Higuera - In vivo screening of extracellular matrix components produced under multiple experimental conditions implanted in one animal†

Gustavo A. Higuera,z*b Jeanine A. A. Hendriks,zc Joost van Dalum,a Ling Wu,a
Roka Schotel, Liliana Moreira-Teixeira, Mirella van den Doel, Jeroen C. H. Leijten, Jens Riesle, Marcel Karperien, Clemens A. van Blitterswijk and Lorenzo Moroni

Integrative Biology 2013

Abstract

Animal experiments help to progress and ensure safety of an increasing number of novel therapies,
drug development and chemicals. Unfortunately, these also lead to major ethical concerns, costs and
limited experimental capacity. We foresee a coercion of all these issues by implantation of well systems
directly into vertebrate animals. Here, we used rapid prototyping to create wells with biomaterials to
create a three-dimensional (3D) well-system that can be used in vitro and in vivo. First, the well sizes
and numbers were adjusted for 3D cell culture and in vitro screening of molecules. Then, the
functionality of the wells was evaluated in vivo under 36 conditions for tissue regeneration involving
human mesenchymal stem cells (hMSCs) and bovine primary chondrocytes (bPCs) screened in one
animal. Each biocompatible well was controlled to contain ml-size volumes of tissue, which led to tissue
penetration from the host and tissue formation under implanted conditions. We quantified both
physically and biologically the amounts of extracellular matrix (ECM) components found in each well.
Using this new concept the co-culture of hMSCs and bPCs was identified as a positive hit for cartilage
tissue repair, which was a comparable result using conventional methods. The in vivo screening of
candidate conditions opens an entirely new range of experimental possibilities, which significantly
abates experimental animal use and increases the pace of discovery of medical treatments.