Lymph node (human)

Stain: Silver stain (Gomori). Due to the argyrophilia of reticular fibres the reticular network is black-stained among others such as collagen type I, III, IV. From the fibrous capsule (1) a meshwork of fine reticular fibres penetrates into the cortex of a lymph node crossing the subcapsular (or marginal) sinus (2). At the left a secondary lymphatic nodule (or follicle) is shown with centrally a germinal centre (3) with capillaries (-->). This (secondary) germinal centre is surrounded by a dense cap or mantle zone (4) of B lymphocytes. Note that the reticular fibers are nearly absent in the germinal centre. (5) area of intermediate sinus (or paratrabecular sinus) stuffed with lymphocytes. (Blue arrows) indicate small arterioles/arteries with black-stained basement membranes and adventitial tissue.