TB-500

What is TB-500?

TB-500 refers to synthetic fragments of thymosin beta-4, a 43-amino-acid peptide naturally present in nearly all human and animal cells. Thymosin beta-4 is best known as the major intracellular G-actin sequestering peptide. Research interest in TB-500 stems from preclinical observations of its effects on cell migration, angiogenesis, and tissue regeneration in animal injury models.

Mechanism of action (preclinical evidence)

Thymosin beta-4 binds monomeric (G-) actin, regulating actin polymerisation and cytoskeletal dynamics. In injury models it has been associated with up-regulation of laminin-1, increased angiogenesis via the VEGF axis, and modulation of inflammatory mediator release. Published work links these mechanisms to observed effects on wound closure, dermal regeneration, and cardiac repair in animals.

Research applications

• Cutaneous wound healing models (full-thickness skin injury)
• Cardiac infarct repair (rodent ischaemia-reperfusion)
• Corneal epithelial repair studies
• Muscle regeneration in dystrophic models
• Investigation of cell migration and angiogenesis

Storage and handling

Lyophilised TB-500 should be stored at -20 °C, protected from light. Reconstituted solutions are generally less stable — handle in single-use aliquots when possible and follow your laboratory's freeze-thaw protocols.

Regulatory status

TB-500 is not approved for human use by any regulator. The natural full-length thymosin beta-4 has been investigated as Tβ4 in some clinical studies for ophthalmic indications, but the synthetic fragments commonly sold as 'TB-500' have a separate research profile. WADA prohibits TB-500 in sport (S0).