Autoimmunity

Autoimmune diseases, including more than 100 known pathologies with various manifestations, concern 5-8% of the population worldwide and are responsible for an important burden in terms of morbidity, mortality and healthcare costs. Some autoimmune diseases are organ-specific (such as type 1 diabetes) whereas others are systemic (i.e. able to affect any system in the body), but they all have in common the dysregulation of the immune system.

Among the systemic autoimmune diseases, Sjogren’s syndrome is the 2nd most common (0.01-0.3% of the adult population) but still faces unmet diagnostic, therapeutic and follow-up needs. Inflammatory infiltration of the salivary and lacrimal glands responsible for dry eyes and mouth is the main feature of Sjogren’s syndrome, but apart from this classical feature, the clinical spectrum is broad (e.g. rheumatologic, neurologic, bronchiolar, pulmonary, haematological or renal manifestations…).

As all systemic autoimmune diseases, Sjogren’s syndrome has a complex pathophysiology, but what is commonly accepted nowadays, is that B cell activation seems to have a pivotal pathological roleas illustrated by the production of many autoantibodies in patients. Hence, we are interested in deeply characterising the autoreactive humoral response from patients with different phenotypes in order to improve our understanding of the pathological mechanisms at work. We think that these new elements should allow the identification of new biomarkers, therapeutic targets and/or subsets of patients, which will be very useful in addressing the main pitfalls in Sjogren’s syndrome management.