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Room: RS 211
Recently, 3D models of human skeletal muscle (hSKM) tissue have been engineered and shown to be responsive to pharmacological stimulation. One of the central benefits of these in vitro models is their utility in phenotypic drug screens. Candidate treatments for myopathic diseases can be assessed for positive muscle strength effects, while other drugs can be tested for off-target adverse effects on the skeletal muscle. However, current hSKM engineering methods are limited in scale – only two hSKM tissues can be made per mold, and measurement of contraction force is laborious. For an hSKM drug screening platform to be truly viable, it must be able to produce hSKMs in bulk and allow simple quantification of hSKM strength.
Here we report the development of a human skeletal muscle microtissue (hMMT) platform, capable of generating hSKM in bulk. The platform consists of a custom polydimethylsiloxane (PDMS) 96-well plate that holds hMMTs through two micropost anchor points. hMMTs release calcium and contract in response to acetylcholine, deflecting the microposts measurably. Furthermore, we have automated measurement of this post-deflection using a custom Matlab program. Through western blotting and confocal image analysis, we demonstrate a time-dependent increase in myofiber size and in the maturation marker myosin heavy chain over 14 days of tissue culture. As hypothesized, hMMT drug response is indicative of clinical drug effect. Dexamethasone and cerivastatin – known to be myopathic in humans – reduced hMMT strength. Similarly, human insulin-like growth factor increased hMMT strength, as seen in in vivo animal studies.