Recombinant Human TPO Protein

Thrombopoietin (Tpo), also known as Megakaryocyte Growth and Development Factor (MGDF), is a cytokine that regulates megakaryocyte production and platelet generation. TPO acts early in megakaryocyte lineage commitment, promoting the proliferation of megakaryocyte progenitor cells and increasing megakaryocyte ploidy. However, TPO does not influence platelet release from mature megakaryocytes [1].

TPO plays a pivotal role in hematopoietic Stem Cell (HSC) regulation (Figure 1). Studies reveal that TPO signaling in HSCs maintains stem cell quiescence to preserve their longevity or drives HSC expansion during critical events (e.g., post-transplantation). In both scenarios, TPO modulates cell cycle transitions. The TPO-Mpl signaling pathway impacts mitochondrial metabolism, and this metabolic regulation may influence HSC lineage differentiation. Furthermore, TPO signaling stimulates HSC self-renewal, highlighting its therapeutic potential for treating hematopoietic disorders characterized by impaired stem cell function, such as aplastic anemia, through TPO-mimetic drug development.

In HSC ex vivo culture, TPO enhances cell expansion. While TPO alone minimally impacts proliferation in single-cell culture systems, its combination with SCF, IL-3, and IL-6 significantly boosts HSC clonal growth (Table 1). Recent advances have further optimized cytokine cocktail formulations incorporating TPO for improved HSC culture outcomes [4,5].

Table 1. Effects of TPO on HSC colony formation in vitro [3].

Product Features

• High purity

• Exceptional bioactivity

• Low endotoxin

• Sterile, mycoplasma-free

Product Performance Validation

Figure 2. SDS-PAGE analysis under reducing conditions confirms >90% purity.

Figure 3. Mo7e cell proliferation assay: T&L product shows >5x activity vs. Imported competitors.

Product Information
Synonyms: thrombopoietin, C-mpl ligand, Megakaryocyte colony-stimulating factor (MKCSF), MGDF,THCYT1, MPLLG
Accession: P40225
Amino acid sequence: S22-L195 (P157N & R164N) Tag: His tag at the C-terminus
Expression system: HEK293 cellsMolecular weight: 19.5kDa
Purity: > 90% as determined by SDS-PAGE
Endotoxin: < 0.1 EU per 1 µg of protein (LAL method).
Activity: Measured in a cell proliferation assay using MO7e human megakaryocytic leukemic cells, corresponding to a specific activity of ≥ 5.0×106 IU/mg.
Formulation：Lyophilized from sterile PBS (pH 7.4), typically supplemented with 6% - 8%mannitol as a protectant.

Stability & Storage
Lyophilized powder: Stable for up to 6 months when stored at -20°C under sterile conditions after reconstitution, or 12 months at -80°C.
Reconstitution: Dissolve in sterile water for injection, normal saline, or PBS. Maintain a diluted concentration ≥ 100 µg/mL.
Handling: Aliquot to avoid repeated freeze-thaw cycles.

Intended Us
For research and manufacturing purposes only.

References

[1] de Graaf CA, Metcalf D. Thrombopoietin and hematopoietic stem cells. Cell Cycle. 2011;10(10):1582-9. doi:10.4161/cc.10.10.15619.

[2] Nakamura-Ishizu A, Suda T. Multifaceted roles of thrombopoietin in hematopoietic stem cell regulation. Ann N Y Acad Sci. 2020;1466(1):51-58. doi:10.1111/nyas.14169.

[3] Sitnicka E, et al. The effect of thrombopoietin on murine hematopoietic stem cells. Blood. 1996;87:4998-5005. PMID:8652812.

[4] Pineault N, et al. Cytokine effects on cord blood CD34+ expansion. Cytotherapy. 2010;12:467-80.

[5] Ohmizono Y, et al. TPO synergizes with SCF/flt3 ligand in cord blood HSC expansion. Leukemia. 1997;11:524-30. doi:10.1038/sj.leu.2400588.