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Biomedical subjects

J E Groopman

Publications and source records attributed to J E Groopman.

At least 91 records · Page 5Linked to original sources
PubMed1990

Lack of evidence for infection of or effect on growth of hematopoietic progenitor cells after in vivo or in vitro exposure to human immunodeficiency virus.

The pathogenesis of the hematologic abnormalities commonly observed in patients with acquired immunodeficiency syndrome (AIDS) is incompletely understood. We report here that in vitro growth of myeloid (CFU-GM) and erythroid (BFU-E) progenitor cells from six patients with AIDS was not significantly different from that of normal human immunodeficiency virus (HIV) seronegative donors: 25.3 +/- 5 CFU-GM per 5 x 10(4) low density marrow cells and 33.5 +/- 5 BFU-E were observed in AIDS patients versus 32.7 +/- 5 CFU-GM and 42.1 +/- 5 BFU-E in controls. Furthermore, no HIV-DNA in individual colonies (CFU-GM and BFU-E) could be detected using the polymerase chain reaction (PCR) technique, although HIV-1 DNA was detected in peripheral blood mononuclear cells from the same patients. Similarly, normal bone marrow cells exposed in vitro to different isolates of HIV or recombinant purified HIV-1 envelope glycoprotein (gp) 120 did not exhibit any difference in growth of CFU-GM or BFU-E as compared with mock exposed bone marrow cells. HIV-1 DNA could not be detected by the PCR technique in individual colonies derived from HIV exposed marrow. This study suggests that committed myeloid and erythroid progenitors from AIDS patients are responsive to hematopoietic growth factors in vitro and do not appear to contain HIV-1 DNA. Also, HIV or its envelope gp did not alter the growth of hematopoietic progenitor cells in vitro. No evidence of HIV infection of progenitor cells could be demonstrated. Impaired hematopoiesis in patients with AIDS may not be related to direct effects of HIV on committed progenitor cells.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Human immunodeficiency virus infection of human bone marrow stromal fibroblasts.

The human immunodeficiency virus (HIV) preferentially infects CD4 positive T cells and monocytes. Other human cell types have been reported to be infectable with HIV, including cells of mesenchymal origin. In this report, we show that both primary human bone marrow stromal fibroblasts and an immortalized human stromal fibroblast line are susceptible to HIV infection. These cells are capable of passing HIV to cells of lymphoid or myeloid lineage, and may thereby act as a reservoir of virus. This in vitro system may be a useful model for assessing the pathophysiology of hematopoietic dysfunction in AIDS patients.

Actins↗
PubMed1990

Recombinant human erythropoietin for patients with AIDS treated with zidovudine.

Bone marrow suppression and anemia are frequent side effects of treatment of the acquired immunodeficiency syndrome (AIDS) with zidovudine (formerly azidothymidine [AZT]). We conducted a randomized, double-blind, placebo-controlled clinical trial of recombinant human erythropoietin (100 U per kilogram of body weight thrice weekly by intravenous bolus) in 63 patients with AIDS treated with zidovudine (29 in the erythropoietin group and 34 in the placebo group). Reductions in the number of units of red cells transfused and the number of patients given transfusions per month became apparent in the second and third months of the trial. The reductions were observed in patients with endogenous erythropoietin levels less than or equal to 500 IU per liter at base line, but not in patients whose levels were greater than 500 IU per liter at the beginning of the study. Although the hematocrit and hemoglobin level were not used as the primary criteria of efficacy because the patients received transfusions when their physicians decided that they needed them, a significantly higher rate of increase in the hematocrit was observed in the patients treated with recombinant human erythropoietin whose levels of endogenous erythropoietin were less than or equal to 500 IU per liter (0.00353 points per week) than in the patients given placebo (0.00116 points per week). This effect was not seen in patients with higher levels of endogenous erythropoietin. Serious side effects did not occur more often in the group treated with erythropoietin than in the placebo group. We conclude that recombinant human erythropoietin may be useful in patients with AIDS treated with zidovudine, although the indicators for its use remain to be clarified.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Biological properties of a CD4 immunoadhesin.

Molecular fusions of CD4, the receptor for human immunodeficiency virus (HIV), with immunoglobulin (termed CD4 immunoadhesins) possess both the gp120-binding and HIV-blocking properties of recombinant soluble CD4, and certain properties of IgG, notably long plasma half-life and Fc receptor binding. Here we show that a CD4 immunoadhesin can mediate antibody-dependent cell-mediated cytotoxicity (ADCC) towards HIV-infected cells, although, unlike natural anti-gp120 antibodies, it does not allow ADCC towards uninfected CD4-expressing cells that have bound soluble gp120 to the CD4 on their surface. In addition, CD4 immunoadhesin, like natural IgG molecules, is efficiently transferred across the placenta of a primate. These observations have implications for the therapeutic application of CD4 immunoadhesins, particularly in the area of perinatal transmission of HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1990

The safety and pharmacokinetics of recombinant soluble CD4 (rCD4) in subjects with the acquired immunodeficiency syndrome (AIDS) and AIDS-related complex. A phase 1 study.

STUDY OBJECTIVE: To evaluate the safety and pharmacokinetics of recombinant, soluble human CD4 (rCD4) in subjects with the acquired immunodeficiency syndrome (AIDS) and AIDS-related complex. The protein rCD4 binds to envelope protein, gp120, of the human immunodeficiency virus (HIV) and blocks HIV infection of CD4 lymphocytes in vitro. DESIGN: Phase 1 trial with dose escalation. SETTING: Two university-affiliated hospital clinics. SUBJECTS: Of 42 subjects enrolled, 29 had AIDS and 13 had AIDS-related complex. INTERVENTIONS: The rCD4 was administered by rapid intravenous infusion on day 1, followed by a 3-day washout, then once a day for 10 days, followed by a 7-day washout, and then three times a week for 8 weeks. Doses of 1, 10, 30, 100, and 300 micrograms/kg body weight per day of rCD4 were administered intravenously to 6 subjects at each dose level. Twelve additional patients received 300 micrograms/kg.d of rCD4: 6 by intramuscular and 6 by subcutaneous injection. All subjects were monitored for toxicity. Immunologic and virologic variables were also monitored. MEASUREMENTS AND MAIN RESULTS: Administration of rCD4 was not associated with important toxicity as determined by clinical monitoring or by serum chemistry, hematologic, or immunologic variables. No subjects required dose reduction or discontinuation of therapy due to rCD4-related toxicity. No consistent or sustained changes in CD4 lymphocyte populations or HIV antigen levels were observed. The volume of distribution of rCD4 was small, and clearance remained constant over the dose range studied. The bioavailability of intramuscular injection and subcutaneous injection was 51% and 45%, respectively. CONCLUSIONS: At the dose levels used in this study, rCD4 appears safe and well tolerated. Serum concentrations of rCD4 were achieved that were comparable to concentrations shown to have antiviral activity in vitro. Further studies are indicated to determine whether rCD4 or related molecules will be useful in treating HIV infection.

AIDS-Related Complex↗
PubMed1990

Inhibition of serum-enhanced HIV-1 infection of U937 monocytoid cells by recombinant soluble CD4 and anti-CD4 monoclonal antibody.

Mononuclear phagocytes can be infected with the human immunodeficiency virus type 1 (HIV-1). Although these cells express CD4 antigen, which is the recognized cellular receptor for HIV, additional cell surface proteins such as the Fc receptor, might serve as receptors for infection. In order to study this possibility we used the U937 monocytic cell line as a target for HIV infection. Flow cytometry of U937 showed that 97% of cells expressed CD4, 33% expressed the high affinity 72 kD Fc receptor (FcRI), and 74% expressed the low-affinity 40 kD Fc receptor (FcRII). Virus neutralization tests were performed by preincubating heat-inactivated human anti-HIV sera with HIV-1, IIIB strain, and then challenging U937. After 13 days in culture, productive HIV-1 infection was monitored by reverse transcriptase activity. High concentrations of certain sera (10(-1)-10(-3) dilutions) neutralized HIV-1, but at subneutralizing concentrations (10(-4)-10(-6) dilutions), five of these sera enhanced viral infection approximately two- to threefold. This enhancement of HIV-1 infection was totally blocked by 1 microgram/ml recombinant soluble CD4 (rCD4) or by 0.5 microgram/ml anti-CD4 Leu3a monoclonal antibody. These results suggest that serum enhancement of HIV-1 infection, thought to be due to binding to the monocyte Fc receptor, requires HIV-1 binding to CD4, since rCD4 or Leu3a blocked this phenomenon.

AIDS-Related Complex↗
PubMed1990

Production of cytokines by peripheral blood monocytes/macrophages infected with human immunodeficiency virus type 1 (HIV-1).

The study of monocyte/macrophage functions after human immunodeficiency virus type 1 (HIV-1) infection may help in understanding the pathogenesis of AIDS. The production of four cytokines, tumor necrosis factor alpha (TNF alpha), interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), and granulocyte-macrophage colony-stimulating factor (GM-CSF), by peripheral blood monocytes/macrophages was evaluated after in vitro infection with HIV-1. HIV-1 infection of these monocytes/macrophages did not result in release of any of these cytokines. Similarly, treatment of uninfected cells with purified recombinant HIV-1 envelope protein did not result in cytokine production. After stimulation with endotoxin or endotoxin plus interferon-gamma, HIV-1-infected monocytes/macrophages produced amounts of TNF alpha, IL-6, GM-CSF, and IL-1 beta comparable to that of uninfected cells. HIV-1 infection does not appear to induce or alter cytokine production by mononuclear phagocytes, which retain the capacity to produce these cytokines after endotoxin stimulation.

Biological Factors↗
PubMed1990

CD4 immunoadhesin, but not recombinant soluble CD4, blocks syncytium formation by human immunodeficiency virus type 2-infected lymphoid cells.

Recombinant soluble CD4 (rCD4) has been shown to be an effective inhibitor of human immunodeficiency virus type 1 (HIV-1) and HIV-2 infection of lymphoid cells in vitro. In this report, we characterized the effects of rCD4, the V1V2 fragment of CD4, and the immunoadhesin CD4-immunoglobulin G on syncytium formation between lymphoid cells infected by HIV-1 or HIV-2 and uninfected cells. All three molecules blocked HIV-1-mediated syncytium formation, but only CD4-immunoglobulin G blocked HIV-2-mediated syncytium formation. rCD4 and the V1V2 fragment of CD4 enhanced HIV-2-mediated syncytium formation. These results suggest that the process of cell fusion is significantly different between HIV-1- and HIV-2-infected cells.

CD4 Antigens↗
PubMed1990

Human immunodeficiency virus does not induce interleukin-1, interleukin-6, or tumor necrosis factor in mononuclear cells.

The production of interleukin-1 beta (IL-1 beta), IL-6, and tumor necrosis factor alpha (TNF-alpha) by fresh peripheral blood mononuclear cells was evaluated after exposure to human immunodeficiency virus (HIV) or purified recombinant HIV-1 envelope glycoprotein (rgp120). To exclude the role of contaminating endotoxin in this study, all media were subjected to ultrafiltration and reagents contained less than 25 pg of endotoxin per ml by Limulus assay. Under endotoxin-free conditions, no increases in IL-1 beta, IL-6, or TNF-alpha mRNA or protein were detectable in cell cultures exposed to HIV-1, HIV-2, or rgp120 (0.1 to 10 micrograms/ml), as compared with cytokine levels in mock-exposed cultures. However, concentrations of endotoxin (lipopolysaccharide) as low as 0.5 ng/ml induced significant production of mRNA and protein for these three cytokines. Preincubation of mononuclear cells with "shake" HIV-1 preparations and also mock-infected shake preparations prior to lipopolysaccharide stimulation resulted in a two- to threefold increase in IL-1 beta and TNF-alpha production. This priming effect was not observed with rgp120 (0.1 to 10 micrograms/ml) or standard HIV-1 or mock-infected supernatants, suggesting the presence of biologically active material independent of virus in the shake preparations. Our studies indicate that, in the absence of endotoxin, HIV-1, HIV-2, and HIV gp120 do not induce production of IL-1 beta, IL-6, or TNF-alpha by peripheral blood mononuclear cells.

Cells, Cultured↗
PubMed1990

Infection of nonlymphoid cells by human immunodeficiency virus type 1 or type 2.

Human epithelial cells (L132) derived from embryonic lung and human lung fibroblasts (MRC5) were infected by human immunodeficiency virus type 1 (HIV-1) or type 2 (HIV-2). Surface CD4 protein was detected on these cells, and recombinant soluble CD4 (sCD4) blocked infection, indicating that HIV infection was mediated by the cell surface CD4 protein. In contrast, infection of human primary chondrocyte cells (C23), synovial cells (HSA), and foreskin fibroblasts (F13) was apparently independent of cell CD4-mediated mechanisms. Surface CD4 protein could not be detected on these cells, and sCD4 did not block the infection. F13 cells could be infected only by HIV-2, not by HIV-1, under our experimental conditions. In cells of mesenchymal orgin, viral production could be detected only after cocultivation with the human T-lymphoid H9 cells but not by conventional viral assays, including reverse transcriptase and p24 antigen assays in cell culture supernatant and immunofluorescence of host cells. Our DNA transfection studies indicated that this lack of detectable viral production was not due to the inefficient use of the HIV long terminal repeat or the Tat protein in these cells. These mesenchymal and epithelial cells were susceptible to HIV infection but differed in mechanism of virus entry compared with hematopoietic cells such as T lymphocytes. These observations may provide insights into clinical syndromes such as lung dysfunction in HIV-infected newborns and connective tissue disorders in HIV-infected adults.

Antigens, CD↗
PubMed1990

Retroviral infection and haemopoiesis.

Human retroviruses have been recognized for the last decade as pathogens for malignant or immunodeficient disease states. The human immunodeficiency virus (HIV) is the causal agent for the acquired immune deficiency syndrome (AIDS). Impaired haemopoiesis is common after HIV infection. The pathophysiology of this is not yet fully understood, but may involve direct retroviral infection of progenitors and/or elaboration of suppressor substances by accessory cells in the bone marrow microenvironment. Haemopoietic growth factors have been particularly useful in reconstituting myelopoiesis and erythropoiesis in HIV-infected patients with impaired bone marrow function.

Hematopoiesis↗
PubMed1990

Granulocyte-macrophage colony-stimulating factor in human immunodeficiency virus disease.

Factors contributing to the development of cytopenias in patients with advanced human immunodeficiency virus (HIV) disease include primary HIV-related suppression of blood cell production, opportunistic infections and neoplasms that directly involve the marrow cavity, and the toxicity of antiviral, antiinfective, and antineoplastic therapy. Indeed, bone marrow toxicity is often the complication limiting delivery of effective therapy in such patients. Recombinant granulocyte-macrophage colony-stimulating factor (GM-CSF) has been shown to increase the leukocyte count in this patient population. Although there is concern that GM-CSF administration may increase HIV replication in myeloid cells, this effect has not been observed in clinical studies. In addition, the most appropriate use of hematopoietic growth factors would be in combination with effective antiretroviral agents, such as zidovudine. A pharmacologic basis for such combination is provided by the finding that inhibition of HIV by zidovudine may be augmented by GM-CSF. It recently has been shown that patients with severe leukopenia and intolerance to zidovudine can have reconstitution of effective myelopoiesis with low doses of subcutaneously self-administered GM-CSF and become hematologically tolerant of zidovudine 1,200 mg/d. The major adverse effects of this combination regimen were constitutional symptoms and thrombocytopenia. Further investigation of GM-CSF and other hematopoietic growth factors in this patient population is warranted.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Status of colony-stimulating factors in cancer and AIDS.

The major hematopoietic growth factors have been produced through recombinant DNA technology and have entered initial clinical trials; results of these trials will be reviewed here. Granulocyte colony-stimulating factor (G-CSF) has been tested in patients with bladder cancer and small-cell carcinoma of the lung. In these studies, G-CSF ameliorated the leukopenia associated with combination chemotherapy, reduced the incidence of mucositis in the bladder cancer patients, and nearly eliminated the occurrence of serious infections in the lung cancer patients. Trials involving another factor, granulocyte macrophage colony-stimulating factor (GM-CSF), have resulted in a marked increase in white blood cell (WBC) counts in patients with myelodysplastic syndromes, and has accelerated the appearance of leukocytes and platelets after autologous bone marrow transplants. GM-CSF can also increase the WBC counts in acquired immunodeficiency syndrome patients treated with zidovudine. Both G-CSF and GM-CSF may produce multilineage effects in certain clinical settings and dose ranges. Finally, interleukin-1 (IL-1) and IL-3, which commit very early stem cells to a myeloid pathway, may be used in combination with G-CSF or GM-CSF to produce a synergistic response to various clinical situations.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Hematopoietic growth factors. Biology and clinical applications.

The hematopoietic growth factors are potent regulators of blood-cell proliferation and development. The first phase of clinical trials suggests that they may augment hematopoiesis in a number of different conditions of primary and secondary bone marrow dysfunction. Future clinical use is likely to include combinations of these growth factors, in order to stimulate early marrow progenitors and obtain multilineage effects. An improved understanding of the biologic and clinical effects of hematopoietic growth factors promises future clinical applications for conditions of impaired function and reduced numbers of blood cells.

Colony-Stimulating Factors↗
PubMed1989

Prolonged zidovudine therapy in patients with AIDS and advanced AIDS-related complex. AZT Collaborative Working Group.

We examined the long-term safety and efficacy of zidovudine therapy in 229 subjects with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex who previously participated in a placebo-controlled study of zidovudine. One hundred two placebo recipients (delayed treatment group) and 127 zidovudine recipients (original treatment group) were followed up while receiving zidovudine therapy for a mean of 21 months. Survival rates for the original treatment group were 84.5% and 57.6% at 12 and 21 months, respectively; for the delayed treatment group, 78.8% and 64.6% at 12 and 21 months, respectively, and 78.8% and 47.5% at 12 and 21 months, respectively, for 77 subjects with AIDS and 93.0% and 71.8%, respectively, for 50 subjects with AIDS-related complex in the original treatment group. Adverse reactions decreased over time and newly observed toxic reactions were unusual. The clinical course of these subjects suggests continued survival benefits with long-term zidovudine therapy.

AIDS-Related Complex↗