By contrast, infection in IL-33 KO mice was associated with a significant attraction of B lymphocytes, CD4+ and CD8+ T lymphocytes, as well as NK cells on Day 60 (Fig. 7a–d), without any clear impact on spleen weight, nor on GC area (Fig. 7g, h), yet ensuring parasite control (Fig. 2b). Here, IL33 is linked to infection.