What Is TB-500? Thymosin Beta-4 Fragment Research Guide
TB-500 is a synthetic peptide corresponding to the active actin-binding region of Thymosin Beta-4, a naturally occurring protein found in nearly all human and animal cells. Researchers frequently pair it with BPC-157 in study designs, but the two act through quite different mechanisms. This guide sets out what TB-500 is, what the literature investigates, and how it is handled at the bench.
Sequence and origin
TB-500 is a seven-amino-acid fragment (LKKTETQ) of the 43-residue Thymosin Beta-4 protein, and it is this short domain that carries the actin-binding activity studied in the literature.
Because it is a fragment rather than the full protein, TB-500 is smaller, cheaper to synthesise and more soluble — the practical reasons it dominates research procurement over full-length Thymosin Beta-4.
Mechanism studied in the literature
The published work centres on actin sequestration: TB-500 binds G-actin and influences the polymerisation dynamics that drive cell migration.
Downstream, studies examine endothelial cell migration and new vessel formation, fibroblast recruitment in wound models, and modulation of inflammatory markers in injured tissue.
TB-500 is often contrasted with BPC-157 because BPC-157 work focuses on growth-factor and nitric-oxide pathways, while TB-500 work focuses on cytoskeletal dynamics. Researchers combining them are usually testing complementary rather than overlapping mechanisms.
Handling, reconstitution and storage
TB-500 is supplied lyophilised and is highly water-soluble. Reconstitute with bacteriostatic water added gently down the vial wall, and swirl rather than shake.
Store sealed vials frozen and reconstituted solution at 2-8 °C, protected from light. As with all peptides, label the vial with concentration and date at the moment of reconstitution.
Frequently asked questions
- What is the difference between TB-500 and BPC-157?
- In the research literature TB-500 is studied for actin binding and cell migration, while BPC-157 is studied for angiogenic and growth-factor signalling. They are different molecules with different mechanisms, which is why study designs often examine them side by side.
- Is TB-500 the same as Thymosin Beta-4?
- No. TB-500 is a short synthetic fragment (LKKTETQ) of the full 43-amino-acid Thymosin Beta-4 protein. It reproduces the actin-binding domain, not the whole protein.
- How is TB-500 stored?
- Sealed lyophilised vials are stored frozen. Once reconstituted with bacteriostatic water, keep the solution refrigerated at 2-8 °C, away from light, and avoid repeated freeze-thaw cycles.
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All information on this page is provided for laboratory and educational reference only. Peptides Lab SA (PTY) Ltd supplies compounds strictly for in-vitro research use. Nothing here is medical advice, a dosing recommendation, or a claim of human safety or efficacy.