Serum anti-histone IgG and anti-chromatin IgG. Serum samples from B6 and B6.NGAL−/− mice, 4 months after pristane or PBS challenge, were analyzed. A. Anti-histone IgG, B. Anti-chromatin IgG, were analyzed by ELISA (n=4-5 per PBS group, n=10-11 per pristane group). Data are expressed as mean ± SEM and analyzed by the Mann Whitney test. Data are representative of results from three independent cohorts, *p< 0.05, **p<0.01.