In previously reported experiments (1) we have shown that the absorption of antigen from the cutaneous tissues of specifically immunized animals proceeds at a rate markedly in excess of that occurring in normal animals. Horse serum, injected intracutaneously into guinea-pigs immunized against horse serum, disappeared from the site of injection much earlier than did horse serum similarly injected into normal pigs. The question was not determined, however, as to whether the heightened reactivity of the tissues, attendant upon the immune state, pertained to the specific antigen only or whether it indicated an activation of a general mechanism of elimination extending to non-specific antigens. The experiments here reported deal with this point.
In the present work guinea-pigs immunized to one antigen were tested by the intracutaneous injection of the specific and also of a heterologous antigen to demonstrate to what extent absorption depends upon a specific factor.