In order to test the efficacy of their new vaccine, a team o…

In order to test the efficacy of their new vaccine, a team of investigators decides to immunize different strains of mice. The graduate student in charge of immunization decides to check the strains available and was informed by the lab animal technician that the vivarium has extra RAG1/2 deficient mice that will be euthanized if not used. The student laughed and responded you can keep your RAG1/2 KO mice because: