TB-500 is a synthetic variant of the naturally occurring peptide found in nearly all human and animal cells, known as Thymosin Beta 4 (TB-500). It is a first-in-class drug candidate that facilitates the following: differentiation of endothelial (blood vessel) cells; angiogenesis (the formation of new blood vessels from pre-existing ones) in dermal tissues; migration of keratinocytes; deposition of collagen; and reduction of inflammation.
One of the primary mechanisms of TB-500 is its capability to regulate actin, a crucial protein involved in cell structure and motility. Among the myriad proteins in cells, actin constitutes up to 10% of the total proteins, thus playing a significant role in the cell's genetic composition.
This powerful peptide is part of a widespread family of 16 related molecules that show high sequence and localization similarity across most tissues and circulating cells in the body. TB-500 not only interacts with actin, but also inhibits actin polymerization and serves as the actin-sequestering molecule in eukaryotic cells.
TB-500 was identified as a gene whose expression increased four to six times during the early stages of blood vessel formation and is known to stimulate the creation of new blood cells from existing vessels. This peptide is found in wound fluid and, when administered subcutaneously, aids in wound healing, promotes muscle growth, and accelerates recovery time for muscle fibers and cells.
Another significant aspect of TB-500 is its facilitation of cell migration through a specific interaction with actin within the cell cytoskeleton. Evidence has shown that a central, small amino acid length actin-binding domain exhibits characteristics for both blood cell reproduction and wound healing. These features are revealed through the enhanced migration of endothelial cells and keratinocytes and the increase in extracellular matrix-degrading enzymes.
Research indicates that TB-500 is a powerful, naturally occurring wound repair factor possessing anti-inflammatory properties. Unlike other repair factors, such as growth factors, TB-500 promotes the migration of endothelial and keratinocyte cells. It does not attach to the extracellular matrix and has a very low molecular weight, allowing it to travel relatively long distances within tissues.