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Published on: April 23, 2017
Integrin organization: linking adhesion ligand nanopatterns with altered cell responses
W A Comisar1, D J Mooney, J J Linderman
1Department of Chemical Engineering, University of Michigan, 2300 Hayward Street, 3074 HH Dow Bldg, Ann Arbor, MI 48109, USA.
Journal of Theoretical Biology
|January 25, 2011
Summary
Nanopatterned arginine-glycine-aspartic acid (RGD) on biomaterials influences cell behavior by controlling integrin clustering. Different RGD nanopatterns dictate cell spreading, focal adhesion kinase phosphorylation, and osteogenic differentiation.
Area of Science:
- Biomaterials Science
- Cell Biology
- Integrin Signaling
Background:
- Integrin receptors mediate cell adhesion to extracellular matrix ligands like arginine-glycine-aspartic acid (RGD) peptides.
- Nanopatterned RGD on biomaterials can alter cell responses, despite feature sizes smaller than adhesion complexes.
Purpose of the Study:
- To investigate the relationship between RGD nanopatterns and osteoblast responses.
- To computationally model integrin binding to RGD nanopatterns and quantify cell surface integrin organization.
- To correlate in silico integrin organization with in vitro cell behavior.
Main Methods:
- Utilized an extensive dataset of osteoblast responses to RGD nanopatterns.
- Employed a computational model to simulate integrin binding and organization on nanopatterned surfaces.
- Quantified integrin organization at multiple length scales using in silico methods.
- Developed a correlative model linking integrin organization to cell responses.
Main Results:
- Cell spreading correlated with the total number of bound integrins.
- Focal adhesion kinase (FAK) phosphorylation was associated with small, homogeneous integrin clusters.
- Osteogenic differentiation correlated with large, heterogeneous integrin clusters.
Conclusions:
- Biomaterial surface engineering at the nanolevel is crucial for controlling cell behavior.
- Specific patterns of integrin organization, dictated by RGD nanopatterns, are linked to distinct cell responses.
- Findings provide insights into the mechanisms connecting integrin organization to cell fate decisions.
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