[Hyper- and hypo-reactivity in mice with regard to the induction of virus inhibitory factor or interferon].

1. IF induction in mice with Newcastle disease virus produced hyperreactivity on subsequent induction with certain doses of poly I:C. 2. Laparotomy or intraperitoneal injection with air caused temporary hyporeactivity of spleen and lungs on IF induction with endotoxin. Laparotomy in splenectomised mice did not affect IF formation in lungs.