Construction of β2m knockout mice

Abstract:

The β2m (Beta-2-microglobin) gene encodes a non-glycosylated protein that functions as an important component of major histocompatibility complexⅠ(MHCⅠ) for antigen presentation. To evade immune mediated clearance, human tumors and pathogens have adopted different strategies, including loss of MHCⅠexpression. Appropriate animal models are essential for understanding the mechanisms underpinning the clinical treatment of tumor and other human diseases. We constructed β2m knockout mice using CRISPR/Cas9 gene editing tool through embryo microinjection. Subsequently, genotyping and phenotyping of knockout mice were performed by PCR, qPCR, and flow cytometry. Mice genotyping showed that the coding region of the target gene was absent in the knockout mice. Real time PCR showed that mRNA level of β2m was significantly downregulated. Flow cytometry showed that the proportions of CD8+ killer T cells was significantly reduced in a variety of tissues and organs of the immune system. Taken together, we have successfully constructed a strain of β2m knockout mice, which will facilitate subsequent in vivo study on the function and mechanism of the β2m gene.