What it is
Thymosin alpha-1 is a peptide made of 28 amino acids. The body makes it naturally, and it is also made in a lab. It was first found in the thymus, the gland where T cells mature. The body makes it by cutting a larger protein called prothymosin alpha. The lab-made version is called thymalfasin and is sold as Zadaxin. It is not related to thymosin beta-4, the protein TB-500 comes from. Other names: Tα1, TA1, Thymalfasin, Zadaxin.
What researchers study it for
- Dendritic cell activation
- T cell responses
- Chronic hepatitis B and C
- Severe infection in hospital patients
- Immune tolerance
What the studies found
1. It switched on dendritic cells through toll-like receptors.
Toll-like receptors are proteins that detect parts of germs. This 2004 study found thymosin alpha-1 turned on dendritic cells through two of them, TLR2 and TLR9. The activated cells pushed T cells toward a Th1 response. Th1 is the type of response that fights viruses and fungi. Lab cells and mice.
2. It also turned on an enzyme that calms the immune system.
This 2007 review describes a second action. Thymosin alpha-1 made dendritic cells produce an enzyme called IDO. IDO breaks down tryptophan, an amino acid, and this lowers immune activity. So the same peptide can raise immune defense and also limit it. Based on cell and animal studies.
3. Hepatitis B virus dropped, but only a year after treatment ended.
A 2001 review combined 5 trials with 353 patients who had chronic hepatitis B. At the end of treatment and 6 months later, there was no difference from the control group. At 12 months after treatment ended, patients on thymosin had better odds of clearing the virus. Liver enzyme levels did not differ at any time point. The trials were small.
4. In severe sepsis, fewer treated patients died. The result was borderline.
Sepsis is a severe body-wide reaction to infection. A 2013 trial in 6 Chinese hospitals enrolled 361 patients with severe sepsis. Within 28 days, 26.0 percent of treated patients died, compared to 35.0 percent in the control group. That difference sat right at the edge of what researchers count as a real result. Human data.
How much research exists
Many human trials, mostly in China and Italy. It is approved in more than 35 countries. Many of the trials are small. It has not been approved in the United States.
Facts
- Formula: C129H215N33O55
- Weight: 3108.3 g/mol
- CAS number: 62304-98-7
- Sequence: Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN
- Time in the blood: about 2 hours after a shot under the skin
- Storage: keep the dry powder in the fridge. Keep mixed solution in the fridge.
Legal status
Approved as Zadaxin in more than 35 countries, including China and Italy, for hepatitis B, hepatitis C, and immune support. Not approved by the FDA for human use.
For research use only. Not for human use. Nothing here is medical advice.