To further elucidate the role of AAMs during a chronic S. mansoni infection and to explore the role of IL-4Rα-expressing macrophages in the initiation and regulation of fibrosis, we infected IL-4Rαflox/ΔLysMCre mice and IL-4Rαflox/Δ littermate control mice with 35 cercariae, a dose that in wild-type mice leads to substantial disease and liver fibrosis but low mortality through the chronic phase of infection [10]. Here, IL4R is linked to infection.