The growing spectrum of tools and approaches available in mice combined with approaches for evaluating the impact of the microbiota (McCoy et al., 2019; Kwon and Seong, 2021) could lead to observations that apply broadly to the range of human and animal pathogens that possess transferrin and lactoferrin receptors, including the most effective strategies for inducing an immune response for prevention of infection. The gene discussed is TF; the disease is infection.