Isolation and analysis of plasma B cells in zebrafish. (A) Kidneys were isolated from adult cd45:DsRed;blimp1:eGFP fish and analyzed by flow cytometry. The GFP/DsRed profile of cells in the combined lymphocyte and precursor fractions is shown. The indicated population of cells was sorted from individual fish and analyzed by qRT-PCR. (B) Average expression (plus range) of IgM, pax5, irf4, xbp1, or cd40 relative to ef1α (ΔCt) for cells from the Blimp1⁺CD45⁻ fraction from two individual fish using whole-kidney cDNA as a comparison. These results are representative of 3 independent experiments.