- Volume 16, Issue 3, 1972

Studies on the interaction with cells of the double-stranded complex of polyriboinosinic acid and polyribocytidylic acid [poly(rI).poly(rC)] have shown that the polymer binds rapidly to the cell and that of this only a very small amount penetrates into the cell (Bausek & Merigan, 1969). It has been shown further that the interferon inducing capacity of synthetic polynucleotides is markedly enhanced upon pre-incubation of the polymers at 37° in tissue culture medium in the absence of polycations (De Clercq, Wells & Merigan, 1970; De Clercq & Merigan, 1971) and that the preheated polymers bind more rapidly to the cell and persist for a longer time at the outer cell membrane than do the unheated polymers (De Clercq et al. 1971). Although these studies do not indicate whether the interferon response is triggered by the bulk of cell-associated polymer that resides at the cell surface or by the minute amount that penetrates into the cell (Bausek & Merigan, 1969; De Clercq et al. 1971), they suggest that the cell surface may play an important role in the production of interferon by synthetic polynucleotides.