Recombinant Human Thrombopoietin/THPO Protein

Product Discontinued

Recombinant Human Thrombopoietin/THPO Protein Summary

• Description: A biologically active protein to THPO.
• Specificity: Thrombopoietin HCX migrates as a broad band between 75 and 100 kDa in SDS-PAGE due to post-translation modifications, in particular glycosylation. This compares with unmodified Thrombopoietin that has a predicted molecular mass of 35.5 kDa. Thrombopoietin HCX contains N- and O-linked oligosaccharides.
• Preparation Method: A DNA sequence encoding the human Thrombopoietin (TPO) protein sequence (containing the signal peptide sequence, and the mature TPO sequence) was expressed in modified human 293 cells.
• Details of Functionality: The ED50 of TPO is typically 2.5 to 10 ng/ml as measured in a cell proliferation assay using the human growth factor dependent TF-1 cell line.
• Protein/Peptide Type: Biologically Active Protein
• Gene: THPO

Applications/Dilutions

• Dilutions:
  • Block/Neutralize
  • Functional
  • Western Blot
• Application Notes: This protein is functionally active and can be used for Blocking and Neutralizing. It can also be used for Western Blot. Thrombopoietin HCX separates into a number of isoforms with a pI less than 5.0 in 2D PAGE due to post-translational modifications, in particular glycosylation. This compares with the unmodified Thrombopoietin that has a predicted pI of 9.69.

Reactivity Notes

This is a Human protein

Packaging, Storage & Formulations

• Storage: Store at -80C. Avoid freeze-thaw cycles.
• Concentration: LYOPH
• Reconstitution Instructions: Reconstitute with 0.5 ml sterilized PBS. After reconstitution the buffer solution will contain 1% human serum albumin and 10% trehalose already present in the vial.

Alternate Names for Recombinant Human Thrombopoietin/THPO Protein

• Megakaryocyte colony-stimulating factor
• Megakaryocyte growth and development factor
• megakaryocyte stimulating factor
• MGDF
• MGDFC-mpl ligand
• MKCSF
• MK-CSF
• ML
• MPL ligand
• MPLLG
• MPLLGMGC163194
• Myeloproliferative leukemia virus oncogene ligand
• THCYT1
• THPO
• thrombopoietin nirs variant 1
• Thrombopoietin
• Tpo
• TPOMKCSF

Background

Thrombopoietin (TPO), a hormone predominately expressed in liver and bone marrow stromal cells, is the principal regulator of proliferation and differentiation of megakaryoctytes, and is the major cytokine involved in platelet production. TPO has also been shown to pay a role in production of primitive pluripotent stem cells and progenitor cells, such as erythroid and myeloid progenitor cells. Human TPO cDNA encodes a 353 amino acid precursor protein that is cleaved upon secretion from the cell. Mature human TPO is a 95kDa glycoprotein that comprises two domains, a receptor binding domain that shares homology with erythropoietin, and a heavily O- and N-linked glycosylated region at the carboxy terminus. Potential clinical applications for TPO include the in-vivo expansion of platelet numbers following thrombocytopenia inducing effects of chemotherapy. TPO also shows promise in the ex-vivo expansion of autologous haematopoietic progenitor cells prior to re-infusion into patients with conditions such as multiple myeloma and NHL following myeloabalative chemotherapy. This is a HCX protein. HCX Expression System Details HCX proteins mimic the proteins in the human body because they are expressed from human, rather than animal, insect or bacterial cells. This process gives them human post-translational modifications. Recombinant DNA techniques allow a human protein with the correct amino acid sequence to be expressed in a non-human cell line. However, non-human cells lack the appropriate cellular machinery, such as specific glycosyltransferases, necessary to produce the correct human post-translational modifications of a protein. An extreme example is seen in E. coli cells, which produce recombinant proteins with no glycosylation, as the above figure illustrates. Rodent and yeast cells are able to glycosylate proteins, but they are still different from glycosylation in human cells. Expression System Resultant Proteins Human (e.g. K562, HEK293) Correct amino acid sequence Human post-translational modifications Rodent (e.g. CHO, NSO) Correct amino acid sequence Some natural glycosylation - not human-like Yeast (e.g. Pichia) Correct amino acid sequence Some natural glycosylation - not human-like E.Coli Correct amino acid sequence No PTMs Although there have been significant attempts to make non-human cell derived cytokines more human-like, there is a growing awareness that in many instances, particularly in therapeutics, cytokines should mimic those found in the body as closely as possible. Purified Thrombopoietin HCX consists of greater than 35% carbohydrate by weight.

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Peptides and proteins are guaranteed for 1 year from date of receipt.

Bioinformatics

• Gene Symbol: THPO