Anti-Sm B-1–cell activation in Fas^lpr mice after peritoneal cell transfer. (A) 2-12H/Fas^lpr peritoneal cells were stained for CD19 and CD11b, and the CD19⁺ CD11b⁺ B-1 cells and CD19⁺ CD11b^– B-2 cells were sorted and transferred to Fas^lpr recipient mice. Two weeks after transfer, anti-Sm ASCs in the bone marrow, spleen, MLN, and LP were quantified (± SEM) by ELISpot. ND indicates none detected. (B) Unsorted peritoneal cells from 2-12H/Fas^lpr mice were transferred to wild-type (wt) or Fas^lpr recipient mice. ELISA was used to measure (± SEM) serum IgMa+ anti-Sm (inset), and ELISpot was used to quantify (± SEM) anti-Sm ASCs from BM, spleen, MLN, and LP. (C) The same as panel B except that 2-12H peritoneal cells were transferred to wt or Fas^lpr recipients. Asterisks indicate the differences (P < .05) between wt and Fas^lpr recipients.