Michael Gelinsky

Scaffold based tissue engineering

Previous and current research

The interdisciplinary group is working on the development of new biomaterials for regenerative therapies and tissue engineering of hard and soft tissues. We are applying biomimetic synthesis principles and want to mimic extracellular matrixes (ECM) of natural tissues with our artificial materials. For example, we have developed several types of scaffolds, made of artificially mineralised collagen fibrils, mimicking the ECM of healthy bone tissue.
In our own cell culture and biochemical labs we are investigating the material cell interactions, material resorption and remodelling and formation of tissues in vitro. The main topics of our actual work can be described as follows:

Development of new biomaterials

We are working on biodegradable materials like calcium phosphate bone cements, porous 3D scaffolds based on biopolymers (like collagen, alginate and hyaluronic acid) or membranes for the use as skin replacement materials. We have developed nanocomposite materials made of collagen and hydroxyapatite (the mineral phase of bone), mimicking ECM of bone – and biphasic, but monolithic biomaterials for the therapy of osteochondral defects. Other projects deal with scaffolds with anisotropic pore systems which can act as guiding structures for outgrowth of axons (peripheral nerve regeneration). In addition, we are interested in utilising special technologies like electrostatic flocking for development of new types of scaffolds – and we are investigating functionalisation of biomaterials with growth factors or other chemokines, encapsulated in micro- or nanocontainers, and release kinetics thereof.

Scaffolds based tissue engineering of hard and soft tissues

After basic biocompatibility tests of the new materials we are studying short and long term performance of the scaffolds in cell culture experiments under static as well as dynamic conditions. For this, the scaffolds are seeded with cells coming from the tissue of interest (bone, cartilage, skin etc.) or with human stem cells. We are analysing cell adhesion, proliferation and differentiation and synthesis of typical markers and ECM components, using modern biochemical and molecular genetic methods. In addition, we are interested in the effects of mechanical stimulation on tissue engineered constructs.

Establishment of in vitro models for bone biomineralisation and remodelling

Formation of nanoscopical hydroxyapatite (calcium phosphate) crystals in the collagen matrix of mineralising bone tissue is controlled by several non-collagenous proteins and other factors, produced by osteoblasts. With in vitro models without and also with cells we are studying the effects of selected proteins and model substances on mineral formation, applying methods like Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) – and try to transfer the insights to better strategies for biomaterials synthesis. By co-cultivating osteoblasts (bone forming) and osteoclasts (bone resorbing cells; figure) on artificial extracellular matrices made of mineralised collagen we are establishing an in vitro model for the complex processes of bone remodelling.

Future prospects and goals

We want to continue our work described above, but also extend new topics like vascularisation of cell matrix constructs and investigation of health risks of synthetic nanoparticles.

TEM micrograph of an osteoclast-like cell, derived from human monocytes, resorbing an artificial scaffold made of mineralised collagen (image: A. Springer)

About

Selected publications

Bernhardt, A., Lode, A., Boxberger, S., Pompe, W., Gelinsky, M. (2007): Mineralised collagen – an artificial, extracellular bone matrix – improves osteogenic differentiation of mesenchymal stem cells. J. Mater. Sci. Mater. Med. (in press; DOI 10.1007/s10856-006-0059-0)

Dittrich, R., Despang, F., Bernhardt, A., Hanke, Th., Tomandl, G., Pompe, W., Gelinsky, M. (2007): Scaffolds for hard tissue engineering by ionotropic gelation of alginate – influence of selected preparation parameters. J. Am. Ceram. Soc. 90: 1703-1708.

Lode, A., Wolf-Brandstetter, C., Reinstorf, A., Bernhardt, A., König, U., Pompe, W., Gelinsky, M. (2007): Calcium phosphate bone cements, functionalized with VEGF: release kinetics and biological activity. J. Biomed. Mater. Res. A 81A: 474-483.

Domaschke, H., Gelinsky, M., Burmeister, B., Fleig, R., Hanke, Th., Reinstorf, A., Pompe, W., Rösen-Wolff A. (2006): In vitro ossification and remodeling of mineralized collagen I scaffolds. Tissue Engineering 12: 949-958.

Yokoyama, A., Gelinsky, M., Kawasaki, T., Kohgo, T., König, U., Pompe, W., Watari, F. (2005): Biomimetic porous scaffolds with high elasticity made from mineralised collagen – an animal study. J. Biomed. Mater. Res. B: Appl. Biomater. 75B: 464-472.

Home page