- poly(G)'poly(C) (polyguacil) - is a slightly toxic interferon inductor and a promising anti-viral agent for humans and animals (2, 3, 5, 8, ii). Polynucleotide complexes have several biological properties: they stimulate immunity and have antitumorigenic and radioprotecting action (2). In the present work, we studied the ability of polyguacil to stimulate adaptation to