Western blot was performed using Anti-CD74 Recombinant Rabbit Monoclonal Antibody (JF40-10 ), (Product # MA5-32529) and 35 kDa band corresponding to CD 74 was observed across cell lines tested except in K-562, HL-60, HEK-293 and BJ which are reported to be negative. Whole cell extracts (30 µg lysate) of Daudi (Lane 1), REH (Lane 2), K-562 (Lane 3), Raji (Lane 4), HL-60 (Lane 5), HEK-293 (Lane 6) and BJ (Lane 7) were electrophoresed using Novex® NuPAGE® 4-12 % Bis-Tris gel (Product # NP0321BOX). Resolved proteins were then transferred onto a nitrocellulose membrane (Product # IB23001) by iBlot® 2 Dry Blotting System (Product # IB21001). The blot was probed with the primary antibody (1µg/mL) and detected by chemiluminescence with Goat anti-Rabbit IgG (Heavy Chain), Superclonal™ Recombinant Secondary Antibody, HRP conjugate (Product # A27036, 1:4000 dilution) using the iBright FL 1000 (Product # A32752). Chemiluminescent detection was performed using Super Signal™ West Dura Extended Duration Substrate (Product # 34076).