Actin-associated region
The LKKTETQ sequence corresponds to a thymosin beta-4 region associated with actin binding and cytoskeletal organization.
P—06 • Preclinical research profile
TB-500
A concise educational overview of a synthetic thymosin beta-4 fragment studied in preclinical models of wound response and cytoskeletal biology.
Name
TB-500
Sequence: LKKTETQ
- Scientific classification
- Synthetic thymosin beta-4-derived seven-amino-acid peptide fragment
- Library family
- Regenerative
- Research status
- Preclinical; published fragment-specific evidence is limited
- Regulatory status
- Not FDA approved; identified by FDA as a Category 2 compounding substance with potential significant safety risks
Compound overview
A short peptide fragment related to—but distinct from—thymosin beta-4.
TB-500 is a seven-amino-acid synthetic fragment corresponding to an actin-binding region of the naturally occurring 43-amino-acid protein thymosin beta-4.
Although TB-500 and full-length thymosin beta-4 are related, they are different molecules. Research findings involving the complete protein cannot automatically be attributed to the shorter TB-500 fragment.
Mechanism under study
Actin-associated biology and experimental wound response
The mechanism of the isolated fragment has not been established in humans. Preclinical research provides a basis for studying actin-associated cell movement and wound response, while broader effects reported for full-length thymosin beta-4 cannot be assumed for TB-500.
Cell migration
Actin dynamics participate in cellular movement during experimental tissue-repair processes.
Wound response
A mouse study reported that the LKKTETQ fragment promoted dermal repair in aged animals.
Angiogenic, anti-inflammatory, cardiac, and broad tissue-repair findings involving full-length thymosin beta-4 are not established effects of TB-500.
Current research areas
Questions under investigation
- Dermal wound repair
- Cell migration and cytoskeletal organization
- Re-epithelialization and collagen deposition
- Differences between TB-500 and full-length thymosin beta-4
- Immunogenicity, product characterization, and human safety
Evidence summary
Fragment-specific experimental findings
- Experimental wound repair: The LKKTETQ fragment promoted dermal repair in an aged-mouse model.
- Tissue-remodeling endpoints: Preclinical research has examined wound contraction, keratinocyte migration, and collagen deposition.
- Cell-migration biology: Its relationship to an actin-binding region provides a scientific basis for studying cytoskeletal movement and repair responses.
- Clinical translation: The fragment-specific findings support continued research into muscle, tendon, ligament, and systemic recovery outcomes.
Fragment-specific evidence helps distinguish TB-500 research from the broader biology reported for full-length thymosin beta-4.
Educational notice
Education, not usage guidance.
This profile is provided for scientific education only. It is not medical advice, treatment guidance, dosing information, or instructions for TB-500 use. The FDA has identified potential concerns involving aggregation, immunogenicity, peptide-related impurities, and the absence of adequate human exposure and safety information.
Key scientific referencesComing soon
A curated primary-source reference list will be added during the next educational expansion.