Serological and cellular phenotypes in B6.Sle3.OT-II mice. (A) Serum levels of antinuclear autoantibodies were assessed in 9- to 12-month-old B6.OT-II and B6.Sle3.OT-II mice (n = 8 mice per group). The dashed line indicates the mean serum levels of ANAs in B6.Sle1.FASlpr control mice exhibiting full-blown lupus (27). (B and C) The spleens of 3- to 6-month-old B6.OT-II and B6.Sle3.OT-II mice (9–12 mice per group) were also examined for the prevalence of Vβ5+, Vα2+, and CD4+ transgenic T cells (B), and their activation status, based on the surface expression of CD69 (C). Spleens of both strains did not differ in their total numbers of splenocytes, or splenic CD4 T cells. Mean ± SEM is shown in all plots. The depicted P values were derived using the Student’s t test.