Construction of Hepatic-Lobule-Like 3-D Vascular Network in Cellular Structure by Manipulating Magnetic Fibers

Without perfusable vascular networks, 3-D tissues populated with cells cannot maintain a living condition. To construct 3-D tissues, a well-organized vascular network is required. In this article, a method for constructing a hepatic-lobule-like vascular network in a 3-D cellular structure by using magnetic fields is employed. To realize channel networks that mimic the hepatic lobule, steel rods and magnetic fibers were utilized as a sacrificial mold in fibrin gel. The steel rods and fibers were connected by magnetic fields using magnetic tweezers. In our previous work "Construction of hepatic lobule-like vascular network by using magnetic fields" (Int. Conf. Robot. Autom., 2018, pp. 2688-2693), the tweezers were designed by 2-D simulation data. In addition, a 3-D cellular structure without a channel network was only cultured. New tweezers were designed based on 3-D simulation data to generate higher magnetic fields than the former tweezer. In addition, a tissue with the 3-D channel network was cultured for a week. To verify that the channel network can supply the nutrients to the cells in tissues, the viability of the cells located on the structure was analyzed. The cells close to the channel network show a higher cell viability than the cells far from the channel network.