Molecular dynamics at cell-biomaterial interface
Prof. Dr.
Altankov, George
(ICREA Research Professor)
Group Leader
Pavelló Govern 1ª Planta | Campus de Bellvitge | Feixa Llarga, s/n | 08907 | L'Hospitalet de Llobregat
Email : george.altankov
icrea.cat
Research Topics
What cells recognize, secret or remodel at the biomaterials interface is the provisional extracellular matrix. How it relates to the biocompatibility of materials and how we can control the matrix dynamics from the materials site is the main topic of research in the group.We perform systematic studies in the following directions:
- Spontaneous assembly of ECM proteins at cell-biomaterials interface and their interaction with living cells;
- Electrospinning of nanofibres from natural and synthetic polymers for guided cellular behaviour;
- Cellular interaction with biomimetic hydroxiapatite nanocristals and protein composite coatings;
- Remodelling of ECM proteins at the cell-biomaterials interface.
A novel type of hybrid PLA-Fibrinogen nanofibres developed in our lab. They are deposited as random (a) or aligned (b) shown to induce distinct functional response of endothelial cells acquiring either stelate (c) or elongated (d) morphology, respectively (Gugutkov et al, 2010, in preparation)
Recently we have employed distinct silane chemistry and co-polymer compositions to create model substrates with controlled density of OH, COOH, NH2 and CH3 groups, thus varying their chemical composition, charge and hydrophilic/hydrophobic balance. Combining AFM, SEM and other nanoindentation techniques we examined the early protein adsorption events at the nanoscale, corroborating them with the microscopic response of endothelial cells and fibroblasts. Apart from the paradigm that cellular interaction depends mainly on the adsorption of soluble matrix proteins, we followed the surface behaviour of other important ECM constituents (nonsoluble), such as type IV collagen and laminin-unique multifunctional matrix proteins that play a crucial role in the organization of the basement membrane. In a series of recent communications we have described a novel phenomena – substratum-induced protein assembly – involving the behaviour of fibronectin, fibrinogen, vitronectin, collagen IV and laminin. Furthermore we show that varying with the density of OH groups, one can tailor living cell–protein interaction. In general, proteins can form objects of various shapes and one fascinating possibility is to use them for guiding cellular behaviour. Recently, nanotechnology has made it possible to produce biomimetic nanofibers; using our own device we successfully electrospun nanofibres from various natural and synthetic polymers and employed them in our ongoing research projects: EULANEST (international) and MAT 2009-1440 (national).
AFM images of adsorbed native collagen type IV in hydrophilic (A) and hydrophobic (B) environments. Adsorption concentration of 50 mg/ml for 30 minutes and magnification increasing from left to right (Coelho et al, 2010)
