Kinetics of multinucleate giant cell formation and their modification by various agents in foreign body reactions.

Foreign body multinucleate giant cells were produced by the implantation of a strip of Melenex in the subcutaneous tissues of mice. The implants were removed at various intervals, and the proportion of multinucleate giant cells as well as the number of nuclei they contained were counted and statistically assessed. The greatest proportion of giant cells was reached 4 weeks after implantation, when 25% of the attached cells were multinucleated. The mean nuclear content however was greatest approximately 2 weeks after implantation and rapidly fell over the ensuing weeks. The fusion potential however, remained almost unaltered for the remainder of the experimental period. Transplantation of 7-day Melenex implants from normal donors into lethally irradiated recipients demonstrated that the halflife of the giant cells is only a few days. Treatment with carrageenin, species-specific antisera, actinomycin D and cortisone inhibited, while puromycin enhanced, multinucleate cell formation. Calcium gluconate, EDTA and irradiation had no significant effect. The possible interpretation of some of these findings is discussed.