Western blot (non-reducing) was performed using Mouse anti-Human IgG Fc (CH2 domain) Secondary Antibody (Product # MA1-81864) and a 150 kDa band corresponding to Human IgG was observed in IM-9, ARH-77 and IM-9, ARH-77 conditioned medium8203 (CM) but not in Raji, Jurkat, Molt-4 and Jurkat CM which are known to have low expression. Whole cell lysate (30 µg) of MOLT-4 (Lane 1), Jurkat (Lane 2), Raji (Lane 3), IM-9 (Lane 4), ARH-77 (Lane 5), IM-9 CM (Lane 6), ARH-77 CM (Lane 7) and Jurkat CM (Lane 8) were electrophoresed using NuPAGE™ 4-12% Bis-Tris Protein Gel (Product # NP0322BOX). Resolved proteins were transferred onto a nitrocellulose membrane (Product # IB23001) by iBlot® 2 Dry Blotting System (Product # IB21001). The blot was probed with Mouse anti-Human IgG Fc (CH2 domain) Secondary Antibody (1 µg/mL) and detected by Goat anti-Mouse IgG (H+L), Superclonal™ Recombinant Secondary Antibody, HRP (Product # A28177, 1:10000 dilution) using the iBright FL1500 (Product # A44115). IM-9 and ARH-77 express and secrete IgG whereas Raji is known to express IgM. MOLT-4 and Jurkat (T-cell lines) do not express immunoglobulins (DOI:10.1002/eji.1830100305;10.3791/3573;10.1016/0022-1759(94)00286-6;PMID: 566614).