麻省理工大学：《生物材料——组织交互作用》教学讲义（英文版）Chapter 2 Cell-Matrix Interactions

Chapter 2. Cell-Matrix Interactions that determine biomaterials function in vitro and in vivo] A. How cells pull onto and deform the matrix to which they attach themselves B Cell-matrix interactions control the spontaneous closure of wounds in organs. C. What happens when regeneration is induced?

Chapter 2. Cell-Matrix Interactions. [that determine biomaterials function in vitro and in vivo] A. How cells pull onto and deform the matrix to which they attach themselves. B. Cell-matrix interactions control the spontaneous closure of wounds in organs. C. What happens when regeneration is induced?

A. How cells pull onto and deform the matrix to which they attach themselves Cells develop contractile forces individually, not cooperatively Cell elongation, not contraction, eventually leads to matrix deformation Contractile forces are force-imited not displacement-limited

A. How cells pull onto and deform the matrix to which they attach themselves. • Cells develop contractile forces individually, not cooperatively. • Cell elongation, not contraction, eventually leads to matrix deformation. • Contractile forces are force-limited, not displacement-limited

a brief review or relevant structures cell membrane, transmembrane proteins, cell receptors(integrins), cytoplasm, matrix

A brief review or relevant structures: cell membrane, transmembrane proteins, cell receptors (integrins), cytoplasm, matrix

Definition of unit cell process Soluble Requlator A Cell Insoluble Product Soluble Requlator Regulator B Control volume dV Unit cel process confined conceptually in a control volume dv

5 Definition of unit cell process Cell + Insoluble Regulator Product Soluble Regulator A Soluble Regulator B Control volume dV Unit cell process confined conceptually in a control volume dV

a typified cell diagram showing cell-cell binding Image removed due to copyright considerations

A typified cell diagram showing cell-cell binding replace - redraw Image removed due to copyright considerations

Non-polar Cell fatty acic membrane sketch Extracellular showing Oligosaccharide Glycoprotein Peripheral transmem- Glycolipid protein brane Integra otein roteins Hydrophobic polar head Peripheral proteins protein Intracellular

Cell membrane sketch showing transmem￾brane proteins

Specific cell-matrix interaction through integrins Fibronectin, etc Cell Membrane Tatin Vincula After Hynes, 1990

After Hynes, 1990 Specific cell-matrix interaction through integrins Cell Membrane

Another model of a specific cell-matrix interaction Image removed due to copyright considerations Fibronectin molecule shown attaching a cell to the surface of a collagen fiber

Another model of a specific cell-matrix interaction Image removed due to copyright considerations. Fibronectin molecule shown attaching a cell to the surface of a collagen fiber

FIRST ARTICLE See Freyman, T.M., L.V. Yannas, R. Yokoo, and L.J. Gibson Fibroblast contraction of a collagen-GAG matrix Biomaterials22(2001)28832891

FIRST ARTICLE See Freyman, T.M., I.V. Yannas, R. Yokoo, and L.J. Gibson. "Fibroblast contraction of a collagen-GAG matrix." Biomaterials 22 (2001) 2883-2891

Conclusions on Linearity vS Cooperativity of Fibroblast Contraction of matrix The contractile force increases linearly with cell density The average contractile force is calculated at 1 nn per cell The kinetics for development of force are also independent of cell density. In this model cells must develop contractile forces individually, not cooperatively

Conclusions on Linearity vs. Cooperativity of Fibroblast Contraction of Matrix • The contractile force increases linearly with cell density. • The average contractile force is calculated at 1 nN per cell. • The kinetics for development of force are also independent of cell density. • In this model cells must develop contractile forces individually, not cooperatively