Why are Symansis products more sensitive standards in quantitative immunoassays involving native human proteins?
Symansis cytokines are expressed from human cells and have post-translational modifications that mimic naturally occurring human cytokines. Quantitative immunoassays such as ELISAs use antibodies directed towards a cytokine of interest to quantitate the sample. If the antibody was raised against a cytokine expressed from E. coli or CHO cells, the antibody may recognise a region that is normally glycosylated that is normally internalised when the protein is correctly folded. As a result inaccuracies may arise when using non-human cell expressed standards (such as those expressed from E. coli) to quantitate a natural human protein. Non-human cell expressed standards may over-estimate the naturally occurring cytokine if the antigen epitopes are absent on the standard protein due to a lack of the human specific post-translational modifications. Conversely, non-human cell expressed standards may underestimate the naturally occurring cytokine if the antibody is directed towards a region that
