Depressed lectin-dependent cell-mediated cytotoxicity against HEp-2 cells in patients with metastasizing solid tumour

Lectin-dependent cell-mediated cytotoxicity (LDCC) of peripheral blood mononuclear cells (PBMC) from tumour patients was evaluated using human adherent 3H-TdR-prelabelled HEp-2 epipharynx carcinoma cells as targets at 50:1 effector-target cell ratio with 25 micrograms/ml concanavalin A (Con A) in a 24h assay. PBMC of nine patients with metastasizing solid tumour failed to exert cytotoxicity against HEp-2 targets. In contrast, increased survival (decreased detachment from the monolayer) of HEp-2 cells was observed in the presence of PBMC from tumour patients that was significantly enhanced by addition of Con A during LDCC assay.