Autogenous and virus-induced interferons from lines of lymphoblastoid cells.

Lymphoblastoid cell lines derived from Burkitt's lymphoma or leukocytes of leukemic or healthy donors were examined for their ability to produce autogenous and virus-induced intefferons. All interferon yields were maximal when 107 cells/ ml were incubated for 24 hr on a rotary shaker at 37~ Of 10 viruses tested only Newcastle disease virus (NDV) and reovirus type 3 were found to be effective inducers of interferon. The cell lines differed with respect to (a) the yields of autogenous interferon (0 to >32 units/ml); (b) the yields of virus-induced interferon (8-1024 units/ml); and (c) the minimal input multiplicities of active or UV-inactivated NDV (1-50) required to induce detectable interferon synthesis. Maximal yields of interferon were obtained in all instances with NDV or NDVuv at an input multiplicity of 50. Autogenous and virus-induced interferons could not be differentiated by various chemical or physical procedures. By means of gel Fdtration, using Sephadex G-100, the molecular weights were estimated to be about 26,000 for 2 autogenous and 2 virus-induced interferons. While cultures yielding autogenous interferons may nevertheless be highly susceptible to vesicular stomatitis virus (VSV), they could be protected by addition of concentrated autogenous interferon derived from autochthonous cells. The protection was, however, less enduring than that conferred with virus-induced interferon. Results obtained with 16 cloned lines of Ogun cells suggested that all cells of this line produce small amounts of autogenous interferon rather than that a few cells synthesize large quantities. Kinetic studies revealed that the presence of a critical amount of autogenous interferon enhanced the speed of virus-induced interferon synthesis. Peak titers were obtained within 6 8 hr under these conditions, whereas a lag phase of >8 hr was