RESUMO
OBJECTIVE: To establish in vitro culture procedure for human amniotic fluid-derived CD117 positive stem cells, and to identify the characteristics of CD117 positive stem cells. METHODS: 86 amniotic fluid samples (10 mL of each) were obtained by second-trimester amniocentesis. Isolation of amniotic fluid-derived stem cells expressing CD117 antigen was performed via magnetic cell sorting using the CD117 MicroBead Kit. The karyotype of CD117 positive stem cells was analysed through repeated freezing. Adipogenic differentiation of these CD117 positive stem cells was displayed by Oil Red O staining. Osteogeneic differentiation of these CD117 positive stem cells was confirmed by Alizarin Red staining. RESULTS: The CD117 positive stem cells were successfully isolated and cultured from 61 samples, with all showing normal karyotype. Product analysis of specific staining confirmed that under specific culture mediums, these cells could be successfully induced to differentiate into adipocytes and osteocytes. CONCLUSION: Based on this study, we estimate that isolating CD117 positive stem cells from second-trimester amniotic fluid obtained by amniocentesis has a success rate of 70.93%. These cells maintain morphological and genetic stability in vitro. Human amniotic fluid-derived CD117 positive stem cells have the ability to differentiate in vitro into adipocytes and osteocytes under specific culture mediums and may be applied in cell transplantation and regenerative medicine.