JAG2 expression. (A) Representative result of RT-PCR experiments assessing the levels of JAG2 transcripts in JAG2-negative (MUTZ5-ALL) and normal plasma cells (PC) and JAG2-positive (KMSM-1 and -2, K620, RPMI 8226) cell lines. GAPDH levels were used to normalize the amount of cDNA present in each tube. (B) Comparative immunostaining results. Normal nonpurified (1-2) and MM (5-6) plasma cells stained with an anti-CD138 (1,5) and anti-JAG2 (2,6). Panels 3 and 4 are a representative (K620) MM cell line stained with the anti-JAG2 (3) and goat isotype (4) antibodies; panels 7 and 8 show double color staining anti-CD138 (Fast Red) and -JAG2 (DAB) of an MM cell line (KMSM-1) (7) and a paraffin section from an MM patient sample (8). (C) Western blot analysis of normal PC, a NIH 3T3 cell line overexpressing JAG2, and 7 MM cell lines (K620, KMSM-1 and -2, RPMI 8226, U266, MM1-S and -R).