Tuftsin
Also known as: TKPR tetrapeptide
Tuftsin, a tetrapeptide cleaved from the Fc region of IgG, binds the receptor neuropilin-1 and signals through the transforming growth factor beta pathway to stimulate phagocytosis and related innate immune cell functions.
- Drug class
- Immunomodulatory phagocytosis-stimulating tetrapeptide
- Primary targets
- Neuropilin-1 (Nrp1), TGF-beta receptor-1, Macrophages, Neutrophils, Microglia
- Dose reference
- No approved or established human dose; used at nanomolar concentrations in vitro and by injection in animal and small early-phase human research only (not a recommendation).
- Half-life
- Very short; the native tetrapeptide is rapidly degraded by aminopeptidases (minutes or less).
- Developer / origin
- Victor Najjar and colleagues, Tufts University
- Reference year
- 1970
- Evidence score
- 2/5 - Preclinical / mechanistic
Preclinical / mechanistic
Tuftsin has a deep mechanistic and preclinical literature, including a defined neuropilin-1/TGF-beta signaling pathway and a recognized deficiency syndrome, but no regulator-approved indication and no large modern controlled human trials establishing a safe, effective dose.
Mostly animal, ex vivo, cell, or indirect evidence.
Evidence basis
- Receptor and signaling pathway (Nrp1/TGF-beta) characterized in peer-reviewed work
- Tuftsin deficiency documented in splenectomized and congenital cases (OMIM)
- Antitumor, anti-infective and neuroinflammation effects shown mainly in cell and animal models
- No FDA approval, no DailyMed label, no established human dosing
- Most developed applications use engineered analogs (e.g., Selank) or fusion proteins rather than the free peptide
Key references
How to read this entry
Dose references and half-life values are pulled from trial protocols, labels, reviews, or published summaries where available. They are context for research and comparison, not a personal dosing recommendation.
Status matters: approved drugs have regulated indications; investigational compounds are still being studied; research-only peptides do not have established human dosing, safety, or efficacy for consumer use.
Tuftsin guides
Read the matching guide or adjacent research pages for more context.
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