pcDNA?4/HisMax is specifically designed to maximize protein expression in a variety of mammalian cells. The vector contains the QBI SP163 translational enhancer to increase expression levels two- to five-fold above those seen with the promoter alone (Figure 1). In addition to SP163-enhanced expression, pcDNA?4/HisMax includes a cleavable N-terminal Xpress? tag for rapid detection of recombinant protein with an Anti-Xpress? Antibody (Figure 2). pcDNA?4/HisMax is available TOPO? Cloning-ready for five-minute cloning of Taqamplified PCR products.