Parotid gland of Sjögren's syndrome

Involvement of Fas/Fas ligand in the induction of apoptosis in chronic sialadenitis of minor salivary glands including Sjögren's syndrome

The role of apoptosis and contribution of Fas/FasL systems in the pathogenesis of Sjogren's syndrome (SS) are still controversial. With serial sections, we explored apoptosis assessed by the dUTP nick end labeling (TUNEL) method and expression of Fas and FasL by immunohistochemistry, and compared their distribution in minor salivary gland (MSG) of SS and sialolithiasis (SIL) patient tissues. Fas and FasL were co-localized in ductular and acinar cells of SS and SIL TUNEL+ cells co-distributed with the Fas and FasL expressing cells in ductular and acinar cells of SS in the vicinity of lymphocytic infiltration, while not in those of SIL Moreover, to morphologically confirm apoptosis, we identified TUNEL-positive(+) cells in the MSGs of SS at the ultra structural level by applying an inversion method to paraffin-embedded sections stained by TUNEL method. Surprisingly, these cells did not show characteristic apoptotic figures although TUNEL products were deposited on the hyperchromatin of acinar and ductular cells. On the other hand, acinar and ductular cells of SIL included clusters of TUNEL+ apoptotic bodies as did those cells by phagocytosis or having fallen into the ductular lumen. These findings suggest that Fas and FasL expressed in ducts and acini of chronic sialadenitis in SS patients induce apoptosis, possibily in an autocrine and/or paracrine manner.

Sialochemistry in Sjögren's syndrome: a review

Sjögren's syndrome (SS) is an autoimmune exocrinopathy. The salivary glands are the site of activated T- and B-lymphocytes, along with gradual parenchymal destruction, diminished flow and altered composition of the secretory product. At present, sialochemistry has achieved no significance for the evaluation of SS patient. However, the number of sialochemical publications is steadily growing. This study review current sialochemical findings in patients with SS and relate the observations to the present concept of diagnosis, pathogenesis and prognosis of SS. An ideal combination of the collection of low-stimulated pure secretion, measurements of absolute flow-rates, and biopsy from the same glands seem to be unobtainable in SS patients. But two procedures may be appropriate: stimulated parotid secretion combined with parotid biopsies, or absorbance of low-stimulated labila saliva combined with labial gland biopsy. Sufficient data on disease-specific alterations in salivary composition in SS are still lacking. However, detection of specific changes in protein synthesis or in glycosylation as well as the detection of inflammatory cell products should be possible with the use of sensitive biochemical assays.

Ultrastructural and immunocytochemical aspects of lymphocytic submandibulitis in the non-obese diabetic (NOD) mouse

The submandibular glands of female non-obese diabetic (NOD) mice (22-26 weeks of age) were studied by light and electron microscopy. Mononuclear cells consisting mostly of lymphocytes were recognized in and among the acini and secretory ducts. Some parts of the secretory ducts and mucous acini surrounded by lymphocytes showed destructive changes. In the secretory ducts lymphocytes invaded the duct epithelial lining and the duct lumen was occluded by these cells. The duct epithelial cells in such lesions were extremely distorted and tonofilament bundles running in various directions were present in the cytoplasm. Lymphocytes were in close contact with the duct epithelial cells. In the mucous acini some acinar cells, which appeared to be compressed by the infiltrating lymphocytes, showed degenerative changes. Immunocytochemical study revealed that both T- and B-lymphocytes were involved, T-lymphocytes tending to occupy the center of the infiltrate, while B-lymphocytes occupied the periphery. Although autoantibody against duct epithelial cells was identified, damage to duct epithelial cells was not correlated with the presence of this antibody. The morphological changes in the submandibular gland of the NOD mouse are very similar to those reported in the salivary gland of patients with Sjögren's syndrome.

Light and ultrastructural features of lymphoepithelial lesions of the salivary glands in Mikulicz's disease

This investigation deals with the histogenesis of the so-called 'epimyoepithelial islands' in Mikulicz's disease of the major salivary glands and is based on light and electron microscopic study in six patients. The 'epimyoepithelial islands' represent collapsed acini prior to their complete involution and disappearance, the intraductal cellular proliferation, stratification and differentiation into luminal and peripheral myoepithelial cells with partial and complete obliteration of their lumina and finally, cord-like proliferation and formation of nests of residual pluripotential cells showing squamous metaplasia and occasional myoepithelial cell differentiation. A pink, homogeneous and hyaline material on light microscopic examination is multilayered and extracellular and is in close association with the basal lamina when viewed with electron microscope.

Primary Sjogren syndrome: clinical and immunopathologic features

Primary Sjogren syndrome is an autoimmune condition in which dry eyes (keratoconjunctivitis sicca) and dry mouth (xerostomia) result from lymphocytic infiltration of lacrimal and salivary glands. Clinical and laboratory features of 60 primary Sjogren syndrome patients seen at our clinic during the past three years are presented. These patients illustrate the wide spectrum of extraglandular features that may occur as a result of lymphoid infiltration of lung, kidney, skin, stomach, liver, and muscle. They further emphasize the difficulty in classifying a patient as primary or secondary Sjogren syndrome (ie, sicca symptoms associated with systemic lupus erythematosus, rheumatoid arthritis, or scleroderma), particularly early in the disease course. As an initial step in understanding the pathogenesis, the lymphocytes that infiltrate the salivary glands and lymph nodes were characterized by using monoclonal antibodies that recognize distinct lymphocyte subsets and by using in vitro functional assays. These studies have demonstrated that affected tissues have infiltrates of T cells with helper/inducer activity and with a high frequency of "activation antigens." The immunohistologic techniques are useful in differentiating "benign" and "pseudolymphoma" lesions (both due predominantly to T cells) from non-Hodgkin lymphoma (usually due to B-cell infiltrates). Although there is no "cure" for primary Sjogren syndrome patient's symptoms may be significantly improved by measures aimed at prevention of ocular and dental complications and by the recognition of extraglandular features that may be amenable to specific treatment.

Studies of autoimmune induction in the rat lacrimal gland

Induction of autoimmunity in the rat lacrimal gland was presently assessed. Antibodies to lacrimal gland extract were detectable in 58% of the immunized rats. Skin tests were positive at 4 week postimmunization in 70% of the animals. Histological observations revealed the presence of mononuclear cell infiltrates surrounding the ductal and acinar epithelium at 2--6 weeks.

A simple device measuring differences in level in the oesophagus

A device for measuring the difference in level between the pressure transducer and a point of measurment is described. It can be used in oesophageal manometry with waterfilled catheters to measure and compensate for superimposed hydrostatic pressure. The practical application of the method is illustrated.