RAG1 and infection: Quantification of RB50 and RB50ΔclpV in respiratory tract organs of Rag1-/- mice on day 21 (prior to death with RB50ΔclpV infection) revealed similar numbers of Bordetella (Fig 2B) indicating that the hypervirulence of the ΔclpV strain is not caused by increased bacterial load in the respiratory tract.