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

Stimulation of T-lymphocytes derived from some patients with common variable immunodeficiency (CVID) syndrome results in defective proliferation. The underlying mechanism is related to the inability of stimulated cells to secrete IL-2 while the expression of IL-2 receptor (IL-2R) is normal. We have identified a patient whose peripheral T-cells failed to proliferate and secrete IL-2 upon stimulation. The addition of recombinant IL-2 restored proliferation. The defect did not seem to be caused by accessory cell failure since the patient's adherent cells produced IL-1 and IL-6, and addition of allogeneic irradiated cells did not induce proliferation. Stimulation of CVID T-cells with phorbol esters and Ca2+ ionophore induced both IL-2 secretion and proliferation, indicating the absence of a defect in the transcription and/or translation of the IL-2 gene. The patient's T-cells expressed high levels of CD3. The majority of T-cells expressed the CD38 molecule which is normally found on thymocytes or activated T-cells but not peripheral blood T-cells and HLA-DR, another activation marker. However, CD25 (the IL-2R) and CD1, a marker of more immature thymocytes, were not expressed. Finally, the patient's cells were sensitive to an in vitro corticosteroid treatment. The possibilities that this patient's T-cells represent anergic T-cells or not fully matured thymocytes are discussed.
 ...
PMID:An unusual T-cell surface phenotype in vivo correlates with the failure to proliferate and produce IL-2 in vitro in a patient with common variable immunodeficiency. 128 May 40

Evidence of an acquired T cell-specific deficiency distinct from acquired immunodeficiency syndrome (AIDS) in a 63-yr-old Japanese female is provided. Recently, this patients suffered from primary invasive pulmonary aspergillosis. Skin tests to purified protein derivative of tuberculin (PPD) and Aspergillus antigens were negative. Upon admission to our hospital, her lymphocytes were exclusively unresponsive to T cell mitogens (concanavalin A, phytohemagglutinin, and OKT 3). The level of cells defined by monoclonal antibodies (CD1, CD2, CD3, CD4, WT31, and CD5) was less than 3%. In contrast, no decrease in the number of red blood cells, platelets, neutrophils or B cells was apparent. Five years ago, the patient had a normal white blood cell and lymphocyte count. However, over the following 4 yr, she developed lymphopenia. With medication, her pulmonary disease recovered, while lymphopenia still continued. The levels of immunoglobulins, complements and enzyme activities (adenosine deaminase and purine nucleoside phosphorylase) were normal. Moreover, several tests for HIV (ELISA and Western bolt) were negative suggesting that the T cell-specific deficiency was not a congenital immunodeficiency or AIDS but rather a new type of acquired immunodeficiency.
 ...
PMID:Acquired T cell specific deficiency other than acquired immunodeficiency syndrome (AIDS). 156 29

To correlate the intrinsic cellular immunodeficiency, which is a major cause of increased susceptibility to polytopic infections in Down syndrome (DS) patients, with the histologic abnormalities observed in the thymus of these patients, we have studied thymus fragments and thymocyte cell suspensions from 15 non-institutionalized DS subjects. Comparing to the control age-matched samples, a reduced thymic cortex and a distinct depletion of CD1-positive (+) cells was observed by immuno-histologic examination. The phenotypic analysis of unselected thymocytes showed a significant reduction of CD3+, CD1+, CD4+, and CD8+ cells. When the total thymocyte population was separated into 10 fractions, using a continuous Percoll density gradient, a difference in cell distribution was observed. DS thymuses are almost devoid of high-density thymocytes (fractions 6-9) while more than 75% of the cells were recovered in the lightest 3 fractions (Frs). In addition, these thymuses were characterized by a marked depletion of CD1+ cells and by a conspicuous reduction of CD3+ cells normally present in the high-density Frs. On the other hand, the lightest 3 Frs of DS subjects were enriched in low-density CD1+ cells. Although enriched in these cells, normally characterized by a high mitotic activity, Fr1 DS thymocytes showed a reduced spontaneous proliferative capacity. When the expression of T cell receptor alpha- and beta-subunits was studied, the percentages of cells stained with anti-alpha and anti-beta antisera were found to be reduced in DS unfractionated thymocytes. The reduced number of high-density CD1+ thymocytes associated with a reduced spontaneous proliferative activity of low-density CD1+ thymocytes suggests that in DS thymuses there is a deficient expansion of immature T cells, resulting in a reduction of the various thymocyte subpopulations, including the thymocyte pool which differentiates into functionally mature T cells expressing the alpha-beta T cell receptor.
 ...
PMID:Intrathymic deficient expansion of T cell precursors in Down syndrome. 214 51

The resting human microglia have previously been shown to be cells of dendritic morphology expressing class II MHC antigens and macrophage specific antigens by immunocytochemical techniques. To examine the relationship between the microglia and the family of dendritic antigen presenting cells (APC), normal white matter from eight normal adults with no neurological disease at autopsy was examined by immunocytochemical techniques to localize antibodies to leukocyte common antigen (LCA), HLA-DR, CD1 (T6), CD4 (T4), and glial fibrillary acidic protein. In addition, enzyme histochemical staining for ATPase, non-specific esterase (NSE), and acid phosphatase (ACP) was performed. The normal microglia are ATPase +ve, NSE -ve, ACP -ve, HLA-DR +ve, LCA +ve, CD1 (T6) +ve and weakly CD4 (T4) +ve. This specialized phenotype closely resembles that of Langerhans cells and suggests that microglia are not simply quiescent phagocytes, but may have a primary role as microenvironmentally specialized APC. The finding of weak anti-CD4 (T4) immunoreactivity supports suggestions for a central role for this cell in infection of the central nervous system by human immunodeficiency virus type 1.
 ...
PMID:Microglial cells in human brain have phenotypic characteristics related to possible function as dendritic antigen presenting cells. 253 Mar 24

The majority of lymphomas that develop in human immunodeficiency virus type 1 (HIV-1) positive patients have a B-cell phenotype, with few reported cases of T-cell lymphoma. Within the latter group, those that have been comprehensively phenotyped had a mature helper T-cell phenotype (CD4+). We report, for the first time, an HIV-1 positive patient with a precursor T-cell lymphoma (CD7+,CD1-,CD3-,CD4-, and CD8-). T-cell receptor beta and gamma genes were in the germline configuration and integration of HIV-1 DNA could not be detected in the lymphoma cell genome.
 ...
PMID:Precursor T-cell lymphoma associated with human immunodeficiency virus type 1 (HIV-1) infection. First reported case. 278 49

A polyclonal T-cell receptor complex (TCR) expression defect (as detected with monoclonal antibody WT31) has been found in two children belonging to an otherwise healthy Spanish family. One of the sibs (V, who had been vaccinated with attenuated poliomyelitis virus) showed clinical signs of immunodeficiency with an autoimmune syndrome, but the other (older) sib (D, vaccinated with attenuated rubella, measles, mumps, and poliomyelitis viruses) has been symptomless throughout life. In contrast to both sibs' normal expression of other peripheral leucocyte markers, as measured by flow cytometry (including CD1, CD2, CD4, CD8, and CD16), only about 6% of CD2+ polyclonal T cells expressed surface antigen-specific T-cell receptor (Ti/WT31), and only about 23% weakly expressed surface CD3 determinants. On the remaining CD2+ T cells in each sib the expression of Ti and CD3 was undetectable; the defect in CD3 expression is very likely secondary to the defect in Ti expression. Natural killer (NK) activity was not increased in any of the sibs, ruling out a high content of NK cells among their CD2+ lymphocytes. Functional data indicate that CD3-mediated T-cell activation with anti-CD3 monoclonals and Ti-mediated responses to allogeneic and tetanus toxoid antigens were severely depressed, whereas activation via CD2 was normal in the T lymphocytes of both sibs. Genes encoding for Ti alpha, beta, and gamma chains did not show major alterations by southern blot analysis, and polyclonal beta chain genes rearrangements were detected in both children's T-cell blasts. Family clustering suggests a genetic pathogenesis, but linkage to HLA or other blood group markers has not been found. Sib V had a concomitant autoimmune disease and died after a severe autoimmune haemolytic anaemia, indicating a relationship between the TCR and generation of autoimmune clones. However, the resistance of both individuals to infection and to vaccination with attenuated viruses, and the fact that sib D has been symptomless to date questions the relative importance of the TCR in the immune response against infection, and suggests that alternative T-cell activation pathways and non-specific defence mechanisms (external surfaces--bound and/or cellular) may suffice under certain circumstances.
 ...
PMID:An in vivo functional immune system lacking polyclonal T-cell surface expression of the CD3/Ti(WT31) complex. 296 74

To correlate the histologically observed thymic abnormalities with the cellular immunodeficiency found in Down's syndrome (DS), thymus fragments and thymocyte suspensions from 14 noninstitutionalized DS subjects were studied. Histologic examination and immunohistologic studies using an anticluster of differentiation (CD) 1 monoclonal antibody showed a contracted cortex due to cortical thymocyte depletion. When DS unselected thymocytes were phenotyped, a significant reduction of CD3-, CD1-, CD4-, and CD8-positive cells was found as compared to controls. To evaluate if the deficient expression of these markers was due to the reduction of thymocyte subsets identifiable on the basis of their physical properties, we separated DS unselected thymocytes into 10 fractions by continuous Percoll density gradient centrifugation. DS thymuses were almost completely devoid of high density thymocytes. Since in normal thymus, these cells correspond to small CD1+, CD4+, CD8+, and 50% CD3+ cortical thymocytes, their absence may explain the unrestricted reduction of markers on DS unfractionated thymocytes. Furthermore DS thymuses appeared to be enriched in CD1+ first fraction (Fr1) low density thymocytes of the Percoll gradient. Fr1 CD1+ cells constitute the main spontaneously proliferating pool in normal human thymus. When the spontaneous proliferating activity of DS Fr1 was compared to that of the control, a significant reduction was observed. This reduction associated with the absence of high density thymocytes, with the reduction of cells expressing alpha- and beta-chains of the T cell receptor and in conclusion with the lymphocyte depletion, suggests that in DS thymuses there is a deficient expansion of immature T cells resulting in a reduction of the various thymocyte subpopulations, including the thymocyte pool able to differentiate into functionally mature T cells.
 ...
PMID:Alterations in thymocyte subpopulations in Down's syndrome (trisomy 21). 297 89

The presence of proteins (p17 and p24 core proteins, gp41 envelope protein) and mRNA (gag/pol and env gene segments) of human immunodeficiency virus type-1 (HIV-1) was analyzed on frozen tissue sections of lymph nodes from HIV-1 infected individuals. Thirty-one lymph nodes were categorized in the stages of follicle hyperplasia (n = 18), follicle degeneration (n = 5), and total depletion (n = 8). The follicle dendritic cells in germinal centers showed the presence of core proteins and, to a lesser extent, gp41. The staining patterns, being similar to those of immunoglobulins, suggested that they occur in the form of immune complexes. In addition there were solitary cells expressing viral protein, in particular gp41, and mRNA. The number of mRNA-positive cells was very low: about five positive cells were observed in a tissue section with about ten (hyperplastic) follicles. HIV-1-mRNA-positive cells were observed both in follicles and interfollicular areas and showed no differences between various stages. The extent and intensity of distinct HIV-1 proteins and HIV-1-mRNA gene segments in follicles were significantly correlated, as was their presence in interfollicular areas. No significant correlation was found between the presence of HIV-1 components in follicles and in interfollicular areas. This indicates that processes involving HIV-1 components occur in a segregated manner in both lymph node compartments. The presence of HIV-1 components did not correspond to any clinical classification (CDC criteria), nor to other histochemical characteristics. An exception was the correlation between gp41-positive cells and CD1-positive interdigitating cells in the interfollicular areas.
 ...
PMID:Expression of RNA and antigens of human immunodeficiency virus type-1 (HIV-1) in lymph nodes from HIV-1 infected individuals. 305 4

CD1 monoclonal antibodies were assayed on peripheral blood mononuclear leukocytes (PBML) of type 1 human immunodeficiency virus (HIV1)-infected patients using immunogold technique. Using IOT6 monoclonal antibody, a significant increase of the CD1 positive cells per microliter of blood was found in acquired immunodeficiency syndrome (AIDS) and AIDS-related complex (ARC) patients (265 +/- 34/microliters, n = 44 and 491 +/- 64/microliters, n = 36, respectively) as compared to controls (108 +/- 11/microliters, n = 43, P less than 0.001). These findings were confirmed with four other CD1 monoclonal antibodies in six patients. Characterisation of these CD1 positive cells showed that they were double stained with either CD4 or CD8 monoclonal antibodies. Moreover, cytochemical analysis of these cells showed the absence of myeloperoxidase activity and ultrastructural examination did not reveal Birbeck granules, well known to characterise the Langerhans cells. Further investigations are warranted to assess the biological and clinical relevance of these findings.
 ...
PMID:Increased CD1-positive cells in peripheral blood of AIDS and ARC patients. 325 82

The antigenic phenotype of human villous stromal macrophages (M phi s) from first and third trimester placentas was analyzed using a large number of monoclonal antibodies (MAbs) to monocyte (Mo)/M phi-associated cell membrane determinants. The purpose of this study was to investigate M phi phenotypic heterogeneity to create a database for the correlation of M phi phenotype with specific immunologic functions. The results showed that villous stromal mononuclear cells express many cell surface antigens found on Mo and M phi s and that they are morphologically diverse, ranging in appearance from classic Hofbauer cells to spindle-shaped cells with long cytoplasmic processes. Villous stromal M phi s were the numerically dominant cell type in this structure and exhibited some major phenotypic differences from M phi s in other tissues. Comparison of first- and third-trimester placentas revealed variation in antigen expression with increasing gestational age, in particular of class II major histocompatibility complex (MHC) determinants: HLA-DR and HLA-DP antigen density was low on first-trimester villous M phi s and much higher on third-trimester M phi s while HLA-DQ was undetectable in the first trimester but present on cells in third trimester placentas. The CD1 (T6) antigen, found on Langerhans (LH) cells and cortical thymocytes, was detected on villous M phi s by two thirds of the MAbs directed against different epitopes on this determinant. Furthermore, comparison with similar studies of lymphoid tissues showed that villous M phi s and dendritic cells share the expression of a number of other cell surface antigens. Finally, it was shown that M phi s in first- and third-trimester villi exhibit strong reactivity with MAbs (Leu 3a,b) to the CD4 antigen that serves as the receptor for the human immunodeficiency virus (HIV), suggesting that these cells may be a portal of entry or reservoir for this virus in the fetuses of pregnant, HIV+ women.
 ...
PMID:The phenotype of human placental macrophages and its variation with gestational age. 326 59


1 2 3 Next >>