mouse monoclonal IgG2a; Omni-probe Antibody (D-8) is an IgG2a κ mouse monoclonal Omni-probe antibody (also designated Omni-probe antibody) that detects the Omni-probe protein. Omni-probe Antibody (D-8) is available as both the non-conjugated anti-Omni-probe antibody form, as well as multiple conjugated forms of anti-Omni-probe antibody, including agarose, HRP, PE, FITC and multiple Alexa Fluor® conjugates. Plasmid vectors for the expression of coding regions of eukaryotic genes in E. coli, insect and mammalian hosts are in common usage. Such expression vectors often encode hybrid fusion proteins containing part prokaryotic and part eukaryotic specified proteins. For instance, the prokaryotic pRSET A, B, C and pTrc His A, B, C; baculovirus pBlue Bac His A, B, C and mammalian pEBV His A, B, C expression vectors encode fusion proteins containing polyhistidine sequences fused to insertion cDNA sequences allowing for rapid purification on nickel-charged agarose resin (2-4). Omni-probe antibodies directed to specific vector sequences mapping between the polyhistidine tag and cDNA insert sequences provide a convenient and rapid means for identification of expressed fusion proteins in different hosts.