Three‐dimensional reconstitution of embryonic cardiomyocytes in a collagen matrix: a new heart muscle model system

TLDR

This approach, simpler and faster than generating transgenic animals, should allow functional consequences of genetic or pharmacological manipulation of cardiomyocytes in vitro to be studied under highly controlled conditions. The study aimed to establish a test bed for genetic manipulation by infecting the collagen‑matrix cardiac myocyte constructs with a recombinant β‑galactosidase‑carrying adenovirus. Cardiac myocytes were embedded in a collagen gel between Velcro‑coated tubes, forming spontaneously beating matrices that could be attached to a force‑measuring system. The resulting 3‑D cardiac myocyte matrices exhibited organized sarcomeric structure, stable contractile force that increased with frequency, length, and calcium, and transduction efficiency up to 50 %, demonstrating physiological behavior superior to monolayer cultures. Published in FASEB Journal, 1997, 11:683–694.

Abstract

A method has been developed for culturing cardiac myocytes in a collagen matrix to produce a coherently contracting 3-dimensional model heart tissue that allows direct measurement of isometric contractile force. Embryonic chick cardiomyocytes were mixed with collagen solution and allowed to gel between two Velcro-coated glass tubes. During culture, the cardiomyocytes formed spontaneously beating cardiac myocyte-populated matrices (CMPMs) anchored at opposite ends to the Velcro-covered tubes through which they could be attached to a force measuring system. Immunohistochemistry and electron microscopy revealed a highly organized tissue-like structure of α-actin and α-tropomyosin-positive cardiac myocytes exhibiting typical cross-striation, sarcomeric myofilaments, intercalated discs, desmosomes, and tight junctions. Force measurements of paced or unpaced CMPMs were performed in organ baths after 6–11 days of cultivation and were stable for up to 24 h. Force increased with frequency between 0.8 and 2.0 Hz (positive "staircase"), increasing rest length (Starling mechanism), and increasing extracellular calcium. The utility of this system as a test bed for genetic manipulation was demonstrated by infecting the CMPMs with a recombinant β-galactosidase-carrying adenovirus. Transduction efficiency increased from about 5% (MOI 0.1) to about 50% (MOI 100). CMPMs display more physiological characteristics of intact heart tissue than monolayer cultures. This approach, simpler and faster than generation of transgenic animals, should allow functional consequences of genetic or pharmacological manipulation of cardiomyocytes in vitro to be studied under highly controlled conditions.—Eschenhagen, T., Fink, C., Remmers, U., Scholz, H., Wattchow, J., Weil, J., Zimmermann, W., Dohmen, H. H., Schäfer, H., Bishopric, N., Wakatsuki, T., Elson, E. L. Three-dimensional reconstitution of embryonic cardiomyocytes in a collagen matrix: a new heart muscle model system. FASEB J. 11, 683–694 (1997)