Interferon Production by Normal Mouse Tissues in Organ Cultures

Abstract

Freshly removed tissues of normal untreated mice produced relatively high amounts of interferon (IFN) in organ cultures. Lymph nodes, subcutaneous tissue, and the capsule of the kidney were the most active IFN producers. The abdominal wall and the thigh muscle were less active, whereas the lungs and spleen, similarly to the peritoneal exudate and bone marrow cells, produced only threshold amounts of IFN. Liver cultures did not produce IFN under these experimental conditions. Cultures prepared from IFN-pretreated animals produced three- to fourfold more IFN. Homogenates of tissue prepared immediately after their removal did not contain a detectable amount of IFN. The bulk of the IFN activity was produced during the first 6 h of incubation at 37 degrees C. Omission of serum from the culture medium, and the presence of 50 micrograms/ml of polymyxin B, did not inhibit IFN production. Cultures incubated at 0 degrees did not release any IFN. The IFN activity produced by all types of tissue was pH 2 resistant and it was neutralized by an antiserum to murine (Mu) IFN-beta. Different strains of mice produced comparable amounts of IFN under the present experimental conditions.