TLR9 and systemic lupus erythematosus: However, TLR7 and TLR9 were recently shown to have distinct effects in a murine model of Lupus [41] and also during experimental West Nile Encephalitis, where Tlr7-/- mice, but not Tlr9-/- mice, showed an impaired CD45+ leukocyte and macrophage infiltration at the site of infection [24].