Generation of a functional, patient specific human thymus from induced pluripotent stem cell in vivo

Here we describe a universal direct differentiation protocol that allows the generation of thymic epithelial progenitor cells (TEPs) from different iPSC lines. Upon transplantation into an athymic mouse model, TEPs further differentiate into thymic epithelial cells (TECs). TECs are functional and can facilitate the education of developing mouse T-cells. iPSC derived, patient specific TECs residing within grafts are indistinguishable from TECs present in human primary neonatal thymus tissue as revealed by single cell RNA sequencing analysis indicating the generation of a mature TEC phenotype. Taken together, we provide a universal direct differentiation protocol that generates TEPs from all iPSC lines tested, that can further differentiate into mature, functional TECs. We anticipate that these findings have important implications for current efforts aimed at generating a functional human thymus. Generatiion of a universal direct differentiation protocol for the generation of thymic epithelial progenitors from human iPSCs. Further, analysis of human iPSC derived thymic epithelial progenitors and in vivo matured thymic epithelial cells by single cell and bulk RNA sequencing.