reactivity of MALT lymphoma–derived immunoglobulins. (A) Seven recombinant MALT lymphoma–derived IgMs (M5, M6, M8, M11, M14, M22, and M23), 2 unmutated CLL-derived IgMs (CLL46 and CLL55), 2 mutated CLL-derived IgMs (CLL9 and CLL19), and 1 IgM control anti-erythrocyte Rhesus D were tested for reactivity in ELISAs to IgG, ssDNA, insulin, lipopolysaccharide, actin, and vimentin, as described previously.2 The OD450 nm is plotted without subtraction of background OD450 nm. MALT lymphoma–derived Igs are represented by blue lines. Red lines represent control Igs. The 4 MALT lymphoma–derived RFs are represented by dashed blue lines. (B) Immunohistochemical stainings of human TMAs, containing 21 normal human tissues, with 7 recombinant MALT lymphoma–derived IgMs, one mutated CLL–derived IgM and one unmutated CLL–derived IgM. Displayed are kidney, duodenum, liver and muscle stained with 5 μg/mL of recombinant IgM, except for CLL55, which was used at 1 μg/mL. Staining was visualized using mouse anti–human IgM (clone MH15, Sanquin), followed by the Powervision+ detection system (ImmunoVision Technologies). Images were acquired with a Leica DM5000B microscope coupled to a Leica DFC500 camera (Leica Microsystems) at the original magnification of 200×.
