Tuftsin analogue comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2025-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
| Property | Value | Notes |
|---|---|---|
| Solubility | Freely soluble in water | Also in aqueous buffers |
| Typical purity (HPLC) | 95 percent or higher | Lot-dependent |
| Dry powder storage | Minus 20 degrees Celsius | Sealed, dry, protected from light |
| Solution storage | 2 to 8 degrees Celsius | Short-term use |
| Identity confirmation | Mass spectrometry | ESI or MALDI-TOF |
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.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Several phase 1 clinical trials have been performed by experts in the field of adoptive immunotherapy of cancer. Hans Klingemann and Sally Arai completed a US trial at Rush University Medical Center (Chicago) in renal cell cancer and melanoma patients in 2008, and Torsten Tonn, MD and Oliver Ottmann, MD completed the European trial at the University of Frankfurt in patients with various solid and hematological malignancies in 2013. Armand Keating at Princess Margaret Hospital in Toronto conducted a trial in which NK-92 cells were given to patients who had relapsed after autologous bone marrow transplants for leukemia or lymphoma. In all clinical trials so far, NK-92 cells were administered as a simple intravenous infusion, dosed two or three times per treatment course, and given in the outpatient setting. Of the 39 patients enrolled across the three studies, 2 serious (grade 3–4) side-effects occurred during or after the infusion of NK-92 cells, the side effects disappeared afterward. The doses given to patients ranged from 1 × 108 cells/m2 to 1 × 1010 cells/m2 per infusion. Patients received between two and three infusions over a period of less than a week. About one-third of the treated patients had clinically meaningful responses with some of them fully recovering.
Affimer molecules, also known as adhiron, are small proteins that bind to target proteins with affinity in the nanomolar range. These engineered non-antibody binding proteins are designed to mimic the molecular recognition characteristics of monoclonal antibodies in different applications. These affinity reagents have been optimized to increase their stability, make them tolerant to a range of temperatures and pH, reduce their size, and to increase their expression in E.coli and mammalian cells.
Righthanded β-helices, typified by the pectate lyase enzyme shown at left or P22 phage tailspike protein, have a less regular cross-section, longer and indented on one of the sides; of the three linker loops, one is consistently just two residues long and the others are variable, often elaborated to form a binding or active site. A two-sided β-helix (right-handed) is found in some bacterial metalloproteases; its two loops are each six residues long and bind stabilizing calcium ions to maintain the integrity of the structure, using the backbone and the Asp side chain oxygens of a GGXGXD sequence motif. This fold is called a β-roll in the SCOP classification.
Tranexamic acid is frequently used following major trauma. Tranexamic acid is used to prevent and treat blood loss in a variety of situations, such as dental procedures, heavy menstrual bleeding, and surgeries with high risk of blood loss. Tranexamic acid has been found to decrease the risk of death due to any cause in people who have significant bleeding due to trauma. It is most effective if taken within the first three hours following major trauma. It also decreases the risk of death if given within the first three hours of brain injury.
Sources: en.wikipedia.org
Aside from the 22 proteinogenic amino acids, many non-proteinogenic amino acids are known. These either are not found in proteins (for example carnitine, GABA, ornithine) or are not produced directly and in isolation by standard cellular machinery. For example, hydroxyproline is synthesized from proline, and selenomethionine is produced by metabolic modification of methionine. Non-proteinogenic amino acids that are found in proteins are formed by post-translational modification. Such modifications can also determine the localization of the protein, e.g., the addition of long hydrophobic groups can cause a protein to bind to a phospholipid membrane. Examples:
Mass spectrometry has been successfully used to identify changes in the composition of the adhesome upon perturbation. Schiller et al. as well as Kuo et al. examined the effect of inhibition of myosin contractility on the integrin adhesome composition and found LIM domain proteins and beta-PIX to be tension sensitive. Gou et al. found little change in the cadherin adhesome after calcium depletion from the media, which essentially abrogates cell-cell adhesion. Reinhard Fassler and co-workers used proteomics on specifically engineered cell lines to distinguish between the adhesome of β1- and αv-class integrins.
The sequence of GVPa is extremely well conserved. GvpJ and gvpM, two proteins encoded in the cluster of genes required for gas vesicle synthesis in the archaebacteria Halobacterium salinarium and Halobacterium mediterranei (Haloferax mediterranei), have been found to be evolutionarily related to GVPa. The exact function of these two proteins is not known, although they could be important for determining the shape determination gas vesicles. The N-terminal domain of Aphanizomenon flos-aquae protein gvpA/J is also related to GVPa. GvpA of Halobacterium salinarum is a 76 amino acid long 8 kDa hydrophobic monomer. Gas vesicles are hollow cylindrical tubes, closed by a hollow, conical cap at each end. Both the conical end caps and central cylinder are made up of 4-5 nm wide ribs that run at right angles to the long axis of the structure. Gas vesicles seem to be constituted of two different protein components, GVPa and GVPc. GVPa, a small protein of about 70 amino acid residues, is the main constituent of gas vesicles and form the essential core of the structure.
White was married to his wife Edna for more than 40 years. He died unexpectedly on February 14, 1980, in Santa Barbara, California, where he had gone that day from his home in Palo Alto to deliver a lecture at the University of California. Several awards in the field of biochemistry have been named for White, including at Oakland University in Michigan, Wayne State University, George Washington University School of Medicine and the Gladstone Institutes. 1935 – Traveling Fellowship, American Physiological Society, for the XVth International Congress of Physiology (Leningrad and Moscow) 1938 – Eli Lilly Prize in Biochemistry 1960 – Distinguished Alumni Award, University of Denver 1967 – Sesquicentennial Alumni Award, University of Michigan 1969 – Borden Award, Association of American Medical Colleges 1959 – Doctor of Humane Letters, Yeshiva University 1975 – Doctor of Science, University of Denver
Prior to the development of intradialytic parenteral nutrition in the late 20th century, nutritional management of patients receiving dialysis primarily relied on dietary counselling, liberalized renal diets, and oral nutritional supplements; however, protein–energy wasting (PEW) remained common among patients undergoing maintenance hemodialysis. Efforts to supplement nutritional intake by providing nutrients during the dialysis procedure were attempted. As a result, IDPN became an established therapy to threat malnourished CKD stage 5 dialysis patients in the early 1990s. Generally, the patients received a set formulation containing standard amounts of dextrose, amino acids and lipids regardless of the patient's weight, dialysis time, and complicating co-morbid conditions.
Sources: en.wikipedia.org
Oligonucleotides are chemically synthesized using building blocks called nucleoside phosphoramidites. These can be normal or modified nucleosides which have protecting groups to prevent their amines, hydroxyl groups and phosphate groups from interacting incorrectly. One phosphoramidite is added at a time, the 5' hydroxyl group is deprotected and a new base is added and so on. The chain grows in the 3' to 5' direction, which is backwards relative to biosynthesis. At the end, all the protecting groups are removed. Nevertheless, being a chemical process, several incorrect interactions occur leading to some defective products. The longer the oligonucleotide sequence that is being synthesized, the more defects there are, thus this process is only practical for producing short sequences of nucleotides. The current practical limit is about 200 bp (base pairs) for an oligonucleotide with sufficient quality to be used directly for a biological application. HPLC can be used to isolate products with the proper sequence. Meanwhile, a large number of oligos can be synthesized in parallel on gene chips. For optimal performance in subsequent gene synthesis procedures they should be prepared individually and in larger scales.
ACS first established technical divisions in 1908 to foster the exchange of information among scientists who work in particular fields of chemistry or professional interests. Divisional activities include organizing technical sessions at ACS meetings, publishing books and resources, administering awards and lectureships, and conducting other events. The original five divisions were 1) organic chemistry, 2) industrial chemists and chemical engineers, 3) agricultural and food chemistry, 4) fertilizer chemistry, and 5) physical and inorganic chemistry. As of 2016, there are 32 technical divisions of ACS.
Aminoacyl-tRNA synthetase enzymes consume ATP in the attachment tRNA to amino acids, forming aminoacyl-tRNA complexes. Aminoacyl transferase binds AMP-amino acid to tRNA. The coupling reaction proceeds in two steps: aa + ATP ⟶ aa-AMP + PPi aa-AMP + tRNA ⟶ aa-tRNA + AMP The amino acid is coupled to the penultimate nucleotide at the 3′-end of the tRNA (the A in the sequence CCA) via an ester bond (roll over in illustration). Transporting chemicals out of a cell against a gradient is often associated with ATP hydrolysis. Transport is mediated by ATP binding cassette transporters. The human genome encodes 48 ABC transporters, that are used for exporting drugs, lipids, and other compounds.
the cAMP signal pathway and the phosphatidylinositol signal pathway. When a ligand binds to the GPCR it causes a conformational change in the GPCR, which allows it to act as a guanine nucleotide exchange factor (GEF). The GPCR can then activate an associated G protein by exchanging the GDP bound to the G protein for a GTP. The G protein's α subunit, together with the bound GTP, can then dissociate from the β and γ subunits to further affect intracellular signaling proteins or target functional proteins directly depending on the α subunit type (Gαs, Gαi/o, Gαq/11, Gα12/13). GPCRs are an important drug target, and approximately 34% of all Food and Drug Administration (FDA) approved drugs target 108 members of this family. The global sales volume for these drugs is estimated to be 180 billion US dollars as of 2018. It is estimated that GPCRs are targets for about 50% of drugs currently on the market, mainly due to their involvement in signaling pathways related to many diseases i.e. mental, metabolic including endocrinological disorders, immunological including viral infections, cardiovascular, inflammatory, senses disorders, and cancer. The long ago discovered association between GPCRs and many endogenous and exogenous substances, resulting in e.g. analgesia, is another dynamically developing field of the pharmaceutical research.
Sources: en.wikipedia.org
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.
Freeze-dried material is kept frozen, often at minus 20 degrees Celsius, and protected from light and moisture. Dissolved peptide is refrigerated for short-term use. Repeated freeze-thaw cycles are avoided.
A certificate of analysis typically lists purity by HPLC, the confirmed mass, appearance, and sometimes water or counter-ion content. It documents results for a specific batch. Details vary by supplier.
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.