Apoptosis and related gene expression in minor labial salivary gland of patients with primary Sjogren′s syndrome / 中华风湿病学杂志

ABSTRACT

Objective To study the roles of apoptosis and expression of the related genes in minor labial salivary gland of patients with primary Sjogren′s syndrome (pSS). Methods Biopsies of minor submucosal labial salivary gland (SG) were obtained from 30 patients with pSS and 10 control individuals. The in situ end labeling and immunohistochemical staining were used to detect the apoptotic cells and the expression of Fas, FasL and Bcl-2. Results The percentage of apoptotic acinar and ductal epithelial cells (AEC and DEC) in labial salivary glands of patients with pSS was significantly higher than that of control respectively, but the percentage of apoptotic infiltrating mononuclear cells (IMC) showed no significant difference compared with that of control, pSS AEC and DEC showed increased expression of Fas/FasL and decreased expression of Bcl-2, whereas pSS IMC showed increased expression of Fas, Fas/FasL and Bcl-2. There was significant positive correlation between the percentage of apoptotic cells and the cells expressing Fas and FasL in pSS AEC DEC and IMC, respectively, and there was significant negative correlation between the percentage of the apoptotic cells and that of cells expressing Bcl-2 in pSS DEC and IMC, but there wasn′t correlation between the percentage of the apoptotic cells and that of cells expressing Bcl-2 in pSS AEC. Conclusions The apoptotic cells increased in the epithelial cells and decreased in IMC of the labial salivary glands may be one of the mechanisms leading to the glandular destruction found in pSS. In pSS labial salivary glands, the expression of Fas and FasL may promote apoptosis, while the expression of Bcl-2 may inhibit apoptosis. The increased expression of Bcl-2 in pSS IMC indicates that IMC may be able to escape apoptosis, resulting in inflammatory cell foci.