Relationship between Cell-Interaction and Antiviral Activity of Polyriboinosinic Acid-Polyribocytidylic Acid in Different Cell Cultures

SUMMARY Interaction of [3H]-labelled poly(rI).poly(rC) with the cell has been studied in several cell cultures which differ markedly in their sensitivity to the antiviral activity of the polynucleotide (in order of decreasing sensitivity): primary rabbit kidney (PRK) cells, human skin fibroblasts (HSF), mouse embryo fibroblasts (MEF), mouse L-929 cells, rabbit kidney (RK 13) cells, HeLa, BSC-1 and VERO cells. No significant differences were noted in the amounts of either total or acid-insoluble radioactivity associated with the cell at various times, following exposure of [3H]-poly(rI).poly(rC) to these different cell cultures. No significant differences were noted in the fate of cell-bound [3H]-poly(rI).poly(rC) in four out of the eight cell cultures tested. However, significant differences were observed in the sensitivity of cell-bound [3H]-poly(rI).poly(rC) to extraneous ribonuclease treatment: [3H]-poly(rI).poly(rC) bound to the cells that are most sensitive to the antiviral activity of the polynucleotide (PRK, HSF, MEF, L-929, RK 13) appeared to be markedly more accessible to ribonuclease treatment than [3H]-poly(rI).poly(rC) bound to cells that are rather insensitive to the antiviral activity of the polynucleotide (HeLa, BSC-1, VERO).