IL1B and infection: To determine whether decreased IL-1β and TNF-α production during infection may contribute to the impaired protection seen in Clec7a–/– and Card9–/– mice, we infected IL-1 receptor type 1– (IL-1R1–), IL-1β–, and TNF-α–deficient mice and found them to exhibit increased footpad swelling after C. cassiicola infection (Figure 4B).