Tuftsin / Studies

Natural fragment · 4 amino acids · 500.6 Da

Tuftsin studies and research data

PepBank has no study results for Tuftsin yet. Data as of 2026-10-30.

Searches 0 results and 0 papers. Newer studies from Europe PMC

Results in people

0% of 0 results

Results in animals

0% of 0 results

Results in lab cells

0% of 0 results

From computer models

0% of 0 results

The molecule

Tuftsin identity

Identifiers, parent molecule, targets and development stage, from curated data.

Tuftsin is the tetrapeptide H-Thr-Lys-Pro-Arg-OH, located at residues 289-292 of the IgG heavy chain CH2 domain and described in 1970 as a natural phagocytosis-stimulating peptide. Later studies report that it binds neuropilin-1 and, in microglia, signals through the TGF-beta pathway. It is the parent sequence of Selank.

Kind: Natural fragment · 4 residues
Identifiers: UniProtP01857 (opens in a new tab)ChEMBLCHEMBL4563222 (opens in a new tab)PubChem CID156080 (opens in a new tab)UNIIQF5336J16C (opens in a new tab)CAS9063-57-4PDB2ORZ (opens in a new tab)
Parent: Fragment of Immunoglobulin heavy constant gamma 1 (IgG1 heavy chain constant region) · residues 172-175Naim et al. 1989 (PMID 2475442): 'Tuftsin is located in the FC region of IgG between the 289 and 292 amino acid sequence of the CH2 domain.' Lukas et al. 1981 (PMID 7299136) studied peptides containing residues 289-292 or 282-292 of the second constant domain of human IgG1; its abstract does not use the word tuftsin. UniProt position 172-175 is an exact match of TKPR in P01857 (the only occurrence); EU numbering 289-292 minus the 117-residue offset of the UniProt entry gives 172-175.
Development: No known clinical developmentNo studies on ClinicalTrials.gov (queries with and without synonym expansion and a free-text search, 2026-10-09). ChEMBL gives no phase. Discovered by Najjar and Nishioka 1970 (PMID 4097539). Source (opens in a new tab)

Targets

Molecular targets with action and evidence source
Target	Action	Evidence
Neuropilin-1NRP1O14786 (opens in a new tab)	Binds (ligand)	primary literatureSource (opens in a new tab)

Sequence and structure

Residues, differences from the parent, calculated properties and 3D structure. Source values and calculated values are shown separately.

Sequence

4 amino acids

H-

TKPR

-OH

Parent: Immunoglobulin heavy constant gamma 1 (IgG1 heavy chain constant region)

No sequence is listed for the parent, so no alignment is shown.Naim et al. 1989 (PMID 2475442): 'Tuftsin is located in the FC region of IgG between the 289 and 292 amino acid sequence of the CH2 domain.' Lukas et al. 1981 (PMID 7299136) studied peptides containing residues 289-292 or 282-292 of the second constant domain of human IgG1; its abstract does not use the word tuftsin. UniProt position 172-175 is an exact match of TKPR in P01857 (the only occurrence); EU numbering 289-292 minus the 117-residue offset of the UniProt entry gives 172-175.

Properties

From identity sources

Formula: C₂₁H₄₀N₈O₆
Molecular weight: 500.6 g/mol
Monoisotopic mass: 500.3071 Da

GSRS UNII QF5336J16C(opens in a new tab)retrieved 2026-10-08
PubChem CID 156080(opens in a new tab)retrieved 2026-10-08
ChEMBL CHEMBL4563222(opens in a new tab)retrieved 2026-10-08
UniProt P01857(opens in a new tab)retrieved 2026-10-08

Calculated from the sequence

pKa set

Average mass: 500.60 Da; Sum of ExPASy residue masses + water · ExPASy Compute pI/Mw; FindMod
Monoisotopic mass: 500.3071 Da; Sum of ExPASy residue masses + water · ExPASy FindMod
Isoelectric point (pI): 11.65; pH of zero net charge, EMBOSS pKa set · EMBOSS iep, Epk.dat
Net charge at pH 7.4: 1.94; Henderson-Hasselbalch, EMBOSS pKa set · EMBOSS iep, Epk.dat
GRAVY (hydropathy): −2.675; Mean Kyte-Doolittle hydropathy · Kyte and Doolittle 1982; Negative: hydrophilic on average.
Extinction coefficient, 280 nm (Cys reduced): 0 M⁻¹ cm⁻¹; 5500 x Trp + 1490 x Tyr · Pace et al. 1995 (ExPASy ProtParam); No Trp or Tyr: absorbance at 280 nm cannot measure this peptide.
Instability index: −30.20; Dipeptide instability weights (DIWV) · Guruprasad et al. 1990; 40 or below: classed as stable (ExPASy).
Aliphatic index: 0.0; Mole % A + 2.9 V + 3.9 (I + L) · Ikai 1980
Boman index: 5.76 kcal/mol; Mean solubility value (negated) · Boman 2003; Above 2.48: high protein-binding potential (Boman).
Hydrophobic moment (μH): Not calculated; The sequence is too short for this method.
pI with each pKa set: EMBOSS 11.65Bjellqvist (ExPASy) 11.00IPC peptide 11.54IPC protein 10.61

Defined and validated for proteins; use with care for short peptides.
Assumes an ideal alpha helix. Many short peptides are not helical.

@pepdb/chem 0.2.0 · EMBOSS pKa set · ExPASy residue masses

Net charge by pH

pI 11.65 · Net charge at pH 7.4: 1.94

Point or use arrow keys

Henderson-Hasselbalch, EMBOSS pKa set. Calculated, not measured.

Show as table

pH	Net charge
0	3.00
1	3.00
2	2.98
3	2.80
4	2.28
5	2.04
6	2.00
7	1.98
8	1.80
9	1.27
10	0.90
11	0.36
12	−0.18
13	−0.75
14	−0.97

Composition

Positive50% (2)K R
Polar25% (1)T
Special25% (1)P

4 residues. Each residue counts in one class; F and W count as aromatic.

A Ala0 · 0%

I Ile0 · 0%

L Leu0 · 0%

M Met0 · 0%

V Val0 · 0%

F Phe0 · 0%

W Trp0 · 0%

Y Tyr0 · 0%

H His0 · 0%

K Lys1 · 25%

R Arg1 · 25%

D Asp0 · 0%

E Glu0 · 0%

N Asn0 · 0%

Q Gln0 · 0%

S Ser0 · 0%

T Thr1 · 25%

C Cys0 · 0%

G Gly0 · 0%

P Pro1 · 25%

3D structure

ExperimentalPDB 2ORZ

Loads the 3D viewer (3Dmol.js, about 150 KB) and the model file from RCSB PDB.

2D structure

Draws the structure in your browser with RDKit (about 2.3 MB, loaded once).

SMILES fromPubChem CID 156080(opens in a new tab)

C[C@H]([C@@H](C(=O)N[C@@H](CCCCN)C(=O)N1CCC[C@H]1C(=O)N[C@@H](CCCN=C(N)N)C(=O)O)N)O

Results by area

Tuftsin results by year and outcome

Counts are exact and come from studies that gave the peptide.

Studies by year

No study has results about Tuftsin yet.

No study with a publication year is linked to this peptide.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

What the studies measured

People first in each area, then animals, then lab cells. Counts are exact and come from studies that gave the peptide.

No study of Tuftsin has results in PepBank yet.

Trials and papers

Tuftsin trials

Registered trials that test the peptide, with phase, status and dates. A dot marks trials with posted results.

StatusPhase

0 trials match. Highest phase first. Data from ClinicalTrials.gov.

No trial matches these filters.

Papers

Studies on this peptide. Some have results. The others have none yet.

Sort

Design

0 studies match. Retracted studies are left out.

No study matches these filters.

Newer studies

PepBank reads each paper before it shows the results. This search looks in Europe PMC for newer papers that PepBank has not read yet.

Tuftsin studies: 0 papers with results

No paper with results is linked to this peptide.

Status and safety

Regulatory and safety

Approval and sport status, and the safety outcomes reported in study results. Laws and labels change, so check the regulator for the current status.

Regulatory status by jurisdiction, with date and source
Jurisdiction	Body	Status	As of	Source
US	FDA	No Drugs@FDA application found (openFDA search 'tuftsin').	9 Oct 2026	fda.gov (opens in a new tab)
EU	EMA	No centrally authorised, withdrawn or refused medicine and no orphan designation for this substance in the EMA data files (medicines file, all statuses, timestamp 2026-10-09T06:23:44Z; orphan designations file timestamp 2026-10-09T06:32:20Z). National authorisations in EU member states were not checked.	9 Oct 2026	ema.europa.eu (opens in a new tab)
Sport	WADA	Not named on the List; S0 may still apply (no approval anywhere) S0 bans any substance that has no approval for human use. Tuftsin has no approval in the sources used, so S0 may apply although the List does not name it.	2026 List	wada-ama.org (opens in a new tab)

Safety outcomes

Reported effects from study results.

No study results yet

No safety results yet. That does not mean the peptide is safe.

Doses studied

The doses that these studies used. They are not recommendations.

No dose was reported in the study results.

PepBank is a research reference. Talk to a doctor before you use any peptide.

Data

Data and API

Data version, change history and code for this peptide.

Data version 30856030 Oct 2026

Peptide

Peptide id: PEP-000042
Peptide version: 8
Peptide hash: 8422eb9dba1efd7e…
Data version: 308560

Latest changes

27 Oct 2026UpdatedData version 256796
22 Oct 2026UpdatedData version 254590
21 Oct 2026UpdatedData version 213674
14 Oct 2026UpdatedData version 194730
13 Oct 2026UpdatedData version 173571
12 Oct 2026UpdatedData version 165146

For developers

curl -s https://pepbank.io/v1/briefs/tuftsin

Evidence summary for Tuftsin: counts by class, key results with sources, notices, data version.

Peptide as JSON Evidence summary as JSON

Tuftsin studies and research data

Tuftsin identity

Targets

Sequence and structure

Sequence

Parent: Immunoglobulin heavy constant gamma 1 (IgG1 heavy chain constant region)

Properties

Net charge by pH

Composition

3D structure

2D structure

Tuftsin results by year and outcome

What the studies measured

Tuftsin trials

Papers

Newer studies

Tuftsin studies: 0 papers with results

Regulatory and safety

Doses studied

Data and API

Peptide

Latest changes

For developers

Related peptides

Tuftsin results by year and outcome

Tuftsin trials

Papers

Regulatory and safety

Doses studied

Data and API

Peptide

Latest changes

For developers