Interestingly, the infectivity index appeared to increase in the MyD88−/−, TLR2−/−, and TLR4−/− mice during the course of infection compared to infected WT macrophages (Figure 1C), confirming the involvement of TLR2, TLR4, and MyD88 in the recognition of the parasite and defining the fate of L. amazonensis infection. The gene discussed is TLR4; the disease is infection.