基于NRL基因敲入的人类胚胎干细胞定向分化为视杆细胞

Cell-based therapeutics offer novel option for the treatment of retinitis pigmentosa diseases(RP), a comongenetic eye disorder.The major cause of RP is the progressive dysfunction and death ofretinal photoreceptors (PR).Functional impairment or loss of rod photoreceptors is an earlyclinical manifestation in most retinal neurodegenerative diseases that eventually results in cone cell death and blindness. Notably, Cell-based therapeutics would be akey strategy for PR by offering nomal functional rod photoreceptors. In this project we will take advantage of special cell line, human embryonic stem cells (hESC) line with NRL knock-in. Specially, single NRL, one rod specific expression gene, allele has been targeted with red fluorescent protein(RFP) coding gene.The differentiation of the hESC were being traced by the expression of RFP under the endogenous promoter of NRL.With the 3D retina differentiation, regulating microRNAs and up-regulation or down-regulation of the related signaling pathways, an optimal rod photoreceptors differentiation platform will be established, which also will reveal the molecular insights of rod development.The performance of the present project will address the source issue of rod donors and pave a way for the application of cell-based therapeutics for RP.

视网膜色素变性(Retinitis Pigmentosa, RP)是眼科临床上最常见和最棘手的疾病之一，目前没有好的临床治疗方法。RP以视网膜光感受器细胞功能丧失最为常见，而视网膜光感受器细胞中视杆细胞功能损伤或死亡是RP的早期表现。目前有报道，通过移植大量的视网膜光感受器细胞（视杆细胞）可以恢复动物疾病模型的视力，但是患者对应的细胞治疗缺乏大量的视杆细胞。因此本研究拟利用NRL基因敲入的人类胚胎干细胞定向分化为视杆细胞。具体利用3D(Three-dimension)培养结合调控microRNA和相关信号通路的人为干预，探索从人类胚胎干细胞定向分化为视杆细胞的分化方法。该研究为人类视杆细胞的发育提供新的线索。本项目的开展将为解决视网膜色素变性细胞治疗供体细胞来源提供新的思路,并为利用细胞治疗方法来治疗视网膜色素变性疾病奠定基础。

手术切除、放疗和化疗等治疗后仍能导致高复发概率是胶质母细胞瘤GBM (Glioblastoma)致死性极高的重要原因，直接导致患者的中位生存期不足2年。这种复发不仅发生在原发部位和其周围，远端部位的复发也时常可见。我们的研究表明，视神经分化因子NRL(neural retina leucine zipper)低表达于高级别胶质瘤，并与患者的预后显著相关。下调NRL导致胶质瘤细胞增殖水平提高，同时干性增加。小鼠原位移植瘤模型表明NRL下调可以促进肿瘤细胞的转移。转录组测序显示 NRL下调导致NODAL、NGFR、WNT、BMP等干性与浸润性转移相关信号通路基因的高表达。体外侵袭实验证明NRL下调的胶质瘤细胞可以被NGF高表达的星形细胞所趋化。基于此，我们推测NRL调控GSC干性维持及侵袭相关基因的表达，进而在弥漫型胶质瘤的形成与维持中起到重要作用。