RAG1 and infection: While we used the spleen as a representative systemic organ for immune response analysis to RB50 or RB50ΔclpV infection in Rag1-/- mice (Fig 3C), it will be interesting to determine whether a different immune response in the liver contributes to the higher proportion of surviving intracellular B. bronchiseptica during infection (Fig 6F and 6H).