Surface IgA expression is maintained on plasma cells. (A) Surface expression of IgA and IgG on CD19⁺ and CD19^– plasma cells from BM. Control is isotype control. (B) The gating strategy for sorting rotavirus-specific plasma cells. (C) Sorted rotavirus-specific cells secrete rotavirus-specific IgA (top) compared with control (bottom) (200 rotavirus-specific cells were seeded). The graph depicts the frequency of IgA⁺ rotavirus-specific plasma cells of total plasma cells (n = 9).