Soluble interleukin-2 receptor and soluble CD8 in liver cirrhosis and obstructive jaundice

Abstract

Activated lymphocytes secrete soluble interleukin-2 receptor (sIL-2R); CD8-positive lymphocytes secrete soluble CD8 (sCD8). Liver dysfunction in cirrhosis and obstructive jaundice is known to result in depressed cellular immunity. To evaluate whether this is due to real inactivation of the immune system, we measured sIL-2R and sCD8 in the serum of 46 patients with liver cirrhosis, 25 patients with obstructive jaundice, 32 patients with alcoholic liver disease without evidence of cirrhosis, 23 healthy persons and 43 patients with unrelated disease. sIL-2R in patients with cirrhosis (mean +/- s.e.m. 1499 +/- 140 U/ml) and obstructive jaundice (1517 +/- 204) was significantly increased compared with healthy subjects (363 +/- 29) and patients with unrelated diseases (685 +/- 92); sCD8 was significantly increased in patients with cirrhosis (737 +/- 63) but not in patients with obstructive jaundice (419 +/- 32) compared with healthy subjects (322 +/- 23) and patients with unrelated diseases (375 +/- 22). No difference was found between patients with cirrhosis due to alcohol abuse (n = 15) and chronic hepatitis B (n = 6). The Child-Pugh score had no significant influence on the sIL-2R or sCD8 value. In obstructive jaundice, sIL-2R correlated with alkaline phosphatase as marker of cholestasis (r = 0.43). These data show that in spite of the apparent depressed cellular immune defense both in liver cirrhosis and obstructive jaundice there is a general activation of the immune system but the CD8+ cell compartment is only activated in liver cirrhosis. The great changes of sIL-2R and sCD8 in liver dysfunction are important for the interpretation of studies using these serum proteins as markers for immune activation.