Clinical associations and expression pattern of the autoimmunity susceptibility factor DIORA-1 in patients with primary Sjögren’s syndrome

Sjogren’s syndrome (SS) is characterised by B cell abnormalities and immune-mediated destruction of exocrine glands, primarily the salivary and lacrimal glands.1 2 Among the reported genetic polymorphisms associated with primary SS (pSS), the FAM167A-BLK locus distinguishes itself as an interesting candidate for further analysis based on the strong expression quantitative locus effect of pSS-associated polymorphisms on FAM167A (member A of the Family with sequence similarity 167), contrasted with only moderate or no effect on BLK .3 4 Little is known about the FAM167A gene and its relevance to rheumatic disease pathogenesis. We recently explored FAM167A and its encoded protein Disordered autoimmunity-1 (DIORA-1),4 and reported that DIORA-1 is conserved in vertebrates, has an intracellular, cytoplasmic localisation and in mice is predominantly expressed in lung and spleen—two organs with a high content of immune cells. In the present study, we investigated the expression of DIORA-1 in human immune cells and in salivary glands of patients with pSS, and assessed DIORA-1 expression in relation to pSS clinical manifestations. Notably, we observed expression of DIORA-1 in CD19+ B cells, but little or no expression in monocytes or T cells (figure 1A). DIORA-1 expression in CD19+ B cells was similar in patients with pSS and healthy donors (figure 1B). To further define the expression pattern in B cells, we analysed DIORA-1 expression in cell lines representing discrete …