HMGB1 and systemic lupus erythematosus: As illustrated in Fig. 3a, among the 43 SLE patients testing positive for anti-HMGB1 antibodies, 7 (16 %) also had anti-dsDNA antibodies analyzed by the line blot assay, 2 (4.7 %) had anti-nucleosome Nu2 antibodies (line blot), and 2 (4.7 %) had anti-histone reactivity (line blot): 12 of the 43 anti-HMGB1-positive patients (28 %) had antibodies reactive to dsDNA and to nucleosome Nu2 and histones.