Repair & Recovery
TB-500
Also published as Thymosin Beta-4 fragment, Ac-LKKTETQ, TB4 fragment
A short synthetic acetylated peptide corresponding to the actin binding region of thymosin beta-4. It is routinely sold and discussed as though it were thymosin beta-4 itself, which it is not.
Where it came from
Derived from thymosin beta-4, a 43 amino acid actin sequestering protein first isolated from calf thymus in 1981 and present in most mammalian cell types.
What the literature examines
- Actin sequestration and cell migration in vitro
- Corneal and dermal wound repair models
- Cardiac repair and angiogenesis after induced infarction in rodents
- Hair follicle and epithelial cell migration
State of the evidence
Full length thymosin beta-4 has been through early clinical trials in ophthalmic and dermal indications. The short TB-500 fragment has not been trialled clinically in its own right.
What a buyer should know
TB-500 and thymosin beta-4 are not interchangeable, and evidence for one is not evidence for the other. Anything a supplier tells you about thymosin beta-4 clinical work does not transfer to a seven residue fragment. It is on the WADA prohibited list under S2.
Handling and stability
Lyophilised powder, readily soluble in water. Hold reconstituted material cold. Freeze thaw cycling degrades short peptides faster than most buyers expect.
Sequence
Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln (core actin binding motif)
Read it yourself
We do not publish a curated citation list, because a hand picked list of papers is a sales tool. These links run a live query against the public databases, so you see everything, including the results that do not suit us.
Supplied for laboratory research use only. Nothing on this page is a dose, a protocol or a claim of effect in humans, and nothing here is medical advice. Read our research use policy.