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 early phases of human immunodeficiency virus (HIV) disease a T-cell alveolitis sustained by cytotoxic T lymphocytes (CTL) with anti-HIV activity occurs in the lung. With the progression of HIV disease, pulmonary CTL become infected and their cytotoxic activity declines. To investigate the potential causes leading to this phenomenon, we evaluated T cells obtained from the bronchoalveolar lavage (BAL) of 18 HIV-infected patients with T-cell alveolitis. BAL T cells were CD45R0+/CD8+ defined as Tc1 cells because they expressed cytoplasmic interferon gamma (IFN-gamma) and were CXCR3+/IL-12Rbeta2+. Furthermore, they bore the interleukin (IL)- 15 receptor, Fas antigen, and tumor necrosis factor receptor (TNFR) type II. When cultured for 24 h highly purified BAL T cells showed an excessive spontaneous apoptosis; after activation with anti-CD3 or ionomycin, the proportion of T cells undergoing cell death increased. Interestingly, we found a direct relationship between the predisposition to undergo spontaneous apoptosis and the levels of Fas expression by BAL T cells. Alveolar macrophages (AMs) expressed high levels of IL-15 which paralleled the intensity of T-cell infiltration in most patients. The predisposition of CD8 T cells to undergo cell death was downregulated by the incubation with IL-15; the protective effect of the cytokine was dose-dependent. Nonetheless, AMs also expressed proapoptotic molecules, including membrane TNF-alpha (mTNF-alpha). Based on these observations it may be suggested that an excessive, spontaneous, and activation-induced apoptosis of pulmonary lymphocytes may be observed in HIV lung and that AMs are major regulators of T-cell homeostasis.
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PMID:Antiapoptotic effects of IL-15 on pulmonary Tc1 cells of patients with human immunodeficiency virus infection. 1117 27

Infection of macaques with pathogenic isolates of simian immunodeficiency virus (SIV) represents a useful model of HIV infection that offers the unique opportunity to investigate the very early modifications that affect CD8(+) T-lymphocyte subsets and related cytokines during lentiviral infection. Herein, three cynomolgus macaques were inoculated intravenously with a pathogenic isolate of SIVmac 251. In fresh isolated mononuclear cells from blood, lymph node and bronchoalveolar lavage, we analyzed changes in the phenotype of CD8(+) T cells and we used reverse transcription-PCR to monitor the expression of IL-7, IL-15 and IL-16 mRNA. We demonstrated that an expansion of CD8(+)CD28(-) T cells occurs from the third week of infection on in the peripheral blood and in the lung, whereas CD8(+)CD28(+) T cells expand in the lymph nodes. Concomitantly, we evidenced mRNA modulations in IL-16, IL-15 and IL-7 expression in the three compartments studied. The containment of systemic viral replication was associated with an overexpression of IL-16 mRNA in the lung and in the peripheral blood. Given the immunomodulatory properties of IL-15 and IL-7 and the potential antiviral ability of IL-16, these perturbations could have important implications in early viral dissemination and HIV immunopathogenesis.
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PMID:Longitudinal analysis of CD8(+) T-cell phenotype and IL-7, IL-15 and IL-16 mRNA expression in different tissues during primary simian immunodeficiency virus infection. 1135 12

The reduced incidence of graft-vs.-host disease following umbilical cord blood (CB) transplantation may be related to the functional immaturity of newborn T cells expressing mainly the naive CD45RA phenotype. Expansion of CD4(+) CD45RA(+) T cells using cytokines may benefit neonates and infants with human immunodeficiency virus (HIV) infection, as a preferential decline in CD4(+) CD45RA(+) cells has been noted as HIV disease progresses. The aim of the study was to investigate the effect of interleukin (IL)-15, a novel cytokine similar to IL-2 in biological activities, on CD45RA/RO expression and apoptosis in umbilical cord blood (CB) and adult peripheral blood (APB) mononuclear cells (MNCs). Prior to culture, CB MNCs contained a greater number of CD4(+) CD45RA(+) cells and fewer CD4(+) CD45RO(+) cells than did APB MNCs. When incubated with RPMI-1640 containing 10% fetal calf serum for 7 days, the percentage of CD45RA(+) cells within CD4(+) T cells (%CD45RA(+)/CD4(+)) significantly decreased compared to that of fresh CB MNCs. IL-15 exerted a dose-dependent increase of %CD45RA(+)/CD4(+) and a corresponding decrease of %CD45RO(+)/CD4(+) in CB MNCs, an effect not observed with APB MNCs treated with IL-15. The percentages of CD45RA(+) and CD45RO(+) expression within CD8(+) cells, however, were not influenced by IL-15, in either CB or APB MNCs. A greater number of CB MNCs underwent apoptosis than did APB MNCs after 7 days of culture in RPMI-1640 containing 10% fetal calf serum. IL-15 did not inhibit apoptosis but induced proliferation comparable to that achieved in APB MNCs. The ability of IL-15 to preferentially enhance the proliferation of CD4(+) CD45RA(+) cells in CB MNCs suggests a role for immunomodulative therapy in HIV-infected newborns and infants.
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PMID:Interleukin-15 enhances CD4(+) CD45RA(+) expression on umbilical cord blood mononuclear cells. 1155 15

The effects of genetic adjuvants on humoral and cell-mediated immunity to two human immunodeficiency virus antigens, Env and Nef, have been examined in mice. Despite similar levels of gene expression and the same gene delivery vector, the immune responses to these two gene products differed following DNA immunization. Intramuscular immunization with a Nef expression vector plasmid generated a humoral response and antigen-specific gamma interferon (IFN-gamma) production but little cytotoxic-T-lymphocyte (CTL) immunity. In contrast, immunization with an Env vector stimulated CTL activity but did not induce a high-titer antibody response. The ability to modify these antigen-specific immune responses was investigated by coinjection of DNA plasmids encoding cytokine and/or hematopoietic growth factors, interleukin-2 (IL-2), IL-12, IL-15, Flt3 ligand (FL), and granulocyte-macrophage colony-stimulating factor (GM-CSF). Coadministration of these genes largely altered the immune responses quantitatively but not qualitatively. IL-12 induced the greatest increase in IFN-gamma and immunoglobulin G responses to Nef, and GM-CSF induced the strongest IFN-gamma and CTL responses to Env. A dual approach of expanding innate immunity by administering the FL gene, together with a cytokine that enhances adaptive immune responses, IL-2, IL-12, or IL-15, generated the most potent immune response at the lowest doses of Nef antigen. These findings suggest that intrinsic properties of the antigen determine the character of immune reactivity for this method of immunization and that specific combination of innate and adaptive immune cytokine genes can increase the magnitude of the response to DNA vaccines.
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PMID:Effects of antigen and genetic adjuvants on immune responses to human immunodeficiency virus DNA vaccines in mice. 1173 89

Our knowledge of NK cells and their critical role in the innate immune system has increased enormously since their discovery several decades ago. However, it is only within the last 10 years that rational cytokine therapies, such as those utilizing low doses of IL-2, have been successful in expanding NK cells in patients with cancer and/or immunodeficiency. Such experiences in vivo have highlighted the importance of basing immunotherapeutic strategies on the known cellular and molecular properties of the targeted cell population. Recent advances in our understanding of the physiologic factors and events that orchestrate NK cell ontogeny, including IL-15 and receptor tyrosine kinase ligands to c-kit and flt3, provide novel therapeutic possibilities for cytokine therapy. This review summarizes our current understanding of human NK cell ontogeny, and links this knowledge to ongoing and future clinical strategies for the endogenous expansion of NK cells in patients with cancer and/or immunodeficiency.
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PMID:Ontogeny and expansion of human natural killer cells: clinical implications. 1187 13

Human immunodeficiency virus (HIV)-1 Nef protein is an essential modulator of AIDS pathogenesis and we have previously demonstrated that rNef enters uninfected human monocytes and induces T cells bystander activation, up-regulating IL-15 production. Since dendritic cells (DCs) play a central role in HIV-1 primary infection we investigated whether rNef affects DCs phenotypic and functional maturation in order to define its role in the immunopathogenesis of AIDS. We found that rNef up-regulates the expression on immature DCs of surface molecules known to be critical for their APC function. These molecules include CD1a, HLA-DR, CD40, CD83, CXCR4, and to a lower extent CD80 and CD86. On the other hand, rNef down-regulates surface expression of HLA-ABC and mannose receptor. The functional consequence of rNef treatment of immature DCs is a decrease in their endocytic and phagocytic activities and an increase in cytokine (IL-1beta, IL-12, IL-15, TNF-alpha) and chemokine (MIP-1alpha, MIP-1beta, IL-8) production as well as in their stimulatory capacity. These results indicate that rNef induces a coordinate series of phenotypic and functional changes promoting DC differentiation and making them more competent APCs. Indeed, Nef induces CD4(+) T cell bystander activation by a novel mechanism involving DCs, thus promoting virus dissemination.
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PMID:HIV-1 Nef induces dendritic cell differentiation: a possible mechanism of uninfected CD4(+) T cell activation. 1196 93

My work on basic and clinical immunology has focused on the regulation of the human immune response and how its dysregulation can lead to immunodeficiency, autoimmune, and malignant disorders. The early focus in our laboratory was on pathogenic mechanisms underlying hypogammaglobulinemia. Our demonstration of active suppression by human suppressor T cells changed thinking about the pathogenesis of certain immunodeficiency disorders. Recently we have focused on the cytokines interleukin-2 (IL-2) and IL-15, which have competitive functions in adaptive immune responses. IL-2 is necessary to destroy self-reactive lymphocytes and thus favors peripheral tolerance to self-antigens, whereas IL-15 favors the persistence of lymphocytes involved in the memory and effector responses to invading pathogens but risks the development of inflammatory autoimmune diseases. Our murine anti-Tac monoclonal antibody exploits these differences, as does a humanized form (daclizumab) now approved for the prevention of renal allograft rejection. New forms of therapy directed at IL-2 and IL-15 receptors may be effective against certain neoplastic diseases and autoimmune disorders and in the prevention of allograft rejection.
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PMID:The meandering 45-year odyssey of a clinical immunologist. 1235 37

We have investigated the capacity of two human immunodeficiency virus type 1-derived lentivectors, differing in the presence of a 118-bp pol fragment containing the cPPT/CTS element, to transduce human normal primary cells of different hematopoietic lineages. Infection of resting monocytes with a high multiplicity of infection (MOI > 10) revealed that the lentivirus carrying the pol fragment (cPPT) is effective, transducing 75% of cells compared with 36% for the no-cPPT vector. Even at low MOIs (< or =1) the cPPT vector still shows a better transduction efficiency than the no-cPPT vector. Moreover, transduction does not require dendritic cell differentiation. In contrast, infection of nonactivated T lymphocytes showed that both vectors, tested at high MOIs, can transduce a small, although measurable, percentage of cells (up to 10%), which may correspond to G(1a) "activated" cells as detected by simultaneous staining of DNA and RNA, in our cultures in the presence of medium alone. Furthermore, we show that the sole addition of interleukin 2 or interleukin 15 represents a full proliferative signal under our conditions and permits high transduction efficiency (up to 30% with the cPPT vector and 15% with the no-cPPT vector). Still higher transduction of T lymphocytes can be achieved after stimulation with phytohemagglutinin and interleukin 2 (up to 78% with the cPPT vector vs. 42% with the no-cPPT vector). Finally, both viruses do not transduce either resting or proliferating tonsillar B lymphocytes.
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PMID:A human immunodeficiency virus type 1 pol gene-derived sequence (cPPT/CTS) increases the efficiency of transduction of human nondividing monocytes and T lymphocytes by lentiviral vectors. 1239 13

LP-BM5 murine leukemia virus (MuLV) infection causes murine acquired immunodeficiency syndrome (MAIDS), a disease characterized by varied functional abnormalities of immunocompetent cells. We found that MAIDS progression was severely retarded in IL-15 transgenic (Tg) mice constructed with cDNA encoding secretable IL-15 under the control of an MHC class I promoter. Several immune defects, including impaired natural killer activity, depressed IFN-gamma production by T cells stimulated with anti-T cell receptor cross-linking, and increased susceptibility to Mycobacterium bovis infection, were prevented in IL-15 Tg mice inoculated with LP-BM5 MuLV. Cytotoxic T lymphocyte response to a highly antigenic 10-mer peptide encoded by LP-BM5-defective virus gag p12 gene was detected in the spleen and peritoneal exudate cells from IL-15 Tg mice infected with LP-BM5 MuLV. Intramuscular injection of cDNA encoding secretable IL-15 also prevented the development of MAIDS. These results indicate that IL-15 prevents the progression of MAIDS and may provide insight into an immunotherapeutic approach using the IL-15 gene for controlling retrovirus-induced immunodeficiency.
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PMID:Overexpression of interleukin-15 prevents the development of murine retrovirus-induced acquired immunodeficiency syndrome. 1240 18

We investigated the effects of human immunodeficiency type-1 virus (HIV-1) matrix protein p17 on freshly isolated and purified human natural killer (NK) cells. HIV-1 p17 increased the cytokines interleukin (IL) 2, IL-12 and IL-15, and induced natural killer cell proliferation, but not cytotoxicity. This effect was specific because it was abrogated by anti-p17 monoclonal antibody. Moreover, HIV-1 p17 enhanced the cytokine-induced production of tumour necrosis factor (TNF)-alpha and interferon (IFN)-gamma by NK cells. IL-4 downregulated IFN-gamma and TNF-alpha secretion in IL-2- and IL-15-treated NK cells. HIV-1 p17 restored the ability of NK cells to produce both cytokines when added to the cultures simultaneously with IL-4. The property of p17 to increase the production of TNF-alpha and IFN-gamma might be a mechanism used by HIV-1 to modulate the immune system to support its replication and spreading.
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PMID:HIV-1 matrix protein p17 enhances the proliferative activity of natural killer cells and increases their ability to secrete proinflammatory cytokines. 1254 96


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