Bioengineering a miniaturized in vitro 3D myotube contraction monitoring chip to model muscular dystrophies

Quantification of skeletal muscle functional contraction is essential to assess the outcomes of therapeutic pro-cedures for neuromuscular disorders. Muscle three-dimensional "Organ-on-chip" models usually require a sub-stantial amount of biological material, which rarely can be obtained from patient biopsies. Here, we developed a miniaturized 3D myotube culture chip with contraction monitoring capacity at the single cell level. Optimized micropatterned substrate design enabled to obtain high culture yields in tightly controlled microenvironments, with myotubes derived from primary human myoblasts displaying spontaneous contractions. Analysis of nuclear morphology confirmed similar myonuclei structure between obtained myotubes and in vivo myofibers, as compared to 2D monolayers. LMNA-related Congenital Muscular Dystrophy (L-CMD) was modeled with suc-cessful development of diseased 3D myotubes displaying reduced contraction. The miniaturized myotube tech-nology can thus be used to study contraction characteristics and evaluate how diseases affect muscle organization and force generation. Importantly, it requires significantly fewer starting materials than current systems, which should substantially improve drug screening capability.