An immunocytochemical study of the distribution of lysozyme,a1-antitrypsin and a1-antichymotrypsin in the normal and pathological gall bladder

Summary We have studied the distribution of lysozyme (Ly), a₁-antitrypsin (a₁AT) and a₁-antichymotrypsin (a₁AChy) in the normal, chronically inflamed and neoplastic gall bladder mucosa using the peroxidase-anti-peroxidase (PAP) method. Ly was absent from the normal mucosa but it was found only in areas of glandular metaplasia of true antral type and in crypts of possible early metaplastic nature in cases of chronic cholecystitis. a₁AT and a₁AChy were also found in such metaplastic areas, but their presence was also observed immunohistochemically in areas of essentially normal and in non-metaplastic, chronically inflamed gall bladder mucosa. The possible local production of these substances by gall bladder epithelial cells is discussed. Ly, a₁AT and a₁AChy were also found in various histological types of adenocarcinoma of the gall bladder in varying degrees of frequency and intensity, unrelated to the histological type and invasiveness of the tumour.