Since HMGB1 is an alarmin, whose circulating levels may be elevated during chronic inflammation, autoimmune diseases, or preeclampsia, in this investigation, we preliminarily tested HMGB1 expression by Western blot in sera from patients with APS patients, compared with women with pregnancy morbidity and healthy blood donors (Figure 1(a)). This evidence concerns the gene HMGB1 and autoimmune polyendocrinopathy.