IL4R and infection: To determine whether IL-4Rα signaling on keratinocytes at the site of infection contributes to nonhealing disease during CL, KRT14cre IL-4Rα−/lox BALB/c mice and appropriate controls (IL-4Rα−/lox BALB/c, IL-4Rα−/− BALB/c, and C57BL/6 mice) were infected s.c. in the left hind footpad with stationary-phase promastigotes, either with 2 × 105 of the highly virulent L. major IL-81 strain (Fig. 2A) or with a dose of 2 × 106 of the less virulent L. major LV39 strain (Fig. 2B).