ANTIENDOMETRIAL LYMPHOCYTOTOXICITY AND NATURAL-KILLER-CELL ACTIVITY IN BABOONS (PAPIO-ANUBIS AND PAPIO-CYNOCEPHALUS) WITH ENDOMETRIOSIS

This study was performed to test the hypothesis that antiendometrial, lymphocyte-mediated cytotoxicity and natural killer (NK) activity are reduced in baboons with endometriosis when compared to animals with a normal pelvis, Lymphocyte-mediated cytotoxicity was determined in 28 b aboons (15 with endometriosis, 13 with normal pelvis) and NK cell acti vity was evaluated in 42 baboons (31 with endometriosis, 11 with norma l pelvis), Anti-endometrial lymphocyte-mediated cytotoxicity was deter mined by a 20 h assay with effector-target ratios of 50:1 and 25:1. Th e NK activity (K562 cell line as target) was simultaneously measured i n all animals during a 4 h assay with effector:target ratios of 200:1, 100:1, 50:1, 25:1, 12:1, 6:1 and 3:1, Statistical analysis was perfor med using analysis of variance, paired rank, Mann-Whitney, Kruskal-Wal lis and Fisher exact tests where appropriate, Lymphocyte-mediated cyto toxicity was significantly lower (P < 0.025) in baboons with endometri osis (mean 5.9 +/- 8.7%, median 0%, range 0-26%) than in animals with a normal pelvis (mean 22.9 +/- 23.0%, median 7%, range 0-78%), This di fference could be explained by the absence of cytotoxicity in baboons with moderate to severe endometriosis, probably due to high spontaneou s release of Cr-51 from labelled target cells. When stricter criteria were used and only animals with a labelling index (maximal/spontaneous release) of greater than or equal to 1.7 were analysed (n = 11), the anti-endometrial cytotoxicity was comparable between baboons with and without endometriosis. NK cell activity was also comparable in primate s with and without endometriosis. In conclusion, no difference in lymp hocyte-mediated cytotoxicity and NK cell activity was observed between baboons with and without endometriosis.