Fig. 2.

Non-Fas-mediated killing of P815 and K562 target cells by peripheral blood mononuclear cells (PBMC) from woodchucks with newly acquired and chronic woodchuck hepatitis virus (WHV) infections and from healthy controls. PBMC from WHV-negative, healthy animals (10 individual PBMC samples; □) and from woodchucks with recently induced WHV infection (14 PBMC samples; hatched bars) or advanced chronic WHV hepatitis (11 PBMC samples; ▪) were incubated with ⁵¹Cr-labelled P815 or K562 cells. (a) Fas-positive P815 cells were used intact (untreated), preincubated with anti-Fas Jo2 MoAb or tested in the presence of the protein synthesis inhibitor cyclohexamide (CHX). (b) The Fas-negative K562 cells were used intact (untreated) or tested in the presence of the perforin release inhibitor colchicine. Results are presented at an E:T ratio of 50:1 from five separate experiments and are expressed as a mean percentage of the specific lysis of P815 or K562 cells ± s.e.m.