TB-500

TB-500 is the synthetic form of the active region of Thymosin Beta-4 (Tβ4), a ubiquitously expressed 43-amino-acid peptide found in virtually all nucleated cells of the human body. Native Tβ4 was first identified in 1966 by Allan Goldstein at Albert Einstein College of Medicine and isolated from the thymus. TB-500 contains the central active sequence LKKTETQ (amino acids 17–23), which is essential for biological activity. The central mechanism of action is based on the sequestration of actin G-monomers and regulation of actin polymerization, promoting cell migration and proliferation in damaged tissue. By binding actin monomers at a 1:1 ratio, TB-500 prevents uncontrolled polymerization while simultaneously creating an intracellular reservoir that can be mobilized on demand for directed cell movement. Studies by Goldstein et al. (Annals of the New York Academy of Sciences, 2007) and Philp et al. (International Wound Journal, 2012) document the role of Tβ4 in wound healing, cardiac regeneration and neuroprotection. The peptide also regulates expression of laminin-5 and matrix metalloproteinases (MMP-2, MMP-9), supporting tissue remodeling and extracellular matrix reorganization. Phase II clinical trials for the treatment of epidermal wounds (Treadwell et al., Annals of the New York Academy of Sciences, 2012) and diabetic ulcers show accelerated healing rates with wound closure of 62% vs. 38% placebo after 28 days. In cardiac research, work by Hinkel et al. (Journal of the American Heart Association, 2015) shows that Tβ4 after ischemia-reperfusion reduces infarct size by 40% in the mouse model and stimulates epicardial progenitor cell activation.