Coatings for improved cell adhesion

Challenge: Colonization of surfaces with biological cells

The colonization of surfaces with biological cells is important in cell culture technology, but also with regard to the ingrowth of prosthetic implants, the development of cell-based implants, or biological test systems in which, for example, the exchange of substances via the endothelial layer of a blood vessel is to be investigated.

In vivo – which means in the natural surrounding tissue – cells are to be found in a structure, the so-called extracellular matrix, with which they communicate and interact by means of various stimuli. Different characteristics of this cell environment such as mechanical properties, charge distributions or the topography have a direct influence on the cell behavior. Biomaterials that reflect these nature-given properties to a high degree, are the basis for functional, durable and compatible products.

Solution: Strategies for biologization of surfaces

At Fraunhofer IGB, we develop strategies for the biologization of surfaces. We modify biopolymers such as heparin, gelatine and hyaluronic acid so that they bind covalently or adsorptively to plastic or metal surfaces. Subsequently, functionalization with specific cell recognition sequences can take place.

Our expertise: Characterization of cell-material interactions and optimization of surface properties

Primary keratinocytes on nubbed structure. The cell interacts directly with the nubs and is firmly anchored.
Human endothelial cell, grown on a 3D-printable polymer.

Our knowledge of the interactions between cells and materials as well as our expertise in the field of cell cultivation enable us to identify the influence of the chemical composition or various surface structures of the biomaterials on cells. In addition to standardized analytical processes we also develop new methods of analysis to meet your requirements.

Tailored to the intended use of the product, for the cell type that is relevant to the application in question, we can evaluate the following parameters on the biomaterial:

  • Cell morphology
  • Cell adhesion:
    • formation of cell-cell junctions
    • formation of the actin skeleton
  • Cell-matrix interaction:
    • number/character of filopodia
    • cell alignment
  • Cell-differentiation:
    • on the protein level
    • immunohistochemical analyses
    • evidence of released factors (e.g. inflammation mediators)
    • on the RNA level
  • Hemocompatibility:
    • coagulation
    • hemolysis, where applicable complement activation
  • Proliferation capability
  • Cell-vitality
  • Cell-damage:
    • morphological changes
    • membrane disintegrity
  • Cell-specific parameters:
    • enzyme activity

Equipment of surfaces against uncontrolled protein adsorption

Within a few seconds first of all unspecific proteins adsorb on the surface of materials from the surrounding environment. These proteins then modify the degree of adhesion of bacteria and cells.

We can equip surfaces wet-chemically or by means of plasma technology so that the protein adsorption is controlled. As a result we are in a position to control an increase or a decrease of the adsorption as well as the selective adsorption of certain proteins and their orientation relative to the surface.

This, among other things, is of great importance for cell adhesion in tissue engineering.

BioRap – Artificial blood vessel systems

Fraunhofer BioRap – Blood vessels from the inkjet printer (German only)

Reference projects

BioRap

Artificial vascular systems for nutrient delivery in tissue engineering.

 

Duration: 2010 – 2012

ArtiVasc 3D

Artificial vascularized scaffolds for the regeneration of three-dimensional tissues.

 

Duration: November 2011 – October 2013