Ultrastructural localization of adhesion molecules in the healthy

Abstract

The functional expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and MAdCAM-1 in the choroid plexus is indicative of a role of this structure in the communication of the immune system with the central nervous system (CNS). In order to gain further insight into the possible functions of adhesion molecules expressed in the choroid plexus, we investigated the exact ultrastructural localization of VCAM-1, ICAM-1 and MAdCAM-1 on semithin and ultrathin cryosections of the choroid plexus of healthy mice and of mice suffering from experimental autoimmune encephalomyelitis (EAE). In the healthy choroid plexus VCAM-1 and ICAM-1, but not MAdCAM-1, could be detected on the apical surface of the choroid plexus epithelial cells. During EAE, immunoreactivity for VCAM-1 and ICAM-1 was dramatically increased. Additionally, apical expression of MAdCAM-1 was observed on individual choroid plexus epithelial cells during EAE. At the same time, VCAM-1, ICAM-1 or MAdCAM-1 were never present on the endothelial cells of the fenestrated capillaries within the choroid plexus. The polar expression of VCAM-1, ICAM-1 and MAdCAM-1 on the apical surface of choroid plexus epithelial cells, which form the blood-cerebrospinal fluid barrier, implies a previously unappreciated function of this barrier in the immunosurveillance of the CNS.

Human cerebrospinal fluid central memory CD4+T cells: Evidence for trafficking through choroid plexus and meninges via P-selectin

“…ICAM-1 was constitutively expressed in the choroid plexus of healthy mice and mediated binding of lymphocytes in vitro with a StamperWoodroof assay (34,35). In contrast to previous studies in rodents (34,36), we did not detect VCAM-1 in choroid plexus endothelium or epithelium. Although the reason for this difference remains speculative, it may be related to the sensitivity of the techniques in perfused animal tissue versus human autopsy tissue, or to species-related variation.…”

Molecular anatomy and functions of the choroidal blood-cerebrospinal fluid barrier in health and disease

“…No gold particles are detected in sections incubated with isotype control antibody. For details see [167] ▸ allowing them to resist the shear forces exerted by the CSF flow. In addition, apical ICAM-1 and VCAM-1 may be the source for soluble ICAM-1 and VCAM-1 found in increased concentrations in the CSF of patients with multiple sclerosis, viral encephalitis or bacterial meningitis [118,125].…”

The central nervous system is a target of acute graft versus host disease in mice

“…However, absolute numbers revealed equivalent parenchymal infiltration in all of these sites ( Figure 1M), consistent with models of infection, ischemias, and autoinflammatory diseases. 22,25 Histopathological analysis of brain sections revealed evidence of meningoencephalitis, choroiditis, and myelitis with moderate or marked lymphocytic infiltration on day 21 after allo-HSCT (Figure 2A). Restricted to recipients of allo-HSCT, we observed significant apoptosis in neurons and neuroglia ( Figure 2B).…”