IFrag-/- but not RAG-/- mice develop rapidly progressing bone marrow failure in response to PC lung infection. Changes contributing to accelerated bone marrow cell apoptosis in IFrag-/- mice appear to be initiated around day 7 post infection. To gain further insight into the mechanism underlying the induction of bone marrow failure in IFRag-/- but not RAG-/- mice in response to PC lung infection, IFRag and RAG mice were PC infected via intra-tracheal inocculation of 10e7 nuclei and bone marrow responses were assessed at day 0, and 7 post infection. One group of IFRag-/- mice also received anti-oxidants treatment with N-Acetyl cysteine in drinking water (100mg/ml) throughout the course of infection (IFRag-/- +NAC) as oxidative stress appeared to be a contributing factor. Overall design: RT2 profiler PCR array, 5 conditions, 3 biological replicates