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)

The human T cell receptor was studied using an anchored-polymerase chain reaction (A-PCR) and hybridization with V beta-specific oligonucleotide probes, together with the few anti-V beta monoclonal antibodies (mAb) available. After confirming the semiquantitative and reproducible nature of the A-PCR technique, we assessed the complete V beta repertoire in sorted CD4+ and CD8+ lymphocyte populations from three normal donors. These experiments confirmed the absence of V beta-restricted deletions in human peripheral cells, in contrast to several mouse strains. This feature makes it difficult to study negative selection in man, given the apparent absence of an endogenous superantigen corresponding to the Mls system in the mouse. To investigate human V beta repertoire shaping, we studied V beta usage in CD4+ and CD8+ T cells from children with an inherited immunodeficiency characterized by defective expression of human leukocyte antigen class II molecules. An initial study using anti-V beta monoclonal antibodies failed to show significant abnormalities in V beta usage. Four patients analyzed using the A-PCR method all had a polyclonal V beta repertoire, suggesting normal positive selection and raising questions as to the importance of V beta major histocompatibility complex (MHC) interactions and the role of thymic MHC density in shaping the V beta repertoire.
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PMID:Normal T cell receptor V beta usage in a primary immunodeficiency associated with HLA class II deficiency. 809 85

Major histocompatibility complex class II deficiency (bare lymphocyte syndrome) is a rare primary immunodeficiency disorder characterized by profound defects in human leukocyte antigen class II expression, inconsistent and incomplete expression of human leukocyte antigen class I molecules, and a complete lack of cellular and humoral immune responses to foreign antigens. To define the clinical and immunologic characteristics, outcome, and natural history of major histocompatibility complex class II deficiency, we retrospectively analyzed 30 consecutive patients. Clinical onset occurred in the first year of life, usually involving recurrent bronchopulmonary infections and chronic diarrhea. The clinical course was complicated by viral meningoencephalitis, hepatitis, cholangitis, and various autoimmune phenomena. Prognosis was very poor: the mean age at the time of death was 4 years. The main cause of death was overwhelming viral infection. Recent advances in bone marrow transplantation have raised hopes of curative treatment: 6 of 14 patients who underwent bone marrow transplantation were cured. Long-term survival after human leukocyte antigen-identical and haploidentical bone marrow transplantation seemed to depend primarily on the presence of preexisting viral infections.
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PMID:Major histocompatibility complex class II deficiency: clinical manifestations, immunologic features, and outcome. 822 25

Major histocompatibility complex (MHC) class II deficiency is a rare primary immunodeficiency disorder characterized by defects in human leukocyte antigen class II expression, inconsistent expression of human leukocyte class I molecules, and a lack of cellular and humoral immune responses to foreign antigens. Clinical onset occurs early in life with recurrent infections and chronic diarrhea. The prognosis is poor, and mean age at the time of death is 4 years. The only curative treatment is bone marrow transplantation (BMT), which allows the immune system's reconstitution. BMT should be done early in life, because long-term survival seems to depend on the number of previous viral infections. We report the case of an MHC class II deficiency discovered late in a 4-year-old girl by means of immunohistochemistry of small bowel biopsy revealing the absence of MHC class II expression. The child received a BMT twice but died because of a overwhelming viral infection. This case underlines the necessity to explore children presenting with infections and chronic diarrhea in order to find MHC class II deficiency. Usually, diagnosis is performed on cytospins, but when it has been missed clinically, it can be performed by using immunohistochemistry on small bowel biopsies.
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PMID:Major histocompatibility complex class II deficiency needs an early diagnosis: report of a case. 921 59