Department of Urology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Department of Urology, Huashan Hospital, FuDan University, Shanghai, China.
BMC Biotechnol. 2021 Feb 2;21(1):11. doi: 10.1186/s12896-021-00672-z.
Human epithelial cell sheets (ECSs) are used to clinically treat epithelial conditions such as burns, corneal blindness, middle ear cholesteatoma and vitiligo. As a widely used material in clinic, there is little information on the biobanking of ECSs and its repair effect after storage.
Two methods for biobanking foreskin ECSs were compared in a short term (7 days): 4-degree storage and programmed cryopreservation. Cell sheet integrity, viability, apoptosis, immunogenicity, mechanical properties and function were evaluated. In vivo, ECSs were directly transplanted to skin defect models and histological examination was performed at 1 week postoperatively. We successfully extracted human foreskin-derived primary epithelial cells and fabricated them into ECSs. Compared with 4-degree storage, programmed cryopreservation preserved the ECS structural integrity, enhanced the mechanical properties, decreased HLA-I expression, and increased cell viability and survival. An increased proportion of melanocytes with proliferative capacity remained in the cryopreserved sheets, and the undifferentiated epithelial cells were comparable to those of the fresh sheets. In vivo, cryopreserved ECSs could reduce inflammatory cell infiltration and promote connective tissue remodeling, epithelial cell proliferation and vascular regeneration.
Programmed cryopreservation of ECSs was superior and more feasible than 4-degree storage and the cryopreserved ECSs achieved satisfying skin wound healing in vivo. We anticipate that the off-the-shelf ECSs could be quickly used, such as, to repair human epithelial defect in future.
人上皮细胞片（ECS）被用于临床治疗上皮疾病，如烧伤、角膜盲、中耳胆脂瘤和白癜风。作为一种广泛应用于临床的材料，关于 ECS 的生物库及其储存后的修复效果的信息却很少。
在短期内（7 天）比较了两种保存包皮 ECS 的方法：4°C 储存和程控冷冻保存。评估了细胞片的完整性、活力、凋亡、免疫原性、力学性能和功能。在体内，将 ECS 直接移植到皮肤缺损模型中，并在术后 1 周进行组织学检查。我们成功地从人包皮中提取了原代上皮细胞，并将其制成 ECS。与 4°C 储存相比，程控冷冻保存了 ECS 的结构完整性，提高了力学性能，降低了 HLA-I 表达，增加了细胞活力和存活率。冷冻保存片中有更多具有增殖能力的黑素细胞，未分化的上皮细胞与新鲜片相似。在体内，冷冻保存的 ECS 可减少炎症细胞浸润，促进结缔组织重塑、上皮细胞增殖和血管再生。
与 4°C 储存相比，ECS 的程控冷冻保存更优且更可行，冷冻保存的 ECS 可在体内实现令人满意的皮肤创伤愈合。我们预计未来这种现成的 ECS 可以快速用于修复人类上皮缺陷。
