Sjögren’s disease (SjD) is a systemic autoimmune disease characterised by oral and ocular dryness. In addition to these typical dryness symptoms, various other organs can also be affected. Currently, there is no approved treatment for the disease. For diagnosis and classification, a salivary gland biopsy is often examined. In this biopsy, the focus score is assessed: the number of clusters of immune cells surrounding the ducts per unit area. Salivary gland biopsies are also important for gaining a better understanding of the disease and for developing medical treatment.
The aim of the research described in this thesis of Uzma Nakshbandi was to gain more insight in the salivary gland biopsy findings in patients with SjD, and to evaluate the role of these findings in the diagnosis, classification, and stratification of patients.
Nakshbandi showed that in addition to the focus score, other abnormalities in the salivary gland biopsies were relevant. These included: the presence of B-cells in the ductal epithelium of the salivary gland, a relative increase in plasma cells which produce IgG antibodies, and the presence of germinal centres (structures where memory B-cells are generated). These features were observed in both labial and parotid gland biopsies and provided added value for the diagnosis and classification of SjD. Moreover, these Sjögren-specific salivary gland changes were significantly more frequent in patients who also showed serological abnormalities, such as the presence of autoantibodies. Additionally, these histopathological changes were also present in children with Sjögren, often more clearly than in adults.
In addition, the study investigated whether treatment with abatacept, a medication that suppresses the immune response, had an effect on the salivary gland tissue. However, abatacept did not lead to major changes after 24 weeks of treatment in the biopsy findings, nor could the biopsy predict which patients would respond to treatment.
