Synonyms
Chorionic Somatomammotropin Hormone 1, CSH1, CSB, CS-1, hCS-B, BPL, BPLP-I.

Introduction
Placental Lactogen is a polypeptide hormone that is produced by the Syncytiotrophoblasts of the Placenta, also known as chorionic somatomammotropin. It has both Growth Hormone and Prolactin activities on growth, lactation, and luteal steroid production. In women, placental lactogen secretion begins soon after implantation and increases to 1 g or more a day in late pregnancy. Placental lactogen is also an insulin antagonist.
Placental Lactogen Bovine is also capable of activating human and other heterologous GH receptors but not ruminat GH receptors.

Description
Placental Lactogen Bovine Recombinant, is a single polypeptide chain containing 199 amino acids and an additional Ala at the N-terminus having a molecular mass of 23 kDa.
Placental Lactogen Recombinant is purified by proprietary chromatographic techniques.

Source
Escherichia Coli.

Physical Appearance
Sterile Filtered White lyophilized (freeze-dried) powder.

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

Solubility
It is recommended to reconstitute the lyophilized Placental Lactogen in sterile 18M?-cm H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions.

Stability
Lyophilized Placental Lactogen Bovine Recombinant although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution Placental Lactogen should be stored at 4°C between 2-7 days and for future use below -18°C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please prevent freeze-thaw cycles.

Purity
Greater than 98.0% as determined by:
(a) Analysis by SEC-HPLC.
(b) Analysis by SDS-PAGE.

Amino acid sequence
The sequence of the first six N-terminal amino acids was determined and was found to be Ala-Glu-Asp-Tyr-Ala-Pro.

Biological Activity
Placental Lactogen Bovine is biologically active as evidenced by inducing proliferation of Nb2 cells.

Protein content
UV spectroscopy at 280 nm using the absorbency value of 0.85 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the PC GENE computer analysis program of protein sequences (IntelliGenetics).