CONSTITUTIVE INTERFERON EXPRESSION FROM RETROVIRAL VECTOR

A genomic fragment with the human P-interferon gene was cloned into a pL3-4, a defective Moloney murine leukemia virus (M-MuLV) vector. Here we show that clones selected after viral infection of mouse NIH 3T3 c ells constitutively produced 128 IU/ml of human beta-interferon. Const itutive synthesis of retroviral RNA was confirmed by dot blot hybridiz ation of RNA isolated from two of the selected clones. Poly(I).poly(C) and cycloheximide induction resulted in an increased RNA level, but t his was not reflected in an increased production of biologically activ e interferon.