Tuftsin
Tuftsin is an endogenous immunostimulatory tetrapeptide in the Immune Modulator class. Tuftsin is released by enzymatic cleavage of the IgG heavy chain and binds receptors on neutrophils, monocytes and macrophages, where it has been reported to stimulate phagocytosis, chemotaxis and antigen presentation.
For research use only.
Key Facts
- CAS
- —
- Molecular Weight (MW)
- 500.6 g/mol
- Half-life
- —
- FDA status
- Not Approved
- Administration Route
- subcutaneous
- Frequency
- —
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
Research summary
Naturally occurring tetrapeptide derived from the Fc region of immunoglobulin G, studied for effects on phagocytes. It is the structural parent of Selank. Not FDA-approved.
Peptide Library's Tuftsin profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Protocol
- Dosage Range
- —
- Frequency
- —
- Cycle
- —
- Administration Route
- subcutaneous
- Reconstitution Guide
- —
Sequence & molecular data
| Amino acid sequence | Thr-Lys-Pro-Arg |
|---|---|
| Molecular formula | C21H40N8O6 |
| Molecular weight | 500.6 g/mol |
| PubChem CID | 156080 |
| FDA UNII | QF5336J16C |
| ChEMBL | CHEMBL4563222 |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Tuftsin is released by enzymatic cleavage of the IgG heavy chain and binds receptors on neutrophils, monocytes and macrophages, where it has been reported to stimulate phagocytosis, chemotaxis and antigen presentation. Its very short plasma half-life is the main obstacle to therapeutic use and the reason stabilised analogs such as Selank were developed.
Studies
- Helminth derivative tuftsin-phopshorylcholine to treat autoimmunity
- Tuftsin phosphorylcholine-a novel compound harnessing helminths to fight autoimmunity
- Tuftsin - Properties and Analogs
- FcγR-targeted tuftsin clusters rejuvenate macrophages in preclinical sepsis-associated secondary infection
- The P2X7-Mediated Mitochondrial ROS as an Emerging Core Target of Tuftsin Nanoparticles in Severe Acute Pancreatitis Therapy via Regulating Mitophagy
Regulatory & research status
Tuftsin is not an FDA-approved product. It is sold for laboratory research and has no approved medical use.
| FDA status | Not Approved |
|---|---|
| Research status | Research-only compound; no approval pathway listed |
| Availability | Research-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | Research-Only |
Benefits
—
Potential Side Effects
No side effects listed yet for this entry.
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Tuftsin: frequently asked questions
What is Tuftsin?
Naturally occurring tetrapeptide derived from the Fc region of immunoglobulin G, studied for effects on phagocytes. It is the structural parent of Selank. Not FDA-approved.
How does Tuftsin work?
Tuftsin is released by enzymatic cleavage of the IgG heavy chain and binds receptors on neutrophils, monocytes and macrophages, where it has been reported to stimulate phagocytosis, chemotaxis and antigen presentation. Its very short plasma half-life is the main obstacle to therapeutic use and the reason stabilised analogs such as Selank were developed.
Is Tuftsin FDA approved?
No. Tuftsin is not approved by the FDA for any indication and is categorised as research-only. It has not been reviewed for safety or efficacy as a medicine, and published research should be read as investigation rather than established use.
What is the amino acid sequence of Tuftsin?
Tuftsin has the sequence Thr-Lys-Pro-Arg, giving a chain of 4 amino acids. Its molecular formula is C21H40N8O6.
What peptides are similar to Tuftsin?
Compounds most often compared with Tuftsin include Selank, N-Acetyl Selank Amidate, Semax and Noopept. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- Helminth derivative tuftsin-phopshorylcholine to treat autoimmunity — Autoimmun Rev, 2024External reference
- Tuftsin phosphorylcholine-a novel compound harnessing helminths to fight autoimmunity — Immunol Res, 2018External reference
- Tuftsin - Properties and Analogs — Curr Med Chem, 2017External reference
- FcγR-targeted tuftsin clusters rejuvenate macrophages in preclinical sepsis-associated secondary infection — Sci Transl Med, 2025External reference
- The P2X7-Mediated Mitochondrial ROS as an Emerging Core Target of Tuftsin Nanoparticles in Severe Acute Pancreatitis Therapy via Regulating Mitophagy — ACS Appl Mater Interfaces, 2025External reference
Related research, comparisons & guides
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Tuftsin profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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