PEGylation markedly enhances the in vivo potency of recombinant human non-glycosylated erythropoietin: a comparison with glycosylated erythropoietin.

Recombinant human non-glycosylated erythropoietin (rh-ngEpo) expressed in E. coli was attached to polyethylene glycol (PEG) chains with different sizes and structures. The pharmacokinetic properties and in vivo potency of the PEGylated protein were investigated and comparisons were drawn between the conjugates and glycosylated recombinant Epo (rhEpo).

Efficient preparation and PEGylation of recombinant human non-glycosylated erythropoietin expressed as inclusion body in E. coli.

Recombinant human erythropoietin produced by mammalian cells contains about 40% carbohydrates which maintain its stability and long residence in body. However, mammalian derived Epo has low yields and high costs of production. In this article, a cost-effective strategy of producing non-glycosylated Epo from Escherichia coli and then PEGylating it to replace the role of sugar chains was investigated.

Identification of an oxidative refolding intermediate of recombinant consensus interferon from inclusion bodies and design of a two-stage strategy to promote correct disulfide-bond formation.

Dilution refolding of recombinant consensus IFN (interferon) from inclusion bodies suffers from low yield. A stable intermediate was found to mix with the correct product and to have an antiviral activity of less than 10% of the latter. This intermediate would form precipitates upon removal of the precipitation inhibitor arginine.