Gunnar Warfvinge

Salivary gland involvement in autoimmune thyroiditis, with special reference to the degree of association with Sjo¨gren's syndrome

From a total of 63 patients with autoimmune thyroiditis, 19 cases were further investigated to determine the degree of concomitant morphologic and functional salivary gland changes. For comparison, 21 of a total of 28 cases of primary Sjögrens syndrome were also examined. Of the 19 cases of autoimmune thyroiditis, 11 showed various degrees of salivary gland involvement on the basis of an analysis of lower lip salivary gland biopsy specimens, scintigraphy of the parotid, and unstimulated whole sialometry. Six of these cases fulfilled the criteria of primary Sjögrens syndrome. A remarkably high proportion of dark-staining acini was observed in the lower lip biopsy specimens of our patients with thyroiditis (8 of 19, 42%) and less among our patients with primary Sjögrens syndrome (5 of 21, 24%). We conclude that significant involvement of salivary glands may occur in cases of autoimmune thyroiditis, which indicates that common mechanisms may frequently be operative in the development of thyroid and salivary gland immune disease.

Histochemical visualization of mercury in the oral mucosa, salivary and lacrimal glands of BN rats with HgCl2-induced autoimmunity

BN, but not LEW, rats treated with subcutaneous injections of mercuric chloride (HgCl2) develop an autoimmune syndrome with infiltration of mononuclear cells into various organs including the oral mucosa. In the present study, we have utilized autometallographic techniques to visualize mercury in the oral mucosa, salivary and lacrimal glands of mercury-sensitive BN and -non-sensitive LEW rats injected with HgCl2. Mercury was deposited intracellularly in dendritic cells that were scattered throughout the lamina propria and submucosal connective tissue of both rat strains. In addition, mercury was detected in dendritic cells appearing within small cell clusters in the juxtaepithelial connective tissue of BN oral mucosa. In salivary and lacrimal glands, mercury was found in dendritic cells scattered throughout the stroma as well as in mononuclear cell foci. Mercury was also found in ductal epithelium. No staining was seen in any of the non-mercury-treated controls. Phenotypic analysis revealed that most mercury-laden cells were ED2+ resident macrophages and that some, but not all, of these cells expressed MHC class II antigens (RT1B).

The endothelium in early experimental contact hypersensitivity of the oral mucosa

Contact hypersensitivity is characterized by an early and specific diapedesis of mononuclear cells into the site of antigenic challenge. In order to study the functional and ultrastructural properties of the endothelium involved in the recruitment of leukocytes, Sprague‐Dawley rats were skin sensitized to DNFB; and this was followed by challenge of the oral mucosa. In vitro binding of peripheral blood mononuclear cells to high endothelial venules in lymph nodes was highly specific but no affinity of peripheral blood mononuclear cells to the vessels was observed in normal oral mucosa or in early contact hypersensitivity. However, 10 days after repeated DNFB challenge, occasional vessels bound overlaid peripheral blood mononuclear cells. Ultrasctructurally, we identified migration of mononuclear cells through small venules three h after challenge. The vessels involved, however, did not display morphological signs of activation reminiscent of high endothelial venules in lymph nodes. Mast cell degranulation was evident as early as 30 min after challenge, and a possible mechanism for mast cell‐mediated leukocyte recruitment is discussed.