Formalin stress reaction of germfree and conventional mice treated with Bordetella pertussis vaccine.

Germfree and conventional mice responded similarly to pertussis vaccine treatment. In both groups, lymphocytosis and splenomegaly developed in a similar proportion. The formalin stress reaction of germfree and conventional mice with hypertrophic lymphoid organs induced by pertussis vaccine differed from that of untreated mice: the treated germfree and conventional mice showed a acute increase of lymphocytosis without an significant change in splenomegaly.