Problem: In human decidua, a significant increase of leukocytes including CD56(++)CD16(-) uterine natural killer (uNK) cells and CD14(+) monocytes has been observed with the onset of pregnancy. The mechanisms required for the recruitment of those cells to the uterus are still under debate. Cytokines and chemokines have been suggested as key factors for the regulation of these complex cellular migration and interaction processes.
Method of study: Investigation of the expression patterns of cytokines, chemokines and growth factors in human decidual tissue (7-8 weeks of gestation) was performed by protein array analysis. Isolated decidual leukocytes, i.e. CD56(++)CD16(-) uNK, CD14(+) monocytes as well as cytotrophoblast (CTB) and stromal cells were tested separately.
Results: This analysis revealed the production of monocyte attracting chemokines (GRO, MCP-1), angiogenetic substances (EGF, VEGF, Angiogenin) as well as granulocyte activating peptides (ENA-78, IL-1beta, RANTES, IL-8) by decidual tissue and its cell subsets.
Conclusion: The observed pattern supports the role of decidua as a tissue which promotes angiogenesis, attracts monocytes and modulates the function of the latter.