Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The X-linked form of hyper-IgM syndrome (HIGM1) is a rare disorder characterized by the inability of B cells to undergo isotype switch by a deficiency of CD40 ligand (CD40L) on activated T lymphocytes. The patients suffer from recurrent infections not only due to a lack of B lymphocyte activation but also due to defect of T lymphocyte functions. In addition, neutropenia is frequently accompanied by these symptoms. A patient with HIGM1, we experienced, suffered from recurrent infections and neutropenia. But he had a normal number of hematopoietic stem cell by the in vitro colony forming assay. CD34+ myeloid stem cell has been known to express CD40. We speculated by these facts that myeloid cell numbers are regulated by CD40-CD40L interaction.
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PMID:[Neutropenia in patient with X-linked hyper-IgM syndrome]. 853 35

A male child presented with recurrent respiratory infections, otitis media, and oral ulceration and was found to be neutropenic. Investigations showed hypogammaglobulinaemia with normal serum IgM and a novel deletion in the gene for CD40 ligand on his X chromosome. Intravenous gammaglobulin did not lead to resolution of his neutropenia; G-CSF was also necessary.
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PMID:CD40 ligand deficiency presenting as unresponsive neutropenia. 866 67

Human CD34+ multilineage progenitor cells (CD34HPC) from cord blood and bone marrow express CD40, a member of the tumor necrosis factor-receptor family present on various hematopoietic and nonhematopoietic cells. As hyper-IgM patients with mutated CD40 ligand (CD40L) exhibit neutropenia, no B cell memory, and altered T cell functions leading to severe infections, we investigated the potential role of CD40 on CD34HPC development. CD40-activated cord blood CD34HPC were found to proliferate and differentiate independently of granulocyte/macrophage colony-stimulating factor, into a cell population with prominent dendritic cell (DC) attributes including priming of allogeneic naive T cells. DC generated via the CD40 pathway displayed strong major histocompatibility complex class II DR but lacked detectable CD1a and CD40 expression. These features were shared by a dendritic population identified in situ in tonsillar T cell areas. Taken together, the present data demonstrate that CD40 is functional on CD34HPC and its cross-linking by CD40L+ cells results in the generation of DC that may prime immune reactions during antigen-driven responses to pathogenic invasion, thus providing a link between hematopoiesis, innate, and adaptive immunity.
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PMID:CD40 ligation on human cord blood CD34+ hematopoietic progenitors induces their proliferation and differentiation into functional dendritic cells. 901 82

We present a boy with hyper-IgM syndrome with a previously not reported mutation in the CD40 ligand gene. He also had a concomitant natural killer (NK) cell deficiency. He had no CD56+ or CD16+ cells and no NK activity as determined in 4 h chromium release cytotoxicity assay. After 5 days in culture with IL-2-containing medium, however, his peripheral blood mononuclear cells lysed both NK-sensitive and NK-resistant targets, showing that he had lymphokine-activated killer cell precursors in the circulation. Due to the associated neutropenia, he was treated with granulocyte colony-stimulating factor (G-CSF) and responded well. In the same period we observed a transient increase in the number of NK cells. Isolated NK cell deficiencies are extremely rare. We suggest that the defect in our patient is part of the hyper-IgM syndrome, probably representing the phenotype of the new mutation described. Thus, it is possible that both the neutropenia and the NK cell deficiency are due to lack of growth-promoting signals normally delivered by the CD40 ligand.
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PMID:A boy with X-linked hyper-IgM syndrome and natural killer cell deficiency. 903 Aug 57

We report the clinical and immunologic features and outcome in 56 patients with X-linked hyper-IgM syndrome, a disorder caused by mutations in the CD40 ligand gene. Upper and lower respiratory tract infections (the latter frequently caused by Pneumocystis carinii), chronic diarrhea, and liver involvement (both often associated with Cryptosporidium infection) were common. Many patients had chronic neutropenia associated with oral and rectal ulcers. The marked prevalence of infections caused by intracellular pathogens suggests some degree of impairment of cell-mediated immunity. Although lymphocyte counts and in vitro proliferation to mitogens were normal, a defective in vitro proliferative response to antigens was observed in some patients, and additional defects of cell-mediated immunity may be presumed on the basis of current knowledge of CD40-ligand function. All patients received regular infusions of immunoglobulins. Four patients underwent liver transplantation because of sclerosing cholangitis, which relapsed in there. Three patients underwent bone marrow transplantation. Thirteen patients (23%) died of infection and/or liver disease. X-linked hyper-IgM syndrome, once considered a clinical variant of hypogammaglobulinemia, is a severe immunodeficiency with significant cellular involvement and a high mortality rate.
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PMID:Clinical spectrum of X-linked hyper-IgM syndrome. 1093 36

X-linked hyperimmunoglobulin M (X-HIM) is a rare inherited immune deficiency disease that was first described in 1961. Affected patients suffer recurrent pyogenic and opportunistic infections, neutropenia, and an increased susceptibility to cancer. In 1993, five groups independently showed that this disease results from defects in the CD40 ligand gene. CD40 ligand is a 39-kDa protein expressed on the surface of activated CD4+ T cells that delivers contact-dependent signals to CD40-expressing cells: B cells, monocytes, dendritic cells, epithelial cells, endothelial cells, and fibroblasts. The loss of interaction between CD40 and its ligand results in an impairment of T-cell function, of B-cell differentiation, and of monocyte function. Identification of the genetic defect in X-HIM has provided a definitive diagnosis of the disease, a better description of the clinical manifestations, and the capacity for genetic screening. Studies of the role of CD40 and its ligand in the immune response from many laboratories around the world have provided a better understanding of the pathogenesis of the disease. Further research may lead to novel and definitive therapeutic options for patients with X-HIM.
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PMID:The X-linked hyperimmunoglobulin M syndrome. 980 Dec 61

X-linked hyper-IgM syndrome (XHIM) is a severe congenital immunodeficiency caused by mutations in CD154 (CD40 ligand, gp39), the T cell ligand for CD40 on B cells. Chronic or cyclic neutropenia is a frequent complicating feature that heightens susceptibility to severe infections. We describe a patient with a variant of XHIM who produced elevated levels of serum IgA as well as IgM and suffered from chronic severe neutropenia. Eight of ten leukocyte transfusions with cells from a maternal aunt, performed because of mucosal infections, resulted in similar episodes of endogenous granulocyte production. Transfection studies with the mutant CD154 protein indicate that the protein is expressed at the cell surface and forms an aberrant trimer that does not interact with CD40. The data suggest that allogeneic cells from the patient's aunt, probably activated T cells bearing functional CD154, may interact with CD40+ recipient cells to produce maturation of myeloid precursors in the bone marrow.
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PMID:Leukocyte transfusion-associated granulocyte responses in a patient with X-linked hyper-IgM syndrome. 985 88

X-linked hyper-IgM (X-HIM) syndrome is a primary immunodeficiency disease characterized by defects in both cellular and humoral immunity. X-HIM is caused by mutations in the gene for CD40 ligand (CD40L), a T cell membrane protein that mediates T cell-dependent immune functions. We report the case of a 6-year-old male with X-HIM due to an intronic mutation resulting in aberrant CD40L RNA splicing and absence of detectable CD40L protein. The patient had a history of multiple infectious complications and chronic neutropenia requiring treatment with recombinant granulocyte colony-stimulating factor, and underwent allogeneic bone marrow transplantation from an HLA-matched sibling donor. Following successful engraftment, T cell CD40L expression and immunoglobulin isotype switching were reconstituted and neutropenia resolved. Allogeneic bone marrow transplantation can correct neutropenia and reconstitute immune function in X-HIM.
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PMID:Correction of neutropenia and hypogammaglobulinemia in X-linked hyper-IgM syndrome by allogeneic bone marrow transplantation. 989 27

The optimal approach for stem cell transplantation in children with immunodeficiency has yet to be determined. Conditioning therapy is necessary for reliable engraftment and full immune reconstitution; however, the beneficial effect of cytoreductive conditioning is counterbalanced by increased short- and long-term treatment-related toxicity. Whether bone marrow transplantation with a nonmyeloablative preparative regimen was sufficient for the establishment of donor immune reconstitution, with the resultant correction of disease phenotype, was investigated. Eight patients with severe immunodeficiency states underwent T-cell replete bone marrow transplantation from a human leukocyte antigen-matched unrelated (n = 6) or sibling (n = 2) donor with nonmyeloablative conditioning using a fludarabine-melphalan-anti-lymphocyte globulin-based regimen. All patients had severe organ dysfunction that precluded transplantation with conventional conditioning. All patients were engrafted with predominantly donor hematopoiesis, and the duration of neutropenia was brief. Significant acute graft-versus-host disease (GVHD) did not develop, but one patient had limited chronic GVHD. One patient died of disease recurrence, and 3 have stable, mixed chimerism. At a median follow-up of 1 year, all patients have had good recovery of CD3(+) T-cell numbers, and 6 of 7 evaluable patients have normal phytohemagglutinin stimulation indices. The rate of immune reconstitution is comparable with that of historical controls undergoing standard myeloablative protocols. Two patients with CD40 ligand deficiency now show significant expression, and a patient with adenosine deaminase deficiency has improved deoxy adenosine triphosphate metabolites. In summary, it has been demonstrated that nonmyeloablative stem cell transplantation permits rapid engraftment from both sibling and unrelated donors with minimal toxicity even in the presence of severe organ dysfunction. If long-term immune reconstitution of patients treated with this protocol is demonstrated, it is believed this approach might offer significant advantages compared with standard protocols by combining adequate immune reconstitution with reduced short- and long-term toxicity. (Blood. 2000;96:1239-1246)
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PMID:Nonmyeloablative stem cell transplantation for congenital immunodeficiencies. 1094 63

Hyper-IgM immunodeficiency (HIM) is an immunological disorder characterized by normal or elevated serum IgM levels, and reduced serum IgG and IgA levels, due to the disruption of immunoglobulin class switching in B cells. X-linked hyper-IgM is caused by the defective expression of the CD40 ligand on activated T cells, which induces immunoglobulin class switching along with some cytokines, such as interleukin 4, by the signal transduction of CD40 in B cells. We report on a Japanese girl who initially showed low serum IgM, IgG and IgA levels like patients with common variable immunodeficiency; however, in the course of time, serum IgG levels became reduced and serum IgM levels increased, resulting in the typical immunoglobulin profile of HIM. Neutropenia, one of the features of X-linked HIM, was not observed. In spite of extremely low serum IgG levels, she did not show any predisposition to severe infection, even without gammaglobulin replacement therapy. No mutation of the CD40 ligand or CD40 was detected. Sequencing of the complementarity-determining region of immunoglobulin heavy-chain genes in peripheral B lymphocytes revealed that they were all in frame, and insertion of the N region was detected. These results indicate that the heavy-chain gene rearrangement in the patient's B cells is intact. Non-X-linked HIM has heterogeneous pathogenetic mechanisms, and some groups may show the resistance to infection at the healthy donor level. The underlying defects in non-X-linked HIM might be specifically involved in class switching.
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PMID:Long-term study of a female hyper-IgM immunodeficiency. 1109 55


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