Determination of the interleukin-2 receptor beta chain by peripheral blood mononuclear cells in patients with primary biliary cirrhosis

Interleukin-2 receptor (IL-2R) beta chain expression was assessed in peripheral blood mononuclear cells (PBMCs) by flow cytometry using an IL-2R beta chain-specific mouse monoclonal antibody in 23 patients with primary biliary cirrhosis (PBC) and 20 normal controls. The percentages of IL-2R beta chain positive cells in PBMCs were significantly decreased in PBC patients compared with those of normal controls (P < 0.01). IL-2R beta chain expression showed no difference between patients with asymptomatic and symptomatic PBC, or among the stages of a histological grading by Scheuer's classification. The IL-2R beta chain was mainly expressed by CD 16 positive cells (natural killer cells) in PBC patients as well as in normal controls. To study the biological significance of the diminishment of the IL-2R beta chain in PBC patients, natural killer (NK) activity and lymphokine activated killer (LAK) activity was determined simultaneously in 12 PBC patients. A significant correlation was observed between the percentage of IL-2R beta chain positive cells and NK activity (r = 0.778, P < 0.01) or LAK activity (r = 0.736, P < 0.01). These findings suggest that the decreased expression of IL-2R beta chain is linked to diminished NK activity and LAK activity in PBC patients. (C) 1997 Elsevier Science Ireland Ltd.