Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04141 (granulocyte-macrophage colony-stimulating factor)
 6,790 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monocyte/macrophages (M/M) are an important target cell for human immunodeficiency virus (HIV) infection in the body. The study of HIV infection in these cells, however, is rather complicated because they represent a variable population, and because HIV entry and replication in M/M may be markedly influenced by a number of factors. These must be considered in therapeutic approaches to HIV infection. In the present set of experiments, we studied the interaction between certain agents which increase the infection of monocyte/macrophages (M/M) by HIV and two groups of anti-HIV agents: dideoxynucleosides and specific inhibitors of gp120-CD4 binding. We found that the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF), which markedly enhances HIV replication in M/M, does not affect the activity of recombinant soluble CD4 (sCD4) or OKT4A, two agents which block gp120-CD4 binding. However, it had varying effects on different dideoxynucleosides: GM-CSF increased the net anti-HIV activity of 3'-azido2',3'-dideoxythymidine (AZT), while at the same time it reduced the activity of 2',3'-dideoxycytidine (ddC) and 2',3'-dideoxyinosine (ddI). These effects probably represent an interplay between varying effects of GM-CSF on drug entry and phosphorylation. In additional experiments, we showed that very low concentrations of anti-HIV antibodies could enhance HIV infection of the U937 monocytoid cell line. Interestingly, while this effect has been hypothesized to occur through a CD4-independent mechanism, we found that the anti-HIV activities of both sCD4 and OKT4A were unchanged under conditions of enhancement.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Ability of anti-HIV agents to inhibit HIV replication in monocyte/macrophages or U937 monocytoid cells under conditions of enhancement by GM-CSF or anti-HIV antibody. 222 41

The ability of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and gamma interferon (IFN-gamma) to modify human immunodeficiency virus (HIV; also called HTLV-III/LAV) infection in the monocytic cell line U-937 was examined. When added to persistently infected cell cultures, GM-CSF at 30-300 units per ml produced maximal reductions in reverse transcriptase activity of 37-55% 10-14 days after its addition, whereas IFN-gamma produced reductions of 64-68% 10-17 days after addition. When used prior to acute HIV infection and maintained in the cell culture system, these cytokines reduced reverse transcriptase activity 90-100% and nearly eliminated viral antigen expression but did not prevent return of productive infection after their removal. These results indicate that, in a monocyte model of HIV infection, GM-CSF and IFN-gamma substantially restrict HIV expression and that these cytokines deserve further evaluation as therapeutic alternatives in HIV-related disorders.
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PMID:In vitro modification of human immunodeficiency virus infection by granulocyte-macrophage colony-stimulating factor and gamma interferon. 243 Feb 98

An overview of the immune system is presented, and the pathogenesis, transmission, diagnostic tests, diagnosis, immunotherapy, and vaccine development for human immunodeficiency virus (HIV) are reviewed. More than 42,000 cases of acquired immunodeficiency syndrome (AIDS) have now been reported in the United States, and an additional 250,000 cases are expected by 1991. The immunopathogenesis of HIV infection involves both cellular and humoral components of the immune system, with a characteristic depletion of helper T lymphocytes, impaired delayed hypersensitivity, and polyclonal B-cell activation. Monocytes and macrophages are also infected, and these cells provide a transport mechanism into the central nervous system. HIV is transmitted primarily by sexual, blood, and perinatal mechanisms. Enzyme-linked immunosorbent and Western blot assays are used in diagnostic tests, and diagnosis of AIDS is based on the presence of secondary infection or tumor at least moderately indicative of cellular immune deficiency in the absence of predisposing factors. Three approaches are being tested for treating HIV infection: immunomodulators, vaccines, and antiviral agents. Immunomodulators--including interferons, interleukin-2, immune reconstitution with bone-marrow transplantation and lymphocyte transfusions, transfer factor, granulocyte-macrophage colony-stimulating factor, inosine pranobex (isoprinosine), and naltrexone--are being tested with no great successes. Various approaches to vaccine development, including genetically engineered subunit proteins, synthetic peptides, and infectious recombinant viruses, are being considered. Primary immune responses do result from at least one vaccine. Future studies will evaluate combination approaches to therapy. HIV infections confront the health-care system with a serious challenge. It is too early to assess the effectiveness of the various therapeutic strategies for immune deficiencies caused by HIV.
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PMID:Current concepts in clinical therapeutics: immunologic treatment of human immunodeficiency virus infections. 244 17

Some strains of human immunodeficiency virus type 1 (HIV-1) can infect primary monocytes and monocyte-derived macrophages in vitro. In this report, the effect of cytokines on the production of one of these strains that shows a tropism for mononuclear phagocytes, designated HIV-1JR-FL, was studied. Primary peripheral blood mononuclear phagocytes infected with HIV-1JR-FL were treated with the hematopoietic factors: granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), macrophage colony-stimulating factor (M-CSF), and gamma-interferon (gamma-IFN). The M-CSF, GM-CSF, IL-3, and gamma-IFN were able to alter HIV-1 production under different conditions.
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PMID:Cytokines alter production of HIV-1 from primary mononuclear phagocytes. 304 75

Preclinical and clinical studies with an azidothymidine (AZT)/interferon-alpha (IFN-alpha) combination resulted in a marked and synergistic antiretroviral activity. The administration of the two drugs in HIV-seropositive patients affected with Kaposi's sarcoma, however, induced neutropenia, thrombocytopenia, and, in some cases, anemia. A possible means to improve the therapeutic index of AZT and/or IFN-alpha in AIDS patients could be the addition of hematopoietic growth factors. In vitro activity of cytokines on the hematotoxicity of the AZT-IFN-alpha association has not yet been studied. We have performed an in vitro study to evaluate the toxicity of AZT, IFN-alpha, or both on peripheral blood hematopoietic progenitors (CFU-GM and BFU-E) and to assess the activity of interleukin 1 (IL-1), granulocyte-macrophage colony-stimulating factor (GM-CSF), or both in modifying AZT-IFN-alpha hematotoxicity. Results indicate that AZT, IFN-alpha, and combinations of the two have a dose-dependent inhibitory effect on the in vitro growth of peripheral blood hematopoietic progenitors. Combinations of AZT and IFN-alpha inhibited CFU-GM and BFU-E proliferation in an additive manner. Neither IL-1 nor GM-CSF alone was able to induce a significant reduction of AZT-induced damage. Only the addition to the cultures of both cytokines partially curbed the antiproliferative activity of AZT at low dosages.
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PMID:Azidothymidine and interferon-alpha in vitro effects on hematopoiesis: protective in vitro activity of IL-1 and GM-CSF. 749 65

In this study, we evaluated the effect of a short-term exposure (2 hours) to two different lymphocytotropic strains of human immunodeficiency virus type 1 (HIV-1; HIVIIIB and ICR-3) on the survival of a factor-dependent CD34+ hematopoietic progenitor cell line (TF-1). At flow cytometry analysis, a significant (P < .05) increase in the frequency of apoptotic cell death was observed in HIV-1-treated TF-1 cells, supplemented with low doses of either interleukin-3 (IL-3; 0.02 to 1 ng/mL) or granulocyte-macrophage colony-stimulating factor (GM-CSF; 0.02 to 0.2 ng/mL) with respect to mock-treated cells. On the other hand, higher doses of both cytokines or combinations of suboptimal concentrations of IL-3 plus GM-CSF (eg, 0.2, plus 0.2 ng/mL) completely reversed the HIV-1-induced increase of apoptosis. Remarkably, no signs of productive or latent virus replication were ever observed in HIV-1-treated TF-1 cells up to 16 days of liquid culture. In parallel experiments, the in vitro exposure to HIVIIIB induced a significant and progressive increase of apoptotic death in purified bone marrow CD34+ cells, seeded in liquid cultures in the presence of 1 ng/mL IL-3. The HIV-1-induced apoptosis of TF-1 cells was likely triggered by the simple interaction of HIV-1 envelope glycoprotein gp120 with CD4 receptor, which was expressed at a low level on the surface of TF-1 cells. In fact, treatment of TF-1 cells with recombinant gp120 plus a polyclonal anti-gp120 antibody or with anti-CD4 monoclonal antibody plus rabbit antimouse IgG significantly increased the percentage of apoptotic death. These data suggest that HIV-1, and perhaps also free gp120 in the presence of anti-gp120 antibody; could play a direct role in the pathogenesis of peripheral blood cytopenias in acquired immunodeficiency syndrome patients by inducing apoptotic death of hematopoietic progenitor cells without the need of a direct infection.
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PMID:In vitro exposure to human immunodeficiency virus type 1 induces apoptotic cell death of the factor-dependent TF-1 hematopoietic cell line. 750 78

Combination regimens against human immunodeficiency virus type 1 (HIV-1) were studied in granulocyte-macrophage colony-stimulating factor (GM-CSF)-stimulated monocyte/macrophage cultures. Regimens included those that inhibited the same target (reverse transcriptase) or multiple targets. Treatment conditions assessed efficacy during prophylaxis and ongoing infection. Drugs included zidovudine, didanosine, nevirapine, foscarnet, pyridinone, the protease inhibitor RO31-8959 (also known as saquinavir), interferon-alpha A, the Tat inhibitor RO24-7429, and N-butyl-deoxynojirimycin. Two-, three-, and four-drug combinations were tested. Drugs were tested at individually inhibitory concentrations of IC99, IC95, IC75, and IC50. All prophylactic regimens prevented HIV-1 replication at IC99. As drug concentrations were reduced, differences among the regimens became apparent. Regimens that acted at both single and multiple targets were effective in prophylactic settings and less so in acute infection. In ongoing infections, only modest reductions in viral replication were seen, even at IC99.
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PMID:Inhibition of human immunodeficiency virus type 1 replication in cytokine-stimulated monocytes/macrophages by combination therapy. 752 25

Although human eosinophils express low concentrations of CD4, the capacity of mature, non-replicating eosinophils to be infected with human immunodeficiency virus-1 (HIV-1) has not been established. Using peripheral blood eosinophils isolated free of contaminating lymphocytes and mononuclear leukocytes, we evaluated eosinophil infection with HIV-1. Eosinophils could be infected with strains of HIV-1 as evidenced by HIV-induced cytolytic effects, progressive release of p24 antigen in cultures of infected eosinophils, recovery of HIV from infected eosinophils by co-cultivation, and detection of HIV-1 gag viral DNA from infected eosinophils by polymerase chain reaction (PCR) amplification. Greater p24 antigen release from infected eosinophils was elicited by the phorbol ester, PMA; and eosinophil killing by HIV-1 was enhanced by the cytokine GM-CSF. By light and electron microscopy, HIV-infected eosinophils demonstrated apoptosis and necrosis. Apoptotic subdiploid nuclear staining was detected by flow cytometric analyses of propidium iodide-stained nuclei from HIV-infected eosinophils, and DNA isolated from HIV-infected eosinophils showed both nucleosomal fragmentation and diffuse degradation. Thus, mature eosinophils, non-replicating terminally differentiated leukocytes, can be infected with HIV-1. HIV-1 expression in eosinophils is promoted by increased granulocyte-macrophage colony-stimulating factor (GM-CSF) and can cause eosinophils to undergo death due to apoptosis and necrosis.
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PMID:Infection, apoptosis, and killing of mature human eosinophils by human immunodeficiency virus-1. 757 98

HIV-specific cytotoxic T lymphocytes (CTLs) are an important component of the host immune response against HIV infection, and these cells release a variety of cytokines when they meet their target antigen. Since the phosphodiesterase inhibitor pentoxifylline is being used as a therapeutic agent in clinical trials of HIV infection due to its inhibitory effect on virus replication in vitro, we examined the effect of pentoxifylline on cytotoxicity and cytokine secretion by HIV-specific CD8+ CTLs. Pentoxifylline inhibited cytotoxicity of CTLs and suppressed interferon-gamma, tumor necrosis factor-alpha, and granulocyte-macrophage colony-stimulating factor release by these cells at the transcription level. Suppression of cytokine release resulted in reduced capacity of the CTLs to induce HLA class I and ICAM-1 expression and to stimulate HIV-1 replication. These results suggest that inhibition of HIV-specific CD8+ CTLs by pentoxifylline may be therapeutically relevant. Moreover, this study extends previous observations by demonstrating that, in addition to its ability to suppress cytokine production by macrophages and CD4+ T helper cells, pentoxifylline may inhibit cytotoxicity and cytokine secretion by antigen-specific CD8+ cytotoxic T lymphocytes.
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PMID:Inhibition of cytotoxicity and cytokine release of CD8+ HIV-specific cytotoxic T lymphocytes by pentoxifylline. 758 37

Since cellular activation is required for replication of human immunodeficiency virus type 1 (HIV-1), the capacity of alveolar macrophages (AM) from smokers, which are relatively activated, and nonsmokers to support the production of HIV-1JR-FL was examined. Peak HIV-1 p24 antigen level in culture supernatants of infected AM from 13 smokers was significantly higher than that of 13 nonsmokers: 31,394 +/- 8295 versus 7037 +/- 2550 pg/mL (mean +/- SE; P < .002). This difference could not be explained on the basis of viral entry, extent of reverse transcription, or release of monokines, including tumor necrosis factor-alpha, interleukin-1 beta or -6, and granulocyte-macrophage colony-stimulating factor. HIV-1 production by blood monocytes from smokers and nonsmokers infected in vitro was negligible. Thus, cigarette smoking selectively increases the susceptibility of AM to productive infection with HIV-1. This finding provides a biologic plausibility to observations that smoking may enhance the progression of AIDS.
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PMID:Enhanced production of human immunodeficiency virus type 1 by in vitro-infected alveolar macrophages from otherwise healthy cigarette smokers. 765 83


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