[How the immune system protects us against disease].
D001402:B-Lymphocytes / Q000502:physiology*; D006801:Humans; D007107:Immune System / Q000502:physiology*; D007111:Immunity, Cellular / Q000502:physiology; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D013601:T-Lymphocytes / Q000502:physiology*