Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0001175 (AIDS)
 120,706 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Organisms belonging to the Mycobacterium avium complex are the most common bacteria isolated from patients with AIDS. In these patients, M. avium is associated with disseminated disease, and bacteria are found within macrophages in the liver and spleen. To examine the potential of M. avium infection of a nonprofessional phagocyte, the murine fibroblast cell line (L929 cells) are infected with strain 101 (serotype 1) of M. avium. The duplication time for the intracellular bacteria was approximately 36 hr. Progressive intracellular growth ultimately resulted in the destruction of infected cells (after approximately 12 days in culture). Supernatant obtained from infected L929 cells contained interferon-beta (IFN beta) and granulocyte macrophage colony stimulating factor (GM-CSF) (50 +/- 12 ng/10(5) cells and 63 +/- 18 pg/10(5) cells, respectively, by 18 hr). IFN beta could be detected by 3 hr after infection, while GM-CSF was first detected by 6 hr. Release of IFN beta by infected L929 cells could subsequently stimulate NK cells, but not macrophages, to lyse infected L929 cells. These data using L929 cells suggest that M. avium may invade fibroblasts during the course of the infection and that fibroblast infection may trigger NK cell-mediated cytotoxicity against the infected fibroblasts.
 ...
PMID:Infection of "nonprofessional phagocytes" with Mycobacterium avium complex. 191 58

Cells of the monocyte lineage act as a major reservoir for HIV, and ways of enhancing the resistance of mononuclear phagocytes to HIV replication would be useful for delaying the onset of AIDS in infected individuals. Seif et al. (J. Virol. 65:664, 1991) have recently shown the possibility of obtaining stable antiviral expression (SAVE), directed against three nonretroviral RNA viruses, and normal cell viability in a significant percentage of murine BALB/c 3T3 cells transformed with an IFN-beta expression plasmid under the control of the 0.6-kb XhoII-NruI promoter region of the murine H-2Kb MHC gene. In the present paper, we show that it is possible to establish SAVE in human promonocytic cells. Cells of the human promonocytic U937 line were stably transfected with a human IFN-beta expression plasmid carrying the neo- and human IFN-beta-coding sequences under the control of the H-2Kb promoter fragment previously used in murine cells. After selection with G418, two transformed clones were isolated that released small amounts of human IFN-beta into the culture medium, without affecting the expression of CD4 and leucocyte function-associated Ag-1 differentiation Ag. The presence of construct-derived IFN-beta mRNA was demonstrated by polymerase chain reaction amplification of cDNA, and the level of 2-5A synthetase, one of the major IFN-induced antiviral proteins, was shown to be constitutively increased. These clones were less permissive for HIV-1 than control clones transformed with the neo gene only. The antiviral state could be modulated by anti-IFN-beta antibodies, in that the continuous presence of antibodies in the culture medium abolished the enhanced resistance to HIV-1 replication, whereas the withdrawal of the antiserum restored the antiviral state, indicating that it did indeed result from the constitutive synthesis of human IFN-beta. These results demonstrate the possibility of restricting HIV-1 replication in human promonocytic cells by establishing SAVE. Further exploration of this method as a possible approach to somatic cell gene therapy of HIV infection appears worthwhile.
 ...
PMID:Enhanced resistance to HIV-1 replication in U937 cells stably transfected with the human IFN-beta gene behind an MHC promoter fragment. 194 Mar 55

alpha-Interferon (IFN alpha) blocks replication of human immunodeficiency virus (HIV)-1 in vitro by interfering with the release of mature virions. Clinical trials have addressed the in vivo effects of IFN alpha, both alone and in combination with other agents, in a variety of patients at all stages of HIV-1 infection. Patients with late stages of HIV-1 infection (CD4 counts under 100) show few positive results following treatment with IFN alpha. Patients with earlier stages of HIV infection, however, may benefit from treatment with this agent. Several clinical trials have demonstrated the activity of interferon in the treatment of patients with acquired immunodeficiency syndrome, Kaposi's sarcoma, and CD4 counts over 200. In these trials, response rates of approximately 40% have been reported, with the probability of response directly correlated with the level of CD4 cells. These antitumor effects have been associated with declines in the circulating levels of the HIV-1 core antigen p24. alpha-Interferon activity has also been studied in patients concomitantly receiving zidovudine. In these studies, neutropenia, reversible with the concomitant administration of granulocyte macrophage colony-stimulating factor, has been the most common dose-limiting toxicity. Both the antitumor and antiviral activities of combination therapy appear to be at least as good as those observed when single agents are used. Controlled clinical trials are currently under way to evaluate the role of interferon therapy, both alone and in combination with zidovudine, in patients with early HIV infection.
 ...
PMID:The role of alpha-interferon in patients with human immunodeficiency virus infection. 194 29

Cytokines such as tumour necrosis factor (TNF) can induce HIV-1 production in T-cell tumour lines. However, it is not known if the same occurs in freshly isolated mononuclear cells, nor is it known if the virus can itself regulate cellular cytokine production. In this paper we report that HIV-1 induces peripheral blood mononuclear cells (PBMC) and CD4+ T lymphocytes to secrete TNF alpha, TNF beta and interferon-gamma (IFN gamma), three cytokines having multifunctional activities and complex physiological roles. We also show that separate addition of exogenous recombinant (r) TNF alpha or rTNF beta or rIFN gamma increases HIV-1-induced syncytium formation in both PBMC and CD4+ cells by up to 10,000-fold, with TNF alpha being most potent in this regard. Finally, we show that syncytium formation induced by diverse HIV-1 isolates and LAV-2 is inhibited without the addition of exogenous r-cytokines by the respective anti-cytokine antibodies. Our study therefore demonstrates that efficient HIV replication in primary mononuclear cells is associated with the ability of the virus to induce TNF and IFN gamma secretion.
AIDS 1990 Jan
PMID:Tumour necrosis factors (alpha, beta) induced by HIV-1 in peripheral blood mononuclear cells potentiate virus replication. 196 79

A number of immune parameters have been described as impaired in AIDS patients. The patterns of interferon-gamma (IFN-gamma) production by peripheral blood mononuclear cells (PBMC) from AIDS-related complex (ARC) and AIDS patients in response to specific and nonspecific mitogens and their relationship to proliferative responses, interaction with exogenous interleukin 2 (IL-2), and absolute CD4 cell counts were studied. The PBMC were exposed to phytohemagglutinin (PHA) or cytomegalovirus (CMV) antigen (Ag) and/or 10 units of IL-2. At selected times, culture supernatants were tested for IFN-gamma production by radioimmunoassay and at identical times proliferative responses were determined by [3H]thymidine uptake. IFN-gamma production in response to PHA or CMV Ag was inhibited significantly and appeared dependent on absolute CD4 cell counts. Proliferative responses were also similarly decreased. While IFN-gamma production to PHA was severely inhibited in PBMC only from patients with less than 100 CD4 cells/mm3, equivalent inhibition in response to CMV Ag was observed only in those with CD4 counts less than 600/mm3. IL-2 enhanced the PHA and CMV Ag-induced IFN production significantly by 2.8- and 5.3-fold respectively. Therefore, the administration of IL-2 might improve certain cell-mediated immune responses.
 ...
PMID:Patterns of interferon-gamma production by peripheral blood mononuclear cells from patients with human immunodeficiency virus infection. 197

Definition of improved therapeutic regimens of interferon-alpha (IFN-alpha) for the treatment of Kaposi's sarcoma (KS) would be useful since currently recommended doses are sometimes associated with unacceptable toxicity. IFN concentrations were measured in serum samples from men with AIDS-associated KS who were enrolled in a trial of IFN-alpha alone (16 patients) or a trial of IFN-alpha combined with zidovudine (25 patients). Analyses were done to examine the relationship between the dose of IFN-alpha, blood level of IFN, and the patient's clinical response to treatment. There was no correlation between dose of zidovudine given and response. As expected, there was a high correlation between dose of IFN-alpha and blood level in both studies (p less than 0.001). Furthermore, we found relationships between clinical response and both dose of IFN-alpha and blood level achieved. In the two studies combined, among men with greater than 200 CD4+ cells/mm3 of blood at baseline on average daily doses of greater than or equal to 10 million international units (MIU) of IFN-alpha, 13/19 (68%) responded compared to 6/17 (35%) on less than MIU (p = 0.05). Similarly, of men with IFN blood levels greater than or equal to 100 IU/mL 12/16 (75%) responded compared to 7/20 (35%) of those with blood levels less than 100 IU/mL (p = 0.02). The dose and blood levels of IFN achieved and maintained may be important factors in determining responses of KS. Additional clinical trials of IFN-alpha treatment of KS at doses about 10 MIU/day appear warranted.
 ...
PMID:Effects of interferon-alpha in patients with AIDS-associated Kaposi's sarcoma are related to blood interferon levels and dose. 210 26

Organisms belonging to the Mycobacterium avium complex (MAC) are associated with life-threatening bacteremia in patients with the acquired immunodeficiency syndrome (AIDS). As these organisms survive within macrophages, we examined the ability of recombinant human granulocyte-monocyte colony-stimulating factor (GM-CSF) to activate human monocyte-derived macrophages to inhibit the intracellular growth or kill the most mouse-virulent MAC strain in our collection that belongs to serotype 1. While unstimulated cells did not inhibit intracellular growth of MAC, macrophages activated by GM-CSF (10-10(4) U/ml) inhibited or killed up to 58 +/- 5% of the initial inoculum. This activation was dose-dependent, with maximal change occurring with a dose of 100 U/ml after 72 hr exposure. Inhibition or killing was demonstrated if GM-CSF was given both before or after establishment of infection. The combination of GM-CSF (10(2) U/ml) plus TNF (10(2) U/ml) augmented macrophage killing (range, 31 +/- 4%) compared with GM-CSF (10(2) U/ml) alone, but the combination of recombinant human interferon-gamma (IFN gamma) plus GM-CSF resulted in a significant decrease in intracellular inhibition of growth or killing (13.3 +/- 2%) compared with 57.7 +/- 5% obtained with GM-CSF alone. These results indicate that: 1) GM-CSF can activate macrophages to inhibit intracellular growth or kill MAC; 2) killing may be augmented by TNF; and 3) IFN gamma may impair GM-CSF-dependent macrophage activation.
 ...
PMID:Recombinant granulocyte-macrophage colony-stimulating factor activates human macrophages to inhibit growth or kill Mycobacterium avium complex. 211 63

Human recombinant interferon-alpha (IFN alpha) restricted viral replication in human immunodeficiency virus- (HIV) infected T cells and monocytes. With T cells, reverse transcriptase (RT) activity in culture fluids was reduced threefold from that of control infected cells by IFN treatment, but HIV p24 antigen levels were unchanged. In contrast, levels of p24 antigen and RT activity in lysates of IFN-treated infected cells were threefold greater than those of controls. These differences suggest that the mechanism for IFN-induced antiviral effects in HIV-infected T cells resides in the terminal events (assembly and release) of the virus replication cycle. Monocytes treated with IFN at the time of virus challenge showed no p24 antigen or RT activity, no HIV-specific mRNA, and no proviral DNA in cells for up to 3 weeks after infection. IFN treatment of chronically infected monocytes also decreased virus replication, as assessed by p24 antigen, mRNA and RT detection assays. However, levels of proviral DNA in the IFN-treated and control HIV-infected cells were indistinguishable. The presence of large quantities of proviral DNA in cells with little or no evidence for active transcription documents a situation approaching true microbiological latency.
AIDS Res Hum Retroviruses 1990 Aug
PMID:Restriction of HIV replication in infected T cells and monocytes by interferon-alpha. 212 Nov 92

Earlier, we reported that prophylactic treatment with human interferon gamma (rHuIFN-gamma) protected monkeys against Plasmodium cynomolgi B malaria infection. We have tested the efficacy of rHuIFN-gamma on relapsing stage of experimental P. cynomolgi B malaria infection in rhesus monkeys. No effect of rHuIFN-gamma was seen against experimental relapsing stage compared with controls; however, it appears that chloroquine (CHL) may have interfered with the antimalarial effect of IFN, since treatment with CHL inhibits the antiviral activity of mouse alpha/beta IFN and polyinosinic-polycytidylic acid (poly I:C) against Semliki forest virus (SFV) in mice. These results may have clinical implications especially with the use of IFN against virus infection, cancer and in parasitic infections in malaria endemic areas where CHL is one of the most widely used antimalarial drugs. Our result also shows that CHL treatment enhances the virus replication in mice and suggest a possible connection between AIDS and malaria infection, since the spread of AIDS has been rapid in parts of tropical Africa that have a high incidence of malaria, and chloroquine has been frequently used in the chemotherapy of malaria.
 ...
PMID:Effects of interferon in malaria infection. 212 28

Thirty seven blood samples from 21 patients with chronic brucellosis were studied for interferon response to Brucella specific antigens and to the classical IFN inducers. Whole blood technique for IFN induction and bioassay with A549 cells challenged with EMC virus for IFN detection were used. Two different antigen preparations (BRU-1 and BRU-2) used for the serologic diagnosis of brucellosis, stimulated significantly (P less than 0.001) the synthesis of IFN-alpha and IFN-gamma in the whole blood cultures from the patients with chronic brucellosis but not from the control subjects. The detoxified antigen (brucellin) was inactive as the IFN inducer. BRU-1 and BRU-2 antigens induced also low levels of IFN-alpha + IFN-gamma in the short term cultures of the separated peripheral blood leukocytes (5-10 X 10(6) cells/ml) from healthy blood donors. This resembled stimulation of the leukocytes with LPS. Brucellin was inactive in the leukocyte culture. Despite the chronic infection lasting many years the brucellosis patients had apparently intact IFN system because the response of their leukocytes to NDV, PHA + PMA or LPS was not significantly different from that of the healthy blood donors. The importance of the relative balance of the IFN system for the pathogenesis of brucellosis is suggested and contrasted with IFN disfunction in the acquired immune deficiency syndrome.
 ...
PMID:Antigen-specific and nonspecific interferon response of peripheral blood leukocytes from patients with chronic brucellosis. 212 83


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>