This compound is supplied for in-vitro and preclinical research only. It is not a medicinal product. It is not approved for human or veterinary use in any jurisdiction. No therapeutic, medicinal, cosmetic, or performance-enhancement claims are made or implied. By proceeding to inquire, you confirm you are an adult researcher acquiring this compound within your own research framework. Full terms on the Research Use Only page.
TB-500
10 mg freeze-dried vial, also known as Thymosin Beta-4
Compound specifications, chemistry, and storage.
Technical specifications
Specimen format| Compound name | TB-500 (Thymosin Beta-4) |
| Also known as | TB-500, TB500, Thymosin, Thymosin Beta-4, Tβ4, T-beta-4 |
| CAS number | 77591-33-4 |
| PubChem CID | 11979658 → |
| InChI Key | WLLLUVVZAXXZIV-ZSCHJXSPSA-N |
| SMILES | Reference SMILES on COA |
| Empirical formula (Hill notation) | C212H350N56O78S |
| Molecular weight | 4963.44 g/mol (monoisotopic mass: 4961.50) |
| Salt form | Acetate (default) |
| Counter-ion content | Quantified per batch on COA. Custom salt forms (chloride, ammonium, TFA) available on quote. |
| Sequence (1-letter) | SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES |
| Sequence (3-letter) | Ser-Asp-Lys-Pro-Asp-Met-Ala-Glu-Ile-Glu-Lys-Phe-Asp-Lys-Ser-Lys-Leu-Lys-Lys-Thr-Glu-Thr-Gln-Glu-Lys-Asn-Pro-Leu-Pro-Ser-Lys-Glu-Thr-Ile-Glu-Gln-Glu-Lys-Gln-Ala-Gly-Glu-Ser |
| Length | 43 amino acids (forty-three-amino-acid peptide) |
| Weight basis | Gross weight per industry standard. Net peptide content quantified on batch COA. |
| Quantity per vial | 10 mg |
| Format | Freeze-dried white powder or thin film, sealed under inert atmosphere. Why does the vial look empty? |
| Appearance | White freeze-dried cake or powder. May also appear as a thin film on the vial wall. |
| Solubility | Water soluble, reconstituted with bacteriostatic water (1 to 2 ml typical) |
| Solution colour | Clear and colourless when correctly reconstituted |
| Purity (HPLC) | Specification ≥98.5%, tested before listing |
| Identity confirmation | LC-MS, batch-specific spectrum on COA |
| Endotoxin (LAL) | Within Ph. Eur. specification, batch report on COA |
| Storage (freeze-dried) | 2 to 8 degrees Celsius, sealed, protected from light. Avoid thermal cycling. |
| Storage (reconstituted) | 2 to 8 degrees Celsius. Use within 4 to 6 weeks. Avoid repeated freeze-thaw. |
| Shelf life | 24 months from synthesis date when storage conditions are maintained |
| Country of synthesis | EU partner facility, Ph. Eur. methodology references |
| Application | In-vitro and preclinical research only. Not for human or veterinary use. |
Wound healing & tissue regeneration
Primary research area. Studied for actin sequestration, cell migration, and angiogenic signalling in tissue-repair models.
Open research area → 02Anti-inflammatory & cytokine modulation
Secondary research area. Studied for anti-inflammatory mechanisms in chemical-injury and burn models.
Open research area →A forty-three-amino-acid peptide, and what the published research says about it.
TB-500, also written TB 500, is a naturally occurring 43-amino-acid peptide first isolated from thymus tissue and present across most cell types in mammals. Published preclinical research has investigated the peptide’s role in actin sequestration, cellular migration, angiogenesis, and tissue repair pathways across more than three decades of literature, primarily in animal injury models. The sections below summarise what the published research investigates, what Cresten supplies, and what the certificate of analysis confirms.
Where TB-500 comes from.
TB-500 is a forty-three-amino-acid peptide that occurs naturally across most mammalian tissues. It was first isolated from calf thymus in 1981 and has since been characterised in nearly every cell type studied. The peptide is one of the most abundant intracellular proteins in human cells, where it sits as a free monomer rather than as part of a larger complex. The full forty-three residues are what the published research most commonly refers to when it cites the TB-500 literature.
TB-500 is the name research suppliers most often use for the synthetic version of this same forty-three-amino-acid peptide, manufactured by Fmoc solid-phase peptide synthesis. The two names refer to the same sequence in research-supply contexts. After synthesis the peptide is purified by reversed-phase HPLC, freeze-dried, and sealed in vials under inert atmosphere. In freeze-dried form it stays stable at room temperature for a long time. The researcher reconstitutes with bacteriostatic water at the bench when ready to use.
The research base on TB 500 is substantial and predates the research-peptide market by decades. PubMed lists more than 350 papers as of 2026, with the literature concentrated in actin biology, wound-repair models, corneal injury studies, and cardiac ischaemia models. The peptide has been the subject of small clinical pilot studies in epidermolysis bullosa and pressure-ulcer indications. Most of the body of work, however, remains preclinical.
What the research looks at.
Most TB 500 mechanism research begins with one fact: it is the major intracellular sequestration partner for monomeric G-actin. Studies have shown that the peptide binds free actin monomers and prevents their polymerisation into F-actin filaments. Because actin dynamics underlie cell shape change, migration, and division, this binding is the entry point for most other mechanism work in the literature.
A second strand of research has looked at extracellular activity, where the peptide and its tetrapeptide fragment AcSDKP (acetyl-N-Ser-Asp-Lys-Pro) appear in cell-culture and animal studies of endothelial cell migration, fibroblast recruitment, and angiogenic signalling. Papers in cardiac ischaemia models have examined whether intracellular delivery affects cardiomyocyte survival after injury, with the most cited work concentrated in murine models.
"The peptide is studied as both an intracellular actin chaperone and an extracellular signal, and the research has not fully resolved how the two roles interact."
Corneal-injury research has produced the most clinically advanced literature, with pilot human studies on dry-eye and corneal abrasion indications using topical formulations. These studies are small in scale and have not advanced to large randomised trials. In every case, the published research describes investigative findings rather than approved therapeutic effects.
Where the published research does not go: there are no large randomised controlled trials in humans, no FDA or EMA approvals for any indication, and no consensus on whether the intracellular and extracellular activities are mediated by the same molecular events. TB-500 is supplied as a research compound for laboratory research only.
What the certificate confirms.
Every Cresten batch of TB-500 ships with a certificate from an analytical lab, against the test panel described on the Methodology page. The certificate that ships with your batch confirms:
The certificate format is shown on the batch verification page.
Where the published research on TB-500 lives.
PubMed indexes 350+ publications mentioning TB-500 (Thymosin Beta-4) as of 2026. Cresten does not curate a hand-selected reading list. Compound-specific selections influence which papers researchers find first; the unfiltered query, sortable by date, citation count, study type, and species, is queryable directly on PubMed.
Each result on PubMed links to the original journal record and, where available, full-text or open-access copies. Cresten supplies the compound; the literature is for the researcher to evaluate.
Open the full PubMed query →Opens at pubmed.ncbi.nlm.nih.gov in a new tab. The query string is preserved so you can refine, filter, or export from there.
What this monograph is not
This monograph summarises what the published research looks at regarding TB-500 mechanism. It is not a therapeutic recommendation. It is not dosing guidance. It is not a clinical protocol. It is not medical advice.
Cresten Labs supplies TB 500 as a research compound for lab-based research only. The decision to investigate any compound in any research framework is the researcher’s decision, within their own ethical, legal, and methodological boundaries.
Cresten makes no claim about human therapeutic use, no claim about clinical effectiveness, no claim about safety in human use, and no claim that this compound has been reviewed by any regulator for any medical use.
Frequently asked questions about TB-500
Common research-protocol and supply questions about TB 500, with answers grounded in published peer-reviewed research and Cresten Labs supply practice. All information is for in vitro and preclinical research only.
What is TB-500?
TB-500 is Thymosin Beta-4, a 43-amino-acid peptide (CAS 77591-33-4, molecular weight 4963.44 g/mol). Cresten Labs supplies TB-500 as a freeze-dried vial for in vitro and preclinical research only, with each batch verified at Janoshik Analytical.
What does research suggest TB-500 does?
Published research investigates TB-500 for sequestering G-actin and modulating actin polymerization in cell migration and tissue repair models. The compound is studied primarily in connective tissue and cardiac repair research. TB-500 is supplied for research use only and is not approved by any regulator for medical use.
What is the typical TB-500 dosage in published research?
Published TB-500 dosage in research protocols ranges from 1 to 5 mg per administration, administered subcutaneously or intramuscularly, with twice-weekly loading for 4 to 6 weeks, then weekly maintenance in connective-tissue research. Cresten Labs publishes the typical TB-500 protocol ranges as research-protocol references only; this is not dosing guidance for human use.
How do I reconstitute TB-500 for research?
Standard TB-500 reconstitution adds 1 mL plain bacteriostatic water for the 10 mg vial. Cresten ships lyophilized TB-500 vials for reconstitution by the researcher per their protocol.
What is the TB-500 half-life and how is TB-500 storage handled?
Published research reports TB-500 systemic half-life at approximately 60 hours systemic. TB-500 storage: lyophilized vial stable at room temperature for shipping; reconstituted solution stored at 2 to 8 °C and used within 28 days. The Cresten certificate of analysis lists the synthesis date, batch identifier, and the storage conditions verified for this specific batch.
TB-500 vs BPC-157: how do they compare in research?
In published research comparing TB-500 vs BPC-157, TB-500 modulates actin dynamics, BPC-157 promotes capillary formation; the two act on different parts of the repair cascade in published preclinical work. The two compounds are studied separately and in combination depending on the research question. Cresten Labs supplies both as verified research compounds.
What does research literature report about TB-500 side effects?
Published TB-500 research reports the following: preclinical models report tolerability across tested dose ranges; long-term safety data in humans is limited. Cresten Labs supplies the compound for research use only; clinical-use side-effect data should be drawn from peer-reviewed clinical trial publications, not from research-vendor pages.
Where to buy TB-500 in Europe?
Cresten Labs supplies TB-500 across the EU single market to 16 European countries. Each TB-500 batch is tested at Janoshik Analytical with the certificate of analysis published on the website before it lists. TB-500 is sold for in vitro and preclinical research only, not for human or veterinary use.
How is TB-500 verified at Cresten Labs?
Every TB-500 batch is tested at Janoshik Analytical in Czech Republic, an third-party peptide-analysis laboratory. Each batch certificate documents HPLC purity, mass-spectrometry identity confirmation, and contamination panels. The certificate publishes with the batch, before it lists.
What is the typical TB-500 stack in published research?
In published research, the typical TB-500 stack pairs the compound with BPC-157. TB-500 modulates actin dynamics, BPC-157 promotes capillary formation; the two act on different parts of the repair cascade in published preclinical work.