Abstract: Objective To identify High affinity ligand MULT1-transgenic mice, analyze its elementary phenotype, and perform primary functional study in MULT1. Methods We identified the genotype of transgenic mice by genomic DNA PCR and detected transcripts level of MULT1 in tails by real-time PCR. The flowcytometry and immunohistochemistry were used to analyze the expression of MULT1 in various tissues. Results 25 3'S-strain and 13 4'S-strain MULT1-transgenic mice were obtained and they contain higher MULT1 transcripts. MULT1 protein is mainly expressed on intestinal intraepithelial lymphocytes (iIELs) and thymocytes but not on splenocytes. Moreover, the levels of MULT1 expression on (iIELs) and thymocytes are associated with age. Within iIELs, the percentage of CD8+T cells decreased, while CD4+CD25+Treg cells increased, when compared with wild-type mouse. Conclusion We successfully produced MULT1-transgenic mice. MULT1 is possibly associated with thymic development and aging, as well as immunoregulation in mice.

Key words: transgene, NKG2D ligands, MULT1, genotype, phenotype