Cardiac Microenviroment Program Human Aminotic Fluid‐derived Stem Cell To Cardiac Phenotype

Abstract

ObjectiveIt is believed that certain microenvironment can induce differentiation of stem cell into a specific cell lineage. Therefore, we carried out in vitro coculture experiments to investigate the potential of human amniotic fluid‐derived stem cell (hAFS) to differentiate along cardiac lineage. Our long‐term goal is to explore the feasibility of using this cell source for cardiac cell therapy.MethodsNeonatal rat Cardiomyocytes (NRVM) were obtained by enzymatic digestion of ventricles from neonatal Sprague‐Dawley rats and plated on 1% gelatin coated coverslips. hAFS cells were labeled by PKH26, cultured directly with NRVM. At different time interval, cells were stained with cardiac specific antibodies. For dye transfer experiment, NRVM were preloaded by calcein‐AM and cocultured with PKH26 labeled hAFS.ResultsAs early as 24 hours after initiation of coculture, contracting PKH26‐positive cells were observed. However, their number was low. After 14 days of coculture, immunostaining detected PKH26 positive cells colocalized with cardiac myosin heavy chain, cardiac Troponin T and connxin 43 positive cells. We further conducted dye transfer experiments to test coupling between NRVM and hAFS cells. 18 hour after initiation of coculture, calcein‐AM and PKH26 dual positive cells was observed, suggesting the existence of coupling between the two cell types, possibly through connexin 43.