title: A defect in antigen-specific antibody production due to a lack of T helper cells in a patient with ataxia-telangiectasia.
mesh_terms: D000917:Antibody Formation; D001260:Ataxia Telangiectasia / Q000276:immunology*; D000939:Epitopes; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000939:Epitopes; D007136:Immunoglobulins