Samoila Ovidiu, Gocan Diana
Department of Ophthalmology, "Iuliu Haţieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania.
Front Med (Lausanne). 2020 Feb 18;7:43. doi: 10.3389/fmed.2020.00043. eCollection 2020.
Total bilateral limbal stem cell deficiency results from various pathologies, from burns (either chemical or physical) to Sjogren Syndrome, aniridia or ocular cicatricial pemphigoid. After the loss of stem cells, normal corneal epithelium is replaced by a more opaque and vascularized conjunctival epithelium, causing loss of vision. After 1997, cultivation techniques for limbal stem cells became possible. In parallel, cultivation techniques for oral mucosa epithelial cells were also available. The aim of our review was to summarize the clinical outcomes following allogenic cultured limbal stem cell transplant (allogenic CLET), and on the other hand, oral mucosa derived epithelium transplant (cultivated oral mucosa epithelial transplant-COMET or cultivated autologous oral mucosal epithelial cell sheet-CAOMECS), in the case of total bilateral limbal stem cell loss. Thirty studies matching the inclusion criteria were found. The clinical improvement in both methods was reported similar, with percentages higher than 50% of the treated cases. However, the comparison between studies was difficult to achieve due to the lack of a universal and objective grading tool for assessing post-operative results. The definition of clinical improvement was problematic, because success was defined differently, depending on the study. Moreover, some of the studies followed both autologous and allogenic CLET, but described the results together, for both procedures, and therefore it was impossible to analyze them separately. COMET presented some advantages compared to CLET. By using autologous cells, there was no risk of immune activation and no immunosuppression was needed. COMET, however, might be associated with increased risk of persistent epithelial defects and graft failure, compared with allogenic CLET.
双侧完全性角膜缘干细胞缺乏可由多种病理情况引起，从烧伤（化学或物理性）到干燥综合征、无虹膜或瘢痕性类天疱疮。干细胞丧失后，正常角膜上皮被更混浊且血管化的结膜上皮取代，导致视力丧失。1997年后，角膜缘干细胞培养技术成为可能。与此同时，口腔黏膜上皮细胞培养技术也已具备。我们综述的目的是总结在双侧完全性角膜缘干细胞丧失情况下，异体培养角膜缘干细胞移植（异体CLET）以及另一方面口腔黏膜来源上皮移植（培养口腔黏膜上皮移植-COMET或培养自体口腔黏膜上皮细胞片-CAOMECS）后的临床结果。共找到30项符合纳入标准的研究。两种方法的临床改善情况报告相似，治疗病例的改善率高于50%。然而，由于缺乏评估术后结果的通用且客观的分级工具，研究间的比较难以实现。临床改善的定义存在问题，因为不同研究对成功的定义不同。此外，一些研究同时进行了自体和异体CLET，但将两种手术的结果合并描述，因此无法分别进行分析。与CLET相比，COMET有一些优势。通过使用自体细胞，不存在免疫激活风险，也无需免疫抑制。然而，与异体CLET相比，COMET可能与持续性上皮缺损和移植失败的风险增加有关。
