Immunohistochemical localization of immunoglobulins in bovine granulomatous lesions

The immunohistochemical distribution of IgG, IgA and IgM in granulomatous lesions caused by Actinomyces bovis, Actinobacillus lignieresi, Actinomyces (Corynebacterium) pyogenes, Pseudomonas aeruginosa, Staphylococcus aureus and Mycobacterium bovis was studied. Numerous IgG-containing cells (plasma cells) were distributed in the peripheral connective tissue layers, but not in the epithelioid cell layer. A few scattered IgA- and IgM-containing cells were found in all the lesions examined. Mycobacterial granulomas contained fewer IgG-cells than did non-mycobacterial granulomas. Eosinophilic club-shaped bodies were found in A. bovis, A. lignieresi, P. aeruginosa and S. aureus, but they were generally negative for IgG, IgA and IgM.