Expression of BCMA, TACI, and BAFF-R on peripheral blood B cells. Freshly isolated CD19⁺ normal B cells were stained with biotin-conjugated anti-TACI, anti–BAFF-R, anti-BCMA, or BLyS for 30 minutes on ice, washed, and incubated with RED670-streptavidin and CD27-PE (top row) or CD5-PE (middle row). Jurkat T cells stained with biotin-conjugated anti-TACI, anti–BAFF-R, and anti-BCMA followed by PE-streptavidin served as negative controls (bottom row). Isotype and fluorochrome controls were done for each sample.