TB-500 (Thymosin Beta-4) TB-500 is a synthetic version of the naturally occurring peptide present in virtually all human and animal cells, Thymosin Beta-4. This potent peptide is a member of a ubiquitous family of 16 related molecules with a high conservation of sequence and localization in most tissues and circulating cells in the body. TB-500 not only binds to actin, but also blocks actin polymerization and is the actin-sequestering molecule in eukaryotic cells.
