Self-organization, quality control, and preclinical studies of human iPSC-derived retinal sheets for tissue-transplantation therapy
Kenji Watari, Suguru Yamasaki, Hung‐Ya Tu, Masayuki Shikamura, Tatsuya Kamei, Hideki Adachi, Tomoaki Tochitani, Yasuyuki Kita, Aya Nakamura, Kazuki Ueyama, Keiichi Ono, Chikako Morinaga, Take Matsuyama, Junki Sho, Miyuki Nakamura, Masayo Fujiwara, Yoriko Hori, Anna Tanabe, Rina Hirai, Orie Terai, Osamu Ohno, Hidetaka Ohara, Tetsuya Hayama, Atsushi Ikeda, Daiki Nukaya, Keizo Matsushita, Masayo Takahashi, Akiyoshi Kishino, Tōru Kimura, Shin Kawamata, Michiko Mandai, Atsushi Kuwahara
Abstract
Three-dimensional retinal organoids (3D-retinas) are a promising graft source for transplantation therapy. We previously developed self-organizing culture for 3D-retina generation from human pluripotent stem cells (hPSCs). Here we present a quality control method and preclinical studies for tissue-sheet transplantation. Self-organizing hPSCs differentiated into both retinal and off-target tissues. Gene expression analyses identified the major off-target tissues as eye-related, cortex-like, and spinal cord-like tissues. For quality control, we developed a qPCR-based test in which each hPSC-derived neuroepithelium was dissected into two tissue-sheets: inner-central sheet for transplantation and outer-peripheral sheet for qPCR to ensure retinal tissue selection. During qPCR, tissue-sheets were stored for 3-4 days using a newly developed preservation method. In a rat tumorigenicity study, no transplant-related adverse events were observed. In retinal degeneration model rats, retinal transplants differentiated into mature photoreceptors and exhibited light responses in electrophysiology assays. These results demonstrate our rationale toward self-organizing retinal sheet transplantation therapy.