Salla Sabine, Kruse Friedrich E, Walter Peter, Menzel-Severing Johannes
Department of Ophthalmology, RWTH Aachen University, Aachen, Germany.
Department of Ophthalmology, University of Erlangen-Nuremberg, Erlangen, Germany.
Cell Tissue Bank. 2019 Jun;20(2):193-200. doi: 10.1007/s10561-019-09757-8. Epub 2019 Feb 23.
To assess corneal endothelial cell (CEC) quantity and quality in eye-bank prepared lamellar grafts for Descemet Membrane Endothelial Keratoplasty (DMEK) from organ cultured donor corneas that have not undergone de-swelling by media supplementation with dextran. Prior to graft preparation, corneas that had not undergone de-swelling (n = 30) were placed into fresh storage medium without dextran (KMI). Corneas in the control group (n = 30) were placed in dehydration medium containing 5% dextran (KMII). Subtotal stripping of Descemet's membrane (DM) was performed manually. Following graft preparation, 10 corneas of each group were cultured further in their respective medium for 24 h, 72 h, or 120 h, respectively. Before and after DM stripping, as well as at the end of culture, CEC numbers were obtained. At the end of culture, CEC morphology was graded using a scoring system and CEC metabolism was assessed by detection of adenosine triphosphate. At 24 h after DM stripping, mean CEC counts (in cells/mm) were 2204 in corneas stored in KMII, and 2391 in corneas stored in KMI (p = 0.003). This corresponds to a mean relative CEC loss of 12.4% with dextran versus 9.7% without dextran (p = 0.04). At 72 h, CEC counts were 1946 in KMII, and 2289 in KMI (p = 0.004). This corresponds to CEC loss of 23% with dextran versus 14% without dextran (p = 0.009). At 120 h, CEC counts were 2047 in KMII, and 2230 in KMI (p = 0.14). This corresponds to CEC loss of 22.7% with dextran versus 17.2% without dextran (p = 0.14). Also, at 120 h after DM stripping, 6/10 corneas fell below a threshold of 2000 cells/mm if stored in medium containing dextran, versus 1/9 corneas if stored without dextran (p = 0.003). Morphological assessment of CEC quality revealed equal scores for cell polymorphism (median = 1), granulation (median = 0) and segmentation (median = 1) in all groups. Lower ATP/protein ratios were observed in corneas stored in medium without dextran at 24 h (p < 0.001), 72 h (p < 0.001), and 120 h (p = 0.02). Abandoning the use of dextran in corneas destined for DMEK surgery leads to increased CEC counts and thereby serves to reduce tissue loss.
评估眼库中为Descemet膜内皮角膜移植术（DMEK）准备的板层移植物中角膜内皮细胞（CEC）的数量和质量，这些移植物来自未通过补充右旋糖酐的培养基进行消肿处理的器官培养供体角膜。在移植物制备前，将未进行消肿处理的角膜（n = 30）放入不含右旋糖酐的新鲜储存培养基（KMI）中。对照组的角膜（n = 30）放入含有5%右旋糖酐的脱水培养基（KMII）中。手动进行Descemet膜（DM）的部分剥离。移植物制备后，每组10个角膜分别在各自的培养基中进一步培养24小时、72小时或120小时。在DM剥离前后以及培养结束时，获取CEC数量。培养结束时，使用评分系统对CEC形态进行分级，并通过检测三磷酸腺苷评估CEC代谢。DM剥离后24小时，储存在KMII中的角膜平均CEC计数（细胞/mm）为2204，储存在KMI中的角膜为2391（p = 0.003）。这相当于使用右旋糖酐时CEC平均相对损失为12.4%，不使用右旋糖酐时为9.7%（p = 0.04）。72小时时，KMII中的CEC计数为1946，KMI中的为2289（p = 0.004）。这相当于使用右旋糖酐时CEC损失23%，不使用右旋糖酐时为14%（p = 0.009）。120小时时，KMII中的CEC计数为2047，KMI中的为2230（p = 0.14）。这相当于使用右旋糖酐时CEC损失22.7%，不使用右旋糖酐时为17.2%（p = 0.14）。同样，在DM剥离后120小时，如果储存在含右旋糖酐的培养基中，10个角膜中有6个低于2000细胞/mm的阈值，而不使用右旋糖酐储存时9个角膜中有1个低于该阈值（p = 0.003）。CEC质量的形态学评估显示，所有组在细胞多态性（中位数 = 1）、颗粒形成（中位数 = 0）和分段（中位数 = 1）方面得分相同。在24小时（p < 0.001）、72小时（p < 0.001）和120小时（p = 0.02）时，储存在不含右旋糖酐培养基中的角膜观察到较低的ATP/蛋白质比率。在用于DMEK手术的角膜中放弃使用右旋糖酐会导致CEC计数增加，从而减少组织损失。
