cells to cervical HLA class II antigen which may infect these or the adjacent CD4+ cells.
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PMID:Expression and gene transcript of Fc receptors for IgG, HLA class II antigens and Langerhans cells in human cervico-vaginal epithelium. 136 Aug 81

The IgG1 kappa, human monoclonal antibody (HMAb), F105, was studied for functional activity in antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC). F105 reacts with a discontinuous epitope on the CD4 binding site of the HIV-1 envelope glycoprotein, gp120, expressed on the surfaces of infected cells and neutralizes diverse viral strains at antibody concentrations readily achievable in humans. Neither F105 nor serum (diluted 1:50) from HIV seropositive donors mediate CDC against an SF2-infected cell line with rabbit or human sera as a source of complement. F105 and HIV-1 sera mediate ADCC against the SF2 strain. Normal human serum reduced spontaneous lysis of SF2 by peripheral blood monocytes (PBM). Although mixing of F105 with normal human serum reduced the lysis observed (36 +/- 8 vs. 42 +/- 8%), this still was significantly greater than lysis in media (30 +/- 5%) or normal human serum (23 +/- 6%) (p less than .05). A murine antibody to CD16 significantly reduced spontaneous lysis observed with media (30 +/- 5 vs. 18 +/- 3%) while normal mouse serum had no effect (31 +/- 7%). ADCC mediated by F105 is completely abrogated by the anti-CD16 antibody (42 +/- 8 vs. 22 +/- 4%), while only a fraction of ADCC mediated by HIV sera is inhibited by anti-CD16 (60 +/- 9 vs. 46 +/- 6%), suggesting that several populations of effector cells function in ADCC mediated by the polyclonal sera. Thus, F105, as opposed to polyclonal sera, mediates ADCC through a CD16+ PBM population.
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PMID:Functional activity of an HIV-1 neutralizing IgG human monoclonal antibody: ADCC and complement-mediated lysis. 138 Dec 1

Monocytes from human immunodeficiency virus (HIV) patients have an increased heterogeneity of phenotype and function. In a study of 120 HIV patients we have demonstrated that they have normal monocyte differential counts but that with progression of the disease an increasing proportion of monocytes show phenotypic and functional evidence for activation or maturation. A proportion of the monocytes are larger, with increased expression of CD11b, HLA-DR, CD45 and CD16. Concomitantly there was increased expression of TNF-alpha, high constitutive synthesis of PGE2 and high plasma IL-6 levels. This suggested that there exists a more dynamic situation of recruitment, activation and maturation of peripheral blood monocytes driven by HIV infection which results in a broader phenotypic profile.
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PMID:Heterogeneity of peripheral blood monocyte populations in human immunodeficiency virus-1 seropositive patients. 146 4

The rectal mucosa is one of the routes of transmission of the HIV virus, although the mechanism of transmission is unknown. We carried out an immunohistological investigation of human rectal epithelium to detect CD4 glycoprotein and Fc receptors (FcR) for immunoglobulin G which may be involved in HIV infection. CD4 was not detected by monoclonal antibodies (MAb) in normal rectal epithelial cells, although CD4+ mononuclear cells were found in the lamina propria of the rectum. FcR3 and FcR2 were, however, detected in surface or crypt epithelial cells of rectal mucosa, using MAb to CD16 and CD32, respectively. In addition, CD16 messenger RNA (mRNA) was found in surface and crypt epithelial cells by in situ hybridization using an RNA probe. FcR3 and FcR2 were also detected in fetal recto-colonic tissue by immunohistology, suggesting that these are constitutive receptors. FcR3 and FcR2 gene transcripts were then demonstrated in fetal recto-colonic tissue using the polymerase chain reaction to amplify a portion of FcR3 and FcR2 coding sequences in complementary DNA (cDNA) prepared from fetal RNA. These findings suggest the possibility that rectal transmission of HIV-antibody complexes might be facilitated by the expression of FcR3 and FcR2 in rectal epithelial cells.
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PMID:The expression of Fc receptors for immunoglobulin G in human rectal epithelium. 168 18

The susceptibility of HIV-1-infected CD4+ T cell lines to natural killer (NK) cell-mediated lysis was examined. Non-adherent peripheral blood mononuclear cells (PBMC) of healthy adults lysed HUT cells chronically infected with the IIIB or WMJ1 strains of HIV-1 to a significantly greater extent than uninfected HUT cells. In contrast, Sup-T1 cells chronically infected with these two strains of HIV-1 were not lysed to a greater extent than uninfected Sup-T1 cells. Clone A1.25-infected Sup-T1 (A1.25/Sup-T1), derived from IIIB-infected Sup-T1 cells (IIIB/Sup-T1), were susceptible to non-adherent PBMC-mediated lysis, as were A1.25-infected HUT cells (A1.25/HUT). When non-adherent PBMC were depleted of CD16 (Leu-11b)+ NK cells by treatment with anti-Leu-11b plus C, lysis of HIV-1-infected HUT or Sup-T1 cells was reduced to low levels, indicating that the lysis was mediated by NK cells. Expression of HIV antigens on these target cells did not correlate with their susceptibility to NK cell-mediated lysis. Depletion of interferon-alpha (IFN-alpha) producing HLA-DR+ cells from non-adherent PBMC had no effect on the magnitude of NK cell-mediated lysis of IIIB or WMJ1-infected HUT cells. In contrast, lysis of A1.25/Sup-T1 or A1.25/HUT cells required the presence of HLA-DR+ cells. IFN-alpha production appeared to be required for NK cell-mediated lysis of A1.25/Sup-T1 or A1.25/HUT cells, while lysis of HUT cells infected with the WMJ1 or IIIB strains of HIV-1 was IFN-alpha independent. These results indicate considerable variability in the susceptibility of different HIV-1 infected T cell lines to NK cell-mediated lysis and suggest the existence of alternative mechanisms of activation of NK cells for lysis of HIV-1-infected T cell lines.
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PMID:Natural killer cell-mediated lysis of T cell lines chronically infected with HIV-1. 196 36

It has been suggested that autoimmune phenomena contribute to the depletion of CD4+ T cells and the development of AIDS in HIV-1 infected humans based, in part, on observations that some HIV-1-infected humans have autoantibodies reactive with Ag expressed on uninfected CD4+ cells. In this study, 11 of 14 asymptomatic HIV-1-infected homosexuals and hemophiliacs, but none of 17 uninfected homosexuals or heterosexuals, were found to have cytotoxic lymphocytes in blood that can lyse uninfected CD4+ T cells from humans and chimpanzees but not human B lymphoblastoid cells or mouse T cells. The cytotoxic PBL were concluded to be CTL rather than NK cells, with the phenotype being CD3+, TCR-1 alpha beta+, CD8+, CD4-, CD16- based on findings that PBL-mediated lysis of uninfected CD4+ cells was 1) blocked by a mAb to CD3, which inhibits CTL but not NK activity; 2) diminished by treatment of PBL with a mAb to CD8 and C, but not by treatment with mAb to CD4 or CD16 and C; and 3) blocked by mAb WT31 directed against the TCR-1 alpha beta. In contrast, PBL from HIV-1-infected chimpanzees, which to date have not developed AIDS, lacked detectable CTL lytic for uninfected CD4+ cells.
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PMID:HIV-infected humans, but not chimpanzees, have circulating cytotoxic T lymphocytes that lyse uninfected CD4+ cells. 196 80

Natural killer (NK) cells may be of significance in host defense against viral infections. In the present study, NK cell function was examined in relation to different phases of human immunodeficiency virus (HIV) infection. Peripheral blood mononuclear cells were tested for NK cell activity using K562 cell targets in a 51Cr-release assay. NK cell responses of 26 HIV-seronegative homosexual men were not significantly different from those of 30 heterosexual controls. NK activity was significantly lower in cells from 32 homosexual men with documented, early-phase HIV infection (average of 14 months; range of 3-27 months) as compared with that of seronegative men. The NK cell response decreased with time, since men within the first year of infection (n = 15; average of 7.8 months; range of 3-12 months) had greater NK cell activity than did those with longer duration of infection (n = 17; average of 18.3 months; range of 13-27 months). The decrease in NK cell activity did not correlate with altered numbers of cells bearing CD16 (NK) markers in these subjects. NK cell-mediated lysis and cell numbers were most severely depressed in a separate group of HIV-seropositive men who had acquired immune deficiency syndrome (AIDS). In vitro treatment with alpha-interferon (alpha-IFN) significantly enhanced NK activity of effector cells obtained from men within the first year of HIV infection but not in those with longer-term infection. Our results indicate that NK cell function decreases over time within the first 2 years of HIV infection in homosexual men, and is lowest in HIV-seropositive men with overt AIDS.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Natural killer cell responses in homosexual men with early HIV infection. 214 Oct 73

In order to further investigate immune dysfunctions in HIV-1 infection, we studied the intensity of leukocyte function-associated antigen-1 (LFA-1) expression using a novel application of immunofluorescence analysis in 14 adults and 5 children seropositive for HIV-1 and in 14 healthy adults and 5 healthy children seronegative for HIV-1. While almost all lymphocytes in human peripheral blood expressed LFA-1 and while the percentage of the LFA-1 positive cells was not modified during the course of the HIV-1 infection in both adults and children, our results showed an increase of the LFA-1 expression on selected peripheral blood mononuclear cell subsets. Some LFA-1-labeled functional peripheral blood mononuclear cell subsets such as the CD16, CD14, CD3, and CD8 lymphocyte subpopulations expressed higher levels of the LFA-1 molecule during the HIV-1 infection. The LFA-1 dim cell subsets (CD4 cells) and the LFA-1 low cell subpopulation (CD19 lymphocytes) were not affected by the HIV-1 infection. Moreover, in the CD8 and CD3 cell subsets displaying a heterogeneous LFA-1 expression (dim and bright), we also observed a decrease of the LFA-1 dim/LFA-1 bright cell ratio.
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PMID:Leukocyte function-associated antigen-1 expression on peripheral blood mononuclear cell subsets in HIV-1 seropositive patients. 214 25

The activity of both cytotoxic T lymphocyte (CTL) and natural killer (NK) cells were measured cross-sectionally in 43 subjects seropositive for HIV, in 27 HIV- blood donors and in 24 HIV- persons from the Outpatients Clinic for sexually transmitted diseases. CTL activity was evaluated using the HL-60 cells coated with OKT3 as the targets and freshly separated peripheral blood lymphocytes as the effectors. In 20 out of 43 HIV+ subjects, CTL activity was significantly enhanced in comparison to the HIV- subjects. This lytic activity correlated positively with the percentages of CD3+ HLA-DR+, of CD8+ CR3- and of CD57+ CD16- lymphocytes, and was greatly reduced after elimination of CD8+, of HLA-DR+ or of CD57+ cells. The median CTL activity seemed to increase from CDC group II to CDC group IV (Centers for Disease Control classification), but to return back to control levels in those patients with a history of opportunistic infections. NK function in HIV+ subjects was not significantly different from that in the blood donors. In seropositive patients, NK activity correlated positively with the percentages of both CD16+ CD57+ and of CD8+ CR3+ cells and was strongly diminished after elimination of CD16+ or of CD57+ cells. There was no significant change in NK function according to the clinical stage. The data show that circulating CD8+ HLA-DR+ CD57+ T cells in HIV+ subjects are activated cytotoxic T cells and point to progressive (over) activation of this T cell compartment until the onset of opportunistic infections.
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PMID:Evidence for circulating activated cytotoxic T cells in HIV-infected subjects before the onset of opportunistic infections. 220 94


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