Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The capacity of human immunodeficiency virus (HIV) antibody-positive sera from homosexually active men without acquired immune deficiency syndrome to lyse the HIV-infected T cell lines MOLT-4f and CCRF-CEM (CEM) in cooperation with lymphocytes from normal donors was investigated. Twenty-seven HIV antibody-positive sera, most of which enhanced the killing of HIV-infected MOLT-4f and CEM target cells by normal mononuclear cells were studied in detail. HIV antibody-positive sera resulted in lysis at dilutions as high as 1/10,000. HIV antibody-negative sera did not augment lysis of infected target cells. In addition, lysis of uninfected targets was not enhanced in the presence of HIV antibody-positive sera. Because fractionation of the HIV antibody-positive sera on a protein A affinity column resulted in recovery of the activity from the IgG fraction, the extra cytotoxic activity mediated by nonimmune cells in the presence of immune sera appears to be antibody-dependent. Furthermore, the cytotoxic effector cells were in the nonrosetting fraction of lymphocytes and expressed Leu-11 (cluster designation (CD)15) antigens, which is characteristic of cells participating in antibody-dependent cellular cytotoxicity reactions. The antibody specificity of the sera, determined by radioimmunoprecipitation, provides evidence that antibody-dependent cellular cytotoxicity can occur even when there are no detectable antibodies directed against gag proteins. Sera which lacked detectable antibodies to the envelope protein gp120 by radioimmunoprecipitation did not mediate antibody-dependent cellular cytotoxicity.
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PMID:Antibodies to human immunodeficiency virus in human sera induce cell-mediated lysis of human immunodeficiency virus-infected cells. 282 Nov 15

The destruction of proliferating lymphoid cells within germinal centers with subsequent replacement by histiocytoid cells has been described in infants and children dying of viral and bacterial infections. The etiology and significance of "epithelioid germinal centers" (EGCs) are unknown. The cells implicated in forming EGCs have included histiocytes and dendritic reticulum cells. We have studied four children at autopsy who died at ages ranging from 10 months to 7 years. Three contracted fatal infections, one with fulminant meningococcemia, one with bacterial sepsis, and one with viral hepatitis. The fourth child contracted viral pneumonitis and died of acetaminophen toxicity. Epithelioid germinal centers were found in numerous lymphoid organs (spleen, lymph nodes, and Peyer's patches) in all four cases. Avidin-biotin complex immunohistochemical analysis performed on formalin-fixed splenic tissue from the first three cases and snap-frozen splenic tissue from the second case revealed an absence of B cells in the follicular centers. The mantle zones surrounding follicles were thin but intact. The histiocytoid cells expanding the germinal centers were positive for S100 and R4/23 (dendritic reticulum cells) and negative for numerous histiocyte markers (alpha 1-antitrypsin, alpha 1-antichymotrypsin, and lysozyme). Increased numbers of killer cells (Leu-7) were present within the affected germinal centers in the three cases in which material was available for immunohistochemical studies. Overwhelming infections in these patients seem to result in anomalous natural killer cell activation resulting in localized nonselective destruction of follicular centers similar to anomalous natural killer cell activity reported to occur in fatal infectious mononucleosis. This may lead to an acquired immunodeficiency that precludes long-term survival in affected patients.
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PMID:Epithelioid germinal centers in overwhelming childhood infections. The aftermath of nonspecific destruction of follicular B cells by natural killer cells. 284 41

In 18 patients with Hodgkin's disease (HD) in long-lasting remission (more than 5 years), the distribution of circulating T-lymphocytes was analyzed using a series of monoclonal antibodies (OKT3, T4, T8, Leu-7, Leu-11 and T10) and correlated with cell function (helper capacity in a pokeweed mitogen system and natural killer (NK) activity). A reduced proportion of OKT4 (helper/inducer)-positive cells associated with a normal absolute number was consistently accompanied by a significant increase (p less than 0.005) in the proportion and absolute number of OKT8 (suppressor/cytotoxic)-positive cells. The OKT4-positive cells, despite their moderate percentage reduction, showed normal helper activity. A more extensive characterization of the lymphoid population in these patients documented a preserved cytotoxic function in a 51Cr release assay and increased proportion of cells expressing NK-associated antigens (Leu-7, Leu-11, OKT10) with a high number of cells coexpressing OKT8 and Leu-7. It is suggested that in patients with Hodgkin's disease in long-lasting remission no laboratory (or clinical) evidence of cellular immunodeficiency can be documented.
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PMID:Normal T-lymphocyte function in patients with Hodgkin's disease in long-lasting remission. 293 89

Fifteen patients and their respective bone marrow donors were entered in this study 1 to 5 yr after allogeneic bone marrow transplantation. Peripheral blood E rosetting (T) cells were analyzed for their phenotypic characteristics as well as for their ability to regulate Ig synthesis in the in vitro PWM system. A close relationship was found between a high proportion of T8+/HNK-1+ cells and/or T8+/HLA-DR+ cells and a strong (greater than or equal to 50%) inhibition of the antibody response. It was noteworthy that even the patients without suppressor activity had high proportions of such cells when compared with normal marrow donors. Moreover, the suppression occurred irrespective of the presence or absence of chronic GVHD. Through negative selection experiments (with MAb and complement) and through immunofluorescence cell sorting, it was shown that the suppressor cells expressed the T8+, HNK-1+, HLA-DR- phenotype. They did not carry the Leu-11, NKH1A, or NKH2 determinants, which are expressed on mature functional NK cells. When examined by electron microscopy, they exhibited a morphology of resting agranular lymphocytes. The significant increase of these suppressor cells among the BMT patients was not correlated with clinical syndromes such as chronic GVHD or opportunistic viral infections, which argues against the notion of in vivo profound immunodeficiency coexisting with these cells.
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PMID:Persistence of T8+/HNK-1+ suppressor lymphocytes in the blood of long-term surviving patients after allogeneic bone marrow transplantation. 294 51

Patients with myeloma have a depressed capacity to respond to antigenic challenge. Studies in this laboratory have previously described an unclassified lymphoid cell which binds human erythrocytes coated with human immunoglobulin G (IgG) anti-D antibody (EA) as important in the inhibition of Ig synthesis in myeloma patients. Using monoclonal antibodies, two-color fluorescence studies, and flow cytometry, we characterized this EA cell as a Leu-1+ (cluster designation (CD) 5), Leu-12+ (CD 19), Leu-16+ (CD 20), B2+ (CD 21), Leu-14+ (CD 22), and HLA-DR+ B cell. The cell was negative for antibodies to Leu-2 (CD 8), Leu-3 (CD 4), Leu-4 (CD 3), Leu-5 (CD 2), Leu-7, Leu-8, Leu-11 (CD 16), Leu-M1 (CD 15), Leu-M3, and CALLA (CD 10). This profile is consistent with a Leu-1+ B cell and excludes a T cell, natural killer cell, and monocyte. Comparison of the relative role of these cells to the role of monocytes in the suppression of pokeweed mitogen-stimulated Ig synthesis was determined in serial studies on 19 myeloma patients. The mean (+/- SEM) percentage of inhibition of Ig synthesis by monocytes from stage I myeloma patients was 14 +/- 2.2%, from stage II patients was 37 +/- 3.5%, and from stage III patients was 51 +/- 4.7%. Inhibition of Ig synthesis by Leu-1+ EA cells was 46 +/- 1.5%, 48 +/- 1.6%, and 43 +/- 3.7% in stage I, II, and III patients, respectively. Immunosuppressive B cells are an important component of inhibition of Ig synthesis in the immunodeficiency of myeloma.
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PMID:Multiple myeloma: an immunologic profile. IV. The EA rosette-forming cell is a Leu-1 positive immunoregulatory B cell. 295 12

As part of a larger study to characterize immune alterations in blood donors seropositive for human immunodeficiency virus (HIV), we measured subsets of CD4 (T helper/inducer) and CD8 (T suppressor/cytotoxic) cells by 2-color cytofluorometry. Alterations observed in asymptomatic seropositive donors (ASP) included: 1) decreased mean levels of Leu 8+ CD4 cells, although the proportion of Leu 8+ cells within the CD4 population was unchanged; 2) a selective increase in Leu 8- CD8 and Leu 18- CD8 cell levels; and 3) increased levels of both CD8 subsets defined by Leu 7, Leu 17, or HLA-DR expression. Alterations observed in symptomatic seropositive donors (SSP) were: 1) a further decrease in Leu 8+ CD4 cell levels, with a decrease in the proportion of Leu 8+ CD4 cells; 2) decreased levels of both Leu 18- and Leu 18+ CD4 subsets; 3) selective increases in Leu 8- and Leu 18- CD8 cell levels; and 4) increases in Leu 7+ CD8, Leu 17+ CD8, and HLA-DR+ CD8 subsets but not the reciprocal negative CD8 subsets. Thus, changes merely reflective of HIV infection included decreased levels of Leu 8+ CD4 cells and increased levels of Leu 8- CD8, Leu 18- CD8, Leu 7+ CD8, Leu 17+ CD8, and HLA-DR+ CD8 cells. Development of symptoms were associated with a further, preferential loss of Leu 8+ CD4 cells, proportional losses of both CD4 subsets defined by Leu 18 expression, and a return to normal levels of Leu 7- CD8, Leu 17- CD8, and HLA-DR- CD8 cells.
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PMID:CD4 and CD8 subsets defined by dual-color cytofluorometry which distinguish symptomatic from asymptomatic blood donors seropositive for human immunodeficiency virus. 296 80

The major histocompatibility complex (MHC) class II deficiency syndrome is a rare immunodeficiency disease associated with defective expression of class II MHC antigens. We have examined the consequences of this defect for the differentiation and functional capabilities of immunoregulatory T-cell subpopulations in an affected patient. Although the number of circulating T cells was normal, there was a striking reduction in the number of CD4+ T cells. Furthermore, purified CD4+ cells from the patient were unable to provide help for antibody secretion. This defect in helper function appeared to be due to the abnormal differentiation of the few CD4+ cells present, virtually all of which expressed the CD4+HB11+ phenotype characteristic of immature "virgin" T cells. Abnormal development of immunoregulatory CD8+ T cells was also observed. Although increased numbers of CD8+ T cells were present, virtually none had phenotypic properties of suppressor cells (i.e., CD3+/CD8+/9.3- granular lymphocytes that coexpress the Leu-15 or Leu-7 antigens), and purified CD8+ cells from the patient had no suppressor activity. Thus, the absence of class II MHC antigens profoundly disrupts the development of immunoregulatory T cells. We propose that these effects occur by the following mechanisms: (1) the absence of intrathymic class II antigens results in deficient production of CD4+ cells, (2) the CD4+ cells that do emerge from the thymus do not undergo postthymic maturation into CD4+HB11- cells with helper capabilities, and (3) the absence of CD4+HB11- effector cells results in abortive development of suppressor cells involved in feedback suppression.
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PMID:Abnormal differentiation of immunoregulatory T-lymphocyte subpopulations in the major histocompatibility complex (MHC) class II antigen deficiency syndrome. 297 72

The expression of phenotypic markers on T and B lymphocytes in long-term human immunodeficiency virus type 1 (HIV-1) seropositive, antigen negative patients, in seropositive, antigen positive individuals without AIDS and in seronegative intravenous drug abusers was examined by two colour flow cytometry. Seropositive, antigen positive patients showed decreased CD4+ lymphocyte numbers, causing lower CD4/CD8 ratios when compared to seropositive, antigen negative subjects. While CD4 CDw29+ (4B4) lymphocytes are selectively reduced in seropositive, antigen negative individuals, both CD4 CDw29+ and CD4 CD45R+ (2H4) lymphocytes are decreased when antigenaemia is present. An increased percentage of CD3 HLA DR+ activated T lymphocytes and of CD20+ (B1) Leu 8 negative activated B cells was seen in HIV-1 seropositive antigen positive patients. These results demonstrate that, in long-term seropositive individuals, antigenaemia is associated with peculiar phenotypic changes of lymphocyte subsets.
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PMID:Immunologic abnormalities related to antigenaemia during HIV-1 infection. 297 19

Subsets of Leu-2+/T8+ cytotoxic/suppressor T lymphocytes were isolated by using various methods of purification and were investigated for expression of ecto-5' nucleotidase (5'NT) enzyme activity by radiochemical, cytochemical, and ultrastructural techniques. By using both the radiochemical and the cytochemical methods. T4-OKM1- cells displayed higher 5'NT activity in comparison with the entire T4- subpopulation. Analyses of the subpopulations of T4- (and predominantly Leu-2+) cells defined by the Leu-15 or Lyt-1 (9.3) monoclonal antibodies demonstrated that T4-Leu-15- and T4-Lyt-1+ cells displayed high 5'NT activity, whereas virtually no activity was present in T4-Leu-15+ and T4-Lyt-1-cells. At the ultrastructural level, the 5'NT reaction product was detected on the plasma membrane of a proportion of nongranular Leu-2+/T8+ lymphocytes, but no activity was found on cells with a granular lymphocyte (GL) morphology. 5'NT activity was also analyzed in peripheral blood mononuclear cells from one patient with expanded numbers of GL and two patients with GL leukemia. The enzymatic activity was significantly lower in these patients than in normal controls. This study provides new cytochemical evidence demonstrating the heterogeneity of Leu-2+/T8+ cells, and indicates that the population with the suppressor phenotype and function (Leu-15+/Lyt-1-, GL morphology) displays low or absent 5'NT activity, whereas the population composed of cytotoxic cell precursors (Leu-15-/Lyt-1+, nongranular morphology) has high 5'NT activity. Implications of these data for the interpretation of low 5'NT activity described in several immunodeficiency states and lymphoproliferative disorders are discussed.
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PMID:Differential expression of ecto-5' nucleotidase activity by functionally and phenotypically distinct subpopulations of human Leu-2+/T8+ lymphocytes. 301 91

A patient with multiple infections whose serum had antibodies to a human immunodeficiency virus (HIV) developed a T-cell lymphoblastic lymphoma (T11+, Leu-1+, Leu-3a+, TdT+, B1-, common ALL-). Antibodies to human T-lymphotropic virus-I (HTLV-I) were absent. T-cell leukemia-lymphoma may be associated with HIV infection.
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PMID:Human immunodeficiency virus-associated T-cell lymphoblastic lymphoma in AIDS. 304 Feb 18


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