Lysozyme Content of Granulation Tissue.

The highest lysozyme concentrations in the mammalian body occur in tears and in the mucosa of the antrum, pllorus, and duodenu1n. The origin of these high local concentrations presumably is epithelium, i.e., the tear glands and as yet undetermined cell types in the gastrointestinal mucosa. In contrast, the Iysozyme titer in mesodermal tissue is low; for example, serum averages 1 unit/ccl, and human leucocytes (from the buffy coat of normal blood) contain only 1.8 units per 5,000,000 cells2 However, human cartilage averages about 40 units/g, although this value is without doubt too low because of the difficulty in extracting this tissue. Normal human skin (including a considerable quantity of fibrous tissue) was found to have less than 1 unit/g. The finding of high lysozyme titres in granulation tissue was)therefore unexpected. The lysozyme assays on granulation tissue of man and dog are shown in the accompanying table. As a result of these observations it is now apparent that high lysozyme concentrations are associated with some mesodermal cell types as well as with epithelium. Therefore, further study is warranted with regard to the role of this tissue in the production of lysozyme in ulcerative alimentary disease. The deleterious effect of egg white lysozyme on the gastrointestinal mucosa has been confirmed in our own as well as other laboratories. Furthermore, high stool titres in the absence of occult blood in the feces and with sigmoidoscopically non-ulcerated mucosa are frequently observed in chronic ulcerative colitis. These two considerations render less likely the possibility that granulation tissue is the source of the major fraction of the lysozyme titre in ulcerative alimentary disease.