人脐带血清器官培养液保存猪角膜的实验研究

Organ culture for preservation of the cornea: human umbilical cord serum versus fetal bovine serum

目的 观察胎牛血清器官培养液和人脐带血清器官培养液对猪角膜内皮细胞形态学、组织学、超微结构、酶活性及代谢等的影响。方法 器官培养方法:4周以内31℃密闭培养,之后脱水24 h。选择猪眼113只,其中100只角膜分为两组进行配对器官培养保存。第1组(50只角膜):应用培养液Ⅰ(含10％胎牛血清);第2组(50只角膜,第1组的对侧角膜):应用培养液Ⅱ(含10％人脐带血清)。13只角膜作为正常对照。器官培养每周每组各取出12只角膜进行内皮细胞形态学分析、HE染色、酶组织化学染色。保存2周、4周时行扫描电镜检查。检测保存前后培养液的pH值和葡萄糖、乳酸浓度。器官培养过程中行微生物学检测。结果 器官培养期间角膜内皮细胞单层保持完整,多形性增加,两组之间角膜内皮细胞密度、细胞面积的变异系数和六边形细胞比例在保存4周内差异无显著意义。保存4周的猪角膜与正常猪角膜相比,平均内皮细胞丢失率第1组为10.98％,第2组为10.85％。两组角膜器官培养后的组织学、超微结构、酶活性无明显区别。扫描电镜显示内皮细胞层完整,细胞形态改变。酶组织化学染色显示上皮、内皮细胞酶活性旺盛,基质细胞的酶活性随保存时间的延长而降低。角膜代谢状态良好。器官培养液污染率为6％。结论

Objective To evaluate the changes of porcine corneal endothelium, the morphology, histology, ultrastructure, enzymes activity and metabolism of the cornea induced by organ culture with two different media containing fetal bovine serum ( FBS) or human umbilical cord serum (HCS). Methods Fifty pairs of porcine corneas were preserved at 311 for 7, 14, 21, 28 days. One cornea of each pair was cultivated in medium I containing 10% FBS (group 1) ; the other one was stored in medium Ⅱ containing 10% HCS (group 2). Thirteen fresh porcine corneas served as controls. All stored corneas were dehydrated for 24 hours. Twelve corneas from each group were evaluated each week, including the morphology, histology and enzyme histochemical staining of the cornea Scanning electron microscopy was performed on one cornea from each group at 14 and 28 days and compared with the fresh cornea. pH value, glucose and lactate concentration of the culture media before and after culture were examined. Microbiological evaluation was also performed. Results Endothelium evaluation did not differ statistically between the two groups of porcine corneas. The morphological endothelium study showed some alterations such as pleomorphism. After 28 days of cultivation, the mean cell losses of endothelium were 10. 98% and 10. 85% in medium I and medium Ⅱ stored corneas, respectively. There were no statistical differences of the histology, ultrastructure and enzymes activity of corneas between the two groups. The histological study showed corneal swelling and epithelial sloughing after preservation. Scanning electron microscopy showed an intact endothelial layer in all corneas. Enzyme histochemical staining showed vigorous enzyme activity in the corneal epithelium and endothelium. Enzyme activity in stroma decreased with preservation time. Corneas showed good glucose metabolism. Incidence of contamination was 6% for storage medium. Conclusions The corneal endothelium can maintain a good viability for 4 weeks in these two organ culture media. HCS can replace FBS in the organ culture medium. (Chin J Ophthalmol, 2004,40-.533-538)