Publication Date:
1993-02-12
Description:
The ligand for CD40 (CD40L) is a membrane glycoprotein on activated T cells that induces B cell proliferation and immunoglobulin secretion. Abnormalities in the CD40L gene were associated with an X-linked immunodeficiency in humans [hyper-IgM (immunoglobulin M) syndrome]. This disease is characterized by elevated concentrations of serum IgM and decreased amounts of all other isotypes. CD40L complementary DNAs from three of four patients with this syndrome contained distinct point mutations. Recombinant expression of two of the mutant CD40L complementary DNAs resulted in proteins incapable of binding to CD40 and unable to induce proliferation or IgE secretion from normal B cells. Activated T cells from the four affected patients failed to express wild-type CD40L, although their B cells responded normally to wild-type CD40L. Thus, these CD40L defects lead to a T cell abnormality that results in the failure of patient B cells to undergo immunoglobulin class switching.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Allen, R C -- Armitage, R J -- Conley, M E -- Rosenblatt, H -- Jenkins, N A -- Copeland, N G -- Bedell, M A -- Edelhoff, S -- Disteche, C M -- Simoneaux, D K -- A125129/PHS HHS/ -- N01-CO-74101/CO/NCI NIH HHS/ -- New York, N.Y. -- Science. 1993 Feb 12;259(5097):990-3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7679801" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Antigens, CD/*metabolism
;
Antigens, CD40
;
Antigens, Differentiation, B-Lymphocyte/*metabolism
;
Base Sequence
;
CD40 Ligand
;
DNA/chemistry/genetics
;
Humans
;
Immunoglobulin M/*blood
;
Immunologic Deficiency Syndromes/*genetics/immunology
;
Ligands
;
Male
;
Membrane Glycoproteins/*genetics
;
Mice
;
Molecular Sequence Data
;
*Point Mutation
;
Polymerase Chain Reaction
;
T-Lymphocytes/*immunology
;
Transfection
;
*X Chromosome
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
