ｉＰＳ網膜細胞、５０人へ移植　対象疾患広げ検証―神戸市立病院

　人工多能性幹細胞（ｉＰＳ細胞）から作製した網膜の細胞を含む液体を、目の病気の患者に移植する神戸市立神戸アイセンター病院の臨床研究計画が２０日、厚生労働省の専門部会で了承された。同病院は５０人を目標に移植手術を実施し、新しい治療法としての効果を検証する。
　対象となるのは、「網膜色素上皮（ＲＰＥ）細胞」の異常が原因で起きる病気の患者。同細胞は、光を感じる視細胞に栄養を送る役割があり、変性や機能低下により目が見えにくくなるさまざまな病気を引き起こす。
　理化学研究所などのチームは２０１４年と１７年、世界初のｉＰＳ細胞移植を実施。目の疾患「滲出（しんしゅつ）型加齢黄斑変性」の患者で一定の安全性を確認した。
　新たな研究では、加齢黄斑変性の「萎縮型」など、ＲＰＥ細胞の異常が原因で起こる「ＲＰＥ不全症」の患者全般に対象を広げる。患者数は数万人と推定される。（2021/01/20-21:32）

A committee under the Japanese health ministry approved Wednesday a hospital's plan to conduct clinical research on transplanting liquid containing retinal cells made from induced pluripotent stem, or iPS, cells into patients with eye diseases.
   Kobe City Eye Hospital in Kobe, the capital of Hyogo Prefecture, western Japan, aims to carry out such transplants on 50 patients to examine the effect of the method as a new way of treatment.
   Subject to the clinical research will be patients with diseases caused by abnormalities in retinal pigment epithelial, or RPE, cells. Degeneration and functional deterioration in RPE cells cause a variety of vision-threatening diseases, as the cells deliver nutrients to photoreceptor cells, which respond to light.
   In 2014 and 2017, a team led by Japanese government-affiliated research institute Riken conducted transplants of iPS cells into patients with exudative age-related macular degeneration, an intractable eye disease which causes the worsening of vision, and confirmed the safety of the therapy to a certain extent.
   The clinical research by Kobe City Eye Hospital will cover a wide range of diseases attributed to RPE cell abnormalities, including atrophic age-related macular degeneration. Tens of thousands of people are believed to be suffering from such diseases in Japan.