A 28-amino-acid peptide originally isolated from thymic tissue (thymosin fraction 5) by Allan Goldstein in 1977. Thymosin alpha-1 (Tα1) is a bidirectional immune modulator — it upregulates immune response in immunodeficiency while dampening excessive inflammation in sepsis and autoimmunity. Activates dendritic cells via TLR2 and TLR9, enhances NK cell cytotoxicity, and promotes T-cell maturation. Approved in over 35 countries (trade name Zadaxin) for hepatitis B and as an immune adjuvant.
TargetsTLR2/TLR9, dendritic cells, NK cells, T-cell maturation
Research FocusImmune modulation, viral hepatitis, vaccine adjuvancy, sepsis, cancer immunotherapy
ReconstitutionBacteriostatic water — 1.6 mg/mL
Stability21 days at 2–8°C
Key distinction: Bidirectional immune modulator — uniquely capable of both upregulating suppressed immunity and dampening hyperinflammation. Approved in 35+ countries with decades of clinical safety data.
Scientific Evidence
Published Research
[1]
Goldstein AL et al. Thymosin alpha1: isolation and sequence analysis of an immunologically active thymic polypeptide. Proc Natl Acad Sci USA 1977;74:725-729 — PubMed 265542
[2]
Romani L et al. Thymosin alpha1 activates dendritic cell tryptophan catabolism and establishes a regulatory environment for balance of inflammation and tolerance. Blood 2006;108:2265-2274 — PubMed 16740584
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