Impairment of K cell activity by inoculation of bovine leukemia cell line (FLK) in nude mice.

Abstract

In athymic nude mice previously inoculated with bovine leukemia cell line (fetal lamb kidney; FLK) the clearance of the same cells was markedly delayed. To know the mechanisms of impairment of clearance rate, we examined natural killer (NK) and killer (K) cell activities of spleen cells against FLK cells by 8 hr-51Cr release assay. Splenic K cell activity against FLK cells markedly decreased in nude mice treated previously with viable FLK cells when compared to the activity of spleen cells from untreated nude mice. However, there were no significant differences in NK cell activity against FLK cells and YAC-1 cells between the two groups of mice. Treatment of nude mice with glutaraldehyde-fixed and killed FLK cells had no influence on both NK and K cell activities. These results suggest that inoculation of viable FLK cells impairs K cell activity of nude mice and therefore the elimination of FLK cells from the body was delayed. The impairment of K cell activity may result in progress of tumors in nude mice.