Thymosin Alpha-1 is a component of Thymosin Fraction 5 responsible for restoring immune function in animals lacking thymus glands. It was the original peptide synthesized from the Thymosin Fraction 5. Unlike β thymosins, which are genetically and chemically unrelated, Thymosin α1 is produced as a 28-amino acid peptide fragment from a longer, 113-amino acid precursor,prothymosin alpha. Research has shown it to enhance cell-mediated immunity in experimental animals and research subjects.Thymosin Alpha-1 is being researched for the treatment of Hepatitis B and C, and it is also approved for inclusion with vaccines to boost the immune response in the treatment of other diseases.