As expected [15], IL-4Rα−/lox–treated mice were unable to clear infection, and CD4+ T cells were also essential for clearance in SM-MHCCreIL-4Rα−/lox mice, as depletion resulted in increased adult worm burdens in SM-MHCCreIL-4Rα−/lox mice (Figure 5). This evidence concerns the gene CD4 and infection.