Thymus dependence of rabies vaccine.

Immune responses to rabies vaccine were compared with those to known thymus-dependent and thymus-independent antigens, in nude mice and their normal litter mates. No antibody response to, or protection against, challenge was observed in nude mice inoculated with either 1 or 2 doses of rabies vaccine. A single dose of the same vaccine induced a substantial antibody response and protected normal mice. These data indicate that the antigens in rabies vaccine that induce neutralizing antibody and protect mice are thymus-dependent.