The numbers of perforin-, granzyme B- and TIA-1-positive cells in liver biopsies after liver transplantation. The numbers of perforin- and granzyme B-positive cells in the portal tract area in the ACR group were greater than in the non-ACR groups (A, B), while in lobules there were more positive cells in the ACR group than in the BC, OI and UD groups, but a similar amount to that in the I/R group (D, E). There were significantly more TIA-1-positive cells in the portal tract area in the ACR group than in the non-ACR groups (C), but in lobules there were significantly fewer in the ACR group than in the BC, I/R or OI groups (F). ACR, acute cellular rejection; BC, biliary complications; I/R, ischemic/reperfusion injury; OI, opportunistic infection; UD, undefined complications. *P<0.01, #P<0.05, compared with ACR.