Leveraging chorionic villus biopsies for the derivation of patient-specific trophoblast stem cells

Human trophoblast stem (TS) cells are an informative in vitro model for the generation and testing of biologically meaningful hypotheses. The goal of this project was to derive patient-specific TS cell lines from clinically available chorionic villus sampling (CVS) biopsies. Cell outgrowths were captured from human CVS tissue specimens cultured in modified human TS cell medium. Cell colonies emerged early during the culture and cell lines were established and passaged for several generations. Karyotypes of the newly established CVS-derived trophoblast stem (TSCV) cell lines were determined and compared to initial genetic diagnoses from freshly isolated chorionic villi. Phenotypes of TSCVcells in the stem state and following differentiation were compared to cytotrophoblast-derived TS (TSCT) cells. TSCVand TSCTcells uniformly exhibited similarities in the stem state and following differentiation into syncytiotrophoblast. These shared features included morphology and gene expression. TSCVcell differentiation into extravillous trophoblast cells exhibited cell line dependent phenotypes. CVS tissue specimens provide a valuable source for TS cell derivation. They expand the genetic diversity of available TS cells and are associated with defined clinical outcomes. TSCVcell lines provide a new set of experimental tools for investigating trophoblast cell lineage development.