TLR2 and giardiasis: Previous reports indicated that TLR2 involved in the initial recognition of G. duodenalis trophozoites, influenced the production of proinflammatory cytokines IL-6, IL-12 and TNF-α in WT mouse peritoneal macrophages, increased the parasite burden in hosts and aggravated giardiasis when comparing with the TLR2 knockout mice [14].