title: Phenotypic and functional T cell subset abnormalities in patients with aplastic anaemia and hypogammaglobulinaemia.
abstract: We have investigated T cell abnormalities present in blood of two patients with aplastic anaemia and hypogammaglobulinaemia. There was a marked increase in class II, major histocompatibility complex, HLA-DR+ antigen, and interleukin-2 receptor (Tac+) bearing CD4+ helper/inducer T cells, and a concurrent reduction of CD8+ suppressor/cytotoxic T cells. These CD4+ T cells produced an elevated proliferative response to phytohaemagglutinin and concanavalin A. Interestingly, the T cell subset mainly responsible for elevated production of the lymphokine, interleukin-2, under the stimulus of phytohaemagglutinin, was characterized as belonging to a CD4+ T cell subset. Functional studies, using a pokeweed mitogen driven IgG, IgA and IgM synthesis, demonstrated a correlation between CD4+ T cell deficient helper function for B cell differentiation and the clinical finding of the patient's hypogammaglobulinaemia.
authors.affiliation: Department of Immunology, King Saud University, College of Medicine, Abha, Saudi Arabia.
authors.forename: S
authors.initials: S
authors.lastname: Raziuddin
authors.forename: A K
authors.initials: AK
authors.lastname: Sheikha
mesh_terms: D000328:Adult; D000361:Agammaglobulinemia / Q000276:immunology*; D000741:Anemia, Aplastic / Q000276:immunology*; D002455:Cell Division; D005260:Female; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis; D007376:Interleukin-2 / Q000096:biosynthesis; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology* / Q000473:pathology
chemical_list: D007136:Immunoglobulins; D007376:Interleukin-2