Deutsch
The ability to trigger or turn ‘on/off’ material properties with
external stimuli in order to control biological responses is critically
important to biotechnological and biomedical applications. One such
application is the use of light to trigger cell adhesion to synthetic
materials by controlling the presentation of the bioadhesive
arginine-glycine-aspartic acid (RGD) oligopeptide. Using a
photocleavable caged RGD peptide we have been able to photoactivate
cell adhesion to artificial surfaces. Cell patterns onto different
substrates were obtained, where cell attachment is only driven by the
presence of the photoactivated RGD. This approach is now being used for
more profound studies of cell adhesion phenomena.
Phototriggered cell detachment from surfaces modified with a photocleavable linker
References:
| Caged cell adhesive peptide: the photoremovable group 3-(4,5-dimethoxy-2-nitrophenyl)-2-butyl ester was introduced at the aspartate unit of cyclo(RGDfK), a very active and selective ligand of integrin aVb3. In the caged form the peptide is not recognized by integrins. After irradiation, the activity is restored. | QCM-D shift of frequency (bold lines) and dissipation on crystals modified with cyclo[RGD(DMNPB)fK] and cyclo(RGDfK) demonstrating different affinity of the integrins for the caged and uncaged derivatives. Crystals were first loaded with integrin, followed by a washing step, an irradiation step and a second loading of integrin. |
Novel linkers with an intercalated
photocleavable group allowed us to
revert the cell adhesion process by un-tethering the surface attached
RGD peptide from the surface and releasing adhering cells upon light
exposure. This is the firs light-based approaches able to specifically
promote cell adhesion to materials with the ability to precisely
de-activate or detach the cells at later time points or spatial
locations. This is a relevant issue in cell biology (cells need to be
removed from the culture plate during culture and before application)
and tissue engineering (i.e. cell sheet engineering therapies). Our
strategy is applicable to any material, provided proper linker design,
and provides direct control over the molecular interactions involved in
cell adhesion.
Phototriggered cell detachment from surfaces modified with a photocleavable linker
References:
- Photoactivatable caged cyclic RGD peptide for triggering integrin binding and cell adhesion to surfaces, M. Wirkner, S. Weis, V. San Miguel, M. Álvarez, R. A. Gropeanu, M. Salierno, A., R.E. Unger, C.J. Kirkpatrick, A. del Campo, ChemBioChem (2011) doi: 10.1002/cbic.201100437
- Triggered Cell Release from Materials using Bioadhesive Photocleavable Linkers, M. Wirkner, J. M. Alonso, V. Maus, M. Salierno, T. T. Lee, A. J. García, A. del Campo*, Advanced Materials (2011), 23: 3907–3910. doi: 10.1002/adma.201100925
- Phototriggering of cell adhesion by caged cyclic RGD peptides, S. Petersen, J. M. Alonso, A. Specht, P. Duodu, M. Goeldner, A. del Campo*, Angew. Chem. Int. Ed., 47, 3192-3195 (2008)
