Thymus dependence of the antibody response to tetanus toxoid in mice

Both the IgM and IgG antibody responses to tetanus toxoid were greatly reduced in adult thymectomized, irradiated, foetal liver reconstituted mice, in contrast with results published for neonatally thymectomized mice. This evidence lends further support to the notion that all IgG responses to protein antigens are thymus dependent.