[Interactions between nuclear polyhedrosis viruses and vertebrate cells (author's transl)].

The influence of NPV on mammals was tested in animals and tissue cultures. Toxicity experiments were performed in rats: per os application (3 X 10(9) Virusinclusionbodies per kg body weight) and intravenous (5 X 10(8) Virusinclusionbodies per kg body weight). Skin irrition was performed in guinea pigs. In each tested animal no virus induced changes could be shown. Tissue culture studies were done in tissues of human (Hela Ohio), monkey (Vero) and rats (REC). The infectious unit was Ac NPV derived from infected, virus-producing insect tissue cultures. Three blind passages were done in each examined cell type and no signs of viral replication could be shown. An additional infectivity assay of cellfree extracts in insect cell cultures as indicator system remained negative.