TB-500 10mg

Research overview

TB‑500 (the synthetic form of thymosin β‑4, Tβ4) is a 43‑amino‑acid peptide with an N‑terminal acetylation and a critical LKKTETQ actin‑binding motif at positions 17–23. It belongs to the highly conserved β‑thymosin family (16 isomers) and is one of the most abundant intracellular peptides in mammalian cells. TB‑500 is prepared by solid‑phase peptide synthesis and functions as a G‑actin‑sequestering protein. TB‑500 plays a central role in preclinical studies of cytoskeletal biology and tissue remodeling. Its primary mechanism involves sequestering monomeric globular actin, thereby regulating the balance between G‑actin monomers and polymerized filamentous actin—a balance that governs cell migration, morphogenesis, and cytoskeletal reorganization. The conserved LKKTET motif is critical for actin binding; however, mutagenesis studies indicate that this motif alone exhibits weak G‑actin affinity, and that high‑affinity sequestration depends on additional contacts from flanking regions within the full‑length peptide. In vitro studies in endothelial cells, fibroblasts, and keratinocytes have documented enhanced endothelial differentiation, basement‑membrane‑like capillary formation, and directed cell migration, as well as extracellular matrix remodeling mediated by matrix metalloproteinases. In vivo rodent studies in skin wound, corneal injury, and cardiac ischemia models have reported accelerated full‑thickness skin wound closure, accompanied by increased angiogenesis and collagen deposition. Collectively, these findings span the cascade of tissue remodeling—from neovascularization and collagen deposition through the inflammatory‑to‑proliferative transition.