Study on mechanism of salivary gland dysfunction in Sjogren's syndrome

本研究旨在探讨干燥综合征(SS)的涎腺造影、组织病理学和免疫学表现与唾液腺功能障碍的关系。唾液腺功能减退与SS相关涎腺造影结果的发生率显著相关，如点状和球状涎腺扩张。相反，涎腺导管周围淋巴细胞浸润者与无导管周围淋巴细胞者的唾液腺功能无明显差异，尽管这种组织学发现的发生与所谓的SS相关免疫异常有关。有无SS相关免疫异常的唾液腺功能，如类风湿因子、抗核抗体、抗SS-A抗体、抗SS-B抗体的发生率无明显差异。然而，唾液腺功能下降与外周血淋巴细胞中CD4/CD8比值的下降存在显著的相关性。这些结果表明，唾液腺功能障碍与点状和球形涎腺扩张的发生率有关。由于点状和球状涎腺扩张症的发生是由于唾液腺周围导管的破坏所致，故认为这种组织学改变是导致涎腺功能下降的积极因素之一。另一方面，CD4/CD8比值的降低是由于T细胞亚群的变化。这些指标在SS中的变化机制还有待进一步研究。

The present study was performed in order to investigate sialographical, histopathological and immunological findings which correlate with salivary gland dysfunction in Sjogren's syndrome (SS). Significant relationship was seen between the reduced function of salivary gland and incidence of SS-related sialographical findings, such as punctate and globular sialectasis. In contrast, no obvious difference in the salivary gland function was noted between the presence and the absence of periductal lymphocytic infiltration in the salivary gland although the occurrence of this histologic finding was associated with so called SS-related immunological abnormality. On the other hand, no obvious difference in the salivary gland function was seen between the presence and the absence of the SS-related immunological abnormality, such as the incidence of rheumatoid factor, anti-nuclear antibody, ant-SS-A antibody and anti-SS-B antibody. Significant relationship was seen, however, between the reduced salivary gland function and decrease of CD4/CD8 ratio in peripheral blood lymphocytes.These results indicate that the salivary gland dysfunction correlates with the incidence of punctate and globular sialectasis. Because it is reported that occurrence of punctate and globular sialectasis are caused by destruction of peripheral ducts of the salivary glands, it is assumed that this histological change is one of the positive factores which result in the reduced salivary gland function in SS.On the other hand , the decrease of CD4/CD8 ratio results from the change of the rates of T cell subsets. The further study should be performed to investigate the underlining mechanism which lead to the change of these rates in SS.