Feng Xu, Ph.D.
Professor, School of Life Science and Technology
Xi’an Jiaotong University
fengxu@mail.xjtu.edu.cn
Biography:
Dr. Xu’s current research aims at advancing human health through academic excellence in education and research that integrates engineering, science biology and medicine with focus on Bio-thermo-mechanics, Engineering of Cell Microenvironment, and Point-of-Care Technologies. Dr. Xu has published more than 160 journal papers, 5 books, 10 book chapters, 120 conference papers/abstracts, together with more than 20 invited talks. Total impact factor is more than 560 and the papers have been cited more than 2400 times, with H-index factor of 24. He was invited as Special Issue Guest Editors for Philosophical Transactions of the Royal Society A in 2009, and for Biotechnology Journal in 2011. Dr. Xu serves an Associate Editor for Journal of Medical Imaging and Health Informatics (JMIHI) and ASME Journal of Nanotechnology in Engineering and Medicine (JNEM), an Editor for Journal of Mechanics in Medicine and Biology (JMMB), Biofabrication, and Scientific Reports. Dr. Xu has also organized and co-chaired 4 international conference and workshops, and served as session chiars 10 times.
Topic title: Engineering Cell MechanicalMicroenvironment
Abstract: Cells in vivo reside within acomplex microenvironment that is rich in biological, chemical and mechanicalcues, playing critical roles in regulating cellular activities (e.g.,proliferation, migration, differentiation) both spatially and temporally.Although it is well accepted that biological and chemical cues cansignificantly influence cell functions, more and more evidence has also shownthat mechanical feedback from the cell microenvironment (e.g., stiffness ofECM, morphology, and tension force) also play an important role in controllingthe fate of cells. Disequilibrium of mechanical microenvironment can cause aseries of diseases, such as cancer migration and cell fibrosis. Thus, there isa pressing need to understand how cells transduce these the nature of theirenvironment, especially mechanical elements such as elasticity, viscosity andviscoelasticity, viscoplasticity into biochemical cues.
Using today’s microand nanoscale technologies and novel biomaterials especially hydrogels, we havedeveloped various approaches to create synthetic but native-like conditions tounderstand cell behavior. Most research involving human cell manipulation hasbeen carried out on artificial two-dimensional (2D) substrates. However, recentstudies showed that cells respond and behave differently in these 2D settingscompared to in 3D intricate microenvironment that cells reside in. Therefore,we have developed innovative 3D in vitro cellular models with well-controlledmechanical microenvironment for re-creating distinct niches and in vitro cellmodeling under well-defined and reproducible conditions.
Besides, we have alsoproposed some cellular mechanosensing mathematical models to describe threemain mechanosensing processes including mechanosensing behaviors on thecell-ECM interaction, mechanochemical conversion in the cytoplasm and nuclearpore enlargement due to the increase of cellular tension: (i) The improvedmotor-clutch model and integrin clustering model to described the FA dynamicson the cell-ECM interface to sense the substrate the mechanical properties;(ii) The signaling pathway model to describe the cytoplasmic signaltransduction and stress fiber reconstitution; (iii) an integrated mathematicalmodel to describe the YAP/TAZ nucleocytoplasmic shuttling dynamics. Thesemathematical models above are able to capture the breadth of mechanobiologicalresponses known to govern the behavior of animal cells. By using today’s micro and nanoscaletechnologies (e.g., microfluidics, lithographic approaches and micromoldingtechnologies), they will further instructionally contribute to engineering cellmechanical microenvironment in vitro to reconstruct the native cellularbehaviors and functions for various applications, such as tissue engineeringand regenerative medicine.
References
[1] Cheng, B., Lin, M., Li, Y.H., Huang, G.Y.,Genin, G.M., Deshpande, V., Lu, T.J. & Xu, F., “An integrated stochasticmodel of matrix stiffness-dependent filopodial dynamics”, Biophysical Journal,111(9), page 2051-2061, (2016).
[2] Cheng, B.,Lin, M., Huang, G.Y., Li, Y.H., Ji, B.H., Genin, G.M., Deshpande, V.S., Lu,T.J. & Xu, F., “Cellularmechanosensing of the biophysical microenvironment: A review of mathematicalmodels of biophysical regulation of cell responses”, Physics of Life Reviews, 22, page 88-119, (2017).