IL4 and infection: However, IL-4-treated C3H/He macrophages showed lower infection rate, lower amount of amastigotes per cell, and lower total parasite load 96h after infection compared to IL-4-treated BALB/c macrophages (Fig 1D–1F), showing that, even under anti-inflammatory stimulus, the C3H/He macrophages remained more resistant to infection than BALB/c.