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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human immunodeficiency virus (HIV) infection of brain macrophages and astroglial proliferation are central features of HIV-induced central nervous system (CNS) disorders. These observations suggest that glial cellular interactions participate in disease. In an experimental system to examine this process, we found that cocultures of HIV-infected monocytes and astroglia release high levels of cytokines and arachidonate metabolites leading to neuronotoxicity. HIV-1ADA-infected monocytes cocultured with human glia (astrocytoma, neuroglia, and primary human astrocytes) synthesized tumor necrosis factor (TNF-alpha) and interleukin 1 beta (IL-1 beta) as assayed by coupled reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and biological activity. The cytokine induction was selective, cell specific, and associated with induction of arachidonic acid metabolites. TNF-beta, IL-1 alpha, IL-6, interferon alpha (IFN-alpha), and IFN-gamma were not produced. Leukotriene B4, leukotriene D4, lipoxin A4, and platelet-activating factor were detected in large amounts after high-performance liquid chromatography separation and correlated with cytokine activity. Specific inhibitors of the arachidonic cascade markedly diminished the cytokine response suggesting regulatory relationships between these factors. Cocultures of HIV-infected monocytes and neuroblastoma or endothelial cells, or HIV-infected monocyte fluids, sucrose gradient-concentrated viral particles, and paraformaldehyde-fixed or freeze-thawed HIV-infected monocytes placed onto astroglia failed to induce cytokines and neuronotoxins. This demonstrated that viable monocyte-astroglia interactions were required for the cell reactions. The addition of actinomycin D or cycloheximide to the HIV-infected monocytes before coculture reduced, > 2.5-fold, the levels of TNF-alpha. These results, taken together, suggest that the neuronotoxicity associated with HIV central nervous system disorders is mediated, in part, through cytokines and arachidonic acid metabolites, produced during cell-to-cell interactions between HIV-infected brain macrophages and astrocytes.
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PMID:Cytokines and arachidonic metabolites produced during human immunodeficiency virus (HIV)-infected macrophage-astroglia interactions: implications for the neuropathogenesis of HIV disease. 146 Apr 27

Recombinant human migration inhibitory factor (MIF), isolated through functional expression cloning in COS-1 cells, up-regulates expression of genes encoding HLA-DR and interleukin 1 beta (IL-1 beta) and elaboration of IL-1 beta by human monocyte-derived macrophages. Administration of soluble bovine serum albumin or human immunodeficiency virus 120-kDa glycoprotein (HIV gp120) to mice in the presence of recombinant MIF together with incomplete Freund's adjuvant induced a strong T-cell proliferative response comparable to that of complete Freund's adjuvant. Recombinant MIF also increased antibody production, especially of IgG1 and IgM, in mice. Taken together, these results indicate that recombinant MIF may be useful as an adjuvant in the development of vaccines.
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PMID:Recombinant human migration inhibitory factor has adjuvant activity. 901 81

Cell lines derived from Kaposi sarcoma lesions of patients with AIDS (AIDS-KS cells) produce several cytokines, including an endothelial cell growth factor, interleukin 1 beta, and basic fibroblast growth factor. Since exposure to human immunodeficiency virus increases interleukin 6 (IL-6) production in monocytes and endothelial cells produce IL-6, we examined IL-6 expression and response in AIDS-KS cell lines and IL-6 expression in AIDS Kaposi sarcoma tissue. The AIDS-KS cell lines (N521J and EKS3) secreted large amounts of immunoreactive and biologically active IL-6. We found both IL-6 and IL-6 receptor (IL-6-R) RNA by slot blot hybridization analysis of AIDS-KS cells. The IL-6-R was functional, as [3H]thymidine incorporation by AIDS-KS cells increased significantly after exposure to human recombinant IL-6 (hrIL-6) at greater than 10 units/ml. When AIDS-KS cells (EKS3) were exposed to IL-6 antisense oligonucleotide, cellular proliferation decreased by nearly two-thirds, with a corresponding decrease in the production of IL-6. The decrease from IL-6 antisense in AIDS-KS cell proliferation was reversed by the addition of hrIL-6. We confirmed that AIDS-KS cells produced IL-6 in vivo by preparing RNA and tissue sections from involved and uninvolved skin from a patient with AIDS Kaposi sarcoma. We detected immunoreactive IL-6 in the involved tumor areas and to a lesser extent in the surrounding normal epidermis. Slot blot hybridization showed a great excess of IL-6 and IL-6-R RNA in involved skin compared to uninvolved skin. These results show that both IL-6 and IL-6-R are produced by AIDS-KS cells and that IL-6 is required for optimal AIDS-KS cell proliferation, and they suggest that IL-6 is an autocrine growth factor for AIDS-KS cells.
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PMID:AIDS Kaposi sarcoma-derived cells produce and respond to interleukin 6. 169 29

We have investigated the roles of cytokines in the modulation of human immunodeficiency virus (HIV) production in chronically infected U937 cells upon in vitro differentiation by hydroxyvitamin D3. HIV-infected U937 cells exhibited markedly lower levels of CD4 and HLA-DR antigens than uninfected cells did. Vitamin D3 induced a time-dependent macrophagelike differentiation, as determined by monitoring the expression of some surface antigens by means of the monoclonal antibodies OKM1, OKM5, OKM13, OKM14, OKT4, anti-HLA-DR, TecMG2, TecMG3, LeuM3, LeuM1, anti-HLA-DP, and anti-HLA-DQ. Treatment with hydroxyvitamin D3 resulted in a marked increase in HIV production compared with control cultures. Interleukin 1 beta (IL-1 beta) and tumor necrosis factor alpha (TNF-alpha) were detected in the culture media, whereas interferon (IFN) was not generally found. Using the polymerase chain reaction technique, we found HIV-infected U937 cells to express detectable levels of mRNAs for alpha interferon (IFN-alpha), IFN-beta, TNF-alpha, and IL-1 beta. The addition of TNF resulted in a marked increase of HIV production, whereas IL-1 beta was ineffective. In contrast, both IFN-alpha and IFN-beta exerted some inhibitory effect on HIV production, which was more marked in vitamin D3-treated cultures than in untreated cultures. HIV production was significantly increased by antibodies to IFN-alpha in both untreated and vitamin D3-treated cultures. Anti-IFN-beta antibody increased HIV production only in vitamin D3-treated cells. In contrast, anti-TNF-alpha antibodies markedly decreased HIV production in both control and differentiating U937 cells. Vitamin D3 treatment resulted in a higher expression of TNF receptors in differentiating cells than in control HIV-infected cells. These data demonstrate a strong correlation between HIV production and macrophagelike differentiation in chronically infected U937 cells and suggest that endogenous IFN and TNF exert opposite effects in the regulation of virus production in both undifferentiated and vitamin D3-treated cell cultures.
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PMID:Increased human immunodeficiency virus (HIV) expression in chronically infected U937 cells upon in vitro differentiation by hydroxyvitamin D3: roles of interferon and tumor necrosis factor in regulation of HIV production. 170 Aug 29

We show here for the first time that actin, troponin C, Alzheimer amyloid precursor protein (AAP), and pro-interleukin 1 beta (pro-IL-1 beta), are substrates of the protease encoded by the human immunodeficiency virus (HIV) type-1. As has been seen in other non-viral protein substrates of the HIV protease, the presence of Glu residues in the P2' position appears to play an important role in substrate recognition. Three of the four bonds cleaved in actin, two of the three in troponin C, and all of the bonds hydrolyzed in AAP and pro-IL-1 beta have a P2' Glu residue. In fact, Glu residues are accommodated in all positions from P4 to P4' surrounding the scissile bond in substrates of the HIV proteases, and as many as 4 adjacent Glu residues were seen in one of the bonds cleaved in AAP. This study of non-viral protein substrates has also revealed unexpected amino acids such as Gly, Arg, and Glu in the scissile bond itself rather than the more conventional hydrophobic amino acids. The HIV-2 protease hydrolyzed actin in a manner similar to that of the HIV-1 enzyme, but its cleavage of troponin C was distinct in that it split a bond adjacent to a triplet of Glu residues in P2, P3, and P4 that was refractory to the HIV-1 enzyme. Documentation of cleavage sites in the several important cellular proteins noted above has extended our understanding of the features in a substrate that are recognized by these multi sub-site proteases of retroviral maturation. Moreover, the present work adds to an accumulating body of evidence which demonstrates that these enzymes can damage crucial structural and regulatory cellular proteins if ever their activity is expressed outside the viral particle itself.
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PMID:Actin, troponin C, Alzheimer amyloid precursor protein and pro-interleukin 1 beta as substrates of the protease from human immunodeficiency virus. 190 79

Macrophages, unlike CD4+ T cells, can be productively infected by human immunodeficiency virus (HIV) without prior cellular activation. Cytopathic infection ensues without the induction of tumor necrosis factor alpha (TNF alpha), interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), or tissue factor genes. In detailed studies on TNF alpha, HIV infection did not affect the regulation of TNF alpha in response to bacterial lipopolysaccharide. In an effort to examine the interferon responsiveness of HIV-infected macrophages, the cells were challenged with vesicular stomatitis virus (VSV) with or without interferon pretreatment. Surprisingly, HIV-infected macrophages were completely resistant to VSV-induced lysis even in the absence of interferon; however, no interferon was detected in the supernatants of these infected cells. The resistance of HIV-infected macrophages to superinfection with VSV indicates a previously undescribed effect of HIV upon macrophage cellular metabolism.
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PMID:Characterization of a macrophage-tropic HIV strain that does not alter macrophage cytokine production yet protects macrophages from superinfection by vesicular stomatitis virus. 217 98

Interferon alpha (IFN-alpha) induces significant antiretroviral activities that affect the ability of human immunodeficiency virus (HIV) to infect and replicate in its principal target cells, CD4+ T cells and macrophages. A major endogenous source of IFN-alpha during any infection is the macrophage. Thus, macrophages have the potential to produce both IFN-alpha and HIV. In this study, we examined the production of IFN-alpha and other cytokines by macrophage colony-stimulating factor (M-CSF)-treated cultured monocytes during HIV infection. Tumor necrosis factor alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), IL-6, IFN-omega, or IFN-beta were not detected nor was the mRNA expressed in either uninfected or HIV-infected monocytes. However, both uninfected and HIV-infected monocytes produced high levels of each of these cytokines after treatment with synthetic double-stranded RNA [poly(I).poly(C)]. Uninfected monocytes also produced high levels of IFN-alpha after treatment with poly(I).poly(C), Newcastle disease virus, or herpes simplex virus. In marked contrast to the preceding observations, HIV-infected monocytes produced little or no IFN-alpha before or after treatment with any of these agents. The absence of detectable IFN-alpha activity and mRNA in poly(I).poly(C)-treated HIV-infected monocytes was coincident with high levels of 2',5' oligoadenylate synthetase and complete ablation of HIV gene expression. The antiviral activity induced by poly(I).poly(C) may be a direct effect of this synthetic double-stranded RNA or secondary to the low levels of IFN-beta and IFN-omega produced by infected cells. The markedly diminished capacity of HIV-infected monocytes to produce IFN-alpha may reflect a specific adaptive mechanism of virus to alter basic microbicidal functions of this cell. The inevitable result of this HIV-induced cytokine dysregulation is virus replication and persistence in mononuclear phagocytes.
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PMID:A selective defect of interferon alpha production in human immunodeficiency virus-infected monocytes. 198 24

Mononuclear phagocyte-derived cytokines are important regulators of haemopoiesis in inflammatory conditions. By means of radioimmunoassay we measured the levels of two cytokines, tumour necrosis factor-alpha and interleukin 1 beta in sera from subjects infected with human immunodeficiency virus, and related the levels to the presence and severity of haematological abnormalities. The levels of tumour necrosis factor-alpha were significantly higher in patients with anaemia (142 +/- 17 (SE) pg ml-1), lymphopenia (107 +/- 20 pg ml-1) or both (137 +/- 21 pg ml-1) than in individuals without anaemia (18 +/- 5 pg ml-1; P less than 0.001), without lymphopenia (16 +/- 7 pg ml-1; P less than 0.001) or without either disorder (19 +/- 7 pg ml-1; P less than 0.001). A strong negative correlation was found between tumour necrosis factor-alpha and haemoglobin values (r = -0.83, P less than 0.001) and absolute lymphocyte count (r = -0.66, P less than 0.001) in human immunodeficiency virus infection. The changes in the levels of serum interleukin 1 beta were less pronounced but followed the same general trend as the changes in tumour necrosis factor-alpha. The results show that the production of mononuclear phagocyte-derived cytokines is enhanced in acquired immunodeficiency syndrome, and that the levels of these factors are correlated with the presence of certain haematological abnormalities.
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PMID:Correlation of serum cytokine levels with haematological abnormalities in human immunodeficiency virus infection. 232 81

We examined the role of endogenously produced interleukin 1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) in lectin-induced nonspecific suppressor activity in vitro. The cultures consisted of highly purified T lymphocytes, autologous monocytes and phytohemagglutinin (PHA). Kinetic studies revealed peak levels for both TNF-alpha and IL-1 beta production 4 hr after initiation of cultures which then declined and reached minimal levels on day 3. At this time point maximal levels of interleukin-2 (IL-2) were detected which declined sharply 24 hr later. The decline in cytokine levels in culture supernatants was most probably due to their consumption by the mononuclear cells which were found to express specific receptors for IL-1 beta, (IL-1 beta R), TNF-alpha (TNF-alpha R) and IL-2 (IL-2R) after 3- and 6-days of culture. After their first cycle of production and consumption both monokines were reproduced and the events followed the same patterns as for the first cycle: both monokines were first produced and at the time point of their consumption, IL-2 production reached maximal levels. The requirement for IL-1 beta and TNF-alpha in both IL-2 production and generation of suppressor activity was shown by three different approaches which included (a) blocking of HLA-DR molecules on monocytes which prevented monokine consumption during the early stages of culture, (b) blocking of HLA-A,B,C molecules on monocytes which prevented monokine consumption and IL-2 production late in culture, and (c) neutralization of monokine activity late in culture which resulted in highly reduced IL-2 production. T lymphocytes harvested from such cultures exhibited diminished suppressor activity. Our data suggest that the generation of nonspecific suppressor cell activity in vitro represents a complex system that requires cell interactions via self-major histocompatibility complex (MHC) antigen recognition and two cycles of cytokine production, where IL-1 beta and TNF-alpha production and consumption is a prerequisite for IL-2 production. Since lectin-induced nonspecific suppressor activity in vitro is deficient in certain autoimmune disorders the data presented herein might help in understanding the cellular basis for this immunodeficiency.
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PMID:On the role of monokines in the generation of nonspecific suppressor T cell activity in vitro. 807 8

The pathogenesis of central nervous system disease during human immunodeficiency virus type 1 (HIV-1) infection revolves around productive viral infection of brain macrophages and microglia. Neuronal losses in the cortex and subcortical gray matter accompany macrophage infection. The question of how viral infection of brain macrophages ultimately leads to central nervous system (CNS) pathology remains unanswered. Our previous work demonstrated high-level production of tumor necrosis factor alpha, interleukin 1 beta, arachidonic acid metabolites, and platelet-activating factor (PAF) from HIV-infected monocytes and astroglia (H. E. Gendelman, P. Genis, M. Jett, and H. S. L. M. Nottet, in E. Major, ed., Technical Advances in AIDS Research in the Nervous System, in press; P. Genis, M. Jett, E. W. Bernton, H. A. Gelbard, K. Dzenko, R. Keane, L. Resnick, D. J. Volsky, L. G. Epstein, and H. E. Gendelman, J. Exp. Med. 176:1703-1718, 1992). These factors, together, were neurotoxic. The relative role(s) of each of these candidate neurotoxins in HIV-1-related CNS dysfunction was not unraveled by these initial experiments. We now report that PAF is produced during HIV-1-infected monocyte-astroglia interactions. PAF was detected at high levels in CSF of HIV-1-infected patients with immunosuppression and signs of CNS dysfunction. The biologic significance of the results for neurological disease was determined by addition of PAF to cultures of primary human fetal cortical or rat postnatal retinal ganglion neurons. Here, PAF at concentrations of > or = 300 pg/ml produced neuronal death. The N-methyl-D-aspartate receptor antagonist MK-801 or memantine partially blocked the neurotoxic effects of PAF. The identification of PAF as an HIV-1-induced neurotoxin provides new insights into how HIV-1 causes neurological impairment and how it may ultimately be ameliorated.
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PMID:Platelet-activating factor: a candidate human immunodeficiency virus type 1-induced neurotoxin. 820 37


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