Objective: To explore the existence of side-population cells (SP cells) in human decidual tissues in early pregnancy, and its biological characteristics.
Methods: Decidual cells were obtained by enzymatic digestion from the decidual tissues of human early pregnancy. The cells then were stained with Hoechst33342 dye either alone or in combination with verapamil. Fluorescence-activated cell sorter (FACS) analysis was used to identify and isolate SP cells. The isolated cells were cultured in conditioned media culture to observe the proliferation and ability to form colony.
Results: Stem cells were found in the decidual tissues of early pregnancy with a percentage of 0.78% +/- 0.71% (0% - 3.20%). These cells further proliferated and formed colonies during long-time culture in vitro. No significant statistical difference was found in contents of SP cells among different gestational week (P > 0.05).
Conclusion: SP cells exist in human decidua that can further proliferate and have the clonogenicity in culture in vitro.