title: The T-, B-cell paradigm dilemma as highlighted by a view of the evolution of immunity.
mesh_terms: D000818:Animals; D001001:Anura; D001402:B-Lymphocytes / Q000276:immunology*; D005075:Biological Evolution; D000939:Epitopes; D007109:Immunity; D007075:Immunoglobulin M; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology; D014714:Vertebrates
chemical_list: D000939:Epitopes; D007075:Immunoglobulin M