Lymphocyte transformation by phytohaemagglutinin (PHA) and purified protein derivative (PPD) in primary biliary cirrhosis. Evidence of serum inhibitory factors

Factors inhibitory to lymphocyte transformation in vitro by PHA and PPD have been demonstrated in the majority of sera from patients with primary biliary cirrhosis. These factors inhibited transformation in response to PHA both of autologous lymphocytes, and of `reference' lymphocytes which were obtained from a single donor. `Reference' lymphocyte transformation in response to PPD was significantly less when cultured in sera from both primary biliary cirrhosis patients and control subjects than when cultured in AB serum.