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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Severe Combined Immunodeficiency (SCID) is a fatal disorder of infancy in which patients exhibit profound defects of both cellular and humoral immune function. Approximately 50% of patients with the autosomal recessive form of SCID have a genetically determined deficiency of the purine salvage enzyme adenosine deaminase (ADA). Prenatal diagnosis of SCID-ADA deficiency has been successful and detection of heterozygous carriers has been shown to be feasible. A mutation at the structural locus for ADA has been found in several cases but clinical heterogeneity indicates that genetic heterogeneity at the molecular level is to be expected. In vitro model studies and clinical course suggest that the pathophysiology may involve primarily an inhibition of T-cell maturation with lesser effects on B-cell maturation as well as "self-destruction" of differentiated cells following antigen stimulation. The culprit may be adenosine itself or one of its metabolites such as ATP or cAMP, which are elevated in these patients. Bone marrow transplantation remains the recommended mode of therapy but red cell transfusion may offer an alternative when bone marrow transplantation is not feasible. The finding that deficiency of the next enzyme in the purine salvage pathway, nucleoside phosphorylase, is also associated with an immune deficiency disorder suggests that integrity of the purine salvage pathway may be crucial for normal differentiation and function of immunocompetent cells in man.
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PMID:Adenosine deaminase deficiency and immunodeficiencies. 87 49

The occurrence of a deficiency of adenosine deaminase (ADA) activity in some patients with severe combined immunodeficiency suggests a possible relationship between the activity of ADA and the aberration of the immune system. To help delineate the function of ADA in the immune response we have examined its role in monocyte maturation. When incubated in vitro, peripheral blood monocytes transformed, within 3 days, to macrophagea as assessed by phase-contrast microscopy and an increase in the specific activity of the lysosomal enzyme acid phosphatase. The specific activity of ADA increased as much as ninefold, reaching a peak after the 1st day in culture, while the activities of other enzymes involved in the purine salvage pathway were not altered. Sucrose density ultracentrifugation of extracts prepared immediately after the isolation of monocytes revealed the presence of two forms of ADA with molecular weights of approximately 30,000 and 110,000. The increase in ADA specific activity during monocyte cultivation correlated with an increase in the activity of the smaller molecular species. A specific inhibitor ADA, erythro-9-(2-hydroxy-3-nonyl) adenine, prevented the increase in acid phosphatase activity, as well as the morphological changes associated with the monocyte maturation. These data suggest a role for ADA in monocyte to macrophage maturation. In view of the central role of macrophages in immune function, this observation may relate to the association of combined immunodeficiency and a deficiency of this enzyme.
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PMID:A role for adenosine deaminase in human monocyte maturation. 95 74

Rosette formation with mouse erythrocytes and other cell-surface markers were examined on lymphocytes from patients with a variety of primary immunodeficiency and lymphoproliferative disorders. Mouse erythrocyte rosette-forming cells and lymphocytes with surface immunoglobulins were regularly absent in patients with Bruton type agammaglobulinaemia, immunodeficiency and thymoma syndrome and severe combined immunodeficiency disease. However, they were present in normal or low numbers in patients with common variable immunodeficiency, selective IgA deficiency and ataxis telangiectasia. Lymphocytes from patients with acute lymphoblastic leukaemia Sezary syndrome and mycosis fungoides made no or few rosettes with mouse erythrocytes. Increased numbers of mouse erythrocyte rosette-forming cells were present in patients with chronic lymphocytic leukaemia and Waldenstrom's macroglobulinaemia. The significance of the mouse erythrocyte rosette as a B-cell marker in the analysis of primary immunodeficiency and lymphoproliferative disorders is discussed.
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PMID:Rosette formation with mouse erythrocytes. III. Studies in patients with primary immunodeficiency and lymphoproliferative disorders. 106 59

The quantitative studies of B lymphocytes in peripheral blood have been performed in various forms of primary and secondary immunodeficiency disease in man. X-linked agammaglobulinemia was found to comprise two sub-types, one lacking B-cell population, the other showing low numbers of B lymphocytes. The absence of B cells in severe combined immunodeficiency was corrected by marrow transplants in 3 children. Cases of DiGeorge syndrome and lepromatous leprosy showed an absolute increase in numbers of B lymphocytes in peripheral blood, probably a compensatory mechanism in the market deficit of T-cell population and function. The reconstitution of DiGeorge syndrome by fetal thymus transplant reversed the abnormally high percentage of B lymphocytes.
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PMID:B lymphocytes in primary and secondary deficiencies of humoral immunity. 108 58

Surface markers typical of T and B lymphocytes were present on varying proportions of peripheral blood lymphocytes from three infants with severe combined immunodeficiency disease. Despite this, functions mediated by T and B cells were either absent or very minimal in all three, including cell-mediated responses in vivo; the in vitro proliferative response to mitogens, allogeneic cells, or antigens; effector cell function in lymphocyte-antibody lymphocytolytic interaction assays; and in vitro synthesis of IgG, IgA, and IgM. In contrast, mononuclear cells from one of the infants were tested and found capable of lysing both human and chicken antibody-coated erythrocyte targets normally. Co-cultivation experiments with unrelated normal control lymphocytes failed to demonstrate suppressor cell activity for immunoglobulin synthesis in these infants. Augmentations of immunoglobulin production from 310 to 560% over that expected on the basis of individual culture data were noted in co-cultures of one of the infants' cells with two different unrelated normal control cells. These findings suggest that that infant may have had a T helper cell defect or that his T cells were unable to produce soluble factors necessary for B cell differentiation. The finding of cells with differentiation markers characteristic of T and B lymphocytes in each of these patients, though in variable quantities, is further evidence for heterogeneity among patients with the clinical syndrome of severe combined immunodeficiency and argues against the concept that their immunodeficiency was due to a stem cell defect.
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PMID:Heterogeneity of lymphocyte subpopulations in severe combined immunodeficiency. Evidence against a stem cell defect. 108 54

Because others had described a lack of the enzyme adenosine deaminase as associated with severe combined immunodeficiency, we surveyed kindreds with infants affected with such an immunodeficiency. Three infants in two families with severe combined immunodeficiency were found to have no detectable erythrocyte adenosine deaminase. Eleven family members heterozygous for adenosine deaminase deficiency were encountered among the first-degree relatives; adenosine deaminase deficiency and severe combined immunodeficiency were associated and inherited as autosomal recessive traits in both kindreds. Successful bone-marrow transplantation was carried out in two of these infants. Normal immunologic function was established in both children, but the deficiency of adenosine deaminase persisted in their erythrocytes. The enzyme deficiency did not impair the successful establishment of normal humoral and cellular immunity by transplants of bone-marrow cells from siblings who were either normal or heterozygous for adenosine deaminase deficiency.
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PMID:Severe combined immunodeficiency and adenosine deaminase deficiency. 108 83

Surface IgD on blood lymphocytes was studied in 10 normal adults and 24 patients with primary immunodeficiencies by direct immunofluorescence, together with surface immunoglobulins of the other classes and with spontaneous rosette formation with sheep erythrocytes. In the normal adults, 8% of the lymphocytes bore delta chains (the figures for mu chains being 11%) and, among the cells positive for mu and/or delta, 70% were mixed stained, 22% and 8% being single stained for mu and delta respectively. In 10 patients with sex-linked agammaglobulinemia or variable immuno-deficiency, practically no cells bearing surface immunoglobulins, including IgD, were detectable. A normal distribution of surface immunoglobulins, including the results of double labeling for mu and delta, was found in five other immunodeficiency patients in whom there was a block of the terminal differentiation of B lymphocytes into plasma cells. A new kind of block in the differentiation of the B cell line was observed in two patients affected with sex-linked severe combined immunodeficiency and variable immuno-deficiency respectively. They showed high figures for IgD-bearing lymphocytes, some of which carried simultaneously mu chains, contrasting with the absence of lymphocytes carrying IgM without IgD and of IgG- or IgA-bearing cells. The data obtained in several other patients with low figures for IgG- and IgA-bearing lymphocytes and a predominance of IgD-carrying cells with an excess of single producers for delta chains over single producers for mu chains suggest an analogous but incomplete maturation arrest.
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PMID:Immunoglobulin D-bearing lymphocytes in primary immunodeficiencies. 109 Jun 63

An in vitro system has been developed to elucidate the nature of the cellular defect in primary immunodeficiency diseases. Incubation, on human thymic epithelial monolayer cultures, of peripheral blood lymphocytes and bone-marrow cells from a child with documented severe combined immunodeficiency disease resulted in the appearance of a population of cells that formed rosettes with sheep erythrocytes. The same cell preparation permitted the synthesis of antigen-specific, complement-dependent antibodies after in vitro education, as demonstrated in a plaque assay system. In addition, thymic tissue from the same child gave morphologic and functional evidence of maturation when cultured in vitro. The experimental results suggest that in this case, lymphoid precursor cells were present in the bone marrow but failed to differentiate to functional maturity due to a defect in maturation of thymic tissue.
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PMID:Demonstration of an intrathymic defect in a case of severe combined immunodeficiency disease. 109 26

A qualitative study was made of the plasma immunoglobulins of a child with severe combined immunodeficiency. By immunoelectrophoresis an immunoglobulin with an abnormal electrophoretic mobility was detected. This protein possessed mu heavy chain determinants, gave no detectable reaction with antisera specific for light chains, was of a relatively small molecular size, and was probably not composed of subunits held together by easily reduced disulfide bonds. The light chains that were present in this patient's plasma had a homogeneous electrophoretic mobility. The patient's plasma also contained at least two other immunoglobulins whose antigenic identity could not be established. One of these was abnormal in its electrophoretic mobility. The presence of the abnormal protein with mu determinants in the plasma of the second unrelated child with a similar disease suggests that the detection of this protein may have implications for the diagnosis or classification of immunodeficiency diseases.
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PMID:A paraprotein in severe combined immunodefeciency disease detected by immunoelectrophoretic analysis of plasma. 110 15

Surface receptors on peripheral blood neutrophils and monocytes from normal and immunodeficient horses have been studied. Sheep erythrocytes (SRBC) coated with IgG, IgM, and complement but not IgG(T), readily bound to normal equine monocytes and neutrophils. More than 4000 molecules of IgG were required to sensitize each SRBC for adherence to monocytes, and more than 12,000 molecules were required for adherence to neutrophils. Young horses with a severe combined immunodeficiency had an almost total absence of lymphocytes, but normal numbers of monocytes and neutrophils. The number of receptors for immunoglobulin, complement, and phytolectin on monocytes and neutrophils from immunodeficient animals were similar to those on the cells of normal horses. Although the precursor cells of lymphocytes of horses with combined immunodeficiency appear to be defective, no defect in the other cellular products of the bone marrow were apparent.
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PMID:Surface receptors on neutrophils and monocytes from immunodeficient and normal horses. 112 40


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