1.11.1.8 CHO-K1 cells introduced with mutated TPO-MRNA 1.11.1.8 expressed in CHO cells 1.11.1.8 expressed in FTC-238 cells 1.11.1.8 expressed in High Five cells, active enzyme 1.11.1.8 expressed in High Five cells, activity similar to native enzyme when grown in presence of delta-aminolevulinic acid, enzyme in supernatant 1.11.1.8 expressed in High Five cells, enzyme insoluble and inactive 1.11.1.8 expressed in insect cells and in Chinese hamster ovary cells, activity detected when grown in presence of hematin or hemin 1.11.1.8 expressed in Sf9 cells, no activity when grown in serum free medium, active when grown in medium containing 10% fetal calf serum and 1 mg/l haematin 1.11.1.8 expression in AD-293 cell 1.11.1.8 expression in baculovirus system 1.11.1.8 expression in Chinese hamster ovary (CHO) cells 1.11.1.8 expression in CHO and LentiX-293 cell 1.11.1.8 stable expression of mutant enzymes at the surface of CHO cells