Infection with R001 resulted in reduced, uneven staining of the membrane and diffuse staining of the cytoplasm, indicating dissociation of occludin from the cell membrane, possibly by an MMP-8-mediated cleavage, as observed by Schubert-Unkmeir et al. [41] for meningococcal infections of human brain microvascular endothelial cell monolayers. Here, OCLN is linked to meningococcal infection.