title: Defective expression of T cell-associated glycoprotein in severe combined immunodeficiency.
abstract: A T cell surface membrane-associated glycoprotein, Tp40 (40,000 mol wt), also designated as CD-7, was not expressed by the T cells of a patient with severe combined immunodeficiency. In addition to this abnormality, T cell proliferative responses to mitogens were defective and the IL-2 receptor expression was deficient on the patient's T lymphocytes. However, his T cells were found to provide help for the differentiation of normal B cells to Ig-secreting cells. Abundant circulating B cells were detected. These B cells proliferated normally in the presence of anti-mu antibodies and B cell growth factors, but did not differentiate into antibody-secreting cells when provided with the help of normal T cells. In addition, his activated B cells did not proliferate to IL-2 even though IL-2 receptors were expressed. A successful allogeneic histocompatible bone marrow transplantation resulting in T cell engraftment corrected both the T and B cell immunodeficiencies. These findings support the hypothesis that the Tp40 deficiency present in this patient is related to a defect of the T cell precursors, and that Tp40 plays important roles not only essential to T cell interactions but also to certain aspects of T-B cell interaction during the early lymphoid development.
authors.forename: L K
authors.initials: LK
authors.lastname: Jung
authors.forename: S M
authors.initials: SM
authors.lastname: Fu
authors.forename: T
authors.initials: T
authors.lastname: Hara
authors.forename: N
authors.initials: N
authors.lastname: Kapoor
authors.forename: R A
authors.initials: RA
authors.lastname: Good
mesh_terms: D000911:Antibodies, Monoclonal; D000917:Antibody Formation; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology; D016026:Bone Marrow Transplantation; D002454:Cell Differentiation; D002675:Child, Preschool; D006023:Glycoproteins / Q000276:immunology / Q000378:metabolism; D006133:Growth Substances / Q000494:pharmacology; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000276:immunology / Q000378:metabolism*; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4; D008213:Lymphocyte Activation; D008222:Lymphokines / Q000494:pharmacology; D008297:Male; D008565:Membrane Proteins / Q000276:immunology / Q000378:metabolism; D008970:Molecular Weight; D011971:Receptors, Immunologic / Q000378:metabolism; D015375:Receptors, Interleukin-2; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D006023:Glycoproteins; D006133:Growth Substances; D007376:Interleukin-2; D008222:Lymphokines; D008565:Membrane Proteins; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D015847:Interleukin-4