(310a) Chimeric Receptor Engineering to Control Cell Fate and Its Applications

When cells respond to changes in an extracellular milieu, membrane proteins expressed on the plasma membrane play a pivotal role as an interface between extracellular and intracellular milieus. If we could engineer membrane proteins, we could artificially regulate various cellular responses [1, 2]. Therefore, we have focused on cytokine receptors that are one of the membrane proteins involved in cell-fate signal transduction, and developed novel artificial receptors that enable signal transduction in response to a ligand quite different from original cytokines. In order to regulate various cellular responses with distinct ligands, an antigen-antibody system, having infinite combinations, was utilized as the ligand and its binding domain.

Until now, we have designed single-chain Fv (scFv)/cytokine receptor chimeras having different kinds of signaling domains, thereby regulating growth [3], migration [4] and death [5] of various mammalian cells including primary cells in response to a specific antigen. In addition, we also developed an antibody selection system based on growth induction of mammalian cells. In this system, a scFv library/growth-inducing receptor chimera is expressed in cells, and the cells expressing antigen-specific scFv can be easily selected based on the growth advantage in the presence of antigen. This panning-less, one-step selection system allowed us to select specific scFvs against not only extracellularly added antigen but also intracellularly expressed antigen. Our chimeric receptor approach, which provides cell-fate controlling and screening platforms, could be useful for regenerative medicine and antibody therapeutics.

References

[1]    Kawahara, M., Ueda, H., and Nagamune, T. "Engineering cytokine receptors to control cellular functions." Biochem. Eng. J., 2010, 48, 283–294.

[2]    Kawahara, M., and Nagamune, T. "Engineering of mammalian cell membrane proteins." Curr. Opin. Chem. Eng. 2012, 1, 411-417.

[3]    Kawahara, M., Chen, J., Sogo, T., Teng, J., Otsu, M., Onodera, M., Nakauchi, H., Ueda, H. and Nagamune, T. "Growth promotion of genetically modified hematopoietic progenitors using an antibody/c-Mpl chimera." Cytokine, 2011, 55, 402-408.

[4]    Kawahara, M., Shimo, Y., Sogo, T., Hitomi, A., Ueda, H. and Nagamune, T. "Antigen-mediated migration of murine pro-B Ba/F3 cells via an antibody/receptor chimera." J. Biotechnol., 2008, 133, 154-161.

[5]    Tone, Y., Kawahara, M., Kawaguchi, D., Ueda, H., and Nagamune, T. "Death signalobody: Inducing conditional cell death in response to a specific antigen." Hum. Gene Ther. Methods, 2013, doi: 10.1089/hgtb.2012.147.