Deleted in Azoospermia-Like (DAZL) gene–expressing cells in human amniotic fluid: a new source for germ cells research?

Objective To evaluate whether amniotic fluid cells contain a germ-like cell subpopulation. Design Experimental study. Setting University hospital. Patient(s) None. Intervention(s) Cells from human amniotic fluid samples were analyzed for messenger RNA expression of Deleted in Azoospermia-Like gene (DAZL) and Oct-4 by reverse transcriptase polymerase chain reaction. DAZL and C-kit protein expression was assessed by flow cytometry. Immunocytochemistry also was performed to determine DAZL-, stage-specific embryonic antigen 4 (SSEA-4)-, and Oct-4-positive cells. Main Outcome Measure(s) DAZL gene expression in amniotic fluid cells. Result(s) Reverse transcriptase polymerase chain reaction, flow cytometric, and immunocytochemical analyses revealed that human amniotic fluid consists of a distinct cell population that expresses DAZL, C-kit, SSEA-4, and Oct-4. Conclusion(s) Our results suggest that human amniotic fluid represents a new source for the isolation of human DAZL-, C-kit-, SSEA-4-, and Oct-4-positive stem cells without raising the ethical issues associated with human embryonic research.