Experimental Animal Division

A novel hairless mouse strain for in vivo imaging

C57BL/6J-Hr<em1Utr> (RBRC10096)

Courtesy of Fumihiro Sugiyama, Ph.D.

An adult Hr^{em1Utr/em1Utr} mouse, which shows the sagging skin and heritable hairless phenotype.

In vivo imaging for the living mice is one of the remarkable analysis because it allows the monitoring of biomolecules directly and non-invasively. Mouse hair is known to block, absorb and scatter lights independent of hair-colors. Therefore, before this analysis, we must remove mouse hair by shaving with a razor, depilatory cream, etc. To remove this time-consuming and troublesome treatment, depositor (Dr. Sugiyama) and his colleague generated Hr^{em1Utr/em1Utr} mouse strain containing Hr gene mutations by CRISPR/Cas9 system [1]. Hr gene is related with hair-cycle control and other hairless strains [2] also have Hr gene mutations. Actually, it was reported that Hr^{em1Utr/em1Utr} adult mice showed completely hairless and enabled In vivo imaging for both indocyanine-green (ICG: an excitation maximum of 800 nm and an emission maximum of 840 nm) and near-infrared fluorescent protein (iRFP: an excitation maximum of 690 nm and an emission maximum of 713 nm).