Trbc1-P2A-CreERT2-T2A-EGFP Mouse

TRBC1 (T cell receptor beta constant 1) encodes the T cell receptor beta chain constant region 1 and is a component of the αβ T cell receptor (TCR). During αβ T cell development, TCRβ gene rearrangement involves mutually exclusive selection between the two constant regions, Trbc1 and Trbc2. Consequently, the mature T cell population typically includes both TRBC1-positive and TRBC1-negative cells ^[1-2]. Based on this feature, TRBC1 has been widely used for T cell clonality analysis and can be combined with flow cytometry to assess the clonal composition of T cell populations ^[1-2]. In recent years, TRBC1 has also been explored as a molecular target for targeted therapy of T cell malignancies, providing new research directions for T cell-related disease studies and immunotherapy ^[3].

The Trbc1-P2A-CreERT2-T2A-EGFP mouse was constructed using gene editing technology by replacing the endogenous mouse Trbc1 gene stop codon with the "P2A-CreERT2-T2A-EGFP" cassette. In the absence of Tamoxifen treatment, CreERT2 recombinase is primarily localized in the cytoplasm. Upon Tamoxifen induction, CreERT2 recombinase can enter the nucleus and exert its recombination activity. When Trbc1-P2A-CreERT2-T2A-EGFP mice are crossed with mice carrying loxP sites, the offspring, after Tamoxifen induction, are expected to achieve CreERT2 recombinase-mediated sequence recombination between loxP sites in Trbc1-positive cells.