TB-500 Capsules

Identity

TB-500 is a synthetic peptide corresponding to the actin-binding region of thymosin beta-4, built around the LKKTETQ motif at residues 17-23 of the parent protein.

Molecular target

No cell-surface receptor. The motif binds monomeric G-actin directly, forming a one-to-one complex, so the target is a cytoskeletal protein rather than a membrane receptor.

Signalling pathway

Sequestering G-actin shifts the monomeric-to-filamentous actin equilibrium, with downstream effects on cytoskeletal reorganisation, directed cell migration and MRTF/SRF-dependent transcription.

Research context

The open question specific to this format is oral bioavailability. TB-500 is substantially larger than the small molecules in this range, and peptides of this size are generally poorly absorbed intact through the gastrointestinal tract. That makes the capsule format itself a subject of study rather than a settled delivery route, and it should be treated as such in any protocol design.

Specification

• Form: capsules, 60 per sealed bottle
• Content: 500 mcg per capsule
• Purity: verified by high-performance liquid chromatography with mass spectrometric confirmation
• Storage: cool, dry, away from direct light

For laboratory research use only. Not for human or veterinary use.