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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A rapid procedure for the inactivation of HIV-1-infected cells using psoralen and ultraviolet (UV) light is described. Exposure of HIV-1-infected cells to 5 micrograms/ml psoralen followed by UV irradiation (320-380 nm) for 5 minutes yields cells that are noninfectious as assessed by extended infectivity assays. The psoralen/UV inactivation procedure described is effective with cells chronically or acutely infected with HIV-1 and is unaffected by cell densities up to 12 x 10(6)/ml. At 5 micrograms/ml psoralen does little damage to cellular permeability as shown by the ability of treated cells to exclude trypan blue and propidium iodide. Psoralen/UV treatment of HIV-1-infected cells does not cause a significant decrease in the reactivity of HIV-1 core and envelope antigens or cellular antigens to monoclonal antibodies. Experiments are presented demonstrating the use of these cells for flow cytometry studies and for cell surface labeling using the lactoperoxidase 125I iodination procedure.
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PMID:Psoralen/UV inactivation of HIV-1-infected cells for use in cytologic and immunologic procedures. 234 Feb 5

Peripheral cytopenia has been reported in a number of patients with the acquired immunodeficiency syndrome (AIDS), but the mechanism of bone marrow (BM) failure is unclear. We have examined the BM morphology and cytokinetics of 16 untreated HIV-positive patients whose clinical condition ranged from asymptomatic (stage 1 WR and II CDC classifications) to overt AIDS (stage 6 WR and IV CDC classifications). BM aspirates and iliac crest threphine biopsies were obtained for myelogram and histologic examination, as well as for propidium iodide flow cytometric (FMC) DNA analysis. FCM data were compared with those from the BM of patients with solid tumors without BM involvement. Four patients had normal peripheral blood counts, 2 were anemic, 2 had granulocytopenia, 2 thrombocytopenia, 4 bicytopenia and 2 pancytopenia. BM cellularity was normal or increased, but only 2/16 patients had normal BM morphology. Ten patients had atypical lymphoid aggregates, relative plasmacytosis and eosinophilia, and 4 had typical myelodysplastic changes. There was no correlation between morphology and WR or CDC grade. The mean proliferative fraction (i.e. the percentage of cells in the S phase of the cell cycle) of the HIV-positive patients was 11% (range 5.5-18.3%). The mean value for the control patients was 15.1% (range 7.7-26.9%) (p less than 0.05). All patients had modal diploid DNA content without aneuploid clones. These data suggest that the mechanism of BM failure in HIV-positive patients lies in a reduced proliferative activity whose exact cause is still unclear.
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PMID:Bone marrow morphology and proliferative activity in acquired immunodeficiency syndrome. 250 10

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

We present the case of a 47-year-old patient who was seen for recurrent opportunistic infections. Immunophenotypic analyses disclosed severe reduction of CD4+ T cells. Repeated Elisa, Western blot and polymerase chain reaction tests for HIV were negative. The low CD4+ T lymphocyte count unaccompanied by increased CD8+ T lymphocytes and hypergammaglobulinemia, along with negativity for HIV infection, suggested the diagnosis of idiopathic CD4+ lymphocytopenia (ICL). The patient's clinical manifestations and laboratory results conformed with the case definition of ICL established in 1992 by the Centers for Disease Control of Atlanta, i.e., CD4+ T cells < 300/mm3 on two occasions and no evidence of HIV infection. In vitro analyses evidenced depressed lymphoproliferative responses to mitogens such as concanavalin A and pokeweed mitogen, while the expression of Fas antigen on peripheral lymphocytes and the percentage of apoptotic cells after propidium iodide staining were increased. Since in vitro concanavalin A stimulation inhibits T cell proliferation and induces apoptosis, these results suggest that the patient's lymphocytes are susceptible, in vivo, to an apoptotic signal.
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PMID:[Idiopathic CD4+ lymphocytopenia: a case report]. 757 16

The impact of acute malaria infection on the level of spontaneous apoptosis, i.e., the percentage of apoptotic cells detectable in lymphocytes cultured without any exogenous stimulus for 3 days in vitro, was evaluated. Quantitation of apoptosis was performed by staining of lymphocyte nuclei with propidium iodide and analysis of the fluorescence by cytometry. The mean apoptosis of 23 HIV-negative patients (15 Africans and 8 Europeans) determined during a confirmed Plasmodium falciparum attack was 27.2% (95% confidence interval (CI) = 23.5-30.7%) i.e., 2.2 times the mean level found in 49 controls (12.4%, CI = 11.1-13.6). These controls included age- and sex-matched Africans (n = 37) and Europeans (n = 12) differing only by their previous level of exposure to P. falciparum. Naive (European) as well as previously exposed (African) subjects showed dramatically elevated levels of spontaneous apoptosis during the malaria attack (mean = 22.5%, CI = 20.7-24.4 for Europeans; mean = 29.7%, CI = 24.6-34.7 for Africans). Such unusually raised levels were observed for at least 1.5 months and were probably detectable for longer periods as suggested by the fact that the mean level of spontaneous apoptosis in healthy Africans was basically higher (13.8%, CI = 12.5-15) than the one found in healthy Europeans (8.2%, CI = 6.3-10.1) (P = 0.0001). Selective immunomagnetic cell isolations carried out immediately before apoptosis quantitation showed that this process affected not only the alpha beta T cells (CD4+ T cells as well as CD8+ T cells) but also the gamma delta T cells and the B-lymphocyte subset.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Acute Plasmodium falciparum infection is associated with increased percentages of apoptotic cells. 759 Sep 29

We devised a micro-suspension-test to evaluate disinfectants against human immunodeficiency virus type-1 (HIV-1) and confirmed its reliability. Suspensions of persistently HIV-1-infected Molt-4 cells were used as targets of disinfectants and residual infectivity was measured by an infectivity assay: after cocultivation with uninfected Molt-4 cells reverse transcriptase activity (RTA) in the supernatant and giant cell formation (GCF) were monitored. Our new infectivity assay consists of a short-term assay, that is RTA and GCF monitoring on the second day of co-culture, and a long-term assay, that is RTA monitoring up to the 28th day of co-culture. The sensitivity of the short-term assay was 1 x 10(3) infected cells and that of the long-term assay 1 x 10(1) infected cells. All the chemical disinfectants examined in this study showed dose- and time-dependent inactivation of HIV-1. By 5-minute contact with ethanol, glutaraldehyde, formalin, sodium hypochlorite and povidone-iodine, HIV-1 was effectively inactivated at concentrations of 20, 0.01, 5, 0.05 and 0.1%, respectively. Since the micro-suspension-test is easy and sensitive, we recommend it as a method for evaluating disinfectants against HIV-1.
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PMID:A micro-suspension-test for evaluation of disinfectants against human immunodeficiency virus. 760 86

Jurkat cells stably expressing high levels of the HIV-1 Tat protein were generated after transfection with an Epstein-Barr virus-based episomal replicon and selection in hygromycin B. The Jurkat Tat transfectants exhibited a longer doubling time when compared to Jurkat cells or Jurkat cells transfected with the control parent plasmid. Cell cycle analysis revealed comparable durations of each phase of the cell cycle in the Tat and control transfectants. Flow cytometric analysis using Hoechst 33342 and propidium iodide staining revealed that the Tat transfectants exhibited a higher percentage of apoptotic cells when compared to the control transfectants (29.1 +/- 3.1 vs. 11.43 +/- 3.1%). Incubation of Jurkat cells with recombinant HIV-1 Tat protein resulted in induction of apoptosis. The HIV-1 Tat protein induces apoptosis in a CD4-positive T cell line. Tat-induced programmed cell death may contribute to the lymphocyte depletion seen in persons infected with HIV-1.
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PMID:HIV type 1 Tat protein induces apoptosis and death in Jurkat cells. 763 60

The neuronal loss observed in AIDS patients may be partly due to the neurotoxicity of HIV coat protein gp120, whose mechanism of action has been suggested to involve an interaction with voltage-dependent Ca2+ channels and NMDA receptors (Lipton, Trends Neurosci 15:75-79, 1992). In the present investigation we analyzed the acute neurotoxicity of gp120 on a purified neuronal population (rat cerebellar granule cell cultures) amply used for studies on glutamate toxicity. Cultures of 7-8 days were exposed for 15 min to a buffered Locke's solution containing the substances under study, washed, and cultured for another 24 hr in their original medium. The cells were stained with the nuclear dyes propidium iodide (for dead cells) and Hoechst 33258 (for total cells) and counted. Average cell death in controls was 8%. gp120 (1 pM-10 nM) caused an increase of cell death of about 80%. The effect was totally antagonized by NMDA antagonists (1 mM APV and 10 microM MK-801), by 1 microM nifedipine, and by anti-gp120 antibodies. At a concentration of 100 microM glutamate caused an average 130% increase of cell death, which was totally antagonized by APV. The effect of gp120 or glutamate did not appear to be mediated by the secretion of neurotoxins by nonneuronal cells present in a low proportion in the cultures nor to be due to the inactivation of (or competition with) neurotrophic factors present in the medium. The simultaneous administration of gp120 and glutamate (in various combinations of concentrations) had an effect that was less than additive.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Neurotoxicity of HIV coat protein gp120, NMDA receptors, and protein kinase C: a study with rat cerebellar granule cell cultures. 768 Nov 15

An AIDS patient with sporotrichosis who improved with itraconazole therapy after consecutive failure of ketoconazole, saturated solution of potassium iodide, fluconazole and amphotericin B is presented. In addition, long-term therapy with high doses of itraconazole was well tolerated and effective in avoiding relapse. Itraconazole may be suitable for use in HIV-infected patients with sporotrichosis, who probably require chronic suppressive therapy to prevent relapse of symptomatic disease.
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PMID:Efficacy of acute phase and maintenance therapy with itraconazole in an AIDS patient with sporotrichosis. 780 93

Peripheral blood mononuclear cells from HIV-infected subjects have been demonstrated by different methods to die by apoptosis after short time in culture. In the present study the percentages of apoptotic cells have been measured by propidium iodide staining and flow cytometry in PBMC from healthy controls (15) and HIV-infected subjects with asymptomatic (10) or advanced (15) disease, with or without anti-viral treatment. The percentage of apoptosis significantly correlated with clinical stage (CDCII: 15.85% +/- 9.17, CDCIV: 22.6% +/- 5.97, P < 0.001) and the CD4/CD8 CD3 cell ratio. R = -0.57, P = 0.012), while no differences were found in relation to AZT therapy. By adding IL-2 to the cultures the percentages of apoptosis of PBMC from HIV-infected patients were significantly reduced in all experiments.
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PMID:Apoptosis in HIV infection: protective role of IL-2. 786 15


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