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)

We studied functional and immunohistochemical characteristics of cultured rat microglia. Unstimulated microglia did not proliferate. Microglia stimulated with LCM (L929 conditioned medium: colony stimulating factor-1) had proliferative activity and increased acid phosphatase activity. LPS (lipopolysaccharide) and IFN gamma (interferon-gamma) but did not affect proliferative activity. Immunohistochemically, RCA-1 lectin and GS-1 lectin, which react to beta-D-galactose and alpha-D-galactose respectively, strongly reacted to the cytoplasm and membrane of unstimulated microglia. After stimulation with LCM, microglia elongated processes and decreased response to these lectins. On the other hand, microglia stimulated with LCM showed increased reactivity to monoclonal antibody of vimentin. Microglia stimulated with LPS had round shape and had response to these lectins and vimentin. Microglia stimulated with IFN gamma had adhesive activity and weakly stained with these lectins but not with vimentin. ED-1 (monoclonal antibody of rat monocytes/macrophages) reacted to unstimulated and stimulated microglia. In flow cytometry, unstimulated microglia expressed OX-18 (MHC class I) and W3/25 (CD4) antigen. After stimulation with IFN gamma, microglia were induced to express these antigens. CD4 antigen is a marker of helper/inducer T cells and thought to be a receptor of HIV. The results that microglia had CD4 antigen which was further induced with IFN gamma are important to investigate infection of the CNS with HIV. OX-6 (Ia) antigen was induced with IFN gamma. This indicates that the microglia plays a central role in the CNS immune reaction. These characteristics of cultured rat microglia provide useful informations to investigate the pathogenesis of the CNS disorders.
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PMID:[Functional and immunohistochemical studies of cultured rat microglia]. 206 Feb 34

Twenty-one patients were prospectively randomized into a blinded double-armed crossover study comparing alpha-interferon (alpha-IFN, 10(6) IU in a 3.5% aqueous methylcellulose base) with and without 1% nonoxynol-9. Nine and twelve patients were randomized to arms with (+N) and without (-N) 1% nonoxynol-9, respectively. Patients applied the gel to affected areas every 8 hr and were evaluated biweekly. Including those crossed over, 14 patients were treated with -N. Six of fourteen (43%) achieved complete responses: biopsy proven with at least 1 year follow-up (CR). One patient achieved a partial response with at least a 50% reduction in the total surface area of all lesions present (PR). Similarly, 13 patients were treated with +N. Two patients in this group were found to have invasive cancer and one to have HIV and thus were eliminated from statistical analysis. Of the remaining 10 patients, 3 had CRs (30%), 5 had PRs (50%), and 2 failed to respond. There was no significant difference in responses between the two groups. Overall, 14 of 18 (67%) patients demonstrated some response to alpha-IFN applied topically. These data support the conclusion that alpha-IFN is an active agent in the treatment of vulvar intraepithelial neoplasia III.
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PMID:Prospective randomized trial of topical alpha-interferon (alpha-interferon gels) for the treatment of vulvar intraepithelial neoplasia III. 218 7

Neoplasms associated with acquired immunodeficiency syndrome (AIDS) present unique therapeutic challenges. High-grade systemic lymphomas, although often responsive to standard chemotherapy, will require the addition of CSFs, infection prophylaxis, and antiretroviral drugs to overcome poor marrow reserves, short response durations, and opportunistic infections. Treatment of primary central nervous system (CNS) lymphomas is complicated by their frequent occurrence as a late complication in debilitated patients. AIDS-associated Kaposi's sarcoma (KS) is a unique neoplasm whose pathogenesis is only beginning to be understood. Although responsive to standard therapy (RT, chemotherapy), considerable attention has been focused on the therapeutic potential of BRMs. Interferon alpha (IFN-alpha), which combines antiviral, antiproliferative, and immunoregulatory activities, has significant anti-KS activity, particularly in symptom-free patients with mild immunosuppression. Preliminary data links IFN-induced regression of KS to its anti-HIV activity and supports a role for endogenous IFN-alpha in the induction of refractoriness to IFN treatment. Recent data suggest synergistic anti-HIV and anti-KS activity for the combination of IFN-alpha and AZT. Additional study is needed to evaluate IFN effects on autocrine growth factors regulating the growth of KS.
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PMID:Treatment of AIDS-associated malignancy. 220 43

The effect of interferon-alpha (IFN-alpha) on virus replication in cells acutely infected with human immunodeficiency virus type 1 (HIV-1) and virus production from cells persistently infected with HIV-1 was studied. In both cell systems, significant suppression was observed. However, this suppression was not due to protein synthesis of the major viral proteins. Electron microscopy revealed the accumulation of intact virus particles on the cell surface of the cells treated with IFN-alpha. Thus, IFN-alpha might suppress the release stage of the particle from infected cells.
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PMID:Interferon-alpha treatment leads to accumulation of virus particles on the surface of cells persistently infected with the human immunodeficiency virus type 1. 221 6

A sensitive and quantitative focal immunoassay has been used to measure the effects of three different therapeutic agents on tissue culture cells infected with human immunodeficiency virus (HIV). The effects of the drugs were studied on both acutely and persistently infected CD4+ cell lines. The three agents, azidothymidine (AZT), interferon-alpha (IFN-alpha), and an anti-HIV envelope antibody coupled to ricin A chain, were tested alone and in combination. AZT was found to have its greatest effect during early stages of the infection, but also had an action on persistently infected T cell lines. The effect of AZT on persistently infected cells was seen within 24 h, increased with extended exposure to the drug, and persisted after its removal. IFN-alpha had variable effects on acutely infected cells but suppressed chronic infection. Combinations of the therapeutic agents were studied. Using a model that allowed for treatment during both acute and persistent stages of infection, the most effective combination in suppressing HIV infection was the continual use of both AZT and IFN-alpha at the highest tolerable doses. Knowledge of the efficacy of AZT on persistently infected cells will allow for the most effective design of clinical protocols.
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PMID:AZT demonstrates anti-HIV-1 activity in persistently infected cell lines: implications for combination chemotherapy and immunotherapy. 223 Feb 56

A promonocytic cell model was used to investigate cytokine gene transcription in U937 and U9-IIIB cells chronically infected with human immunodeficiency virus type 1 (HIV-1). The production of interferon (alpha-1 interferon [IFN-alpha 1], IFN-alpha 2, and IFN-beta), interleukin (interleukin 1 alpha [IL-1 alpha], IL-1 beta, and IL-6), and tumor necrosis factor alpha (TNF-alpha) mRNA was characterized by quantitative polymerase chain reaction mRNA phenotyping in U937 and U9-IIIB cells following coinfection with Sendai paramyxovirus or stimulation with lipopolysaccharide (LPS). Chronic HIV-1 infection of U9-IIIB cells resulted in a low constitutive level of transcription of TNF and IL-1 genes but not IFN genes; however, when the cells were coinfected with Sendai virus, 10- to 20-fold higher levels of IFN-beta, IL-1 beta, IL-6, and TNF-alpha mRNA were observed in U9-IIIB cells than in similarly induced U937 cells. The enhanced levels of cytokine RNA in virus-infected U9-IIIB cells were also accompanied by higher levels of IFN antiviral activity and TNF secretion than in U937 cells. Transcript levels for IFN-alpha 1 and IFN-alpha 2 were equivalently induced in virus-infected U937 and U9-IIIB cells, indicating that a generalized derepression of cytokine gene expression did not occur as a consequence of HIV-1 infection. When LPS was used as an inducer, a distinct pattern of cytokine gene expression was detected in U9-IIIB cells. TNF-alpha and IL-1 beta but not IFN-alpha or IFN-beta transcripts were induced by LPS. These results suggest that HIV-1 infection of promonocytic cells may prime or sensitize cells such that subsequent antigenic challenge leads to coordinate enhancement of cytokine gene expression.
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PMID:Coordinate enhancement of cytokine gene expression in human immunodeficiency virus type 1-infected promonocytic cells. 224 88

Interferon alpha (IFN-alpha) has been shown to be effective in treating HIV-associated KS in at least 30% of patients, and Zidovudine has proved beneficial for AIDS patients. Moreover, both drugs have demonstrated an inhibitory effect on HIV replication. Based on the above, we combined IFN-alpha and zidovudine for treatment of HIV-associated KS in order to evaluate tolerance and clinical efficacy. Twenty-one homosexual men with histologically proved HIV-associated KS were treated in an open trial with rIFN-alpha-2a 18 X 10(6) IU every second day and zidovudine 800-1200 mg/d. Treatment was discontinued within the first month in six patients: three of them developed subjective intolerance, and three others contracted severe opportunistic infections or HIV-cachexia. Fifteen evaluable patients received combination treatment over a period of 2-20 months (average 10 months). The dosage was reduced as required based on drug-induced cytotoxicity. Complete remission was observed in four patients, partial remission in three, stable disease in two, and progression in six, resulting in an overall response rate of 46%. Negative p24 expression prior to treatment was a positive predictor. Although extracutaneous involvement had a negative influence on tumor remission, even patients with a mean initial T-helper cell count below 100 mm3 responded positively. In conclusion, combination therapy of rIFN-alpha-2a with AZT may effectively control HIV-related Kaposi's sarcoma in more than 40% of patients. In contrast to monotherapy with IFN-alpha, patients with severely reduced immune systems will also benefit from combined treatment.
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PMID:Long-term combined rIFN-alpha-2a and zidovudine therapy for HIV-associated Kaposi's sarcoma: clinical consequences and side effects. 225 33

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

Human PBMC from HIV-1-infected individuals produced ex vivo in response to vesicular stomatitis virus only low amounts of IFN-alpha. This impairment was significant as early as Walter Reed (WR) stage 2; at WR stage 4-5, the production was almost zero. At WR stage 2 of infection, IFN-alpha mRNA was exclusively found in association with polyribosomes, indicating that IFN-alpha gene was transcriptionally inactive under the experimental conditions used. A similar decrease of the level of transcripts as a function of the progression of the disease was also observed for the IFN-gamma mRNA. In contrast, TNF-alpha production was strongly enhanced in PBMC from HIV-1-infected individuals after stimulation with LPS compared to the TNF-alpha production of activated PBMC from healthy donors. Almost parallel with the increase of the level of the transcript for TNF-alpha, the level of TNF-beta increases as well. Data are presented which show that the increased TNF-alpha production is due to a longer half-life of TNF-alpha transcripts in PBMC from infected individuals. These results let us suggest that the up-regulation of TNF-alpha gene expression in PBMC from HIV-infected individuals is controlled predominantly on the posttranscriptional level, whereas transcriptional events regulate the level of IFN-alpha transcripts. This assumption is supported by run-on experiments which revealed that the extent of transcription of TNF-alpha gene is almost identical in nuclei from stimulated PBMC of noninfected and HIV-infected donors, whereas the transcription of IFN-alpha gene is strongly suppressed in nuclei from HIV-infected individuals at WR stages 3 and 6.
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PMID:Differential gene expression of IFN-alpha and tumor necrosis factor-alpha in peripheral blood mononuclear cells from patients with AIDS related complex and AIDS. 229 23

Viral infection of immunocompetent cells always leads to disordered regulation of the immune system. Thus, infection by HIV1 (human immunodeficiency virus, type 1) of mononuclear phagocytes and lymphocytes is linked to the induction of the acquired immunodeficiency syndrome (AIDS). HIV1 replication in mononuclear phagocytes appears to be dependent on both the stage of maturation and on differentiation of mononuclear phagocytes. Because of the heterogeneity of the mononuclear phagocyte system, the U937 cell line provides a convenient model for studying the regulation of HIV1 replication in mononuclear phagocytes and the involvement of these cells in the immunopathogenesis of HIV1. We have shown that endogenous interferon alpha (IFN alpha) restricted viral replication in these promonocytic cells, probably by acting on proviral transcription and by interfering with transcriptional factors involved in the transactivation of the LTR (long terminal repeat) of HIV1. Indeed, addition of a monoclonal antibody to IFN alpha U937 cells cotransfected with a LTR HIV linked to the bacterial chloramphenicol acetyl transferase (CAT) gene, together with a tat expression vector, leads to an increase in CAT activity. Conversely, the addition of IFN alpha to cells cotransfected with the same vectors is followed by a decrease in CAT activity. Finally, recent experiments indicate that chronically HIV-1-infected U937 cells are more differentiated than uninfected U937 cells, suggesting that viral gene expression is able to trigger the maturation process of the promonocytic cells towards a stage where viral transcription may escape IFN alpha. These results suggest that the first replicative cycle of HIV1 in monocytes/macrophages could be a unique target for therapeutic strategies based on the use of IFN alpha.
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PMID:Regulation of HIV1 replication in promonocytic U937 cells. 234 13


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