Characterization of TACI transgenic mice. (A) Schematic representation of the murine TACI transgenes. (B-C) Representative FACS analysis of TACI surface expression in the 2 WT Tg founder lines (F19 and F25) and the 2 A144E Tg founder lines (F43 and F59) (B), and of CD3⁺ and B220⁺cells (C) in splenocytes of TACI^+/+, TACI^−/−, and TACI transgenic mice.