IFNGR1 and infection: The frequency of blue cells for the different MOIs was not significantly different between C57BL/6 and TNFRp55−/− or IFN-γR−/− splenocytes (Figure S4) suggesting that splenocytes of wildtype, TNFRp55−/− and IFN-γR−/− mice upon infection with Ye display a comparable frequency of Yop injection.