If you have been reading about lyophilized powder and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-01-22. Where a claim depends on a specific study, the study is described rather than over-claimed.
The compound has been investigated as an adjunct in chronic viral hepatitis and as a vaccine adjuvant, with results that vary by study design and population. Regulators in some countries have approved a synthetic form for specific indications, while other agencies have not. Whether the peptide produces consistent clinical benefit across diverse patient groups is still an open question, and many trials have been small. Its status is therefore best described as investigational in many contexts and established only narrowly.
The name itself causes confusion, because several unrelated thymic peptides share the thymosin label. Thymosin beta-4, for example, is a different molecule with different functions. Naming conventions in the literature also mix descriptive research terms with assigned nonproprietary names, so a reader should confirm which entity a given paper addresses. Clarifying that point is usually the first step in interpreting any claim about this peptide.
The peptide occurs naturally in thymic tissue and has been detected in serum and other biological fluids. Reported concentrations are low, and reliable measurement generally requires immunoassay or mass spectrometry with an enrichment step. It is released from a larger precursor, prothymosin alpha, by proteolytic cleavage, although the enzymes involved are not fully characterized. Whether circulating levels reflect thymic output specifically remains an open question.
Thymosin alpha 1 is a 28-amino-acid peptide first isolated from thymosin fraction 5, a bovine thymic extract. Its sequence begins with an acetylated serine residue and carries a high proportion of acidic residues, so the molecule has a net negative charge near neutral pH. Despite the shared name, it is unrelated in sequence to the thymosin beta family. Synthetic material prepared by solid-phase peptide synthesis is identical in sequence to the natural peptide.
| Property | Value | Notes |
|---|---|---|
| Residue count | 28 amino acids | Acetyl group on the first residue |
| Approximate molecular mass | 3108 daltons | Calculated from the consensus sequence |
| Origin | Cleavage product of prothymosin alpha | Not encoded as a separate gene product |
| Primary research focus | Immune modulation | Studied in viral hepatitis and as a vaccine adjuvant |
| Common synonyms | Thymalfasin, Tα1, thymosin alpha 1 | Thymalfasin is the assigned nonproprietary name |
Quality control for thymosin alpha-1 focuses on identity, purity, and potency. Identity is confirmed by mass spectrometry and amino acid analysis, while purity is assessed by chromatography with limits on related substances and residual solvents. Potency assays may use cell-based immune readouts, but these are not standardized across laboratories. Regulatory status differs by jurisdiction; no product is approved in the United States for clinical use, whereas some other countries register injectable forms for specific indications.
Quantifying thymosin alpha-1 in a sample usually relies on reverse-phase high-performance liquid chromatography. The peptide lacks strong chromophores, so detection often occurs at 214 nm, where the peptide backbone absorbs. Mass spectrometry provides confirmatory identification and can detect sequence variants or truncations. Immunoassays have been used in biological matrices, but they may cross-react with related fragments. For purity assessment, chromatographic peak area gives the main component percentage, while mass accuracy verifies molecular identity.
Long-term storage is generally at minus twenty degrees Celsius or colder, preferably desiccated and protected from light. Lyophilized material is more stable than reconstituted solution, which degrades faster at room temperature. Stability depends on pH, ionic strength, and the presence of oxidising agents. Published stability data for the peptide are limited, so storage claims in catalogues should be treated as general guidance rather than measured guarantees. Freeze-thaw cycles are kept to a minimum.
Identity and purity are normally confirmed by reversed-phase high-performance liquid chromatography and mass spectrometry. The expected mass for the acetylated 28-residue peptide is close to 3108 daltons, and a mass shift indicates a modification or truncation. Peptide mapping after enzymatic digestion can resolve sequence-level questions. Counter-ion content, water content, and residual solvents are separate quality attributes that a certificate of analysis may or may not report. Aggregation is monitored by size-exclusion chromatography when relevant.
Thymosin alpha-1 is supplied as a lyophilized powder in most research settings. The solid dissolves readily in water and in common aqueous buffers, and it is typically reconstituted shortly before use. Solutions are clear and colourless at ordinary working concentrations. Because the peptide is hygroscopic, weighing and reconstitution are usually performed with minimal exposure to ambient air. Aliquots are prepared to avoid repeated freeze-thaw cycles, and working solutions are kept cold.
临床研究将Tα1用于慢性病毒感染、肿瘤辅助治疗和疫苗佐剂等场景。部分试验报告了免疫学指标改善，但临床终点获益在不同研究中并不一致。系统综述指出，研究间在人群、剂量和联合方案上差异较大，难以汇总结论。因此，Tα1的确切临床地位仍属开放问题，需要更多高质量随机对照试验来澄清。其机制研究也需从体外实验向体内模型推进。
胸腺素α1对免疫系统的影响涉及多种细胞类型。研究表明，它可促进未成熟T细胞向成熟T细胞分化，并增强T细胞对抗原刺激的增殖反应。树突状细胞在Tα1存在下表达更高水平的共刺激分子，从而更有效地呈递抗原。此外，自然杀伤细胞的活性也观察到上升。这些效应并非直接杀伤病原体，而是调节宿主免疫应答的强度与方向。
== Selectivity == In the competition of bacterial cells and host cells with the antimicrobial peptides, antimicrobial peptides will preferentially interact with the bacterial cell to the mammalian cells, which enables them to kill microorganisms without being significantly toxic to mammalian cells. With regard to cancer cells, they themselves also secrete human antimicrobial peptides including defensin, and in some cases, they are reported to be more resistant than the surrounding normal cells. Therefore, we cannot conclude that selectivity is always high against cancer cells.
== Structure == Lumican is a proteoglycan Class II member of the small leucine-rich proteoglycan (SLRP) family that includes decorin, biglycan, fibromodulin, keratocan, epiphycan, and osteoglycin. Like the other SLRPs, lumican has a molecular weight of about 40 kilodaltons and has four major intramolecular domains:
== Distribution and habitat == Species in the family Conidae are found in the tropical and subtropical seas of the world, in four biogeographic regions, including: the Indo-Pacific (with 60% of all species), the Tropical Eastern Pacific, the western Tropical Atlantic, and the eastern Tropical Atlantic, plus 10 species in the warm temperate Agulhas bioregion on the southern coast of South Africa. Fewer than one percent of fossil species have been found in more than one of the above regions. Cone snails are typically found in warm tropical seas and oceans worldwide. Cone snails reach their greatest diversity in the Western Indo-Pacific region. While the majority of cone snails are found in warm tropical waters, some species have adapted to temperate/semi-tropical environments and are endemic to areas such as the Cape coast of South Africa, the Mediterranean, or the cool subtropical waters of southern California (Californiconus californicus). They live on a variety of substrates, from the intertidal zone and deeper areas, to sand, rocks or coral reefs.
Infliximab has adverse effects, some life-threatening, common to drugs in the class of TNF-inhibiting immunosuppressants (which also includes etanercept (Enbrel) and adalimumab (Humira)). Some of the most severe are:
12 November 2013: Kamrul Hasan Abdul Quddus, a Bangladeshi who murdered his Indonesian girlfriend in 2007. He was initially found guilty of murder and sentenced to death in 2010, and had his appeal to the Court of Appeal dismissed in 2012. After changes to the law took effect in 2013, he applied for re-sentencing and was re-sentenced to life imprisonment and 10 strokes of the cane. He tried filing an appeal for a lighter sentence but was turned down by the Court of Appeal in 2014. 13 November 2013: Wang Wenfeng, a Chinese national who robbed and murdered a taxi driver in 2009, was initially convicted of murder and sentenced to death in 2011. He had also lost his appeal to the Court of Appeal in 2012. When changes to the law took effect in 2013, he applied for re-sentencing and was re-sentenced to life imprisonment and 24 strokes of the cane. The prosecution filed an appeal but withdrew it in 2015 in light of the outcome of the prosecution's appeal against Kho Jabing's life sentence. 20 May 2016: Kho Jabing, a Malaysian hanged for the 2008 robbery and murder of a construction worker. After changes to the law took effect in 2013, he applied for re-sentencing and was initially re-sentenced to life imprisonment and 24 strokes of the cane on 14 August 2013. However, after the prosecution appealed, he was sentenced to death again in a landmark ruling by a majority decision of 3–2 in the Court of Appeal and eventually hanged in the afternoon of the same day his final appeal was dismissed.
Sources: en.wikipedia.org
Manual: Healthcare providers or clinical trial coordinators manually review patient records and available trial criteria to identify potential matches. This might also include manually searching in clinical trial databases. Electronic health records (EHR). Some systems integrate with EHRs to automatically flag patients that may be eligible for trials based on their medical data. These systems may leverage machine learning, artificial intelligence or precision medicine methods to more effectively match patients to trials. These methods are faced with the challenge of overcoming the limitations of EHR records such as omissions and logging errors. Direct-to-patient services: Resources are specialized to support patients in finding clinical trials through online platforms, hotlines, and personalized support.
==== Competitive ==== A competitive inhibitor and substrate cannot bind to the enzyme at the same time. Often competitive inhibitors strongly resemble the real substrate of the enzyme. For example, the drug methotrexate is a competitive inhibitor of the enzyme dihydrofolate reductase, which catalyzes the reduction of dihydrofolate to tetrahydrofolate. The similarity between the structures of dihydrofolate and this drug are shown in the accompanying figure. This type of inhibition can be overcome with high substrate concentration. In some cases, the inhibitor can bind to a site other than the binding-site of the usual substrate and exert an allosteric effect to change the shape of the usual binding-site.
Stromelysin-1 also known as matrix metalloproteinase-3 (MMP-3) is an enzyme that in humans is encoded by the MMP3 gene. The MMP3 gene is part of a cluster of MMP genes which localize to chromosome 11q22.3. MMP-3 has an estimated molecular weight of 54 kDa.
== Current taxonomy == In the Journal of Molluscan Studies, in 2014, Puillandre, Duda, Meyer, Olivera & Bouchet presented a new classification for the old genus Conus. Using 329 species, the authors carried out molecular phylogenetic analyses. The results suggested that the authors should place all living cone snails in a single family, Conidae, containing the following genera:
Virologist Angela Rasmussen described this problem as a quality control issue that is unimportant for healthy people because adenoviruses are not significant pathogens, but added that it could produce serious adverse effects in immunocompromised individuals. Medicinal chemist Derek Lowe commented that the presence of replicating adenoviruses is unlikely to cause any major problems, but it is a "completely unnecessary risk", that it certainly will harm some people, and that providing a product different from the one described in studies undermines the credibility of all manufacturing and quality control processes, adding that some posts on the official Sputnik V Twitter account constitute "aggressive political marketing" and some make invalid claims regarding the performance of competing vaccines, such as the Pfizer-BioNTech vaccine. Anvisa said that the import ban can be reversed if Gamaleya clarifies the issues. Adenovirus infections cause only mild colds in healthy individuals, but they can cause life-threatening illnesses in immunodeficient individuals. The director of the Public Health Institute of Chile (ISP), Heriberto Garcia, said that the ISP would not necessarily reject the vaccine, even if it had replicating adenoviruses, because the risk of getting a common cold from the vaccine must be weighed against the risk of contracting COVID-19 when not vaccinated. He also said that real-world data from Argentina and Mexico showed no adverse effects greater than those seen in people vaccinated with the Pfizer-BioNTech vaccine or CoronaVac.
Sources: en.wikipedia.org
== Chemical composition == The chemical composition of soy sauce is affected by the proportions of raw materials, fermentation methodologies, fermenting molds and strains, and post-fermentation treatments. Although the formation mechanism of chemical composition in soy sauce is complex, it has been widely accepted that free amino acids, water-soluble peptides and Maillard reaction products in soy sauce are considered as essential chemical composition and to provide core sensory effects. The primary fermentation of lactic-acid-fermenting halophiles lowers the pH of the moromi, and this directly results in the acidic pH range (4.4–5.4) of soy sauce products. The secondary fermentation conducted by heterofermentative microbes provides soy sauce with a wide range of flavor and odorant compounds by breaking down macronutrients. Soy proteins and grain proteins are hydrolyzed into short peptide chains and free amino acids, which adds umami to the product. Based on the result of free amino acid analysis, the most abundant amino acids in Chinese soy sauce product are glutamic acid, aspartic acid, alanine and leucine. Starch is hydrolyzed into simple sugars which contribute to the sweet flavor in soy sauce. Legume fats may also be decomposed into short chain fatty acids, and the interactions among lipids and other macronutrients also result in a richer flavor in the final product. Non-enzymatic browning also contributes significantly to the development of the properties of soy sauce.
== Personal life == John Knox celebrated 60 years of marriage to his wife Josephine in March 2017. He died on 15 October 2018 in Edinburgh, aged 90. He is survived by his wife, four sons, 12 grandchildren, and 4 great-grandchildren.
NSAIDs (inhibit cyclooxygenase) and COX-2 selective inhibitors or coxibs Corticosteroids (inhibit phospholipase A2 production) Cyclopentenone prostaglandins may play a role in inhibiting inflammation Vitamin D3 and vitamin K2.
Prescription-only medicines (POM), which may be dispensed (sold in the case of a private prescription) by a pharmacist only to those to whom they have been prescribed Pharmacy medicines (P), which may be sold by a pharmacist without a prescription General sales list (GSL) medicines, which may be sold without a prescription in any shop The simple possession of a prescription-only medicine without a prescription is legal unless it is covered by the Misuse of Drugs Act 1971. A patient visits a medical practitioner or dentist, who may prescribe drugs and certain other medical items, such as blood glucose-testing equipment for diabetics. Also, qualified and experienced nurses, paramedics and pharmacists may be independent prescribers. Both may prescribe all POMs (including controlled drugs), but may not prescribe Schedule 1 controlled drugs, and 3 listed controlled drugs for the treatment of addiction; which is similar to doctors, who require a special licence from the Home Office to prescribe schedule 1 drugs. Schedule 1 drugs have little or no medical benefit, hence their limitations on prescribing. District nurses and health visitors have had limited prescribing rights since the mid-1990s; until then, prescriptions for dressings and simple medicines had to be signed by a doctor. Once issued, a prescription is taken by the patient to a pharmacy, which dispenses the medicine. Most prescriptions are NHS prescriptions, subject to a standard charge that is unrelated to what is dispensed.
Sources: en.wikipedia.org
It is usually classified as an immunomodulatory peptide rather than a classical hormone. It derives from the larger protein prothymosin alpha and acts mainly on immune cells. The thymosin label covers a group of distinct peptides, so the naming can be misleading.
The two share a family name but have different sequences, sizes, and functions. Thymosin beta-4 is a 43-residue peptide associated with actin binding and cell migration. Thymosin alpha-1 is a 28-residue peptide linked mainly to immune signaling.
Thymalfasin is the assigned international nonproprietary name for the synthetic 28-residue peptide. Thymosin alpha-1 is the descriptive research name for the same molecule. Which term appears depends on the context and the regulatory document.
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.