The predominant cause of meningitis in older infants and children is Streptococcus pneumoniae, which interacts with the endothelial receptors polymeric immunoglobulin receptor (pIgR) and platelet endothelial cell adhesion molecule-1 (PECAM-1 or CD31) to invade the CNS (12). Here, PECAM1 is linked to infectious meningitis.