Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the majority of adult and pediatric patients with AIDS, hematologic abnormalities including leukopenia, anemia, and thrombocytopenia are commonly observed. In addition to these findings, changes in hematopoietic progenitor cells occur, including a reduction of multipotential-forming units, granulocyte-macrophages, macrophage as well as eosinophil colony-forming units, and bone marrow erythroid burst-forming units. This study examined alterations in human fetal liver hematopoiesis in 2nd trimester abortuses from human immunodeficiency virus (HIV)-seropositive women. The differentiation and growth potential of hematopoietic cells in vitro were monitored. Upon initial isolation, some populations of liver hematopoietic cells from abortuses of HIV-seropositive women were significantly decreased when compared to age-matched samples from fetuses of normal females including the percentage of early T cells [cluster of differentiation (CD)2], B cells (CD19), and early monocytes (CD14). A decrease in multipotent progenitors (CD34), myelomonocytes (CD33), and panleukocytes (CD45) was also observed. In contrast, after 21 d in culture, cells from HIV abortuses demonstrated an increase in the percentage of CD14 cells when stimulated with erythropoietin and granulocyte-monocyte colony-stimulating factor, as well as an increase in CD45 phenotype after exposure to granulocyte-monocyte colony-stimulating factor alone. These samples showed a persistence of erythropoietic elements (transferrin and CD36 phenotype) when compared to normal controls. No significant difference in the in vitro growth of hematopoietic progenitors (bone marrow erythroid burst-forming units, granulocyte-macrophage colony-forming units, and multipotential forming units) between these samples and normal controls was found.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Alterations in human fetal hematopoiesis are associated with maternal HIV infection. 150 4

Although hypercellularity is a common bone marrow finding in patients with human immunodeficiency virus type 1 (HIV-1) infection, the effect of HIV-1 on the hematopoietic system, which has been investigated in in vitro studies, is still controversial. In this study, we have investigated the effects of HIV-1 envelope glycoprotein, gp160, on the differentiation of hematopoietic progenitor cells derived from cord blood. Culture of cord blood mononuclear cells with gp160 resulted in enhancement of the in vitro growth of myeloid hematopoietic progenitors. To investigate the mechanism of the enhancement, adherent cells, T cells, or CD34-bearing hematopoietic progenitors were isolated and cultivated with gp160 in a variety of culture conditions. We have shown that gp160 had no direct effect on highly purified hematopoietic progenitors but exerted its enhancing effect indirectly via T cells, by induction of a humoral colony-stimulating factor(s). The activity of gp160 on T cells was abrogated by preincubation of gp160 with recombinant CD4 molecule and goat anti-gp120 antibody. These data provide evidence for a novel biological activity of HIV envelope glycoprotein, that of T-cell-mediated stimulation of myelopoiesis. Binding of gp160 with the cell surface CD4 molecule appears to be necessary for secretion of the colony-stimulating factor(s).
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PMID:Effect of human immunodeficiency virus-1 envelope glycoprotein on in vitro hematopoiesis of umbilical cord blood. 152 Aug 72

Hematologic abnormalities occur in the majority of patients with acquired immunodeficiency syndrome (AIDS). Infection of the hematopoietic progenitor cells has been proposed as a potential explanation. In this study, different bone marrow cell populations, including the CD34+ hematopoietic progenitor cells, were purified by a fluorescence-activated cell sorter (FACS) and analyzed for the presence of human immunodeficiency virus-1 (HIV-1) proviral DNA using the polymerase chain reaction. A group of 14 patients with AIDS or AIDS-related complex (ARC) was studied (11 with peripheral blood cytopenias). The CD4+ helper cells in the bone marrow were found positive for HIV-1 DNA in all patients. In contrast, CD34+ progenitor cells were positive in only one patient. Two monocyte samples and two samples of CD4-/CD34- lymphocytes/blasts (mainly B and CD8 lymphocytes) were positive. Proviral DNA could not be detected in granulocytes. FACS analysis showed that the percentage of CD34+ hematopoietic progenitor cells was not altered in the bone marrow of AIDS patients in comparison with the HIV-1 seronegative controls. In contrast, the number of CD4+ lymphocytes was markedly reduced in the bone marrow of AIDS patients. These results show that the hematologic abnormalities in AIDS patients are neither explained by direct infection of the hematopoietic progenitor cells with HIV-1 nor by a depletion of progenitor cells.
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PMID:CD34+ hematopoietic progenitor cells are not a major reservoir of the human immunodeficiency virus. 169 76

To define the relationship between human immunodeficiency virus type 1 (HIV-1) infection in hematopoietic stem cells and virus production by their progeny, we performed kinetic studies infecting bone marrow (BM) stem cells and culturing them in the presence of hematopoietic growth factors. CD34-positive (CD34+), CD4-negative (CD4-) BM cells were isolated and infected in vitro with the monocytotropic HIV-1JR-FL strain or the laboratory-maintained HTLV-IIIB strain at a high multiplicity of infection. The cells were susceptible to productive infection only with HIV-1JR-FL, and virus production as measured by p24 protein release was markedly increased (more than fivefold) in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3). Macrophage CSF (M-CSF) was less stimulatory and granulocyte CSF (G-CSF) had no effect on virus production. Virus production coincided with proliferation of mononuclear phagocytes but was not related to granulocytic proliferation in G-CSF-treated BM cultures. Although peak virus production from GM-CSF-treated macrophages occurred 2 to 3 weeks after infection, peak virus production in infected stem cells was observed 5 to 6 weeks after. Enhancement in virus production had a more rapid onset when CD34+/CD4- cells were cultured in the presence of both GM-CSF and IL-3 for 7 or 14 days. Under these conditions there was a 10-fold enhancement in virus production after 7 days of preincubation and a 50-fold enhancement after 14 days. These data indicate that while the stem cell compartment may be susceptible to infection with a monocytotropic HIV-1 strain, productive and sustained infection is realized only after macrophage differentiation. The lack of effect of G-CSF on virus production is likely because of the limited effect of this hematopoietin on mononuclear phagocyte generation and function.
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PMID:Macrophage-active colony-stimulating factors enhance human immunodeficiency virus type 1 infection in bone marrow stem cells. 201 93

An important question in human immunodeficiency virus (HIV) pathogenesis is whether HIV-infected bone marrow CD34+ stem/progenitor cells serve as a significant reservoir of virus in HIV-infected individuals. Our data indicate that infection of bone marrow stem/progenitor cells with HIV occurs rarely, if ever, in vivo. In the present study, CD34+ cells were immunomagnetically purified from the bone marrow of HIV-seropositive individuals, and purified cells or colony-forming cells of the granulocyte/macrophage lineage were analyzed for HIV proviral DNA by the polymerase chain reaction. No HIV DNA was detected in colony-forming cells of the granulocyte/macrophage lineage from HIV-positive patients. Furthermore, no virus was found in CD34(+)-enriched cells from six of seven samples from asymptomatic HIV-infected individuals and four of four samples from patients with AIDS-related complex or AIDS. Thus, infected stem cells are not a major source of persistent HIV and do not account for hematopoietic suppression. These findings have positive implications for the concept of marrow reconstitution with autologous stem cells, genetically engineered for HIV resistance, following marrow-ablative antiviral therapy.
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PMID:Absent or rare human immunodeficiency virus infection of bone marrow stem/progenitor cells in vivo. 200 53

Myeloid progenitor cells were highly purified from normal human bone marrow by positive immunoselection with high-affinity monoclonal antibodies linked to magnetic beads and were successfully infected in vitro with the human immunodeficiency virus type 1 (HIV-1). From 99 to 100 percent pure bone marrow cells expressing the CD34 phenotypic marker were obtained. These cells were devoid of mature myeloid or T cell surface and intracellular markers as analyzed by immunohistochemical staining and flow cytometry. HIV-1 particles were detected by supernatant reverse transcriptase activity and transmission electron microscopy 40 to 60 days after infection. Viral particles were predominantly observed assembling and accumulating from within intracellular membranes, while phenotypically the cells were observed to have differentiated into CD4+ monocytes. These studies have important implications in understanding the pathogenesis of HIV-1 as well as the possible cause of certain of the observed hematologic abnormalities in HIV-1 infection. They also indicate that the bone marrow may serve as a potentially important reservoir of HIV-1 in the body.
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PMID:Infection and replication of HIV-1 in purified progenitor cells of normal human bone marrow. 246 Sep 22

An increasing number of diseases may be treated successfully by allogeneic bone marrow transplantation (BMT). Initially used for the treatment of immunodeficiency where a cell series or product is replaced, it has now become routine treatment for many forms of leukemia where the transplant provides the rescue after lethal marrow ablation. Recently, diseases such as thalassemia and other inherited metabolic diseases have also been treated by BMT. Formerly the problems of BMT were mainly concerned with graft versus host disease (GVHD) in HLA-matched transplants with HLA-mismatched ones not being possible as GVHD was usually fatal. Since the development of techniques for T cell removal the incidence of GVHD has greatly diminished. T cell removal has also allowed HLA haploidentical mismatched grafts to be performed successfully for immunodeficiency, but there is still a high graft rejection rate in leukemia. This also occurs to a lesser extent with HLA-matched grafts in leukemia. Furthermore, in certain forms of leukemia, particularly chronic granulocytic leukemia, the relapse rate after T cell-depleted BMT is much higher. Trials of better forms of bone marrow conditioning of the recipient are being attempted in order to prevent graft rejection and leukemia relapse. These include total lymphoid irradiation, heavier irradiation and chemotherapeutic regimens, or the use of in vivo monoclonal antibodies such as CAMPATH 1G or anti-LFA-1 (CD11a). In the future, positive selection of stem cells combined with hemopoietic growth factors may allow engraftment without graft versus host disease. This should become the method of choice for autologous transplantation for malignancy. Two monoclonal antibodies directed against the human progenitor cell antigen 1 (HPCA-1) (CD34) have been used for autologous positive stem cell selection in primates and these cells gave full hemopoietic reconstitution in the animals following lethal total body irradiation.
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PMID:Recent advances in bone marrow transplantation. 256 39

We examined 26 patients with human immunodeficiency virus-1 (HIV-1)-associated Kaposi's sarcoma (KS), and 76 HIV-1-infected (HIV-1+) people without KS or uninfected (HIV-1-) controls for the presence of circulating KS-like spindle cells. Adherent cells that had spindle morphology and several characteristics of spindle cells of KS lesions (KS cells) were identified in the peripheral blood mononuclear cell fraction only after culture in the presence of conditioned medium (CM) from activated lymphocytes. The peripheral blood-derived spindle cells (PBsc) expressed a variety of endothelial cell markers, such as Ulex europaeus I lectin, EN4, EN2/3, EN7/44, CD13, CD34, CD36, CD54, ELAM-1, and HLA-DR. However, they were negative for CD2, CD19, PaIE, and factor VIII-related antigen. The PBsc produced angiogenic factors as evidenced by the ability of CM from these cells to promote growth of normal vascular endothelial cells. In addition, subcutaneously injected PBsc stimulated angiogenesis in vivo in athymic nude mice. We determined that the number of PBsc grown from the peripheral blood of HIV-1+ patients with KS or at high risk to develop KS were increased by 78-fold (P = .0001) and 18-fold (P = .005), respectively, when compared with HIV-1- controls. The number of spindle cells cultured from the HIV-1+ patients at low risk for developing KS, eg, HIV-1+ injection drug users, showed no statistical increase when compared with HIV-1- controls. The presence of increased PBsc with characteristics of KS cells in HIV-1+ KS patients or patients at high risk for developing KS gives insights into the origin of KS cells and may explain the multifocal nature of the disease. In addition, this may be useful in predicting the risk of KS development.
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PMID:Identification and culture of Kaposi's sarcoma-like spindle cells from the peripheral blood of human immunodeficiency virus-1-infected individuals and normal controls. 863 Apr 31

It has been recently reported that murine hematopoietic stem cells and progenitors express low levels of CD4. In this study, we have investigated by phenotypic and functional analysis whether the CD4 molecule was also present on human hematopoietic progenitors. Unfractionated marrow cells or immunomagnetic bead-purified CD34+ cells were analyzed by two-color fluorescence with an anti-CD4 and an anti-CD34 monoclonal antibody (MoAb). A large fraction (25% to 50%) of the CD34+ cells was weakly stained by anti-CD4 antibodies. Moreover, in further experiments analyzing the expression of CD4 in different subpopulations of CD34+ cells, we found that CD4 was predominantly expressed in phenotypically primitive cells (CD34+ CD38-/low CD71low Thy-1high, HLA-DR+/low). However, the presence of CD4 was not restricted to these primitive CD34+ cell subsets and was also detected in a smaller fraction of more mature CD34+ cells exhibiting differentiation markers. Among those, subsets with myelo-monocytic markers (CD13, CD33, CD14, and CD11b) have a higher CD4 expression than the erythroid or megakaryocytic subsets. In vitro functional analysis of the sorted CD34+ subsets in colony assays and long-term culture-initiating cell (LTC-IC) assays confirmed that clonogenic progenitors (colony-forming unit-granulocyte-macrophage, burst-forming unit-erythroid, and colony-forming unit-megakaryocyte) and LTC-IC were present in the CD4low population. However, most clonogenic progenitors were recovered in the CD4- subset, whereas the CD4low fraction was greatly enriched in LTC-IC. In addition, CD4low LTC-IC generated larger numbers of primitive clonogenic progenitors than did CD4- LTC-IC. These observations suggest that, in the progenitor compartment, the CD4 molecule is predominantly expressed on very early cells. The CD4 molecule present on CD34+ cells appeared identical to the T-cell molecule because it was recognized by three MoAbs recognizing different epitopes of the molecule. Furthermore, this CD4 molecule is also functional because the CD34+ CD4low cells are able to bind the human immunodeficiency virus (HIV) gp120. This observation might be relevant to the understanding of the mechanisms of HIV-induced cytopenias.
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PMID:Expression of CD4 by human hematopoietic progenitors. 754 75

Uni- or multi-lineage suppression of hematopoiesis is observed in the majority of acquired immunodeficiency syndrome (AIDS) patients. The mechanism(s) underlying these abnormalities is not understood: particularly, the human immunodeficiency virus (HIV) infection of hematopoietic progenitor and stem cells (HPCs/HSCs) is highly controversial. We report that CD34+ HPCs from adult peripheral blood (PB) are in part CD4+ and susceptible to in vitro HIV infection. Primitive CD34+ HPCs were approximately 80% purified from PB. Double labeling for CD34 and CD4 membrane antigens was shown for 5% to 20% of the purified cells, thus suggesting their potential susceptibility to HIV-1 infection. The enriched HPC population, challenged with purified or unpurified HIV-1 strains, was cloned in unicellular methylcellulose culture. The single colonies generated by erythroid burst-forming units (BFU-E), granulocyte-macrophage colony-forming units (CFU-GM), and granulocyte-erythroid-macrophage-megakaryocyte colony-forming units (CFU-GEMM) were analyzed for the presence of HIV, ie, for gag DNA, tat mRNA, and p24 protein by PCR, reverse transcription PCR (RT-PCR), and enzyme-linked immunosorbent assay, respectively. In the first series of experiments incubation of HPCs with HIV-1 at multiplicities of infection (MOI) ranging from 0.01 to 10 TCID50/cell consistently yielded an 11% to 17% infection efficiency of BFU-E-generated colonies, thus indicating the sensitivity of HPCs to in vitro HIV infection. An extensive series of experiments was then performed on HPCs challenged with HIV at 0.1 MOI level. In the initial studies proviral gag sequences were detected in 9.2% of 121 analyzed CFU-GM colonies. In further experiments tat mRNA was monitored in 17% and 23% of BFU-E and CFU-GM colonies, respectively, but never in CFU-GEMM clones. Finally, 12% of CFU-GM clones and rare erythroid bursts were shown to be positive for the p24 viral protein. In control studies, purified HPCs grown in liquid suspension culture were induced to terminal unilineage erythroid, monocytic, or granulocytic differentiation: monocytes were consistently HIV-infected, whereas mature-terminal erythroblasts and granulocytes were not. Our observations indicate that a minority of primitive HPCs, but not of the multipotent type, is susceptible to in vitro HIV infection. These observations may reflect on the in vivo hematopoietic impairment in AIDS patients; more important, they provide an experimental model for studies on HIV hematopoietic infection and in vitro tests for anti-HIV HSC gene therapy.
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PMID:In vitro human immunodeficiency virus-1 infection of purified hematopoietic progenitors in single-cell culture. 753 32


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