1例ENU诱变小鼠模型角膜病变分析及致病基因定位

Analysis of the keratopathy characteristics and mapping of the pathogenic gene in an ENU-induced corneal disease mouse model

角膜病是人类第4大致盲眼病。通过乙烷基亚硝基脲(N-ethyl-N-nitrosourea,ENU)诱导小鼠突变建立遗传性角膜病小鼠模型,对角膜病小鼠角膜组织进行病理分析并确定致病基因的染色体位置。HE染色发现:角膜病小鼠角膜基质层出现新生血管及较多的角膜细胞,角膜与虹膜发生粘连。采用免疫组织化学技术检测角膜上皮Keratin 12(K12)、Keratin 14(K14)、Keratin 10(K10)及PAX6的表达情况,结果发现:角膜病小鼠K12信号局部减弱或为阴性,K10局部免疫组织化学染色结果为阳性,K14可表达于整个角膜上皮层且局部信号增强,PAX6阳性细胞明显减少或消失。连锁分析将致病基因定位于小鼠第10号染色体D10Mit162与D10Mit233之间。该研究有望为人类角膜病研究提供一种新的小鼠模型。

Corneal disease is one of the major causes of blindness worldwide.The aim of this study was to create a N-ethyl-N-nitrosourea(ENU)-induced inherited corneal disease mouse model,pathologically analyze the of corneal sections for corneal disease mouse and map the pathogenic gene.HE staining showed corneal neovascularization,proliferation of keratocytes and iridocorneal adhesion in mutant corneas.Immunohistochemistry showed that Keratin 12(K12)was present in the corneal epithelium in the control corneas,but it was absent in some region of the mutant corneas.In mutant corneas,Keratin 10(K10)was expressed,and Keratin 14(K14)was expressed most prominently in the corneal epithelium.However,K10 was not expressed and K14 was weakly expressed in the wild-type corneal epithelium.In wild-type mice,PAX6 was expressed in the corneal or reduced to low epithelium.In contrast,PAX6 expression was almost abolished in the pathological cornea levels in a few cells.The pathogenic gene was mapped to mouse chromosome 10 between makers D10Mit162 and D10Mit233.The strain might be used as a mouse model for the study of human heritable corneal diseases.