BAFF is up-regulated in central nervous system of neuro-Behçet's disease.

We report that B cell-activating factor of the tumor necrosis factor family (BAFF) is expressed in central nervous system (CNS) of neuro-Behcet's disease (NBD). This study investigated BAFF and BAFF-R (BAFF receptor) in NBD, compared to multiple sclerosis (MS) and to non inflammatory neurological diseases (NIND). Cerebrospinal fluid (CSF) was used to determine the level of BAFF messenger RNA (mRNA) and the level of BAFF-R mRNA in unfractionated cells. A sandwich ELISA was used to quantify soluble BAFF protein levels in serum and in CSF. BAFF and BAFF-R expression in CSF were increased in NBD and MS patients compared to NIND patients. RNA levels of BAFF and BAFF-R were significantly correlated in NBD and MS patients. Serum sBAFF levels were increased in NBD and MS patients, but did not correlate with BAFF expression in CSF. CNS-produced BAFF may support inflammatory cell survival in NBD.