Detection of perforin in human peritoneal fluid T-lymphocytes

Perforin is a specific marker of functionally active cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells. The purpose of this study was to detect perforin-positive lymphocytes in ascites secondary to various gynecologic malignancies and nonneoplastic conditions.

Fifty-three unselected peritoneal fluid specimens submitted for cytopathologic diagnosis were used. A monoclonal antibody to human perforin was used to examine its expression in mononuclear cells from ascites specimens using a standard immunoperoxidase technique.

Strong perforin expression by 15-30% of mononuclear cells was detected in 10 of the 13 patients with severe alcoholic hepatitis, 3 of the 5 patients with chronic active hepatitis without cirrhosis and 1 patient with an autoimmune disorder of unknown etiology. The lymphocytes showed variable positivity for T cell markers (CD2, CD4, CD8 and CD56). Perforin was not detected in ascites specimens obtained from patients with such nonneoplastic disorders as cirrhosis or end stage renal or cardiac failure. Similarly, ascites specimens from patients with various gynecologic malignancies were negative for perforin-positive lymphocytes.

The detection of cytotoxic lymphocytes in peritoneal fluid obtained from patients with liver injury may have implications for the pathogenesis of this disease.