Interferon production in athymic nude mice.

Athymic (homozygous nude) mice of a non-inbred stock had relatively little antiviral activity in their serum compared with normal control mice at 4, 6 and 6.5 h after the intraperitoneal injection of Newcastle disease virus. The antiviral activity in the serum had the characteristics of interferon. At 10 h after injection and thereafter, the serum titres were comparable in nude and normal control mice. Exceptional nude mice with thymus-like tissue sometimes produced interferon more or less normally. Transfer of spleen cells from normal donor mice, but not from nude donors, led to increased serum interferon levels in nude recipient mice at 4 h after virus injection.