Immunohistochemical observation of lysozyme in macrophages and giant cells in human granulomas.

Lysozyme activity of macrophages and giant cells in various human granulomas were examined with immunoperoxidase bridge method in tissue sections. Various numbers of epithelioid cells and giant cells of epithelioid cell granulomas of tuberculosis, sarcoidosis and Crohn's disease exhibited intense granular cytoplasmic lysozyme activity. Foreign body granulomas induced with various substances showed negative or faintly positive lysozyme stain. Macrophages and giant cells of aspergillus granuloma associated with thymus hypoplasia and T-cell depression contained no lysozyme. The results suggest that cell-mediated immunology plays an important role for the lysozyme synthesis of macrophages in granuloma.