Autoantibody profiles of the experimental cohorts at 12 months of age. (a) IgG anti-ssDNA titres in the serum of Apcs-/-, wt.DNase I. Apcs-/- and ash.DNase I. Apcs-/- mice. Values are expressed in arbitrary ELISA units (AEU) related to a standard positive sample that was assigned a value of 100 AEU. Each symbol represents one mouse. (b) Anti-histone titres in the same groups of mice as in (a), and statistics were performed as described in the Materials and methods with significant differences if p < 0.05. Error bars indicate standard error of the mean. NS, not significant.