Induction of Proteins in Human Lymphoblastoid Cells by Recombinant Alpha Interferon

Two-dimensional gel electrophoresis, using either silver staining or pulse labeling with ³⁵S-L-methionine and autoradiography, was employed to determine changes in the synthesis of proteins that may be involved in the antiproliferative effects of recombinant alpha interferon (IFNrA) on Burkitt's lymphoma Daudi cells. IFNrA initiated and/or augmented the synthesis of at least 13 proteins that were distinct in molecular weights and isoelectric properties. Synthesis of several of these IFN-enhanced proteins was inhibited by actinomycin-D, an inhibitor of mRNA synthesis. Although IFN-induced antiproliferative effects were observed at 48 h, an increase in the synthesis of several proteins was observed as early as 3 h. The levels of these IFN-enhanced proteins in treated cells continued to increase through 24 h. At least two proteins of approximately 17 kD were observed to be synthesized in IFN-treated cells but not in control cells. Neither inhibition of synthesis of any particular prolein nor post-synthetic modification of proteins in response to IFNrA was observed with these methods. The results of this study are compared and contrasted to those of several other laboratories.