Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report the case of a 63 year-old female who presented with a seven-year history of epigastric pain and a sudden overall deterioration. Gastroscopy demonstrated inflammatory aspect and ulceration in the antrum and fundus. Histology showed a lymphocytic infiltrate consistent with low grade mucosa-associated lymphoid tissue lymphoma and cytomegalovirus gastritis. There was no evidence of Helicobacter pylori infection. Other investigations demonstrated two pulmonary foci consistent with lymphomatous infiltration and a reduced CD4 + T-lymphocyte count (85/mm3). Other screening tests including HIV serology were negative. This case of idiopathic CD4 lymphopenia, in conjunction with the other rare cases in the literature, allows us to reevaluate this condition and its unusual clinical presentation with two opportunistic pathologies.
 ...
PMID:[Multifocal MALT lymphoma and acute cytomegalovirus gastritis revealing CD4 lymphopenia without HIV infection]. 1021 14

To investigate the role of apoptosis in the early phase of HIV infection, we used macaques infected with simian immunodeficiency virus strain mac (SIVmac) as a primate model and examined sequentially the characteristics of apoptosis of lymphocytes in peripheral blood mononuclear cells (PBMCs) and lymph nodes in the early phase of SIVmac infection. Five macaques infected with a pathogenic strain of SIV, SIVmac239, were analyzed during the first 4 weeks after infection. Peripheral CD4+ and CD8+ cells transiently decreased at 1 week postinfection. The percentage of apoptotic cells in cultured PBMCs increased from about 2 weeks postinfection. The number of apoptotic cells in lymph node sections was higher on days 13 and 28 postinfection than before infection and on day 5 postinfection. Fas antigen expression on peripheral lymphocytes was upregulated from day 8 postinfection. These results indicate that apoptosis is induced about 2 weeks after SIVmac239 infection, following the upregulation of Fas antigen expression on lymphocytes. Since apoptosis was induced about 1 week after the decrease in peripheral CD4+ and CD8+ cell counts, it appears that the apoptosis induction does not play an important role in the transient lymphopenia in the early phase of SIVmac infection. In macaques infected with a nonpathogenic derivative of SIVmac239, SIVmac delta nef, apoptosis of lymphocytes was induced as it was in SIVmac239-infected macaques, but to a lesser degree, suggesting a correlation between the extent of apoptosis induction in lymphocytes in the early phase of SIVmac infection and the pathogenicity of SIVmac.
 ...
PMID:Sequential analysis of apoptosis induction in peripheral blood mononuclear cells and lymph nodes in the early phase of pathogenic and nonpathogenic SIVmac infection. 1035 68

Drug-induced lymphopenia is a common adverse event. Some drugs, in particular those used in the treatment of malignancies and autoimmune diseases, inevitably affect the percentages and proportions of lymphocytes in the peripheral blood. Some other drugs exert only minor effects and their clinical relevance cannot be established with certainty. Most cytotoxic and immunosuppressive drugs affect CD4+ T cells more profoundly. Since their regeneration seems to be slower than that of CD8+ T cells, the frequent occurrence of CD4+ lymphopenia may merely reflect this phenomenon. As in HIV infection, critically low numbers of CD4+ cells, irrespective of the cause, predisposes to opportunistic infections. There is no such critically low value for CD8+ cells, and their essential role in various pathological conditions should also be established.
 ...
PMID:Drug-induced lymphopenia: focus on CD4+ and CD8+ cells. 1045 78

Anatomo-pathological correlation in a case of systemic talc granulomatosis affecting lungs, pleura, liver, spleen and mesenteric lymph nodes resulting in pulmonary arterial hypertension and cor pulmonale is described. The patient, a 26-year-old male HIV-negative intravenous drug addict had no lymphopenia or any histopathologic findings at necroscopy compatible with AIDS, despite of a chronic high-risk behavior favoring this illness.
 ...
PMID:[Systemic talc granulomatosis in a HIV-negative intravenous drug addict]. 1051 62

An HIV-negative woman with chronic lymphopenia related to past sarcoidosis situated in the bone marrow presented with an inflammatory lesion in the iliac region due to a localized Mycobacterium genavense soft tissue infection. The lesion resolved after 12 months of antibiotic therapy with clarithromycin, ethambutol and ciprofloxacin. The patient had no recurrence of the subcutaneous abscess during a follow-up period of 14 months after the end of the treatment.
 ...
PMID:Localized Mycobacterium genavense soft tissue infection in an immunodeficient HIV-negative patient. 1070 81

Acute HIV-1 infection depletes CD4(+) T cells in gut-associated lymphoid tissue (GALT). The failure of containment of local viral replication, and consequent CD4(+) T cell depletion, might be due to delayed mobilization of effector CD8(+) T cells or absence of functioning HIV-1-specific CD8(+) T cell effectors within GALT. No studies have addressed human intestinal HIV-1-specific CD8(+) T cell functions. We sought to determine whether functional HIV-1-specific CTL were present in GALT and whether the repertoire differed from HIV-1-specific CTL isolated from peripheral blood mononuclear cells. From three HIV-1-infected subjects, we isolated HIV-1-specific CD8(+) T cells expressing the mucosal lymphocyte integrin CD103 from GALT. These antigen-specific effector cells could be expanded in vitro and lysed target cells in an MHC class I-restricted manner. HIV-1-specific CTL could be isolated from both duodenal and rectal GALT sites, indicating that CD8(+) effectors were widespread through GALT tissue. The breadth and antigenic specificities of GALT CTL appeared to differ from those in peripheral blood in some cases. In summary, we found HIV-1-specific CD8(+) effector T cells in GALT, despite HIV-1-induced CD4(+) T cell lymphopenia. This suggests that HIV-1-specific CTL in gut tissue can be maintained with limited CD4(+) T cell help.
 ...
PMID:Characterization of HIV-1-specific cytotoxic T lymphocytes expressing the mucosal lymphocyte integrin CD103 in rectal and duodenal lymphoid tissue of HIV-1-infected subjects. 1079 91

Infection with atypical mycobacteria occurs mainly in patients with a compromised cellular immune system, in particular in those with a defective T cell or monocyte function. Here we analyzed the specific immune response of an adolescent HIV-negative patient with disseminated mycobacterium avium infection and fatal varizella zoster virus infection. The patient presented with dysplastic hematopoesis of all cell lineage's and a bicytopenia of erythrocytes and leukocytes, but a hematological malignancy could not be found. We found a peripheral lymphopenia and monocytopenia, as well as a lack of NK-cells and B-cells. Lymphocytes consisted of 95% T cells, which contained up to 40% of TCR gammadelta+CD4-CD8-T-cells (mainly TCR gamma9delta2), few monocytes and B-cells. Approximately 50% of CD3+ T-cells showed a CD57+ NK-like phenotype. Functional analysis of PBMC revealed a good antigen-specific T cell function if antigen-presenting cells were supplemented from a HLA-matched donor. Moreover, a strong M. avium specific cytotoxicity mediated by TCR alphabeta+T-cells could be found in vitro and even ex vivo. In contrast, NK-killing was absent. No evidence for a defect in IL-12 or IFN-gamma production and signaling were found. The data indicate that a strong alphabeta and gammadelta T cell immunity tries to compensate for a deficient monocyte and NK cell function in this patient.
 ...
PMID:Strong alpha beta and gamma delta TCR response in a patient with disseminated Mycobacterium avium infection and lack of NK cells and monocytopenia. 1084 41

Anemia, thrombocytopenia, and neutropenia are common manifestations in patients with human immunodeficiency virus infection that become more frequent and severe with progression from the asymptomatic state to acquired immunodeficiency syndrome (AIDS). Causes of anemia in AIDS include nutritional deficiencies, infection, and marrow suppression by antiretroviral drugs and by the disease itself. Autoimmune hemolysis and blood loss from gastrointestinal lymphoma or Kaposi sarcoma may also contribute. Granulocytopenia may be due to infection, autoimmunity, or bone marrow suppression by drugs or the immunodeficiency virus. Lymphopenia, the classic hallmark of the disease, typically affects T-helper cells first and worsens as the disease advances. Lymphopenia is a result of the direct cytopathic effects of the virus. Thrombocytopenia can occur from antibodies causing an idiopathic thrombocytopenic purpura-like state from bone marrow suppression or from thrombotic thrombocytopenic purpura. A prolonged partial thromboplastin time due to a coagulopathy caused by lupus anticoagulant causing has been described. A variety of malignancies occurs.
 ...
PMID:Hematological Effects of Human Immunodeficiency Virus Infection. 1088 19

This study shows that naive CD8 T cells can acquire characteristics of memory T cells in the absence of stimulation with specific Ag simply by the process of homeostatic proliferation under lymphopenic conditions. This Ag-independent T cell differentiation pathway did not result in up-regulation of early activation markers (CD69, CD25, CD71), but expression of several memory markers (CD44, CD122, Ly6C) increased progressively with successive divisions. These markers were then stably expressed, and these cells also became more responsive functionally to specific Ag. Thus, all "memory" phenotype T cells in an individual may not be true Ag-experienced cells and may include naive cells masquerading as memory cells. These findings are specially relevant in cases of disease or treatment-induced lymphopenia such as in HIV-infected individuals or transplant recipients. In addition, this study may have implications for autoimmunity because homeostatic proliferation of naive T cells requires interaction with self peptide plus MHC molecules.
 ...
PMID:Cutting edge: naive T cells masquerading as memory cells. 1092 49

Using an established SIV/HIV-C2/1-infected cynomolgus monkey model displaying stable CD4+ T cell depletion, the kinetics of apoptosis and the levels of expression of CD95 membrane-associated CD95L on lymphocytes were investigated to test the involvement of the CD95/CD95L system in CD4+ T lymphocyte loss in vivo. Rapid depletion of CD4+ T cells occurred up to 2 weeks after infection, with chronic CD4+ T lymphopenia thereafter. During the initial CD4+ T cell loss, which was accompanied by viraemia, about 90% of the peripheral CD4+ T cell subset underwent spontaneous apoptotic cell death during 24 h of culture. Increased expression of CD95 was observed on both CD4+ and CD8+ T cell subsets, with CD95 expression on CD8+ cells declining rapidly, but high CD95 expression being maintained on CD4+ cells. Since CD95L was expressed on CD8+ T cells, B cells and to a lesser extent on CD4+ T cells, this suggests that CD95-mediated apoptosis might be controlled in an autocrine/paracrine fashion.
 ...
PMID:Induction of CD95 ligand expression on T lymphocytes and B lymphocytes and its contribution to apoptosis of CD95-up-regulated CD4+ T lymphocytes in macaques by infection with a pathogenic simian/human immunodeficiency virus. 1112 44


<< Previous 1 2 3 4 5 6 7 8 9 10