Relationship between susceptibility to apoptosis and Fas expression in peripheral blood T cells from uremic patients: a possible mechanism for lymphopenia in chronic renal failure.

Chronic renal failure (CRF) is often complicated by lymphopenia, which may be partly responsible for immune deficiency. We hypothesized that lymphopenia in CRF might result from apoptosis of T cells in vivo. To elucidate the involvement of Fas antigen which mediates apoptosis, we analyzed Fas expression on peripheral blood T cells in uremic non-dialyzed (non-HD) patients and hemodialysis (HD) patients. T cells from both uremic groups expressed Fas with higher intensity than control T cells. When two uremic groups were compared, Fas intensity on T cells was significantly higher in non-HD patients than in patients on HD. Moreover, uremic T cells were shown to undergo accelerated apoptosis when cultured in vitro, in correlation with Fas expression. Our results suggest that T cells in CRF may undergo apoptosis by the Fas system and that hemodialysis treatment has beneficial effects in the light of the inhibition of T cell apoptosis.