LAUSR

Coronary artery disease and heart failure are among the leading causes of mortality in United States and worldwide. The limited proliferation of the adult mammalian heart has prompted the need to recognize novel strategies that can restore contractile function in heart disease. We recently reported that cells expressing trophoblast marker Cdx2 isolated from murine end-gestation placentas are multipotent and immune-privileged, with homing ability to travel to sites of cardiac injury to regenerate injured myocardium. Since murine Cdx2 cells are immunologically naïve and trophoblast-mediated placentation is a conserved phenomenon, our findings are ripe for translational application. Here we demonstrate the expression of CDX2 and isolation of CDX2 cells from human term placentas highlighting a potentially critical cell source for allogeneic therapy for cardiac regeneration. We studied de-identified human term placenta tissues from three different anatomical sites from three different patients. Formalin-fixed paraffin embedded samples, second trimester chorionic villus samples and de-identified fresh chorion samples were utilized. Using a multiparametric approach including transcript analysis and Sanger sequencing, immunoblot and immunofluorescence analysis, with the subsequent screening of different anatomical sites, we observed that CDX2 is present in the chorionic (fetal cytotrophoblast) portion of human term placentas including the chorionic villous samples (CVS). Subsequent validation on positive control cells DLD1 (human colon carcinoma cell line), versus HeLa cells (low endogenous CDX2 expression) was performed. Visualization of CDX2 expression showed the nuclear localization in the villi region. We have further demonstrated using a CDX2 promoter-driven fluorescence-based lentiviral expression system, we can isolate viable CDX2 cells from fresh term placenta. We demonstrate for the first time that CDX2 cells are present and can be isolated from term human placentas for prospective cardiomyocgenic differentiation. A step closer to the translational approach, our results herein may represent a paradigmatic shift in the way we approach early embryonic lineages and cell fate choices towards the identification of an unexplored human cell-based approach for cardiac regeneration.