In vivo, the treatment with TLR2 agonist controls parasite replication in target organs through a mechanism dependent on improvement of CD8+ T cells (Bandyopadhyay et al., 2015) and the Th1 response (Chowdhury et al., 2015a) and suppression of CD4+ Foxp3+ T cell function (Chowdhury et al., 2015b), suggesting that the role of TLR2 during infection is an interesting alternative for restraining parasites from spreading to tissues. The gene discussed is CD4; the disease is infection.