Figure 1

Organisation of the follicular and MZ B-cell compartments in the human spleen. (A) Schematic representation of the various T- and B-cell areas in the human spleen. PALS: periarteriolar lymphatic sheath (T-cell zone). (B) Staining of paraffin-embedded sections of human spleen with CD20 mAb revealed B-cell follicles (BZ) and a ring of B-cells separating the T-cell zone (TZ) from the red pulp (RP) (original magnification x10). (C) Sections of human spleen were simultaneously stained with PAX5, CD3 and ASM (alpha smooth muscle actin) mAbs. The network of fibroblast-like cells stained with the anti-ASM mAb (blue) subdivides the outer (OMZ) from the inner marginal zone around B-cell follicles (PAX5+, green) and separates the T-cell zone (CD3+, red) from the RP (left panels) (original magnification x10). In the upper left panel, a germinal centre (GC) is visible within the B-cell follicle. General tissue organisation is shown by DAPI staining of nuclei (right panels).