Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085110 (SCID)
 11,041 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mutations in the gene encoding the common gamma chain (gammac) of interleukin receptors 2, 4, 7, 9, 15 and 21 result in X-linked severe combined immunodeficiency (SCID-X1). Classically, this disease is characterised by an absence of T and NK cells, and near normal numbers of functionally deficient B cells (B(+), T(-), NK(-) phenotype). Atypical phenotypes have also been described, but relatively little is known about the mechanisms by which the underlying mutations impair gammac-dependent interleukin receptor signalling to produce these disease variants. Here we describe a novel splice-site mutation resulting in the presence of near normal numbers of functionally deficient NK cells (B(+), T(-), NK(+) phenotype), in a SCID-X1 infant who was subsequently treated by gene therapy. The mutation, c.468+3A>C affecting the third base of intron 3 in the IL2RG gene, was shown to result in the production of two aberrantly spliced gammac mRNA species and reduction of correctly spliced message to trace levels, consistent with failure to detect gammac on the surface of B and NK cells by FACS analysis. The infant's genotype-phenotype correlation supports the hypothesis that interleukin 15 receptor-mediated signalling is preferentially retained as the amount of cell surface gammac becomes limiting. The possible implications for immunological reconstitution following gene therapy are also discussed.
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PMID:A novel splice-site mutation in the common gamma chain (gammac) gene IL2RG results in X-linked severe combined immunodeficiency with an atypical NK+ phenotype. 1510 87

We previously showed therapeutic efficacy of humanized anti-Tac (HAT), murine anti-Tac (MAT), and 7G7/B6 monoclonal antibodies, which recognize CD25, for human adult T-cell leukemia (ATL) in a murine model. In this study, we investigated the mechanism underlying the tumor-killing action mediated by these antibodies on an ATL model in nonobese diabetic/severe combined immunodeficient (SCID/NOD) wild-type mice that lack effective T and natural killer (NK) cells and in SCID/NOD Fc receptor common gamma chain knockout (FcRgamma-/-) mice. The ATL model was established by i.p. injection of human ATL cells (MET-1) into SCID/NOD wild-type or SCID/NOD FcRgamma-/- mice. HAT, MAT, and 7G7/B6 were given to the leukemia-bearing mice at a dose of 100 microg weekly for 4 weeks. The three antibodies inhibited the leukemia growth significantly in SCID/NOD wild-type mice, as monitored by serum levels of human beta2-microglobulin (P < 0.01), and prolonged survival of the leukemia-bearing SCID/NOD wild-type mice (P < 0.01) as compared with the control group. However, none of the antibodies manifested efficacy on the leukemia growth and survival of the SCID/NOD FcRgamma-/- mice bearing MET-1 leukemia. In a pharmacokinetics study, the blood concentrations of the radiolabeled antibodies decreased with time similarly in SCID/NOD wild-type and SCID/NOD FcRgamma-/- mice. Although NK cells may play a role in humans, in this murine model FcRgamma receptors on non-NK cells, such as polymorphonuclear leukocytes or monocytes, are required for the tumor-killing action of the antibodies directed toward CD25.
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PMID:Activating Fc receptors are required for antitumor efficacy of the antibodies directed toward CD25 in a murine model of adult t-cell leukemia. 1531 26

JAK3, a member of the Janus kinase family, has a crucial role in T-cell development and the homeostasis of the immune system because of its association with the common gamma chain (gammac) of cytokine receptors. Disruption of either JAK3 or gammac expression results in severe combined immunodeficiency disease. Thus, JAK3 has attracted significant attention in recent years as a target for therapeutic intervention in several immune-related diseases. Inhibitors of JAK3 have been developed that might act as either immunosuppressive agents in human organ transplantation or as immunomodulators in autoimmune disorders. We propose that targeting JAK3 offers alternative avenues for the development of new immunomodulatory strategies of therapeutic value. Furthermore, we believe that in addition to the tyrosine kinase domain of JAK3, where inhibitor design efforts are currently focused, non-catalytic regions of JAK3 might represent candidate targets for future drugs.
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PMID:Is JAK3 a new drug target for immunomodulation-based therapies? 1549 77

Cytokines are critical in regulating the development and function of diverse cells. Janus kinase 3 (Jak3) is a tyrosine kinase expressed in hematopoietic cells that associates with the common gamma chain (gammac) and is required for signaling for a family of cytokines including interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21; deficiency of either Jak3 or gammac results in severe combined immunodeficiency (SCID). While Jak3 is essential for lymphoid-cell development, the potential roles for Jak3 in regulating dendritic cells (DCs) were unclear. Herein, we show that although CD8+CD11c+ splenic DCs are absent in Jak3-/- mice, bone marrow-derived DCs developed normally in vitro from Jak3-/- precursor cells. In fact, the survival of Jak3-/- DCs was enhanced, and they expressed lower levels of proapoptotic proteins. Jak3-/- DCs exhibited normal antigen uptake and up-regulation of costimulatory molecules. However, Jak3-/- DCs produced more IL-12 and IL-10 in response to Toll-like receptor ligands, which correlated with enhanced T helper 1 (Th1) differentiation in vivo. In summary, Jak3 is not essential for DC development but unexpectedly appears to be an important negative regulator. These results may be relevant clinically for patients with SCID who have undergone hematopoietic stem cell transplantation and for patients who might be treated with a Jak3 inhibitor.
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PMID:Jak3 negatively regulates dendritic-cell cytokine production and survival. 1602 May 5

Gnotobiotic animals are highly valued for the study of infectious diseases wherein the clinical signs and lesions of disease can be directly related to host-pathogen interactions and not to the additive effects of environmental influences and other confounding factors. Gnotobiotic dogs have been used to study the pathogenesis of acquired immunodeficiencies associated with canine distemper virus (CDV). In recent years, the laboratory at OSU, in conjunction with University of Pennsylvania personnel have begun a series of long-term studies of dogs affected with the canine X chromosome-linked severe combined immunodeficiency (XSCID) syndrome. This fatal inherited defect is caused by mutation in the common gamma chain (IL2RG) gene and renders affected animals profoundly immunodeficient. XSCIDs dogs, raised within a gnotobiotic environment for up to 3 years remain clinically healthy and are, in every respect normal except for the persistent T-cell defect and the failure to develop lymph nodes. Bone marrow transplantation (unfractionated or enriched for CD34+ stem cells) is the treatment of choice for both the XSCID dogs and male human infants affected with this syndrome. In preliminary studies, we have shown that human CD34+ stem cells colonized XSCIDs-affected gnotobiotic dogs, migrated to the thymus and demonstrated post-thymic activation (CD45RA+ phenotype) in peripheral blood. While many issues are unresolved, these data suggest that, through the use of the gnotobiotic environment, xenotransplantation (human-to-dog) may yield a stable and immunologically functional human-dog chimera.
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PMID:Gnotobiotics and immunopathology: the use of the gnotobiotic environment to study acquired and inherited immunodeficiency diseases. 1611 40

Cytokines that use the common gamma chain gammac are critical for lymphoid development and function. Mutations of the IL-7 receptor, gammac, or its associated kinase, Jak3, are the major cause of human severe combined immunodeficiency. Although activated by IL-7, Stat5a/b (Stat, signal transducer and activator of transcription) have been thought to play limited roles in lymphoid development. However, we now show that mice completely deficient in Stat5a/b have severely impaired lymphoid development and differentiation. Absence of Stat5 also abrogates T cell receptor gamma rearrangement and survival of peripheral CD8(+) T cells. Thus, deficiency of Stat5 results in severe combined immunodeficiency, similar in many respects to deficiency of IL-7R, gammac, and Jak3.
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PMID:Stat5a/b are essential for normal lymphoid development and differentiation. 1641 96

CD30 is a member of the tumor necrosis factor receptor family. Overexpression of CD30 on some neoplasms versus its limited expression on normal tissues makes this receptor a promising target for antibody-based therapy. Anaplastic large-cell lymphoma (ALCL) represents a heterogeneous group of aggressive non-Hodgkin lymphomas characterized by the strong expression of CD30. We investigated the therapeutic efficacy of HeFi-1, a mouse IgG1 monoclonal antibody, which recognizes the ligand-binding site on CD30, and humanized anti-Tac antibody (daclizumab), which recognizes CD25, in a murine model of human ALCL. The ALCL model was established by intravenous injection of karpas299 cells into nonobese diabetic/severe combined immuno-deficient (SCID/NOD) wild-type or SCID/NOD Fc receptor common gamma chain-deficient (FcRgamma(-/-)) mice. HeFi-1, given at a dose of 100 microg weekly for 4 weeks, significantly prolonged survival of the ALCL-bearing SCID/NOD wild-type and SCID/NOD FcRgamma(-/-) mice (P < .01) as compared with the control groups. In vitro studies showed that HeFi-1 inhibited the proliferation of karpas299 cells, whereas daclizumab did not inhibit cell proliferation. We demonstrated that the expression of FcRgamma on polymorphonuclear leukocytes and monocytes was not required for HeFi-1-mediated tumor growth inhibition in vivo, although it was required for daclizumab.
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PMID:Effective therapy for a murine model of human anaplastic large-cell lymphoma with the anti-CD30 monoclonal antibody, HeFi-1, does not require activating Fc receptors. 1655 68

GPVI is a 62-kDa membrane glycoprotein expressed in noncovalent association with the Fc receptor gamma chain on human and murine platelets and serves as the major activating receptor for collagen. GPVI-specific antibodies have the capacity to specifically deplete GPVI from mouse and human platelets in vivo, rendering them unresponsive to collagen and GPVI-specific agonists. Such antibodies do not remove GPVI from noncirculating platelets in vitro, however, making it difficult to evaluate their antithrombotic potential and mechanism of action, particularly in human platelets. We devised a model system in which human platelets are introduced into the retroorbital plexus of nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice, allowed to circulate, and evaluated for the effects of GPVI-specific murine monoclonal antibodies (mAbs) on platelet survival and function. GPVI-specific mAbs triggered depletion of GPVI from human, but not murine, platelets. Soluble truncated human GPVI appeared concomitantly in mouse plasma. GPVI-depleted human platelets had markedly diminished responses to GPVI-specific agonists and unexpectedly exhibited somewhat depressed responses to G-protein-coupled agonists. The ability to evaluate in living mice the in vivo function and survival of circulating human platelets may prove valuable for determining mechanisms of antibody-mediated platelet passivation and aid in the development of novel anti-platelet therapeutics.
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PMID:Activation-independent, antibody-mediated removal of GPVI from circulating human platelets: development of a novel NOD/SCID mouse model to evaluate the in vivo effectiveness of anti-human platelet agents. 1656 73

Severe combined immunodeficiency (SCID) represents a genetically heterogeneous group of primary immunodeficiency disorders. Irrespective of the genetic defect, patients with SCID may be engrafted with transplacentally derived maternal T-lymphocytes that in a subset of cases may be responsive to phytohemagglutinin. Here, we present, from a genetic perspective, an SCID patient who not only harbored a novel mutation in the gene encoding the common gamma chain (gamma c) of the IL-2 receptor (IL2RG), but also carried reactive maternal T lymphocytes that produced a karyotype that was initially perplexing.
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PMID:A novel IL2RG mutation associated with maternal T lymphocyte engraftment in a patient with severe combined immunodeficiency. 1660 12

This review comments on basic and clinical immunology articles that were published in 2005, with a focus on those that appeared in the Journal of Allergy and Clinical Immunology. In the area of basic immunology, mechanisms of the innate immune system and its interaction with the adaptive immune system were described, with special consideration to applications in biodefense strategies. T regulatory cells were further characterized in their role for the control of allergic, autoimmune, and neoplastic disorders. The function of the thymus Hassall's corpuscles was reported to be the generation of T regulatory cells. Flavonoid molecules obtained from medicinal herbs, including astilbin and epigallocatechin gallate, were discovered to have immunomodulatory properties. Advances in clinical immunology resulted from efforts to develop a newborn screening test for severe combined immunodeficiency and the elucidation of the crystal structure of the IL-2 receptor gamma chain. Mutations in the membrane receptor transmembrane activator and calcium modulator and cyclophilin ligand interactor were found in patients with common variable immunodeficiency. New therapeutic options are described, such as the use of infliximab for granulomas and GM-CSF for chronic ulcers in patients with common variable immunodeficiency. The importance of mucosal immunity in acute HIV infection is cited, as is the role of CD8+ T-cell activation in HIV disease progression in children.
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PMID:Advances in basic and clinical immunology. 1689 Jul 76


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