It has been observed that CCL2 chemokine and junctional proteins JAM-A (junctional adhesion molecule A) and ALCAM (activated leukocyte cell adhesion molecule), expressed on the surface of both monocytes and endothelial cells, play a key role in the transmigration of monocytes across the BBB during the acute phase of infection [184,185]. This evidence concerns the gene ALCAM and infection.