IL4 and infection: Similarly, the MFI of Ym1 on CD11c+CD11b+ cells was significantly decreased as was the number of CD11c+CD11b+ cells expressing Ym1 at 30 days post-infection in P. murina infected IL-4−/− neonates (Figure 4K,L), consistent with Ym1 expression being partially driven by IL-4 in response to P. murina.