TLR4 and infection: In a study carried out with I. ricinus cells (IRE/CTVM20), it was shown that the expression of a Toll gene (homologous to the Toll ISCW022740 of I. scapularis) is upregulated after 72 and 120 h of infection with flaviviruses [tick-borne encephalitis virus (TBEV) and louping ill virus (LIV)] but remained unmodulated in response to A. phagocytophilum (54).