Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A multiple immunodeficiency, involving antibody- and cell-mediated responses in 10 Chinese Shar-Pei (CSP) dogs is described. Abnormal levels of serum IgM and IgA in most cases, and IgG in fewer cases characterized the immunoglobulin deficiencies. Decreased in vitro proliferative responses of pokeweed mitogen (PWM)-stimulated peripheral blood mononuclear cells (PBMC) were found in nine cases. Clinical presentation involved several organ systems and was associated with recurrent infections and malignancy. Sera from affected dogs suppressed PWM-stimulated cell proliferation of affected and normal dogs, but not cultures stimulated with PWM followed by recombinant IL-2 (rIL-2). In vitro supplementation of PBMC cultures with immunomodulatory guanosine analogs (GA) resulted in increased de novo IgG and/or interleukin-6 (IL-6) synthesis. Cells from five immunodeficient dogs showed in vitro evidence of GA- or rIL-2-dependent enhanced immunological responses. Since rIL-2-mediated activation of the IL-2 receptor and GA-mediated immunomodulation are reported to act through protein kinase C (PKC)-independent pathways, it is concluded that the IL-2 receptor is functional in these dogs and that cell activation through alternative pathways may restore immune responses in affected CSP dogs.
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PMID:A primary immunodeficiency syndrome in Shar-Pei dogs. 785 14

We recently reported clonal human immunodeficiency virus (HIV involvement in four acquired immune deficiency syndrome (AIDS)-associated non-B-cell lymphoproliferations. In three of these cases HIV expression was localized to tumor-associated macrophages. Because one of the cases had a major component involved in angioproliferation, we speculated that some form of Kaposi's sarcoma (KS), which also has a major component of angioproliferation, might be involved clonally with HIV. The current study is an evaluation of four cases of KS and control tissues taken from four patients who died with complications of HIV disease. With use of the inverse polymerase chain reaction technique to identify clonal forms of HIV, a clonal form of HIV was found in one of four KS cases. The HIV-positive tumor was an early KS lesion of the bowel, and uninvolved bowel from the same patient showed no clonal HIV. Immunohistochemical analysis demonstrated the presence of prominent HIV-expressing macrophages that also coexpressed high levels of HIV tat, basic fibroblast growth factor, and interleukin-6. These data provide evidence for a pathogenic process termed "sequential neoplasia," wherein a clonal macrophage provides a growth factor milieu stimulating the proliferation of a responder cell population that ultimately becomes autonomous. In the current case, the macrophages expressing HIV were located adjacent to the KS tumor tissue and were found to be producing known KS growth factors. The absence of finding clonal HIV in three more advanced KS lesions suggests that the clonal macrophage may be required only for early pathogenesis and that sequential neoplastic changes occurring in the endothelial cells gave rise to autonomous KS.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Identification of a clonal form of HIV in early Kaposi's sarcoma: evidence for a novel model of oncogenesis, "sequential neoplasia". 788 3

Human cytomegalovirus (HCMV) and human immunodeficiency virus type 1 (HIV-1) may interact in the pathogenesis of AIDS. The placental syncytiotrophoblast layer serves as the first line of defense of the fetus against viruses. We analyzed the patterns of replication of HIV-1 and HCMV in singly an dually infected human term syncytiotrophoblast cells cultured in vitro. Syncytiotrophoblast cells exhibited restricted permissiveness for HIV-1, while HCMV replication was restricted at the level of immediate-early and early gene products in the singly infected cells. We found that the syncytiotrophoblasts as an overlapping cell population could be coinfected with HIV-1 and HCMV. HIV-1 replication was markedly upregulated by previous or simultaneous infection of the cells with HCMV, whereas prior HIV-1 infection of the cells converted HCMV infection from a nonpermissive to a permissive one. No simultaneous enhancement of HCMV and HIV-1 expression was observed in the dually infected cell cultures. Major immediate-early proteins of HCMV were necessary for enhancement of HIV-1 replication, and interleukin-6 production induced by HCMV and further increased by replicating HIV-1 synergized with these proteins to produce this effect. Permissive replication cycle of HCMV was induced by the HIV-1 tat gene product. We were unable to detect HIV-1 (HCMV) or HCMV (HIV-1) pseudotypes in supernatant fluids from dually infected cell cultures. Our results suggest that interactions between HIV-1 and HCMV in coinfected syncytiotrophoblast cells may contribute to the transplacental transmission of both viruses.
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PMID:Interactions between human immunodeficiency virus type 1 and human cytomegalovirus in human term syncytiotrophoblast cells coinfected with both viruses. 788 69

Cellular differentiation is thought to play an important role in the susceptibility of monocytic lineage cells to human immunodeficiency virus (HIV) infection as well as in their ability to support virus replication. In addition, virus replication in monocytes/macrophages has been demonstrated in vitro to be strongly modulated by several cytokines such as tumor necrosis factor alpha and granulocyte-macrophage colony-stimulating factor. The purpose of the present study was to investigate the interaction between cellular differentiation and cytokines in the regulation of HIV expression from chronically infected monocytic lineage cells. U1, a persistently HIV-infected promonocytic cell line, is characterized by low levels of virus expression which can be modulated by several cytokines. 1 alpha,-25-Dihydroxyvitamin D3 (Vit.D3), a well-known differentiating agent for myelomonocytic cells which has been previously reported to modulate HIV replication in other in vitro systems, induced maturation of U1 cells toward a macrophage-like phenotype, as demonstrated by the induction of the differentiation-associated cell surface markers CD14 and CD11b. Vit.D3-induced differentiation did not result in induction of HIV expression; however, when U1 cells were stimulated with tumor necrosis factor alpha in the presence of Vit.D3, a synergistic induction of cell differentiation and viral expression was demonstrated. In contrast, Vit.D3 suppressed the induction of HIV expression in U1 cells stimulated with gamma interferon, interleukin-6, and granulocyte-macrophage colony-stimulating factor, although synergy between Vit.D3 and these cytokines was observed in terms of cellular differentiation. These data suggest that differentiation of monocytic cells does not necessarily correlate with increased HIV expression.
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PMID:Effect of cellular differentiation on cytokine-induced expression of human immunodeficiency virus in chronically infected promonocytic cells: dissociation of cellular differentiation and viral expression. 788 4

Cells of monocytic lineage (Mo) persistently infected with human immunodeficiency virus (HIV) have been suspected to be a major reservoir for in vivo transmission of virus to susceptible target cells. Cellular events and mechanisms that upregulate viral gene expression in such cells are important issues. Because the traffic of such cells is central to biodistribution of HIV, we have explored the impact of interaction of endothelium with HIV-1-infected U1 promonocytic cells. Coculturing of U1 with human umbilical endothelial cells (HUVEC) for 24 to 72 hours in the absence of stimulation induced HIV-1 p24 biosynthesis significantly. Antibody-blocking experiments indicated that CD11/CD18 integrins play a role in upregulation of HIV expression elicited by interaction with HUVEC. Engagement of CD11b/CD18 by adherence of U1 to surfaces coated with either the cognate ligand fibrinogen or monoclonal antibody specific for CD11b/CD18 also enhanced p24 biosynthesis. Furthermore, endothelial cells were found to constitutively synthesize and secrete soluble factors that enhanced HIV-1 synthesis. The enhancing factors, of estimated size 10 to 45 kD, were induced in HUVEC to high levels by monokines or by lipopolysaccharide, resulting in markedly enhanced HIV-1 expression by U1. These endothelial cell-derived HIV-1-enhancing factors consist of, among others, interleukin-6 (IL-6), IL-1 beta, and granulocyte-macrophage CSF (GM-CSF). Our results suggest that activation of HIV biosynthesis in infected Mo via interaction with endothelium may impact significantly on the tissue distribution and pathogenesis of HIV infections.
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PMID:Upregulation of human immunodeficiency virus-1 in chronically infected monocytic cell line by both contact with endothelial cells and cytokines. 791 48

Increased interleukin-6 (IL-6) production and expression by malignant cells of the IL-6 receptor has been evidenced in a subgroup of non-Hodgkin's lymphomas, suggesting that this cytokine plays a role in lymphoma growth and in B clinical symptoms. In this study, the effect of the administration of an anti-IL-6 monoclonal antibody (MoAb) was analyzed in 11 patients seropositive for human immunodeficiency virus-1 and suffering from an immunoblastic or a polymorphic large-cell lymphoma. The antibody (BE-8, 10 to 40 mg/day) was administered for 21 days. Neutralization of in vivo IL-6 effect was assessed by monitoring C-reactive protein levels in the serum. In 5 patients, the lymphoma progressed during treatment. Among them were the 2 patients in whom endogenous IL-6 effect was not neutralized. Five patients experienced a stabilization, and 1 a partial remission. This effect on lymphoma growth lasted for 8 to 28 weeks. The anti-IL-6 MoAb had a clear effect on lymphoma-associated fever and cachexia. The mean body weight increase was 1.4 +/- 0.5 kg between day 1 and day 21, and reached 12 kg in 120 days in 1 patient who received three courses of treatment. Side effects were a consistent but moderate thrombocytopenia, and an occasional and moderate decrease of neutrophil counts. Immunization against the MoAb was observed in only 2 patients. These results indicate that in some cases of lymphomas growth of malignant cells may be partially IL-6-dependent and that neutralizing endogenous effect of IL-6 completely abrogates B clinical symptoms.
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PMID:Administration of an anti-interleukin-6 monoclonal antibody to patients with acquired immunodeficiency syndrome and lymphoma: effect on lymphoma growth and on B clinical symptoms. 791 67

Endothelin (ET) produced by endothelial cells has recently been found to be a potent vasoconstricting hormone. In this report, ET is shown to be a potent stimulator of interleukin-6 (IL-6) production by rat bone marrow (BM)-derived stromal cells. It was also shown that ET increased the level of mRNA for IL-6 in these cells. The two types of ET receptor (R), ETAR and ETBR, were shown to be expressed on both BM-derived stromal cells in culture and ex vivo in BM tissue, suggesting that ET works as a physiologic stimulator of IL-6 production in the BM. It was shown that ETAR is coupled to phospholipase C activation, leading to the production of inositol 1,4,5-trisphosphate (IP3) and 1,2-diacylglycerol (DAG) as second messengers in BM-derived stromal cells. This was corroborated by data showing that IL-6 production in these cells was induced by combined stimulation with ionomycin and phorbol myristate acetate, thereby bypassing the effects of IP3 and DAG, respectively. This is the first report on the hormonal regulation of IL-6 production by BM stromal cells, indicating that hematopoiesis is subject to endocrinologic regulation under physiologic conditions. ET has recently been reported to be produced by macrophages in response to bacterial lipopolysaccharide and human immunodeficiency virus-1 glycoprotein 120. These facts, taken together with our findings, raise the possibility that ET shares the same role of IL-1 as a local cytokine, mediating an intercellular signal between macrophages and BM stromal cells in response to bacterial or viral stimulation.
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PMID:Stimulation of interleukin-6 production by endothelin in rat bone marrow-derived stromal cells. 791 71

The simian immunodeficiency virus SIVsmmPBj14 (SIV-PBj14) is an atypical lentivirus that causes acute disease and death in pig-tailed macaques and in vitro replicates efficiently in resting macaque lymphocytes and activates and induces proliferation of lymphocytes. The present study was conducted to test the hypothesis that production of large quantities of SIV-PBj14 induces widespread immune activation and elaboration of cytokines which lead directly to the death of infected pig-tailed macaques. Following intravenous inoculation of pig-tailed macaques with SIV-PBj14, acute disease developed and was characterized by high levels of plasma viremia, p27gag antigenemia, tumor necrosis factor alpha, and interleukin-6 (IL-6). All animals died within 10 days of infection, at which time some animals had as many as 100% CD4+ cells in the periphery and lymphoid tissues infected. During the last few days before death, titers of infectious virus in blood increased as much as 10(5)-fold. By using dual-label immunofluorescence assays for detection of cell surface activation markers, both CD4+ and CD8+ lymphocytes were shown to express the IL-2 and transferrin receptors following either in vivo or in vitro infection with SIV-PBj14. Furthermore, in vitro infection of quiescent macaque lymphocytes by SIV-PBj14 was accompanied by proliferation of both CD4+ and CD8+ lymphocyte subsets, as measured by incorporation of [3H]thymidine. Increases in numbers of activated lymphocytes and levels of proinflammatory cytokines in plasma coincided with increased amounts of detectable virus in vivo. Clinical signs of disease and pathologic findings were most consistent with death from a shock-like syndrome, in which acute-phase inflammatory cytokines are known to play a major role. Tumor necrosis factor alpha, IL-2, and IL-6 were detected in some cultures infected with SIV-PBj14, but this finding was not consistent. When cytokines were detected, their concentrations were essentially no different from those found in control cultures infected with SIVsmm9, a prototypic strain from which SIV-PBj14 was derived. The in vivo results suggest a synergistic cycle of activation of lymphocytes and monocytes, elaboration of cytokines, and virus production that accelerates uncontrolled and culminates in death. The observed correlations between in vivo and in vitro activation events following SIV-PBj14 infection validate the use of in vitro studies to clarify lentivirus-lymphocyte interactions that may contribute to the virulence of SIV-PBj14.
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PMID:Immune activation and viral burden in acute disease induced by simian immunodeficiency virus SIVsmmPBj14: correlation between in vitro and in vivo events. 805 36

Antibodies against lymphocytes have been shown in human immunodeficiency virus (HIV)-infected patients, but their relevance in the pathogenesis of acquired immune deficiency syndrome (AIDS) remains controversial. We investigated increased levels of lymphocyte surface Ig and antibodies against CD4+ T cells in the plasma. The relationship to CD4 cell depletion and serological parameters were analysed. A three-colour flow cytometric method was used to detect surface Ig on the surface of patients' cells and antibodies in the plasma of the patients. We observed a high percentage of patients with increased surface Ig on CD4+ T cells (94%-47/50). Antibodies in the plasma reacting with healthy donors' CD4+ T cells were detectable in 72% (23/32) of the patients. CD4 cell-surface Ig correlated well with surface Ig on different T-cell subpopulations but not with increased surface Ig on B cells. Only one control showed elevated surface Ig, plasma antibodies against lymphocytes were not detectable. Surface Ig levels of CD4+ T cells were closely associated with the CD4 cell number in HIV-infected patients of all stages of disease (r = -0.67, P = 0.00005). Other lymphocyte subsets' surface Ig did not show a significant association to CD4 cell depletion. Surface Ig and antibodies against CD4+ T cells were not related to levels of beta 2-microglobulin, p24 antibodies or interleukin-6 (IL-6), and did not depend on hypergammaglobulinaemia. In conclusion surface Ig on CD4+ T cells is likely to have an autoantibody origin. The high prevalence and association to CD4 depletion support the view that autoimmune phenomena could be involved in the pathogenesis of AIDS.
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PMID:Relationship of antibodies against CD4+ T cells in HIV-infected patients to markers of activation and progression: autoantibodies are closely associated with CD4 cell depletion. 810 20

The immune response of normal human peripheral blood mononuclear cells (PBMC) after stimulation with human immunodeficiency virus-1 (HIV-1) antigens plus Leishmania donovani promastigotes in vitro was investigated. HIV-1-antigen stimulation of PBMC did not induce the intracellular accumulation of interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-alpha), or interferon-gamma (IFN-gamma). However, cells stimulated with L. donovani antigens exhibited the production of IL-6 and TNF-alpha, but not IFN-gamma. Furthermore, co-stimulation of PBMC with HIV-1 antigen plus L. donovani resulted in the intracellular accumulation of IL-6 and TNF-alpha comparable to that of cells that were activated with L. donovani antigen alone. Heat-inactivated HIV-1 antigen did not appear to induce or suppress cytokine production by PBMC. However, the same HIV antigens did suppress L. donovani-induced proliferation as well as PPD-induced proliferation in a dose-dependent fashion. Elevated levels of serum cytokines have been demonstrated in patients with HIV infection indicating their role in the pathogenesis of HIV-associated immunosuppression. The results may partially support the idea that the abnormally increased cytokine levels in the sera of HIV-infected subjects is due to the various opportunistic pathogens that these patients contract, rather than a response to HIV antigens. As cytokines have been shown to up-regulate HIV replication, the data suggest a role for opportunistic infections in cytokine-induced transactivation of HIV-1 and disease progression.
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PMID:HIV-1 inhibits Leishmania-induced cell proliferation but not production of interleukin-6 and tumour necrosis factor alpha. 814 97


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