Biolegend, 763714, Cell-Vive™ GMP Recombinant Human TPO (carrier-free), 25μg

Thrombopoietin (TPO) is a key regulator of megakaryocytopoiesis and thrombopoiesis. TPO binds to its receptor, the cellular homologue of the myeloproliferative leukemia virus oncogene (c-Mpl), and stimulates the proliferation and maturation of megakaryocytes. MPL does not possess kinase activity, thus the receptor associates with intracytoplasmic tyrosine kinases, janus kinase 2 (JAK2), for signal transduction. JAK2 is also important for MPL stability and cell-surface expression. TPO is able to promote the survival, self-renewal, and expansion of hematopoietic stem cells and primitive multi-lineage progenitor cells. TPO levels in blood and bone marrow are inversely related to platelet count. The regulation of TPO levels is mediated by its receptor c-Mpl (uptake and destruction). TPO is upregulated by PDGF and FGF-2, and it is downregulated by PF4, thrombospondin, and TGF-β in bone marrow stromal cells. In hepatocytes, HGF enhances TPO mRNA expression. During acute-phase response, IL-6 induces TPO transcription in the liver. Elevated plasma TPO levels exist in several hematological diseases associated with thrombocytopenia, coronary syndromes, and sepsis. Besides its hematopoietic effects, TPO is expressed in the brain where it promotes apoptosis of hypoxia sensitized neurons and inhibits neuronal differentiation by blocking NGF-induced signaling. Increased TPO concentrations are present in the cerebrospinal fluid of some patients with bacterial or viral meningitis. BioLegend Cell-Vive™ GMP Recombinant proteins are manufactured and tested in accordance with USP Chapter 1043, Ancillary Materials for Cell, Gene and Tissue-Engineered Products and Ph. Eur. Chapter 5.2.12 in a dedicated GMP facility compliant with ISO 13485:2016. Specifications and processes include:
25μg
Source: This truncated Human TPO, (amino acids Ser22(Pro26del)-Gly353, Accession # NM_000460) was expressed in 293E cells. The C-terminal contains an -TG-8H-GGQ-tag.
Molecular Mass: The 344 amino acid recombinant protein has a predicted molecular mass of approximately 37 kD. The DTT-reduced and non-reduced proteins migrate to approximately 70 kDa by SDS-PAGE. The predicted N-terminal amino acid is Ser.
N-terminalSequence Analysis: Ser-Pro-Ala-Pro-Ala-(Cys)-Asp-(Leu)-Arg-Val
Purity: ≥ 95%, as determined by Coomassie stained SDS-PAGE
Formulation: 0.1 µm filtered protein solution is in PBS, pH 7.2.
Endotoxin Level: Less than or equal to 0.1 EU per μg protein as determined by the LAL method
Residual Host Cell Protein Content: ≤ 0.500 ng/μg by ELISA
Concentration: 500 µg/mL
Storage & Handling: Unopened vial can be stored between 2°C and 8°C for up to 2 weeks, at -20°C for up to six months, or at -70°C or colder until the expiration date. For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored at -20°C or colder. Stock solutions can also be prepared at 50 - 100 µg/mL in appropriate sterile buffer, carrier protein such as 0.2 - 1% endotoxin-free BSA or HSA can be added when preparing the stock solution. Aliquots can be stored between 2°C and 8°C for up to one week or stored at -20°C or colder for up to 3 months. Avoid repeated freeze/thaw cycles.
Activity: ED50 = 0.15 - 0.6 ng/mL as measured by its ability to induce dose-dependent proliferation of MO7e megakaryocytic leukemia cells. Deep Blue Cell Viability™ Kit (Cat. No. 424701) is used to measure the proliferation. The specific activity of Cell-Vive™ GMP Recombinant Human TPO (carrier-free) is ≥1.5 x 106 IU/mg when compared against the WHO International Standard for Human TPO (NIBSC code: 03/124).
Application: Bioassay Cell Culture
Application Notes: BioLegend carrier-free recombinant proteins provided in liquid format are shipped on blue ice. Our comparison testing data indicates that when handled and stored as recommended, the liquid format has equal or better stability and shelf-life compared to commercially available lyophilized proteins after reconstitution. Our liquid proteins are validated in-house to maintain activity after shipping on blue ice and are backed by our 100% satisfaction guarantee. If you have any concerns, contact us at [email protected].
Disclaimer: BioLegend Cell-Vive™ GMP Recombinant proteins are for research use only. Suitable for ex vivo cell processing. Not for injection or diagnostic or therapeutic use. Not for resale. BioLegend will not be held responsible for patent infringement or other violations that may occur with the use of our products.
Structure: Growth Factor
Distribution: TPO is produced by the liver and kidney and is expressed in the central nervous system and bone marrow.
Function: TPO regulates the megakaryocytopoiesis and thrombopoiesis
Interaction: Megakaryocytes, platelets, hemangioblasts, hematopoietic stem cells, and endothelial cells
Ligand/Receptor: c-Mpl
Bioactivity: Measured by its ability to induce proliferation of MO7e megakaryocytic leukemia cells.
Cell Type: Embryonic Stem Cells, Hematopoietic stem and progenitors, Mesenchymal Stem Cells
Biology Area: Apoptosis/Tumor Suppressors/Cell Death, Cell Biology, Stem Cells
Molecular Family: Cytokines/Chemokines, Growth Factors
Antigen References: Avanzi G, et al. 1988. Br J Haematol. 69:359. Deutsch V.R. and Tomer A. 2006. Br J Haematol. 134:453. Drachman JG, et al. 1995. J Biol Chem. 270:4979. Li J. et al. 1999. Br J Haematol. 106:345. Kato T, et al. 1997. Proc Natl Acad Sci. 94:4669. Ehrenreich H, et al. 2005. Proc Natl Acad Sci USA. 102:862. Royer Y, et al. 2005. J Biol Chem. 280:27251. Kaushansky K. 2005. J Clin Invest. 115:3339. de Graaf CA and Metcalf D. 2011. Cell Cycle. 10:1582. Zhang J, et al. 2010. J Interferon Cytokine Res. 7:465. Lupia E, et al. 2012. Mediators Inflamm. 2012:390892. Besancenot R, et al. 2014. Blood. 124:2104.
Gene ID: 7066
UniProt: View information about TPO on UniProt.org
Other Names: Megakaryocyte Colony Stimulating Factor (MKCSF), Myeloproliferative leukemia virus oncogene ligand (Mpl-ligand), Megakaryocyte growth and development factor (MGDF), THPO, Thrombopoietin, MPLLG, MGDF, ML