Immunological function of the blood-cerebrospinal fluid barrier.
Because the brain lacks a true lymphatic system, it is unclear how peripheral lymphocytes recognize foreign antigens present in the central nervous system. This report demonstrates that the choroid plexus, which constitutes the blood-cerebrospinal fluid barrier, is able to present foreign antigen to, and stimulate the proliferation of, peripheral helper T lymphocytes through an Ia-dependent, major histocompatibility complex-restricted mechanism. Furthermore, in vivo, choroid plexus epithelial cells have access to, and are capable of taking up, virus-sized particles injected elsewhere into the cerebrospinal fluid. Thus these data suggest that the blood-cerebrospinal fluid barrier may play a role in immunological communication between the central nervous system and periphery, a function relevant to the initiation of immunological responses to central nervous system infections and autoimmune processes and for the surveillance of tumor cells in the cerebrospinal fluid.
Nathanson
J A
JA
Department of Neurology, Harvard Medical School, Massachusetts General Hospital, Boston 02114.
Chun
L L
LL
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D001769:Blood; D002478:Cells, Cultured; D002555:Cerebrospinal Fluid / Q000276:immunology*; D002831:Choroid Plexus / Q000276:immunology*; D004261:DNA Replication; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000276:immunology