An easy-to-use and versatile method for building cell-laden microfibres

Jérome Kalisky,Jean-Christophe Fricain,Murielle Rémy,Robin Siadous,Claire Rigothier,Reine Bareille,Joëlle Amedée-Vilamitjana,Hugo Oliveira,Jérémie Raso,Raphaël Devillard

doi:10.1038/srep33328

Abstract

Fibre-shaped materials are useful for creating different functional three-dimensional (3D) structures that could mimic complex tissues. Several methods (e.g. extrusion, laminar flow or electrospinning) have been proposed for building hydrogel microfibres, with distinctive cell types and with different degrees of complexity. However, these methods require numerous protocol adaptations in order to achieve fibre fabricating and lack the ability to control microfibre alignment. Here, we present a simple method for the production of microfibers, based on a core shell approach, composed of calcium alginate and type I collagen. The process presented here allows the removal of the calcium alginate shell, after only 24 hours of culture, leading to stable and reproducible fibre shaped cellular constructs. With time of culture cells show to distribute preferentially to the surface of the fibre and display a uniform cellular orientation. Moreover, when cultured inside the fibres, murine bone marrow mesenchymal stem cells show the capacity to differentiate towards the osteoblastic lineage, under non-osteoinductive culture conditions. This work establishes a novel method for cellular fibre fabrication that due to its inherent simplicity can be easily upscaled and applied to other cell types.

Highlights

Many in vivo tissues are composed of microscale alignments of cells, associated or not with extracellular matrix (ECM) elements
This fabrication approach consists on three steps; the first one concerns the preparation of the calcium alginate shell (Fig. 1A)
The third step consists on the removal of the calcium alginate shell, after 24 hours of culture, leading to a stable and reproducible fibre shaped cellular construct (Fig. 1C and Supplementary Figure S1)

Summary

Introduction

Many in vivo tissues are composed of microscale alignments of cells, associated or not with extracellular matrix (ECM) elements (e.g. microcapillaries, nerve network and muscle fibres). Collagen fibres have shown to support myocyte, neural cells or endothelial cell morphology and function[6] In this sense, heterogenous core-shell fibres have emerged, where cells were incorporated in a core collagen fiber inside a calcium alginate outer shell[13]. We present a new ready-to-use method for the production of microfibers, using a core shell approach, composed of calcium alginate shell and a cellularized type I collagen core This process doesn’t require specific devices or a high cell density. Another added value to this new approach concerns the easy removal of the calcium alginate hydrogel, without enzymatic degradation, after only 24 hrs of culture, and while preventing fibre aggregation up to two weeks of culture. This approach enables an easy adaptation to novel shape design, while allowing a tight control over fibre reproducibility

Methods

Results

Conclusion