Investigation of Mechanical Property of Various Bone Cell Lines by Atomic Force Microscopy

Wang Zhe, Hao Fengtao, Yang Zhouqi, Chen Xiaohu, Shang Peng^*

Key Laboratory for Space Biosciences and Biotechnology, Institute of Special Environmental Biophysics,School of Life Sciences, Northwestern Polytechnical University, Xi’an 710072, China

Abstract: In order to investigate the mechanical property of various bone cell lines and its relation with cell function， atomic force microscopy (AFM) was used to probe the Young’s modulus of pre-osteoblast (2T3 and MC3T3-E1)， pre-osteocyte (MLO-A5) and osteocyte (MLO-Y4). The fluorescent images of cell cytoskeleton such as F-actin and microtubule were detected by laser confocal microscopy. The results demonstrated that the Young’s modulus of 2T3， MC3T3-E1， MLO-A5 and MLO-Y4 cell lines were (7 000±2 015) Pa， (6 600±2 024) Pa， (4 700±1 644) Pa and (4 500±1 622) Pa， respectively. Interestingly， the Young’s modulus of pro-osteoblast was significantly higher than those of MLO-A5 and MLO-Y4， and this tendency of change in the Young’s modulus was consistent with that of primary bone cells in different differentiation states. Meanwhile， the images of cytoskeleton showed that thick bundles of the F-actin and microtubule in 2T3 and MC3T3-E1 were concentrated in peri-nuclear region. But for MLO-A5， especially for the MLO-Y4， the cytoskeletons were mainly distributed in the cell process or cell periphery， which might be one reason to explain the low Young’s modulus in the MLO-A5 and MLO-Y4 cells. This study， for a biomechanical view， provided a basis interpretation for deeply understanding the relationship between
the cell function and their structure.

CSTR: 32200.14.cjcb.2014.05.0013