The distribution of fibronectin in lymph nodes infiltrated by Hodgkin's disease. An immunoperoxidase study on paraffin sections.

The tissue distribution of fibronectin (FN) was examined using a commercial anti-FN serum, the peroxidase-anti-peroxidase (PaP) technique, and paraffin sections of 22 lymph nodes affected by Hodgkin's disease. Vascular basement membranes and reticulin fibres are selectively stained and their structural changes in this pathological condition become readily visible. In contrast to the normal lymph node and to Hodgkin's disease with lymphocytic predominance, cases of mixed cellularity disease contain individual and focally grouped cells displaying intracytoplasmic FN. In nodular sclerosis these cells with fibroblast morphology are consistently numerous in the marginal zones of the cellular nodes. Strongly reacting mastocytes probably absorbed the applied antiserum non-immunologically. All the other cell types giving rise to the varying appearances of Hodgkin's lesions are consistently negative with respect to intracellular FN, including all forms of Hodgkin cells. We conclude that in Hodgkin's disease the immigration of FN-secreting fibroblasts is an integral part of the early sclerosing reaction, which in itself is a defence/repair mechanism closely related to scar formation.