Modulation of perforin expression in the decidual and peripheral blood cytotoxic lymphocytes in culture

PROBLEM: Perforin (P) is a cytolytic molecule located in intracellular gran ules of cytotoxic lymphocytes both in the peripheral blood and decidua of p regnancy. The aim was to analyze the kinetics of P expression during in vit ro culture and modulation of P expression by adherent cells, their supernat ants and mitogen (PHA) stimulation. METHOD OF STUDY: P (intracellular antigen) was detected by flow cytometry i n the suspension of first trimester pregnancy peripheral blood lymphocytes (PBL) and decidual lymphocytes (DL). RESULTS: A decrease of the percentage of P+ tells was obtained after 1 hr i ncubation and was prevented by addition of 30% of decidual adherent cells ( DAC) or their supernatants. Upregulation of P expression was obtained when, in addition to adherent cells, DL and PBL were stimulated by PHA. DAC pres ent in the culture in physiological concentrations; prevent downregulation of P expression. CONCLUSION: DAC located in the vicinity of decidual cytotoxic lymphocytes, owing to their unique ability to produce a wide range of substances on dema nd, contribute to the high level of P expression in the decidua of pregnanc y.