Thesis
26/10/2017
Amphi D. Escande

Direct reprogramming of somatic cells into human induced naive pluripotent stem cells, a novel model of preimplantation epiblast cells

Stéphanie Kilens

Supervisor

Ignacio Anegon/ Laurent David

Jury

Rapporteurs: Dr. Alice Jouneau et Prof. Jennifer Nichols

Examinateurs: Dr. Thomas Fréour et Dr. Michel Cohen-Tannoudji

Directeurs de thèse: Dr. Ignacio Anegon et Dr. Laurent David

Induced pluripotent stem cells (iPSCs) have considerably impacted human developmental biology and regenerative medicine, notably because they circumvent the use of cells from embryonic origin and offer the potential to generate patient-specific pluripotent stem cells. However, conventional reprogramming protocols produce developmentally advanced, or primed, human iPSCs (hiPSCs), restricting their use to post-implantation human development modelling. Hence, there is a need for hiPSCs resembling preimplantation naive epiblast. Here, we developed a method to generate naive hiPSCs directly from somatic cells using OKMS overexpression and specific culture conditions without transitioning through a primed pluripotent state. Besides, this protocol enables parallel generation of isogenic lines bearing different potencies among which the primed state as it is a major control line. To evaluate the generated naive hiPSCs, we benchmarked them against human preimplantation epiblast and reveal a remarkable concordance in their transcriptome, dependency on  mitochondrial respiration and X chromosome status. Collectively, these results are essential for the understanding of pluripotency regulation throughout preimplantation development and will generate new opportunities for disease modeling and regenerative medicine.