Tissue-Mimicking Geometrical Constraints Stimulate Tissue-Like Constitution and Activity of Mouse Neonatal and Human-Induced Pluripotent Stem Cell-Derived Cardiac Myocytes.

Götz Pilarczyk,Michael Hausmann,Robert Lemor,Alexandra Raulf,Manuel Gunkel,Bernd Fleischmann

doi:10.3390/jfb7010001

Abstract

The present work addresses the question of to what extent a geometrical support acts as a physiological determining template in the setup of artificial cardiac tissue. Surface patterns with alternating concave to convex transitions of cell size dimensions were used to organize and orientate human-induced pluripotent stem cell (hIPSC)-derived cardiac myocytes and mouse neonatal cardiac myocytes. The shape of the cells, as well as the organization of the contractile apparatus recapitulates the anisotropic line pattern geometry being derived from tissue geometry motives. The intracellular organization of the contractile apparatus and the cell coupling via gap junctions of cell assemblies growing in a random or organized pattern were examined. Cell spatial and temporal coordinated excitation and contraction has been compared on plain and patterned substrates. While the α-actinin cytoskeletal organization is comparable to terminally-developed native ventricular tissue, connexin-43 expression does not recapitulate gap junction distribution of heart muscle tissue. However, coordinated contractions could be observed. The results of tissue-like cell ensemble organization open new insights into geometry-dependent cell organization, the cultivation of artificial heart tissue from stem cells and the anisotropy-dependent activity of therapeutic compounds.

Highlights

Current advances in stem cell research provide a cell repertoire that facilitates the artificial reconstitution of multicellular ensembles with properties close to native tissues [1]
In contrast to a non-patterned flat glass substrate, the cells should arrange along these lines, leading to electrical and mechanical coupled pearl chain-like cell ensembles, as schematically shown (Figure 1f)
As well as human-induced pluripotent stem cell (hIPSC)-derived cardiac myocytes were grown on flat glass cover slides and line-patterned PDMS surfaces

Summary

Introduction

Current advances in stem cell research provide a cell repertoire that facilitates the artificial reconstitution of multicellular ensembles with properties close to native tissues [1]. While lineage selection, directed and functional differentiation of pluripotent stem cells are progressively elucidated on a broad basis, the tissue re-organization process is still relatively little developed This may be due to the general problems of controlling cell division and growth in tissue-shaped environments and of inducing appropriate cell to cell interactions, including tissue-like cell connections, in order to establish native intercellular signaling. Regardless of whether being primarily cultured after collection from vendor tissue or expanded in permanent culture lines, is randomly shaped and contacted due to the culture dish environment, cell to cell contacts are random or affected by locally-restricted stimuli Such approaches are useful for tissue engineering in the case that the disorganization of such tissue reconstructs is acceptable, for example artificially-grown tumors in radiation research or pharmaceutical testing. A skin reconstitution organized by such gradients lacks higher-order cell ensemble organization, like paracrine-controlled pigment distribution, thickness regulation by cytokine-controlled cell proliferation and local activity of cell types, like fibroblasts [4,5]

Results

Discussion

Conclusion