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The library now covers 173 peptides. Browse it

Library · Immune · Immune regulation, research compound.

Thymulin (Thymic Factor)

Serum Thymic Factor, STF, Facteur Thymique Serique, FTS, Thymic Factor

A naturally occurring nonapeptide from thymus epithelial cells, active only when bound to zinc, that regulates T-cell development, NK-cell activity, and cytokine production, with possible influence on stress-related hormone regulation. It remains a research compound, not FDA-approved as a drug, though a related thymus-tissue product is approved for congenital athymia.

Research score 70/100. Reference only, not a dose.

  • Immune Boosting
  • Anti-inflammatory
  • Anti-aging
  • Hormone Regulation
  • Inflammation Resolution
US status
Research Chemical
Approval
Not FDA approved as a drug. Rethymic (related product) approved for congenital athymia (2021).
Evidence
Limited Human Studies
Research score
70 / 100
Indication
Immune Deficiency
Origin
France
Source category
Immune System
Status group
Research chemical

Mechanism

Requires zinc binding for activity; engages JAK/STAT and MAPK pathways in T-cells to raise T-cell marker expression and output of interleukins and interferon-gamma, supporting both cellular and antibody immunity, plus anti-inflammatory effects via reduced NF-κB signaling.

Safety file

Generally well tolerated in research and clinical use, with occasional fatigue or mild injection-site irritation; not advised for those with thymus disorders or active autoimmune flares without supervision.

  • Injection site reactions
  • Mild fatigue
  • Slight injection site irritation
  • Temporary immune system fluctuations