title: Age-related decrease in frequencies of B-cell precursors and specific helper T cells involved in the IgG anti-tetanus toxoid antibody production in humans.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D000921:Antibody-Producing Cells / Q000166:cytology / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology* / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D007117:Immunization, Secondary; D007074:Immunoglobulin G / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000528:radiation effects; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000528:radiation effects; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000528:radiation effects; D013745:Tetanus Toxoid / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D007074:Immunoglobulin G; D013745:Tetanus Toxoid