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)

We have studied T- and B-cell responses to antigens of Candida albicans in 18 patients suffering from chronic mucocutaneous candidiasis. We have shown that in vitro production of antibody to one of these antigens, mannan, was absent during the active phase of the disease and that this absence was consequent to the activation of specific CD8(+) and CD8(-) suppressor T lymphocytes. Such activation was also observed when control T lymphocytes were incubated in the presence of monocytes and a high concentration of mannan. This suppressive effect was specific to antigens of Candida albicans, was radiosensitive, and was not consequent to the secretion of prostaglandin E2. It appeared as well that the induction of these suppressor T cells was HLA-DQ restricted. The suppressor T-cell activity induced by antigens of Candida albicans in vitro is thus comparable to the suppressor T-cell activity observed in vivo in patients affected with chronic mucocutaneous candidiasis. Defective handling of mannan by monocytes could result in the accumulation of mannan, resulting in the activation of specific T suppressor cells and in the consequent cellular immunodeficiency specific to Candida albicans. Successful treatment of the candidiasis resulted in complete correction of the immune abnormalities.
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PMID:Mannan-specific and mannan-induced T-cell suppressive activity in patients with chronic mucocutaneous candidiasis. 295 95

Oral hairy leukoplakia (HL) is a recently described manifestation of human immunodeficiency virus (HIV) infection in which Epstein-Barr virus (EBV) has been shown to replicate. To seek evidence for a local defect in mucosal immunity, we assessed the presence of epithelial Langerhans cells (LC) in these lesions and in autologous nonlesional mucosa. We used monoclonal antibodies against HLA-DR, HLA-DQ, and T6 antigens to identify LC in biopsy specimens of HL from 23 homosexual men. In all lesion specimens, LC either were not detected or were present only in greatly reduced numbers with at least 1 of the antibodies. In nonlesional oral mucosa from the same patients, LC were detected with all 3 antibodies in 11/12 specimens (92%) and were found in approximately normal numbers with at least 1 antibody. There was close correlation between the absence of LC and positive staining for EBV, human papillomavirus antigens, and candidal hyphae in the epithelium. We conclude that LC are absent or greatly reduced in the lesions of HL. Absence of normal LC function may be important in the pathogenesis of HL and may reflect an event in the pathogenesis of other features of the acquired immune deficiency syndrome.
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PMID:Absence of Langerhans cells in oral hairy leukoplakia, an AIDS-associated lesion. 311 Mar

The antigenic phenotype of human villous stromal macrophages (M phi s) from first and third trimester placentas was analyzed using a large number of monoclonal antibodies (MAbs) to monocyte (Mo)/M phi-associated cell membrane determinants. The purpose of this study was to investigate M phi phenotypic heterogeneity to create a database for the correlation of M phi phenotype with specific immunologic functions. The results showed that villous stromal mononuclear cells express many cell surface antigens found on Mo and M phi s and that they are morphologically diverse, ranging in appearance from classic Hofbauer cells to spindle-shaped cells with long cytoplasmic processes. Villous stromal M phi s were the numerically dominant cell type in this structure and exhibited some major phenotypic differences from M phi s in other tissues. Comparison of first- and third-trimester placentas revealed variation in antigen expression with increasing gestational age, in particular of class II major histocompatibility complex (MHC) determinants: HLA-DR and HLA-DP antigen density was low on first-trimester villous M phi s and much higher on third-trimester M phi s while HLA-DQ was undetectable in the first trimester but present on cells in third trimester placentas. The CD1 (T6) antigen, found on Langerhans (LH) cells and cortical thymocytes, was detected on villous M phi s by two thirds of the MAbs directed against different epitopes on this determinant. Furthermore, comparison with similar studies of lymphoid tissues showed that villous M phi s and dendritic cells share the expression of a number of other cell surface antigens. Finally, it was shown that M phi s in first- and third-trimester villi exhibit strong reactivity with MAbs (Leu 3a,b) to the CD4 antigen that serves as the receptor for the human immunodeficiency virus (HIV), suggesting that these cells may be a portal of entry or reservoir for this virus in the fetuses of pregnant, HIV+ women.
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PMID:The phenotype of human placental macrophages and its variation with gestational age. 326 59

The CD4 molecule, which is known to play an important role in the susceptibility of T lymphocytes to infection by the human immunodeficiency virus (HIV), is also expressed in small amounts on the surface of monocytes. Since monocytes can also be infected by the virus, we investigated peripheral blood monocytes of patients with the acquired immunodeficiency syndrome (AIDS), AIDS-related complex (ARC), and HIV seropositive and seronegative haemophiliacs without symptoms for the expression of the CD4 molecule and for other functionally important surface molecules such as CD11 (C3bi receptor), transferrin receptor, Fc receptor, and the three major histocompatibility complex (MHC) class II antigens HLA-DP, HLA-DR, and HLA-DQ. With immunofluorescence staining and flow cytometry no difference was found between patients and controls for the expression of the CD4 molecule and for the other antigens as assessed by the percentage of positive staining and the specific fluorescence intensity in a double marker analysis. The percentage of CD4+ monocytes was found to be 59.2 +/- 14.4% for 16 patients with AIDS and 52.9 +/- 12.8% for 12 healthy controls. Similar to our results on phenotype, we found no significant difference with respect to the production of tumour necrosis factor (TNF), in that monocytes of AIDS and ARC patients showed an increase in TNF secretion after stimulation with LPS comparable to controls.
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PMID:Monocyte phenotype and function in patients with the acquired immunodeficiency syndrome (AIDS) and AIDS-related disorders. 368 87

We postulated that changes in the cell surface display of molecules that facilitate cell-cell and cell-matrix adhesions may reflect the changing immunosurveillance capacity of blood monocytes during progression of human immunodeficiency virus (HIV) infections. In Centers for Disease Control (CDC) stage A patients, whose monocytes' ability to phagocytose bacteria and generate reactive oxygen intermediates is often increased, the frequency of monocytes expressing CD49d, HLA-DP, HLA-DQ, and an activation epitope of CD11a/CD18 was increased and monocyte transendothelial migration was unimpaired. In CDC stage B/C patients, whose monocytes' ability to phagocytose bacteria and migrate across confluent endothelial monolayers was diminished, surface expression of CD49e and CD62L and the percentage of monocytes expressing CD18, CD11a, CD29, CD49e, CD54, CD58, CD31, and HLA-I were significantly decreased. Incubating normal donor monocytes with immune complexes in vitro reproduced the phenotypic and functional abnormalities seen in stage B/C patients. By contrast, in vitro stimulation with subcellular particulates released by apoptotic lymphocytes reproduced changes seen in stage A patients' monocytes. Although circulating monocytes appear to be activated at all stages, these data suggest that the high levels of circulating immune complexes, found predominantly in the later stages of HIV infection, may be particularly instrumental in reducing the monocyte's capacity to maintain surveillance against infection.
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PMID:Phenotypic and functional changes in peripheral blood monocytes during progression of human immunodeficiency virus infection. Effects of soluble immune complexes, cytokines, subcellular particulates from apoptotic cells, and HIV-1-encoded proteins on monocytes phagocytic function, oxidative burst, transendothelial migration, and cell surface phenotype. 770 78

Swiss mice were injected intraperitoneally with uninfected or human immunodeficiency virus type 1 (HIV-1) infected human U937 cells. At 6 days, no residual human cells were detected in mouse tissues as determined by PCR analysis of DNAs from injected mice using primers and probes for the human HLA-DQ alpha gene. At 6 to 12 months, approximately 60% of the HIV-1-infected mice had antibodies to HIV-1 gp 120 and gp41 proteins. Fifteen percent of the animals showed evidence of HIV-1 infection as determined by PCR analyses of DNA from peripheral blood leukocytes and by in situ hybridization for detection of HIV-1 mRNA in peritoneal cells. In this set of experiments, spleen cells from mice sacrificed at different times after injection were cultured for 48 h in the presence or absence of mitogens [i.e.: concanavalin (Con A) or anti-CD3 antibody] and then tested for lymphocyte proliferation. At 10 to 12 months, splenocytes from approximately 80% of Swiss mice injected with HIV-1-infected U937 cells exhibited a marked defect in their proliferative response to Con A or anti-CD3 antibody as compared with spleen cells from both uninjected or U937 cell-injected mice. Similar results were obtained at 12 months in C3H/HeJ mice. Non-responding spleen cells from HIV-1-injected Swiss mice did not proliferate in response to anti-CD3 antibody even in the presence of co-stimulatory molecules such as phorbol myristate acetate or anti-CD28 antibody. Splenocytes from these mice also exhibited an impaired capacity to produce interferon-gamma and interleukin-4 after mitogen stimulation. No T cell defects were observed in control-injected mice. Immunofluorescence analyses revealed a significant decrease in the percentage of both CD4+ and CD8+ spleen cells in HIV-1-injected mice. These data indicate that immunocompetent mice can be used to investigate some HIV-1-related immune dysfunctions in vivo.
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PMID:Defective response to T cell mitogens in mice injected with human immunodeficiency virus type 1-infected U937 cells. 793 Nov 68

Alveolar macrophages (AMs) harvested from 32 HIV-infected patients with respiratory problems (opportunistic pulmonary infections, n = 12; other lung disease, n = 20) and 13 healthy controls were stained with a panel of 15 monoclonal antibodies directed against surface antigens implicated in cell function. Antigen expression was quantified by flow cytometry and expressed as relative linear median fluorescence intensity (RLMFI). On AMs of patients, as compared with controls, there was a significant enhancement of HLA DP (12.1 +/- 1.5 vs 6.5 +/- 0.9, p = 0.01, M +/- SEM, RLMFI units), CD11b (3.4 +/- 0.5 vs 1.7 +/- 0.4, p = 0.014), CD11c (8.9 +/- 1.0 vs 4.8 +/- 0.8, p = 0.0046), CD14 (2.1 +/- 0.3 vs 1.0 +/- 0.2, p = 0.0009), and CD33 (1.7 +/- 0.1 vs 1.0 +/- 0.2, p = 0.0093). No significant differences could be established for HLA-DR (36.9 +/- 5.8 vs 30.9 +/- 7.5, NS), HLA-DQ (3.4 +/- 0.3 vs 3.1 +/- 0.6, NS), CD54 (1.9 +/- 0.3 vs 1.2 +/- 0.1, NS), CD13 (2.5 +/- 0.6 vs 1.5 +/- 0.3, NS), CD36 (1.4 +/- 0.2 vs 0.9 +/- 0.3, NS), CD71 (10.3 +/- 1.9 vs 8.9 +/- 1.8, NS), CD25 (0.8 +/- 0.0 vs 0.9 +/- 0.1, NS), 27E10 (1.1 +/- 0.1 vs 0.8 +/- 0.3, NS), RM3/1 (1.9 +/- 0.4 vs 1.5 +/- 0.4, NS), and CD4 (1.5 +/- 0.3 vs 1.0 +/- 0.0, NS). The expression of CD14 and CD11b, but not of HLA class II antigens and CD71, was increased in the smaller cell population compared with the larger, thus suggesting monocyte recruitment. The increased expression of HLA-DP, CD11c, CD14, and CD33 on the patients' AMs was independent of smoking habits. The degree of immunodeficiency as indicated by the absolute peripheral CD4 count, the character of HIV-related pulmonary disease, and the prophylactic use of pentamidine or zidovudine did not significantly modify the antigen expression pattern. It is concluded that HIV infection may lead, most probably indirectly, to enhanced expression of surface antigens by local upregulation and/or recruitment of monocytes from the peripheral circulation. The functional significance of enhanced marker expression requires further clarification.
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PMID:Expression of surface markers on alveolar macrophages from symptomatic patients with HIV infection as detected by flow cytometry. 818 14

Photochemical decontamination (PCD) of platelet concentrates, with adequate preservation of platelet function, has been shown using 8-methoxypsoralen (8-MOP) and long wavelength UV light (UVA). To further evaluate this technique, models for the inactivation of pathogenic human cell-associated viruses and integrated proviral sequences are required. We have assessed the ability of the PCD technique to inactivate cell-associated human immunodeficiency virus 1 (HIV-1) in platelet concentrates. We correlated PCD inhibition of HIV-1 infectivity with 8-MOP-DNA adduct formation in contaminating nucleated cells, and measured the inhibition of polymerase chain reaction (PCR)-mediated amplification of cellular DNA sequences as a surrogate for inactivation of integrated proviral nucleic acid sequences. After PCD treatment (8-MOP 300 micrograms/mL, UVA 17 mW/cm2) for 60 minutes, 0.5 x 10(6) plaque-forming units (PFU)/mL of cell-associated HIV-1 were inactivated and no virus was detectable by infectivity assay. After 60 minutes of PCD, 15 8-MOP-DNA adducts per 1,000 bp were formed, while in the absence of UVA, no adducts were formed. PCR-mediated amplification of a 242-bp cellular DNA sequence (HLA-DQ-alpha) was inhibited when greater than eight psoralen-DNA adducts per 1,000 bp were present. These studies indicate that high titers of cell-associated HIV-1 in platelet concentrates were inactivated by PCD, and the numbers of 8-MOP-DNA adducts in nucleated cells were sufficient to inhibit amplification of DNA segments that encode for as few as 80 amino acids. Based on the frequency of 8-MOP-DNA adducts, for the 10-kb HIV-1 genome, the probability of an integrated genome without at least one 8-MOP adduct after 60 minutes of PCD was 10(-33).
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PMID:Photochemical inactivation of cell-associated human immunodeficiency virus in platelet concentrates. 832 30

The bare lymphocyte syndrome (BLS) consists of an association between a combined immunodeficiency disease and a significantly reduced expression of either human histocompatibility leukocyte antigens (HLA) class I (HLA-A, -B, -C) or HLA class II (HLA-DP, -DQ, -DR) at the cell surface. BLS type III, the more frequent form of this syndrome, is characterized by impaired expression of both class I and class II antigens on patients' cells, in particular on leukocytes. We describe herein the demonstration that expression of HLA class I molecules was reduced by approximately half on Epstein-Barr virus-transformed B cells (LCL) derived from type III BLS patients. HLA class I mRNA level was also decreased to the same extent. Expression of HLA class I molecules was also very significantly reduced at the surface of these fibroblasts as was mRNA specific for HLA class I. Simultaneously, the expression of HLA-DR molecules on LCL was even more greatly decreased, and the expression of HLA-DQ antigens was virtually abolished. Molecular analysis demonstrated an absence of mRNA for the alpha- and beta-chains of HLA-DQ and HLA-DR in the patients' lymphocytes. In general, such patients present with an association of an absence of expression of HLA class II antigens and a significantly reduced expression of HLA class I antigens. The mechanism of this association is still uncertain.
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PMID:Type III bare lymphocyte syndrome: lack of HLA class II gene expression and reduction in HLA class I gene expression. 895 82

Previously, we have shown that CD4 levels in African Americans infected with human immunodeficiency virus-1 (HIV-1) were lower than those in Caucasians. To determine whether or not HLA type is associated with susceptibility to HIV-1 infection, we demonstrated serologically that HLA-DQ6(1) and HLA-DQ7(3) were associated with HIV-1 infection in both African Americans and Caucasians. The present investigation was designed to demonstrate whether or not HLA-DQB1 alleles were associated with HIV-1 infection or protection from infection within these two ethnic groups. Oligonucleotide typing was employed and results were analyzed by chi 2 with Fisher's exact test to compare HLA-DQ marker frequencies in the regional control population (98 African Americans, 143 Caucasians) to the disease population (n = 52; 30 African Americans and 22 Caucasians). We found a statistically significant increased risk of HIV infection associated with HLA-DQB1*0605 in African Americans, and with HLA-DQB1*0602 in Caucasians. By contrast, HLA-DQB1*0603 was associated with protection in Caucasians.
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PMID:HIV-1 disease association with HLA-DQ antigens in African Americans and Caucasians. 903 30


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