Testing the capacity of humanized immune system mice to induce a protective antibody response against the Lyme disease pathogen

In this study, we assessed the ability of mice with humanized immune systems to develop protective antibodies against the bacterial agent of Lyme disease (LD), Borreliella burgdorferi. In contrast to an intact mouse immune system of classical LD models, the humanized immune system could not prevent vaccinated mice from being infected with LD spirochetes. The findings demonstrate that two tested humanized models cannot be used for preclinically testing LD vaccine candidates. Given the results, we hope that the animal-to-human translatability limitations of existing LD mouse models will be more favorably taken as there is no better alternative preclinical model developed.