RT Journal Article SR Electronic(1) A1 Stewart, W. E. A1 LeGoff, Sylvia A1 Wiranowska-Stewart, MarzennaYR 1977 T1 Characterization of Two Distinct Molecular Populations of Type I Mouse Interferons JF Journal of General Virology, VO 37 IS 2 SP 277 OP 284 DO https://doi.org/10.1099/0022-1317-37-2-277 PB Microbiology Society, SN 1465-2099, AB Summary The molecular heterogeneity of acid-stable (Type I) mouse interferons induced in C243 cells by Newcastle disease virus was analysed by SDS-polyacrylamide gel electrophoresis under non-reducing and reducing conditions, and the profiles of antiviral activities obtained were characterized biologically in mouse cells and in heterologous (guinea-pig) cells. Two bands of activity, A and B, were consistently present in all interferon preparations tested: under reducing conditions, the activity in all fractions of band A (with a peak of activity at about 38000 daltons) was uniformly increased, while that of band B (with a peak at about 22000 daltons) was uniformly diminished. All the active fraction in band A had only slight activity (less than 10% of homologous titres) on guinea-pig cells, whereas all those in band B were significantly more active on guinea-pig cells than on homologous L cells. Thus, mouse type I interferon preparations contain two molecular populations of interferons that can be distinguished physically (by size), biochemically (by the effect of reduction on reactivation from SDS) and biologically (by activity in heterologous cells)., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-37-2-277