What Is TB 500? Inside the Thymosin Beta-4 Fragment
TB 500 is a lab-made peptide of just seven amino acids, Ac-LKKTETQ, drawn from the actin-binding region of thymosin beta-4. That parent is a 43-residue protein found in almost every cell. Be aware that most of the research quoted in support of TB-500 was carried out on the whole protein rather than on this fragment.
Buy TB-500 Australia Labs Trust, Starting With the Parent Protein Thymosin Beta-4
Allan Goldstein's group first isolated thymosin beta-4 (Tβ4) from calf thymus, hence the thymosin name, yet it proved to be almost universal. It occurs in nearly every nucleated cell, with particularly high concentrations in platelets and white blood cells. The protein is 43 amino acids long, carries an acetylated N-terminus and has a molecular weight of around 4963 Da.
Its everyday role is sequestering actin. Tβ4 latches onto individual actin molecules (G-actin) and keeps them in reserve, which governs how quickly a cell can build the filaments it needs to change shape and move. Cell migration, wound closure and blood vessel growth all rely on cells moving to the right spot, and that is why Tβ4 is studied in each of them.
Order TB 500 Online Knowing Exactly What the Ac-LKKTETQ Fragment Is
On the research market, the TB-500 peptide usually means Leu-Lys-Lys-Thr-Glu-Thr-Gln, residues 17 to 23 of Tβ4, capped with an N-terminal acetyl group to give Ac-LKKTETQ. This segment is the central actin-binding motif. The thinking behind TB-500 is to retain the portion of the protein believed to drive actin binding and cell migration in a molecule small enough to make at low cost. It weighs around 889 Da, roughly one fifth of the whole protein.
That said, the name gets applied loosely, and some products sold as "TB-500" or "TB -500 peptide" are actually full-length thymosin beta-4. The mass shown on a certificate of analysis reveals which one you are holding, roughly 889 Da for the fragment and roughly 4963 Da for the full protein. An independent laboratory confirms the identity of every NovaPep lot by mass spectrometry, and any lot can be checked on the COA lookup page. When you buy TB-500 online in Australia from us, the 10 mg vial holds the Ac-LKKTETQ fragment, confirmed by that same test.
Shop TB-500 for Sale and Compare It With Full Thymosin Beta-4
| TB-500 | Thymosin beta-4 | |
|---|---|---|
| Chain length | 7 amino acids (Ac-LKKTETQ) | 43 amino acids |
| Mass | About 889 Da | About 4963 Da |
| Source | Synthetic fragment covering residues 17 to 23 | Natural protein, made synthetically or recombinantly for research |
| Trials in humans | None published | Phase 1 to 3 trials, among them eye drops (RGN-259) |
| WADA status | Prohibited, S2 | Prohibited, S2 |
Here is the crucial detail that most TB-500 pages leave out. The best-known studies, by Malinda and colleagues on wound closure in rats (Journal of Investigative Dermatology, 1999) and by Bock-Marquette and colleagues on heart cell survival in mice (Nature, 2004), both used full thymosin beta-4. Nobody has shown to the same standard that a seven-residue fragment delivers the same effects. In our view TB-500 should be treated as a compound in its own right that has borrowed its literature, and studies should test the fragment directly instead of presuming the two are equivalent.
Buy TB 500 With the Reported Benefits Put in Context
What gets called TB 500 benefits are, in truth, the research areas of Tβ4 biology.
- Cell migration and wound closure. In rats, Tβ4 encouraged keratinocytes and endothelial cells to migrate and sped up wound closure.
- Angiogenesis. Tβ4 helps new blood vessels form, which is a stage in every repair process.
- Cardiac models. The 2004 Nature paper described survival signalling (integrin-linked kinase and Akt) switching on in mouse heart cells following injury.
- Eye surface repair. As the eye drop RGN-259, full Tβ4 progressed to phase 3 for dry eye (ARISE-3). The co-primary endpoints were not met, though some symptom scores got better, and it has also been studied in neurotrophic keratopathy.
Not one of these findings relates to the Ac-LKKTETQ fragment in humans. So what does TB 500 do in a person? No published trial can tell us.
Order TB-500 With the Side Effect Knowledge Gaps Understood
Because no human safety study of the TB-500 fragment has ever been published, an honest list of its side effects simply cannot be compiled. The closest available data concern the full protein. Ruff and colleagues (Annals of the New York Academy of Sciences, 2010) gave healthy volunteers intravenous synthetic Tβ4, first as single doses ranging from 42 to 1260 mg and then daily for 14 days. Adverse events were uncommon and mild to moderate, and no dose-limiting toxicity appeared. A first-in-human phase 1 study of recombinant Tβ4 in healthy Chinese volunteers followed in the Journal of Cellular and Molecular Medicine in 2021.
The theoretical worry is similar to the one raised for BPC-157. Tβ4 promotes cell migration and angiogenesis, and cancer research has linked high Tβ4 expression with invasion and metastasis, for instance in a 2004 study of SW480 colon carcinoma cells and in later series of colorectal tumours. That link involves the body's own Tβ4 within tumours and does not show that TB-500 causes cancer, but it explains why long-term safety cannot be taken for granted. Product quality poses a separate risk. In April 2026 the TGA included TB-500 in its warning on unapproved peptide products, pointing to contamination and mislabelling in vials bought online.
Shop TB-500 Knowing Its WADA Status
The WADA Prohibited List places thymosin beta-4 and its derivatives, TB-500 among them, in class S2 (peptide hormones, growth factors, related substances and mimetics), so they are banned both in and out of competition. BPC-157 is listed separately in S0, and our BPC-157 side effects review deals with that compound.
Buy TB-500 and BPC-157 for Paired Research
Researchers most often study TB-500 together with BPC-157, the gastric pentadecapeptide, since the two are believed to work through separate routes. TB-500 acts via actin and cell migration, while BPC-157 acts via growth factor and nitric oxide signalling. Our side-by-side comparison of BPC-157 and TB-500 explains when separate vials are the better option and when the Wolverine Blend fits. For the 10 mg vial, the TB-500 reconstitution calculator calculates the concentration. The Wolverine blend is for sale in Australia as one 10 mg vial when the pair must run at a fixed ratio.
Order TB-500 Online in Australia From Local Stock
TB-500 is offered as a single 10 mg lyophilised vial, so the real decision is what you add alongside it. Choose the plain fragment when your study asks what Ac-LKKTETQ does by itself, and use the mass on the certificate to make sure you have the 889 Da fragment and not the full protein. Where a design compares actin-driven and growth factor routes, add a separate BPC-157 vial, or go for the Wolverine Blend if the pair will only ever be tested together. Labs wanting TB-500 near me have no need for a local supplier, because we keep it in Australian stock and ship online orders to labs across the country. Order the TB-500 10 mg vial and add bacteriostatic water to the same cart.
TB-500 belongs to our tissue repair peptide category. NovaPep sells it to adults 18+ for bench research only. It is not for people or animals, and it carries no TGA approval for any therapeutic use.
What Is TB 500? Inside the Thymosin Beta-4 Fragment FAQ
What exactly is TB 500?
TB-500 is a lab-made peptide of seven amino acids, Ac-LKKTETQ, corresponding to residues 17 to 23 of thymosin beta-4. This section forms the protein's central actin-binding motif. Researchers study it in the context of cell migration, wound healing and blood vessel growth, and it has no approval as a medicine.
Are TB-500 and thymosin beta-4 identical?
No. Thymosin beta-4 is the complete protein of 43 amino acids (about 4963 Da), while TB-500 is a seven-residue piece of it (about 889 Da). The full protein was used in most published studies, so look at the molecular weight on a certificate of analysis to confirm which one you have.
What side effects are known for TB 500?
Nobody has published a human safety study of the TB-500 fragment. For full thymosin beta-4, a 2010 phase 1 trial found adverse events were infrequent and mild to moderate. Remaining concerns are partly theoretical, tied to its roles in cell migration and angiogenesis, and partly practical, such as contamination in unverified products.
What benefits are claimed for TB 500?
The claimed benefits derive from animal and cell studies of full thymosin beta-4, covering quicker wound closure, cell migration, angiogenesis and heart cell survival. Controlled human trials have not shown whether the TB-500 fragment produces the same effects.
Is TB-500 prohibited in sport?
It is. Thymosin beta-4 and its derivatives, TB-500 included, fall under S2 of the WADA Prohibited List and are banned in and out of competition. The S2 class takes in peptide hormones, growth factors, related substances and mimetics, and the ban applies to the substance regardless of how a product is labelled.
Can TB-500 be bought online in Australia?
Yes, for laboratory research. NovaPep sells TB-500 online as a 10 mg lyophilised vial from Australian stock, and every lot comes with an independent mass spectrometry and purity certificate. Before starting, confirm the certificate shows about 889 Da, the mass of the fragment. It has no TGA approval and is not for human or veterinary use.