正常人眼角膜上皮细胞的原子力显微镜观察  

Observation of Human Normal Eye Corneal Epithelial Cell by AFM

作　　者：蔡小芳[1] 杨筱曦[2] 蔡继业[1] 邓华[1] 

机构地区：[1]暨南大学化学系,广东广州510632 [2]暨南大学附属第一医院眼科,广东广州510632

出　　处：《分析测试学报》2009年第8期881-885,共5页Journal of Instrumental Analysis

基　　金：海外及港澳学者合作研究基金资助项目(30828028);国家自然科学基金重点资助项目(30230350)

摘　　要：应用原子力显微镜(AFM)在单细胞水平上分析了人眼角膜上皮细胞的形貌和机械性质,为进一步探讨人眼角膜上皮细胞结构与功能的关系奠定了基础。将体外培养的人眼角膜上皮细胞用2.5%戊二醛固定,空气中干燥后用原子力显微镜进行观察。从AFM形貌图可知,细胞呈长梭形,膜表面布满颗粒状物质,由AFM附带软件IP2.1的线分析及面分析功能,得到细胞膜表面结构的几何参数,包括高低差Rp-v、均方根粗糙度Rq、平均粗糙度Ra、平均高度Meant Ht。利用AFM高空间分辨的力位移曲线测量系统,可得出细胞膜的粘弹力、硬度和杨氏模量。AFM能对人眼角膜上皮细胞表面的超微结构清晰地成像并提供更多更确切的表面信息,从另一层面增加对眼角膜上皮细胞的认识。The morphology and mechanical property of human normal eye corneal epithelial cell were analyzed by atomic force microscope （AFM） at single-cell level. These results laid a foundation for detecting the relationship between structure and function of the ceil. The cells were fixed with 2.5% glutaraldehyde and air-dried. Then the cells were detected by AFM with contact mode. At least 20 cells were observed. The images showed that the shape of the cells presented long fusiform and there were granular packed particles on the cell membrane. The sizes of the particles were about 100 nm. These particles produced by the accumulation of membrane proteins and lipopolysaccharides. With the region analysis function of IP2. 1 software, the regions of 1 μm × 1 μm were selected and four parameters e. g. maximum peak-to-valley distance（Rp-v） , root-mean-squared roughness（Rq）, average roughness （Ra） and mean height （ Meant Ht） of the cells were measured. The data of Rp-v, Rq, Ra and Meant Ht were 72.49 ±＋25. 84, 19. 2±7. 14, 15.92 ±6. 03 and 91.56 ± 18.72 nm, respectively. From the high spatial resolution of AFM force-curves, the mechanical properties （adhesion force, stiffness and Young＇s modulus） of the cells were obtained. The data of adhesion force were around 1 000 pN, stiffness were 1.15 ±0. 267 mN/m and Young＇s modulus were 8.86±3.47 kPa. It was concluded that AFM had specific advantages in analyzing cell membrane at nanometer level and could provide more precise information, which helped us increase the awareness of cornea epithelial cells at visualization level. In the other hand, these results also promoted the AFM to apply in the biomedical and clinical field.

关 键 词：原子力显微镜 人眼角膜上皮细胞 形貌 粘弹力 硬度 杨氏模量 

分 类 号：O766.1[理学—晶体学] Q246[生物学—细胞生物学]