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)

A 24 year old male with a history of eczema, recurrent mild infections, and thrombocytopenia consistent with the Wiskott-Aldrich syndrome (WAS) presented with a mediastinal mass, generalized lymphadenopathy, splenomegaly, and severe thrombocytopenia. Studies of immune function including immunoglobulin levels and T-cell subsets were normal. Furthermore, his T lymphocytes proliferated normally in response to phytohemagglutinin, concanavalin A, and the combination of neuraminidase/galactose oxidase. However, their proliferative responses to anti-CD43 antibody and periodate were diminished, consistent with the clinical diagnosis of WAS. An initial inguinal lymph node biopsy surprisingly revealed Kaposi sarcoma. However, following splenectomy to increase the platelet count, biopsy of the mediastinal mass revealed T-cell large cell lymphoma. Studies of biopsied tissue for the presence of Epstein-Barr virus and cytomegalovirus were negative, as were studies of blood, including the polymerase chain reaction, for the presence of the human immunodeficiency virus (HIV). This is the first report of Kaposi sarcoma arising in a patient with a congenital immunodeficiency syndrome. Although Kaposi sarcoma can arise in the face of the severe immunosuppression that follows allograft transplantation and in patients infected with HIV, we postulate that longevity in the face of mild immunosuppression was the major factor in the development of Kaposi sarcoma in this patient.
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PMID:Coincident Kaposi sarcoma and T-cell lymphoma in a patient with the Wiskott-Aldrich syndrome. 131 18

A cDNA encoding UDP-GlcNAc:Gal beta 1-3GalNAc-R (GlcNAc to GalNAc) beta 1-6GlcNAc transferase (EC 2.4.1.102), which forms critical branches in O-glycans, has been isolated by an expression cloning approach using Chinese hamster ovary (CHO) cells. Increased activity of this enzyme and the concomitant occurrence of the O-glycan core 2 structure [Gal beta 1-3(GlcNAc beta 1-6)GalNAc] has been observed in a variety of biological processes, such as T-cell activation and immunodeficiency due to the Wiskott-Aldrich syndrome and AIDS. Since CHO cells do not express this enzyme, CHO cell lines were established to stably express polyoma large tumor (T) antigen, which enables transient expression cloning. Because the antibody used was found to detect most efficiently the oligosaccharide products attached to leukosialin, the CHO cells were also stably transfected with leukosialin cDNA. By using this particular CHO cell line, a cDNA that encodes a protein determining the formation of the core 2 structure was isolated from an HL-60 cDNA library. The cDNA sequence predicts a protein with type II membrane topology, as has been found for all other mammalian glycosyltransferases cloned to date. The expression of the presumed catalytic domain as a fusion protein with the IgG binding domain of protein A enabled us to demonstrate unequivocally that the cDNA encodes the core 2 beta-1,6-N-acetylglucosaminyltransferase, the enzyme responsible for the formation of Gal beta 1-3(GlcNAc beta 1-6)GalNAc structures. No activity with this enzyme was detected toward the acceptors for other beta 1-6GlcNAc transferases.
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PMID:Expression cloning of a cDNA encoding UDP-GlcNAc:Gal beta 1-3-GalNAc-R (GlcNAc to GalNAc) beta 1-6GlcNAc transferase by gene transfer into CHO cells expressing polyoma large tumor antigen. 132 93

The Wiskott-Aldrich syndrome (WAS) is an X-linked disease characterized by eczema, thrombocytopenia, and profound immunodeficiency in affected males. While the etiology of the syndrome is currently unknown, abnormalities of CD43 have been described as a biochemical marker of the disease. Several investigators have demonstrated alterations in the expression of the CD43 surface antigen on WAS hematopoietic cells, noting either absence, decreased levels or changes in the characteristic molecular weight of the protein on the lymphocytes of affected patients. Biochemical studies have further indicated that glycosylating activity of specific enzymes which may post-translationally modify CD43 is altered in both T cells and Epstein-Barr-virus (EBV)-transformed B cells in WAS patients when compared to unaffected controls. Here we present data on cells derived from two males with a clinical diagnosis of WAS. Analysis of genomic DNA from the mothers of each of these patients (obligate carriers) showed a nonrandom X-chromosome inactivation pattern of nucleated blood cells, confirming the diagnosis of the X-linked syndrome. CD43 was characterized on peripheral blood lymphocytes and long-term EBV-transformed B cell lines, both to further analyze the molecular defects of WAS, as well as to attempt to generate a reproducible method for disease detection. Surprisingly, surface expression, molecular weight and two-dimensional gel analysis failed to demonstrated any reproducible differences in the CD43 expression, whether from disease or normal lymphocytes. Such results suggest possible heterogeneity of this syndrome.
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PMID:CD43 is expressed normally on Wiskott-Aldrich-derived lymphocytes. 133 89

Seven forms of X-linked (XL) immunodeficiency have been described (XL agammaglobulinemia, XL severe combined immunodeficiency [SCID], Wiskott-Aldrich syndrome, XL chronic granulomatous disease, XL hyper-IgM syndrome with low IgG and IgA, and XL lymphoproliferative syndrome), and properdine deficiency. Although there are (some) phenotypic variants, diagnosis is relatively simple on the basis of clinical, immunological, and genetic characteristics. We studied a family in which several males were affected by severe infections and whose pedigree suggested recessive XL inheritance of an immunodeficiency. Immunologic and genetic studies (X inactivation patterns in females and restriction fragment length polymorphism [RFLP] segregation) were performed in order to characterize the immunodeficiency. The propositus, a 5-yr-old boy, was found to have a severe and progressive T- and B-cell functional immunodeficiency characterized by defective antigen-specific responses. No lymphocyte subsets or membrane anomalies were detected and the immunodeficiency did not correspond to usual XL forms. Studies of DNA from two of the informative females, the mother and one sister revealed nonrandom X chromosome inactivation of T cells and, partially, B cells but not PMN, a pattern similar to that observed in XL SCID carriers. RFLP studies identified a haplotype segregating with the abnormal locus that may be localized in the proximal part of the long arm of the X chromosome. We thus report the characterization of a new XL immunodeficiency that may correspond either to another XL locus or to an attenuated phenotype of XL SCID.
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PMID:Genetic study of a new X-linked recessive immunodeficiency syndrome. 134 96

A unique case of a Chinese boy with Wiskott-Aldrich syndrome (WAS) associated with Takayasu's arteritis is reported. He had eczema, epistaxis and recurrent infections since early infancy and was found to have thrombocytopenia, negative delayed-type skin hypersensitivity, low T cell number and impaired lymphocyte proliferation to phytohaemagglutinin and concanavalin A. He had high normal serum immunoglobulin (Ig)G and IgA with low IgM and isohaemagglutinin. He presented with hypertensive encephalopathy at 5.5 years of age and an aortogram demonstrated abdominal aortic aneurysm with bilateral stenosis of renal arteries resulting in renovascular hypertension. His hypertension was difficult to control medically and autotransplant of his kidneys to the iliac arteries was performed, but he died in the immediate postoperative period. The relationship between immunodeficiency and collagen-vascular disease was discussed.
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PMID:Takayasu's arteritis associated with Wiskott-Aldrich syndrome. 135 86

B lymphocytes from patients expressing the X chromosome-linked immune deficiency disorder, Wiskott-Aldrich syndrome (WAS), fail to produce antibodies in response to stimulation with polysaccharides and other type-2 T cell-independent antigens. To investigate whether this abnormality reflects a defect in the signal transduction cascade normally triggered by ligation of surface immunoglobulin (sIg) on B cells, we have examined early signaling events induced by anti-Ig antibody stimulation of EBV B lymphoblastoid cell lines from WAS patients and healthy controls. Despite the expression of comparable levels of sIg and sIgM on WAS and control EBV B cells, WAS cells failed to manifest the increased proliferation in response to anti-Ig treatment observed in the control cell lines. WAS and control EBV B cells also differed in the magnitude of the change in cytosolic free calcium ([Ca2+]i) induced by sIg ligation; WAS cells showed either markedly diminished or no changes in [Ca2+]i levels whereas control EBV B cells consistently showed increases in [Ca2+]i. Anti-Ig-induced changes in inositol phosphate release were also markedly reduced in WAS compared with control cells. As protein tyrosine phosphorylation is thought to represent a proximal event in the activation of B cells, inducing increases in [Ca2+]i by virtue of tyrosine phosphorylation of phospholipase C (PLC)-gamma, profiles of protein tyrosine phosphorylation and expression of tyrosine-phosphorylated PLC-gamma 1 were compared between WAS and normal EBV B cells before and after sIg cross-linking. These studies revealed that in addition to defective mobilization of Ca2+, the WAS cells manifested little or no increase in tyrosine phosphorylation of PLC-gamma 1 or other intracellular proteins after sIg ligation. Together these results indicate the association of WAS with a defect in the coupling of sIg to signal transduction pathways considered prerequisite for B cell activation, likely at the level of tyrosine phosphorylation. The abnormalities observed in these early transmembrane signaling events in WAS EBV B cells may play a role not only in the nonresponsiveness of WAS patient B cells to certain T independent antigens, but also in the genesis of some of the other cellular deficits exhibited by these patients.
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PMID:Evidence for defective transmembrane signaling in B cells from patients with Wiskott-Aldrich syndrome. 140 Oct 74

The Wiskott-Aldrich syndrome is an uncommon X-linked recessive disease characterized by eczema, thrombocytopenia, and immunodeficiency. The clinical features begin early in life and include recurrent infections, bleeding, and severe eczema. Unless the condition is treated by bone marrow transplantation, the prognosis of Wiskott-Aldrich syndrome is grave, and premature death caused by sepsis, hemorrhage, or lymphoreticular malignancy is common. Although the biochemical defect responsible for the syndrome is not known, recent investigations with restriction fragment length polymorphisms have mapped the Wiskott-Aldrich syndrome locus to the proximal portion of the short arm of the human X chromosome (Xp11). The isolation of these DNA markers makes feasible both carrier detection and prenatal diagnosis of Wiskott-Aldrich syndrome and provides an important adjunct to the management of Wiskott-Aldrich syndrome for patients and their families. These genetic data, in conjunction with the recent identification of a specific O-glycosylation defect in lymphocytes from patients with Wiskott-Aldrich syndrome, present an opportunity for the eventual isolation of the Wiskott-Aldrich syndrome gene and identification of the underlying cellular defect. We review the clinical and laboratory features of this syndrome and summarize the new molecular and biochemical approaches that can be used in diagnosis, genetic counseling, and treatment.
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PMID:Wiskott-Aldrich syndrome: new molecular and biochemical insights. 140 1

The Wiskott-Aldrich syndrome (WAS) is a severe immunodeficiency and platelet deficiency disease arising from an X-linked defect. The disease is correctable by transplantation of hematopoietic stem cells, but the product of the defective gene is unidentified and the number of defects in patient blood cells is large. The current hurdle is the need to identify the early pathogenic event(s) that are the cause of other defects. As a step toward this goal, we have generated and examined a panel of interleukin 2-dependent allospecific T cell lines from peripheral lymphocytes of seven WAS patients and five normal individuals. WAS cell lines, like normal lines, undergo vigorous proliferation when challenged with specific allostimulant or with phorbol myristate acetate and ionomycin. Both normal and WAS T cell lines express cell surface molecules CD2, CD3, T cell receptor-alpha/beta, human histocompatibility leukocyte antigen class I, CD45 and CD11a, and varying ratios of CD4 and CD8, and are negative for natural killer cell and monocyte surface molecules. WAS T cell lines express CD43 (sialophorin/leukosialin) with molecular weight and in an amount comparable with normal T cell lines. WAS T cell lines thus do not express defects in CD43 (decreased amount, abnormal molecular weight), previously documented in WAS circulating lymphocytes. On the other hand, as detected by scanning electron microscopy, WAS cell lines exhibit severe morphological abnormalities, including decreased size and density of the microvillus surface projections. The morphological abnormalities of WAS T cell lines are similar to, or more extensive than, those previously reported for WAS peripheral lymphocytes, indicating that the generation of morphological (cytoarchitectural) defects is an early pathogenic event in this disease. The findings suggest that the gene that is defective in the WAS encodes a protein that normally functions to maintain or regulate the cytoskeletal structure of blood cells.
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PMID:T cell lines characterize events in the pathogenesis of the Wiskott-Aldrich syndrome. 151 49

The molecular bases of the X-linked immunodeficiency diseases remain largely undetermined. Two of the genes involved in these diseases have been isolated, namely the genes for X-linked chronic granulomatous disease and properdin deficiency, and substantial progress has now been made in identifying the genes which are defective in the other five diseases, Wiskott-Aldrich syndrome, X-linked severe combined immunodeficiency, X-linked agammaglobulinaemia, X-linked hyper-IgM and X-linked lymphoproliferative syndrome. We review here the nature of the diseases, progress made in identifying and isolating the genes involved and the prospects for improved prenatal detection, carrier status determination and treatment of these life-threatening conditions.
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PMID:The molecular basis of X-linked immunodeficiency disease. 152 25

The Wiskott-Aldrich syndrome (WAS) is an inherited disease involving defects of platelets (small size, severe thrombocytopenia due to accelerated destruction) and T lymphocytes (progressive immunodeficiency, lymphopenia). The best-characterized molecular defect is the deficiency and, in some cases, abnormal forms of the T-lymphocyte surface mucin molecule CD43; deficiency of the platelet surface mucin GPIb was observed previously in two of four patients. Neither of these defects is primary, since CD43 and GPIb are encoded by autosomal genes and the disease is X-linked. This study uses cellular biological approaches to explore the possibility that destruction of structurally defective WAS platelets, mimicked experimentally by sonication of normal platelets, plays a role by releasing protease and generating other cellular defects. We show that a protease of normal platelets, identified as Ca(2+)-dependent neutral protease (calpain), which is known to cleave platelet GPIb, also specifically cleaves CD43 on the surface of neighboring desialylated T lymphocytes. The identification of the CD43 cleaving protease was based on its requirement for Ca2+ and inhibition by leupeptin, but not by diisopropylfluorophosphate (DFP). The approximate site of CD43 cleavage was identified by the use of a rabbit antibody. Sensitivity of GPIb to calpain is shown to be sialylation-independent and that of CD43 to be sialylation-dependent, and these findings are explained in terms of molecular structures. These and previous findings are incorporated into a putative mechanism, which explains most of the defects in the WAS. The mechanism suggests that the primary defective molecule in the WAS is unlikely to be a surface glycoprotein, but rather a cytoplasmic molecule with a function in cytoskeletal interactions and/or calcium ion regulation and calpain activation.
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PMID:Effect of platelet calpain on normal T-lymphocyte CD43: hypothesis of events in the Wiskott-Aldrich syndrome. 155 70


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