Cell coupling system for somatic cell cloning using microfluidic chip

Abstract

We have proposed cell coupling system for mammalian somatic cell cloning process in microfluidic chips. There are two kinds of nuclear transfer methods, microinjection and cell fusion; we selected the cell fusion method. Unlike the conventional method by the manual labor under the microscope, our aim is developing automated cloning work which is being performed in microfluidic chip. Although this method has some sub-process, here, we focused on in-chip cell coupling process. The coupling is to contact and fix cells before impressing the voltage in electric fusion. Instead of conventional manual operation using small glass pipette, the same process was built in a microfluidic chip with a new protocol. The novel protocol takes three steps; (1) an oocyte supplied into micro chip is captured in narrow a micro channel, (2) a donor cell is fused with the immobilized oocyte by dielectrophoresis, and then the new oocyte and donor cell couple are released. For coupling process, we use two kinds of cells, which are bovine oocyte (100~150 ¿m) and bovine fibroblast (10~30 ¿m) as donor cell. In order to achieve these steps, we designed a microfluidic chip in which fluid force and dielectrophoresis force are applied. And we demonstrated simulations and experiments about fluid and electric field analysis. In this paper, we also presented the cell coupling sequence in a microfluidic chip, total system setup and the result of semi-manual experiments in the chip for future automatic cell coupling.