This is a working overview of Selank, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-05-07. Anything still debated is marked as such rather than presented as settled.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
Tuftsin, the parent structure, is a naturally occurring immunomodulatory tetrapeptide released from the Fc region of immunoglobulin G by spleen enzymes. Selank extends this four-residue sequence with three additional amino acids. The stated rationale is that the added tail slows enzymatic breakdown and may influence receptor interactions. How the full heptapeptide behaves at the molecular level is not firmly established, and proposed mechanisms often involve indirect modulation of neurotransmitter or immune signaling rather than a single defined target.
Selank is a synthetic heptapeptide developed in Russia. Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, a seven-residue chain built around the natural tetrapeptide tuftsin. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences first described the compound in the mid-1990s. The design combined the tuftsin core with an added Pro-Gly-Pro tail, a modification intended to extend the molecule's stability in biological fluids. Published work on the peptide has appeared mainly in Russian-language journals.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
== Production and use == Nitrilotriacetic acid is commercially available as the free acid and as the sodium salt. It is produced from ammonia, formaldehyde, and sodium cyanide or hydrogen cyanide. NTA is also cogenerated as an impurity in the synthesis of EDTA, arising from reactions of the ammonia coproduct. Older routes to NTA included alkylation of ammonia with chloroacetic acid and oxidation of triethanolamine.
===== Process ===== A large fraction of human tumor mutations are effectively patient-specific. Therefore, neoantigens may also be based on individual tumor genomes. Deep-sequencing technologies can identify mutations within the protein-coding part of the genome (the exome) and predict potential neoantigens. In mice models, for all novel protein sequences, potential MHC-binding peptides were predicted. The resulting set of potential neoantigens was used to assess T cell reactivity. Exome–based analyses were exploited in a clinical setting, to assess reactivity in patients treated by either tumor-infiltrating lymphocyte (TIL) cell therapy or checkpoint blockade. Neoantigen identification was successful for multiple experimental model systems and human malignancies. The false-negative rate of cancer exome sequencing is low—i.e.: the majority of neoantigens occur within exonic sequence with sufficient coverage. However, the vast majority of mutations within expressed genes do not produce neoantigens that are recognized by autologous T cells. As of 2015 mass spectrometry resolution is insufficient to exclude many false positives from the pool of peptides that may be presented by MHC molecules. Instead, algorithms are used to identify the most likely candidates. These algorithms consider factors such as the likelihood of proteasomal processing, transport into the endoplasmic reticulum, affinity for the relevant MHC class I alleles and gene expression or protein translation levels.
In 1600 BCE, the Edwin Smith Papyrus, an Ancient Egyptian medical text, described the heart and its vessels, as well as the brain and its meninges and cerebrospinal fluid, and the liver, spleen, kidneys, uterus and bladder. It showed the blood vessels diverging from the heart. The Ebers Papyrus (c. 1550 BCE) features a "treatise on the heart", with vessels carrying all the body's fluids to or from every member of the body. The Hellenistic Egyptian city of Alexandria was the stepping-stone for Greek anatomy and physiology. Alexandria not only housed the biggest library for medical records and books of the liberal arts in the world during the time of the Greeks but was also home to many medical practitioners and philosophers. Great patronage of the arts and sciences from the Ptolemaic dynasty of Egypt helped raise Alexandria up, further rivalling other Greek states' cultural and scientific achievements.
(R)-MDMA is more potent and efficacious as a serotonin 5-HT2A and 5-HT2B receptor agonist than (S)-MDMA, whereas (S)-MDMA is somewhat more potent as an agonist of the serotonin 5-HT2C receptor. Due to it being a more potent serotonin 5-HT2A receptor agonist than (S)-MDMA, (R)-MDMA has been hypothesized to have greater psychedelic effects than (S)-MDMA or racemic MDMA. However, this proved not to be the case in a direct clinical comparison of (R)-MDMA, (S)-MDMA, and racemic MDMA, with equivalent hallucinogen-like effects instead found between the three interventions. MDMA produces MDA as a minor active metabolite. Peak levels of MDA are about 5 to 10% of those of MDMA and total exposure to MDA is almost 10% of that of MDMA with oral MDMA administration. As a result, MDA may contribute to some extent to the effects of MDMA. MDA is an entactogen, stimulant, and weak psychedelic similarly to MDMA. Like MDMA, it acts as a potent and well-balanced SNDRA and as a weak serotonin 5-HT2 receptor agonist. However, MDA shows much more potent and efficacious serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptor agonism than MDMA. Accordingly, MDA produces greater psychedelic effects than MDMA in humans and might particularly contribute to the mild psychedelic-like effects of MDMA. On the other hand, MDA may also be importantly involved in toxicity of MDMA, such as cardiac valvulopathy. The duration of action of MDMA (3–6 hours) is much shorter than its elimination half-life (8–9 hours) would imply.
Sources: en.wikipedia.org
==== Reduced probability of contamination ==== DMF-based workflows, particularly those using a closed configuration with a top-plate ground electrode, have been shown to be less susceptible to outside contamination compared to some conventional laboratory workflows. This can be attributed to minimal user interaction during automated steps, and the fact that the smaller volumes are less exposed to environmental contaminants than larger volumes which would need to be exposed to open air during mixing. Ruan et al. observed minimal contamination from exogenous nonhuman DNA and no cross-contamination between samples while using their DMF-based digital whole genome sequencing system.
==== Cash-and-carry wholesale ==== A "cash-and-carry" operator sells from a warehouse-style site where business customers generally pay at purchase and transport goods themselves. This model is common for small retailers and food service buyers in many countries.
DiCaprio has mentioned growing up poor in a neighborhood plagued with prostitution, crime and violence. He was raised Catholic. DiCaprio attended the Los Angeles Center for Enriched Studies for four years and later Seeds Elementary School. He enrolled at John Marshall High School, but disliked public school and wanted to audition for acting jobs instead. He decided to drop out of high school, and later earned a general equivalency diploma (GED). As a child, DiCaprio wanted to become either an actor or a marine biologist. He chose to pursue acting because he enjoyed imitating people and impersonating characters, and liked seeing people's reactions to his impressions. According to DiCaprio, his interest in performing began at the age of two, when he went onstage at a performance festival and danced spontaneously to a positive response from the crowd. He was also motivated to learn acting when his stepbrother's appearance in a television commercial earned him $50,000. DiCaprio has said in interviews that his first television appearance was in the children's series Romper Room, and that he was dismissed from the show for being disruptive. The show's host has denied that any children were removed from the show in this way. At age 11, DiCaprio almost quit acting to pursue breakdancing, after winning second place in a breakdancing competition in his mother's native Germany. Starting at age 14, he appeared in several commercials for Matchbox cars, which he calls his first role. DiCaprio also appeared in commercials for Kraft Singles, Bubble Yum, and Apple Jacks.
Their large size and fearsome reputation make them popular zoo exhibits. In the wild, their range has been reduced by human encroachment and is likely to contract further from the effects of climate change; hence, they are listed as Endangered by the IUCN Red List. They are protected under Indonesian law, and the Komodo National Park was founded in 1980 to aid protection efforts. In the Komodo language, the dragons are called sebae 'twins' out of a traditional belief by the Komodo people that they share the same spiritual mother as the dragons. Meanwhile, the Baar people, who speak the Baar dialect of Riung language, call the Komodo dragon mbau.
=== Pain treatment based on cell micro-encapsulation === In 1998, the Altran Foundation prize was awarded to the Toulouse-Rangueil University laboratory, and to the Kappa Biotech company for their pain-treatment project based on cell micro-encapsulation. The micro-encapsulation process stops the organism from rejecting these cells by protecting them in a sphere, thus preventing the immune system from recognizing them. The process involves creating biocompatible micro-membranes which are implanted using in-vitro fertilization which is live allogeneic or xenogenic cells that are wrapped in a semi-permeable immune-sparing membrane using a bioengineering technique known as cell encapsulation for therapeutic purposes. Until recently, the implantation posed a number of productivity problems, as it was taking 15 minutes for one micro-membrane to be implanted. Altran teams stepped in to help solve this problem. Their studies demonstrated that the automated implantation option, using a laser optical guidance system, was the most promising approach. With the cooperation of Tarbes E.N.I. students, Altran consultants developed a robot to automate the microcapsule filling operation using a dual-needle system. The robot is now commercialized.
Sources: en.wikipedia.org
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.