Ccr2-P2A-CreERT2 Mouse

The Ccr2 (C-C motif chemokine receptor 2) gene encodes CC chemokine receptor 2, a G protein-coupled receptor, primarily involved in monocyte mobilization, migration, and inflammatory responses. CCR2 can regulate the entry of bone marrow-derived monocytes into peripheral blood by binding chemokines such as CCL2 and CCL7, and promote their recruitment to infected or inflamed tissues. In mice, CCR2 is mainly expressed on Ly6C^hi inflammatory monocytes and is an important molecule regulating monocyte trafficking and innate immune responses. Dysfunction of Ccr2 can affect monocyte tissue infiltration and the inflammatory microenvironment, playing an important role in the development and progression of neuroinflammation, infection, and various inflammatory diseases ^[1-2].

Ccr2-P2A-CreERT2 mice were generated using gene editing technology; the stop codon of the mouse Ccr2 gene was replaced with the "P2A-CreERT2" cassette. In the absence of tamoxifen treatment, CreERT2 recombinase is mainly localized in the cytoplasm; after tamoxifen induction, CreERT2 recombinase can translocate to the nucleus and exert its recombinase activity. When Ccr2-P2A-CreERT2 mice are crossed with mice carrying loxP sites, after tamoxifen induction, the offspring mice are expected to undergo CreERT2 recombinase-mediated sequence recombination between loxP sites in Ccr2-positive cells.