About TB-500
TB-500 is a synthetic peptide corresponding to residues 17 to 23 of thymosin beta 4, the actin binding region of that naturally occurring protein. It is supplied as a lyophilized powder of high analytical purity and is studied in laboratory settings in connection with actin dynamics, cell migration and angiogenic signaling. Peptsche supplies TB-500 strictly as a research material for controlled laboratory investigation.
Available Sizes
TB-500 is supplied as high purity lyophilized powder in a sealed glass vial, accompanied by batch specific analytical documentation.
- TB-500 10 mg Vial
Product Specifications
| Product | TB-500 (10 mg) lyophilized powder in sealed glass vial |
| Application | Research peptide studied in actin binding, cell migration and angiogenesis models |
| Appearance | Solid white powder |
| Chemical Formula | C38H68N10O14 |
| Molecular Weight | 889.0 g/mol |
| CAS Number | 885340-08-9 |
| PubChem CID | 62707662 |
| Sequence | Ac Leu Lys Lys Thr Glu Thr Gln OH (thymosin beta 4 residues 17 to 23) |
| Synonyms | TB500, TB 500, TB-500 acetate, Ac-LKKTETQ |
| Purity | 99% or greater by HPLC, verified per batch |
| Storage | Store sealed at 2 to 8 °C, protected from heat, light and moisture |
| Regulatory Status | Research use compound. Not approved for human or veterinary use in any jurisdiction. |
What is TB-500?
TB-500 is a short synthetic peptide of seven amino acid residues, acetylated at the N terminus. Its sequence reproduces the actin binding domain of thymosin beta 4, a 43 residue protein present in most mammalian cell types and one of the most abundant intracellular peptides identified in the body.
Research interest in this fragment arose from work on the parent protein. Thymosin beta 4 functions as the principal actin sequestering molecule in many cells, binding monomeric G actin and regulating its availability for polymerisation. Investigators isolated the binding region to examine whether the shorter sequence retained measurable activity in experimental systems, and TB-500 corresponds to that fragment.
The published literature on both the parent protein and the fragment is preclinical, comprising in vitro assays and animal models. TB-500 is not an approved therapeutic agent in any jurisdiction. In the United States it appears on the Food and Drug Administration list of bulk drug substances withdrawn from consideration for compounding on the basis of potential immunogenicity and aggregation concerns, and researchers should be aware of that classification.
TB-500 Mechanism of Action (Research Only)
Unlike compounds that act at a defined cell surface receptor, TB-500 is studied primarily in terms of intracellular protein interaction, specifically its relationship with the actin cytoskeleton.
Actin Binding and Cytoskeletal Dynamics
The parent protein thymosin beta 4 binds monomeric actin and holds it in a sequestered pool, modulating the balance between free monomer and polymerised filament. The actin binding motif retained in TB-500 is the structural basis for research interest in the fragment, and cytoskeletal reorganisation is the mechanism most consistently examined across published work.
Cell Migration Research
Work published in the FASEB Journal examined directional migration of human umbilical vein endothelial cells in the presence of thymosin beta 4 and reported stimulation of migration in that assay system. Because cell migration depends on coordinated cytoskeletal remodelling, this line of research connects directly to the actin binding mechanism above.
Angiogenic and Tissue Response Signaling
Studies published in the Journal of Investigative Dermatology examined thymosin beta 4 in experimental wound models and reported accelerated closure in the animal systems used. Subsequent reviews have examined binding modes and downstream biological consequences across a wider set of experimental contexts.
Integrated Mechanistic Profile
Recurring themes across the published literature include:
- Sequestration of monomeric actin and regulation of filament dynamics
- Influence on directional cell migration in endothelial models
- Involvement in angiogenic and tissue response signaling
An important interpretive caution applies to this compound in particular. A substantial portion of the literature examines the full length thymosin beta 4 protein rather than the seven residue fragment sold as TB-500. Findings from the parent protein should not be assumed to transfer to the fragment without direct evidence.
Note: TB-500 is supplied strictly for research use only. It is intended as an experimental compound for qualified laboratory personnel and is not a drug, food or cosmetic.
TB-500 is supplied exclusively for laboratory research use and is not intended for human or veterinary application.
Research Applications (Observations from Studies)
The following describes areas of published investigation and does not constitute any claim regarding outcomes outside those experimental contexts.
Cytoskeletal and Cell Motility Models
The most direct application involves in vitro systems examining actin polymerisation state and cellular motility, where the actin binding property can be assessed against measurable endpoints.
Endothelial and Vascular Research
Endothelial cell models have been used to examine migration and vessel formation dynamics, connecting cytoskeletal mechanism to angiogenic research questions.
Tissue Response and Repair Models
Animal models examining structural response following induced injury represent an established area of published work for the parent protein, with investigators assessing markers of matrix organisation and cellular recruitment.
Comparative Peptide Research
TB-500 is frequently examined alongside other tissue research peptides in comparative study designs, since its cytoskeletal mechanism differs from compounds acting through nitric oxide or receptor mediated pathways.
TB-500 is supplied exclusively for laboratory research use and is not intended for human or veterinary application.
TB-500 Compared With Related Research Compounds
The table below places TB-500 alongside two related compounds in the Peptsche range. It is offered to clarify differences in classification, molecular target and research context. It should not be read as a comparison of clinical performance, safety, or suitability for any application.
| Characteristic | TB-500 | BPC-157 | Wolverine Blend |
| Research Classification | Synthetic acetylated seven residue peptide | Synthetic pentadecapeptide | Two component co lyophilized research blend |
| Primary Molecular Target | Monomeric G actin within the cytoskeleton | Nitric oxide and angiogenic signaling pathways | Nitric oxide signaling and monomeric G actin, addressed by separate components |
| Mechanistic Profile | Actin sequestration and cytoskeletal reorganisation | Pleiotropic activity across several signaling systems | Two unrelated pathways, combination not studied in published work |
| Primary Research Focus | Cell migration and endothelial models | Tissue integrity, vascular and mucosal models | Vascular and cytoskeletal research in one preparation |
| Structural Design | Seven residues, N terminal acetyl group, free acid C terminus | Fifteen residues, no unnatural residues or modification | Mixture of two peptides, no single formula or CAS number |
| Regulatory Status | Research use compound, not approved for human or veterinary use, and listed by the United States Food and Drug Administration among bulk drug substances withdrawn from consideration for compounding | Research use compound, not approved for human or veterinary use | Research use blend, neither component approved for human or veterinary use, and the TB-500 component appears on the United States Food and Drug Administration list of bulk drug substances withdrawn from consideration for compounding |
TB-500 is supplied exclusively for laboratory research use and is not intended for human or veterinary application.
Laboratory Handling and Storage Considerations
TB-500 should be handled in accordance with institutional laboratory procedures and established practice for research peptides. Maintain storage conditions consistent with product documentation, keeping vials sealed and protected from heat, light and moisture. Record lot numbers, storage conditions and preparation methods in laboratory documentation, and retain certificates of analysis alongside study records to support reproducibility.
Laboratory Safety Considerations
TB-500 should be handled in the same manner as other research compounds without a fully characterised toxicological profile.
- Personal protective equipment: Use appropriate PPE including laboratory coat, nitrile gloves and eye protection.
- Engineering controls: Minimise generation of aerosols or dust. Conduct weighing and transfer procedures using suitable containment.
- Exposure prevention: Avoid inhalation, ingestion and contact with skin or eyes. Do not taste or smell the material. Wash hands thoroughly after handling.
- Storage: Keep containers tightly sealed and protected from light and moisture under the conditions specified.
- Spill response: Address spills using appropriate PPE and institutional spill response procedures. Avoid dry sweeping.
- Disposal: Dispose of unused material, consumables and waste in accordance with local regulations and institutional programmes.
- Documentation: Maintain all lot and handling records. Additional handling guidance is available on request.
Certificate of Analysis and Quality Assurance
Every production lot of TB-500 supplied by Peptsche undergoes analytical evaluation, and a batch specific Certificate of Analysis accompanies each order to support research documentation, quality control and experimental consistency.
Each Certificate of Analysis typically includes:
- Identity verification using analytical techniques such as mass spectrometry to confirm the molecular characteristics of the material supplied.
- Purity analysis performed by high performance liquid chromatography to quantify purity and identify potential impurities.
- Batch documentation recording lot number, testing date, analytical methods applied and quality assessment results.
- Traceability information to support laboratory recordkeeping and reproducibility across research workflows.
Peptsche works with Janoshik Analytical, an independent testing laboratory, for third party verification of research material quality. Independent testing provides transparency and confidence in product identity, consistency and sourcing, and batch specific documentation can be retained as part of laboratory records and internal quality procedures.
TB-500 is supplied exclusively for laboratory research use and is not intended for human or veterinary application.
Frequently Asked Questions
What is TB-500?
TB-500 is a short synthetic peptide of seven amino acid residues, acetylated at the N terminus, whose sequence reproduces the actin binding domain of thymosin beta 4. Peptsche supplies it as a lyophilized powder of high analytical purity, sealed in a glass vial for controlled laboratory investigation.
What is TB-500 studied for in research?
Published investigation is preclinical and spans cytoskeletal and cell motility models, endothelial and vascular research, tissue response models and comparative peptide study designs. A substantial portion of that literature examines the full length thymosin beta 4 protein rather than the seven residue fragment, so findings should not be assumed to transfer without direct evidence.
How does TB-500 work in laboratory research?
TB-500 is studied primarily in terms of intracellular protein interaction rather than activity at a defined cell surface receptor. The retained actin binding motif is the structural basis for research interest, with recurring themes covering sequestration of monomeric actin, influence on directional cell migration in endothelial models and involvement in angiogenic and tissue response signaling.
How is the quality of Peptsche TB-500 verified?
Every production lot of Peptsche TB-500 is evaluated analytically, with identity confirmed using techniques such as mass spectrometry and purity quantified by high performance liquid chromatography. Peptsche works with Janoshik Analytical, an independent testing laboratory, for third party verification, and a batch specific Certificate of Analysis accompanies each order.
How should unopened TB-500 be stored?
Unopened vials should be stored sealed at 2 to 8 °C, protected from heat, light and moisture. Vials should reach ambient temperature before opening, and lot number, storage conditions and preparation date should be recorded in laboratory documentation so results stay traceable to a batch.
Is TB-500 intended for human use?
No. TB-500 is supplied strictly for laboratory research use only. It is not approved for human consumption, veterinary use, diagnosis, treatment or any medical application.
Why do researchers choose Peptsche for TB-500?
Peptsche supplies TB-500 at 99% or greater purity by HPLC, verified per batch, in a sealed glass vial with batch specific analytical documentation. Independent third party verification and full lot traceability support reproducibility across research workflows.
Scientific References
- Malinda KM, Sidhu GS, Mani H, Banaudha K, Maheshwari RK, Goldstein AL, Kleinman HK. Thymosin beta4 accelerates wound healing. Journal of Investigative Dermatology. 1999;113(3):364 to 368. https://pubmed.ncbi.nlm.nih.gov/10469335/
- Malinda KM, Goldstein AL, Kleinman HK. Thymosin beta 4 stimulates directional migration of human umbilical vein endothelial cells. FASEB Journal. 1997;11(6):474 to 481. https://pubmed.ncbi.nlm.nih.gov/9194528/
- Ying Y, Lin C, Tao N, Hoffman RD, Shi D, Chen Z, Gao J. Thymosin beta 4 and Actin: Binding Modes, Biological Functions and Clinical Applications. Current Protein and Peptide Science. 2023;24(1):78 to 88. https://pubmed.ncbi.nlm.nih.gov/36464872/
RESEARCH USE ONLY
These compounds are NOT intended for human consumption, clinical use, or veterinary applications. We are not affiliated with any pharmaceutical companies or their commercial medications. By placing an order, you certify these materials will be used exclusively for in vitro testing and laboratory experimentation only. Bodily introduction of any kind into humans or animals is strictly forbidden by law. This product should only be handled by licensed, qualified professionals. This product is not a drug, food, or cosmetic and may not be misbranded, misused or mislabeled as a drug, food or cosmetic.