(A) Numbers of J558 Id+ MZ (CD21hi CD23- B220+), preMZ (CD21hi CD23+ B220+), and FO (CD21int CD23+ B220+) B cells at 0, 7, 24, 21, 28, 60, and 90 days in J558 TG mice immunized with E. cloacae. (B) Rapid migration of J558 Id+ MZ B cells to the T cell border and differentiation into plasma blasts 8 hours post E. cloacae immunization. Anti-J558 idiotype (clone TD6-4, red), anti-IgMa (green), and anti-Moma-1 (blue). (C) Numbers of J558 Id+ B cell subsets in the peritoneal cavity post immunization. (D) Numbers of J558 Id+ B1b B cells in the blood of TG mice at 0, 3, 7, 14, and 28 days after E. cloacae immunization.