Depressed natural and lectin-dependent cell-mediated cytotoxicity against adherent HEp-2 cells in patients with systemic lupus erythematosus.

Natural cell-mediated cytotoxicity /NCMC/ was evaluated using human adherent 3H-thymidine-prelabelled HEp-2 epipharynx carcinoma cells as targets at 50:1 effector-target cell ratio in a 24 hr assay. For lectin-dependent cell-mediated cytotoxicity /LDCC/ studies cultures contained also 25/micrograms/ml concanavalin A /Con A/. Peripheral blood mononuclear cells /PBMC/ of nine patients with active systemic lupus erythematosus /SLE/ failed to exert NCMC or LDCC against HEp-2 targets. In contrast, an increased adherence /decreased detachment from the monolayer/ of HEp-2 target cells was observed in the presence of PBMC from SLE patients that was further promoted by the addition of Con A during LDCC assay.