ABSTRACT
Background: Transgenesis by microinjection has been widely used for the generation of different mouse models. Different variables of the procedure may critically affect the efficiency of the process. A DNA construction that carries the CXCL2 promoter gene and firefly luciferase has been used to optimize aspects of the procedure. Three different concentrations (0.5, 1.0 and 4.0 ng/µl) of the DNA construction to microinject a total of 1981 zygotes has been tested. Intact/injected embryos, pregnancy and birth rate, survival of pups 7 days after birth, number of transgenic pups and overall transgenic efficiency was registered and analyzed by Z test of proportions for each group. Results: A total of seven transgenic founders were detected for the three DNA concentrations used, 1 in 46 alive pups in the 0.5 ng/µl group, 5 in 38 alive pups in the 1 ng/µl group and 1 in 21 alive pups in the 4 ng/µl group ( p < 0.1). The overall transgenic efficiency was higher for the 1 ng/µl concentration, with a transgenic rate of 13.2%. Conclusions: In conclusion, we have selected the best operative conditions to maximize the transgenesis efficiency. Furthermore, the transgenic lines developed could be used as a reporter model of innate immunity activation with many different applications in the fields of immunology, cancer and neurodegenerative diseases.