ICAM1 and bacterial infectious disease: In agreement with and as a complement to these studies, we show here that the absence of pericytes leads to significantly increased leukocyte migration into the CNS during an acute bacterial infection, which is associated with an increased brain expression of the neutrophil chemokines CXCL1 and CXCL2 as well as ICAM-1 (and the monocyte chemoattractant CCL2).