Figure 3

Intra and extra-cellular expression of EPO after the addition of secretory signal sequence. Total protein was extracted and subjected to ELISA. Optical density was measured at 450 nm. (A) Relative extra-cellular EPO expression showing that after the addition of signal peptide secretion of EPO into the medium is dramatically increased. (B) Comparison of intra-cellular EPO expression with (pcDNA3.1-SS-EPO) and without signal peptide (pcDNA3.1-EPO) expression vectors. Intra-cellular expression of protein is also slightly increased after the addition of signal peptide.