TLR3 and dry eye syndrome: In line with reported qPCR results (19) and our previous immunostaining (34), we found bright TLR3 expression in basal KCs in cryosections and moderate TLR3 levels in primary KCs but not in CD207+ LCs (Fig. 3A and Supplemental Fig. S2A, B), implying that other dsRNA sensors (e.g., PKR, RIG-I, MDA5) may be expressed in LCs.