Aktuelle Neurologie 2006; 33 - P375
DOI: 10.1055/s-2006-953200

Accumulation of class switched IgD-IgM- memory B cells in the cerebrospinal fluid during neuroinflammation

S. Cepok 1, G. Von Geldern 1, V. Grummel 1, S. Hochgesand 1, H. Celik 1, H.P. Hartung 1, B. Hemmer 1
  • 1Düsseldorf

Inflammatory diseases of the central nervous system (CNS) are characterized by cerebrospinal fluid (CSF) pleocytosis often involving the recruitment of B cells. Little is known about the phenotype of B cells that are present in the CSF during neuroinflammation. To address the phenotype of these B cells, we studied the distribution of the major B cell subsets in peripheral blood (PB) and CSF of 25 patients with inflammatory diseases of the nervous system by flow cytometry. Six different B cell subsets were identified in PB and CSF according to the surface expression of IgM, IgD, CD27 and CD19. In all patients analysed, memory B cells outnumbered naïve B cells in the CSF, whereas naïve B cells were more prevalent in PB. The accumulation of memory B cells in the CSF was largely due to the recruitment of IgM-IgD- class switched memory B cells. The distribution of IgM+IgD+, IgM-IgD+, IgM+IgD- memory cells and immature cells did not differ significantly between CSF and PB. These findings demonstrate a selective recruitment of IgM-IgD-memory B cells to the CSF suggesting a specific role of these cells during neuroinflammation.