WP05 – Biocompatibility and biofunctionality screening

Objectives

The overall objective of WP05 is to develop an in vivo biocompatibility and biofunctionality screening for validation of the constructs that passed in vitro assessment in WP03. This will enable selection of the best constructs for testing in the orthotopic animal models within WP6 (mini pigs, horses). We will select the biocompatible implants based in their capacity to sustain human chondrocyte growth (chondroconduction) for cell-based therapy approaches. The capacity to induce chondrogenic differentiation (chondroinduction) for cell-free implantation strategies will be tested as well.  The chondrogenic capacity of the different scaffolds will be evaluated through ectopically implantation in nude mice. Additionally, the scaffold will be placed in an osteochondral porcine tissue with a chondral defect, the construction will be implanted in the nude mice to generate a osteochondral environment allowing us to evaluate integration capacity and regeneration potential.

Interactions of WP05 with other WPs
Fig. 1: Interactions of WP05 with other WPs

Workpackage Description

For the accomplishment of WP05 we will isolate human chondrocytes and bone marrow-derived mesenchymal cells (BMSCs) for further testing of their chondrogenic potential when combined with different materials using a model of ectopic implantation (non physiological location of the implant) in vivo.
Chondrocytes will be obtained from healthy areas of femoral condyle patients receiving total knee replacement surgery. BMSCs will be isolated from marrow aspirates of healthy donors.

 

Microscopic view of human chondrocytes and BMSCs

Human cells will be loaded into different biomaterials using moulds. Once assembled the constructions will be implanted subcutaneously in the back of nude mice (immunologically deficient animals) and maintained up to six weeks. The capacity of maintain or induce a chondrocytic phenotype will be assayed, in a second round including specific growth factors with known chondrogenic potential.

Finally, selected biomaterials will be tested ectopically into a chondral environment by embedding assembled constructs into porcine osteochondral tissue samples and implanting the tissue samples ectopically in nude mice. Using biomechanical, molecular and histological techniques we will determine chondrogenic repair  and integration capacity of the different materials.

 

WP Leader

University of Navarra

Dr. Felipe Prσsper