T lymphocyte subsets in the peripheral blood in patients with primary biliary cirrhosis.

T lymphocyte subsets and natural killer (NK) cells in the peripheral blood of 10 patients with primary biliary cirrhosis (PBC) were examined by using various kinds of monoclonal antibodies directed to the surface markers of the lymphocytes. We found that the population of Leu 2a+, Leu 15- cytotoxic T cells was decreased in PBC patients compared to normal controls, especially in those with a high serum titer of anti-mitochondria antibodies. However, there was no significant difference in the population of Leu 2a+, Leu 15+ suppressor T cells between PBC patients and normal controls. Although the population of Leu 3a+, Leu 8- helper T cells was not significantly different, the population of Leu 3a+, Leu 8+ suppressor-inducer T cells was remarkably increased in PBC patients compared to normal controls. On the other hand, no such difference was seen for the NK cells. Furthermore, the Leu 3a+/Leu 2a+ ratio was significantly higher in PBC patients especially in those with a high serum anti-mitochondria antibody titer, which was thought to be due to the decreased population of cytotoxic T cells.