Establishment of lineage tracing method of mice small intestinal stem cell and application in radiation injury

Objective To establish a lineage tracing method with Lgr5-EGFP-CreERT2/ROSA26-stop-EYFP mouse for observing the role of Lgr5+ intestinal stem cells in the renovation of small intestine tissue, and investigate the effects of radiation on the reconstruction of small intestinal stem cell tissue. Methods Lgr5-EGFP-CreERT2/ROSA26-stop-EYFP mice were identified by genotype analysis. Tamoxifen was used to induce the expression of fluorescent protein in mice. The differentiation of intestinal stem cells induced by Tamoxifen was observed by laser confocal microscopy. Lgr5-EGFP-CreERT2/ROSA26-stop-EYFP mice were irradiated with 60Co γ-rays, and the effects of irradiation on the reconstruction of small intestinal stem cell tissue were examined. Results Double positive mice were obtained by identification of Lgr5 gene (174bp) in DNA extraction from the mice tail with PCR method. In mice treated with single injection of Tamoxifen (100mg/kg), it was observed by laser confocal scanning microscopy that the Lgr5+ intestinal s