Isogeneic versus allogeneic antiserum in the prophylaxis of experimental rabies.

With a view to establishing whether rabies antiserum derived from a species genetically identical to a challenged recipient would increase or decrease its effectiveness compared with that of allogeneic antiserum, rabies immune sera produced in an inbred strain of mice and in donkeys were tested, either alone or with a course of vaccine inoculations, in mice of the same strain a few hours after intramuscular challenge with fixed CVS rabies virus. Surviving mice were bled at intervals over a year and the rabies antibodies assayed in pooled sera.There was no evidence that the isogeneic antiserum was either more or less effective than the allogeneic, nor was there a difference between the two in the decay of passive antibody; similarly, there was no marked difference in their ability to interfere with the active production of antibody resulting from the highly potent vaccine used.