HEK293T cells were transfected with the pCMV6-ENTRY control (Left lane) or pCMV6-ENTRY B2M (RC207587, Right lane) cDNA for 48 hrs and lysed. Equivalent amounts of cell lysates (5 ug per lane) were separated by SDS-PAGE and immunoblotted with anti-B2M. Positive lysates LY401311 (100 ug) and LC401311 (20 ug) can be purchased separately from OriGene.