Microfluidic in vitro culture system mimicking peristaltic stimulation in bovine embryos

Abstract

This work demonstrates a novel microfluidic $\It{in vitro}$ cultivation system for embryos that improves their development using a partially constricted channel that mimics peristaltic muscle contraction (the gravity-driven stimulation system). To investigate the compressive effects of constriction geometry on embryonic development, different constriction widths of the channel were designed. Bovine embryos were loaded on the channel and the whole system was incubated on a tilting machine to provide embryo movement via gravity. The fertilized embryos were cultivated on the gravity-driven stimulation system until the blastocyst, hatching, or hatched blastocyst stages. The proportion of eight-cell development among total embryos in the constricted channel ($56.77\plusmn13.7%; mean\plusmnSD$) was superior to that in the straight channel ($23.97\plusmn11.0%$). Moreover, the membrane based mechanical stimulation was also designed because of needs for independent control of flow and compressive force (the pressure-driven stimulation system). Therefore, the possibility to improve developmental ratio for bovine embryos was suggested as supporting more precise$\It{in vivo}$ like environment.