Problem: We have shown that addition of decidual adherent cells (DAC) to the culture of decidual lymphocytes (DL) prevents the downregulation of perforin expression in these cells. Because DAC are a mixture of various cell populations, the aim is to analyze immunophenotypic characteristics of DAC and to determine which cell population is involved in the regulation of perforin expression.
Method of study: First trimester pregnancy decidual cells were obtained by enzymatic tissue digestion. Decidual cells and peripheral blood lymphocytes (PBL) were centrifuged on Ficoll-Hypaque density gradient and cultured overnight to obtain adherent cells, which were analyzed by flow cytometry and immunocytochemically.
Results: Almost all peripheral blood adherent cells (PBAC) (ca 90%) expressed monocyte/macrophage markers but only 10-20% of DAC. The rest of DAC expressed markers of stromal cells. HLA-DR depleted population of DAC (stromal cells only) could not prevent downregulation of perforin expression in cultured DL and PBL.
Conclusion: Decidual macrophages are involved in the regulation of perforin expression in DL.