title: Detection of lipopolysaccharide induced inflammatory responses in RAW264.7 macrophages using atomic force microscope.
abstract: In recent years, LPS activated RAW264.7 cells are widely used as an in vitro inflammatory model for the screen of effective anti-inflammation drugs and the investigation of exact anti-inflammation mechanism of these drugs. But up to now, there are few data about the effect of LPS on the morphology, especially on the membrane ultrastructure and bio-mechanical properties of RAW264.7 macrophages. In this work, the topographical and biophysical changes of RAW264.7 macrophages upon LPS stimulation are detected by high resolution atomic force microscopy (AFM). The AFM results suggested that LPS activated RAW264.7 macrophages changed to be much bigger than control cells with some holes emerged on cell surface. The size of membrane protein clusters and the roughness of membrane significantly increased after LPS exposure. In addition, the AFM force measurement results demonstrated that LPS stimulation increased the adhesion force of RAW264.7 macrophages, and also increased the stiffness of RAW264.7 macrophages, which were attributed to the re-distribution of intracellular F-actin structures induced by LPS. These findings suggested that LPS stimulation could also induce the pathophysiological changes of RAW264.7 macrophages, which would benefit our understanding of the inflammatory processes in macrophages upon pathogen stimulation at nano-scale.
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Pi
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China.
authors.forename: Jianxin
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Su
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou 510632, China.
authors.forename: Fen
authors.initials: F
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou 510632, China.
authors.forename: Haihua
authors.initials: H
authors.lastname: Bai
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou 510632, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Jin
authors.affiliation: State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technology, Macau 000853, China. Electronic address: tjycai@jnu.edu.cn.
authors.forename: Jiye
authors.initials: J
authors.lastname: Cai
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D002460:Cell Line; D007249:Inflammation / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology*; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008264:Macrophages / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D018625:Microscopy, Atomic Force / Q000379:methods
chemical_list: D000199:Actins; D008070:Lipopolysaccharides
keywords: Atomic force microscopy; Inflammatory model; Lipopolysaccharide; RAW264.7 macrophages