Certificate of Analysis & Data Sheet

Recombinant human prolactin, consists of one polypeptide chain containing 199 amino and an additional Ala at N-terminus acids was mono-pegylated and purified by proprietary chromatographic techniques as described by Oclon et al. PEDS (in press). Its molecular mass is ~ 39 kDa, however under non-denaturing conditions it behaves as 220 kDa protein due to its increased hydrodynamic volume.

E. coli

White lyophilized (freeze-dried) powder.

The protein was lyophilized from a concentrated (1mg/ml) solution with 0.02-0.03% NaHCO3.

It is recommended to reconstitute the lyophilized pegylated hPRL in sterile water or 0.4% NaHCO3 adjusted tp pH 8-9, not less than 100µg/ml, which can then be further diluted to other aqueous solutions, preferably in presence of carrier protein.

Lyophilized pegylated hPRL although stable at room temperature for several weeks, should be stored desiccated below -18C. Upon reconstitution at > 0.1 pegylated hPRL (protein part) mg/ml and up to 4 mg/ml and filter sterilization pegylated hPRL can be stored at 4C for several weeks.

Greater than 99.0% as determined by:
(a) Gel filtration analysis.
(b) Analysis by reducing and non-reducing SDS-PAGE gel.

The amino terminal sequence could not be determined as the N- terminal amino acid was covalently bound to polyethylene glycol.

The purified mono-pegylated hPRL consists of > 95% monomers as determined by gel-filtration chromatography.

PLR’s pegylated hPRL is biologically active as evidenced by inducing proliferation of Nb2 cells or Baf/3 cells stably transfected with hPRL receptors, though its activity is lesser than hPRL. However it is anticipated that its activity in vivo will be higher than hPRL due to prolonged persistence in circulation.

Less than 0.1 ng/µg (IEU/µg) of pegylated hPRL

Protein content: Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.92 as the extinction coefficient for a 0.1% (1mg of protein part/ml) solution at pH 8.0. This value is calculated by the DNAman computer analysis program of protein sequences.

This material is offered by PLR for laboratory research