Autonomous xenogenic cell fusion of murine and chick skeletal muscle myoblasts

Tomohide Takaya, Yuma Nihashi, Shotaro Kojima, Tamao Ono, Hiroshi Kagami.

Institute for Biomedical Sciences, Shinshu University, Nagano, Japan.

2017 Japan-Thailand International Symposium on Animal Biotechnology (Ina, Japan), 2017/07/05 (Poster).

Abstract

Summary: Cell-cell fusion has been a great technology to generate valuable hybrid cells such as hybridomas. We utilized skeletal muscle myoblasts to establish a novel method for cell fusion. Myoblasts are mononuclear myogenic precursor cells but fuse mutually to form multinuclear myotubes. We found that murine and chick myoblasts spontaneously and interspecifically fuse to form hybrid myotubes in vitro. This is the first evidence for the autonomous xenogenic fusion of mammalian and avian cells.

Materials & Methods: We generated the murine myoblasts expressing GFP (mMB-GFP) and the chick myoblasts expressing DsRed (chMB-DsRed). mMB-GFP and chMB-DsRed were cocultured and induced to differentiate in various condition. Xenogenic myoblast fusion was detected as the GFP⁺/DsRed⁺ myotube, and multinucleation was confirmed by nuclear staining.

Results & Discussion: After 24 h of the coculture of mMB-GFP and chMB-DsRed in differentiation medium, the multinuclear myotubes expressing both GFP and DsRed were observed, indicating that mMBs and chMBs fuse interspecfically. These GFP⁺/DsRed⁺ hybrid myotubes were able to survive and grew to hyper-multinucleated mature form. We also found that undifferentiated mMB-GFP efficiently fuse to the chMB-DsRed-derived myotubes. One of the reasons of asymmetric fusion abilities between mMBs and chMBs might be the difference of amino acid sequences of myomaker, which is an indispensable transmembrane protein for myoblast fusion. Although the molecular mechanism of xenogenic cell fusion is still unclear, myoblast-based fusogenic technique will open up an alternative direction to create novel hybrid products.