胸腺素α1 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-03-27. Numbers and descriptions here follow the published literature rather than marketing material.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids, corresponding to the N-terminal fragment of prothymosin alpha. Its sequence begins with acetylation at the N-terminus, a modification that affects stability and receptor interaction. The peptide is acidic, with a calculated isoelectric point near 4.2, and carries no disulfide bonds, so its secondary structure is largely flexible in solution. Molecular mass is approximately 3108 daltons. The native form was first isolated from bovine thymus tissue, while pharmaceutical material is produced by solid-phase peptide synthesis.
Within the immune system, the peptide acts on several cell types rather than a single target. Reported activities include promotion of T-cell maturation, enhancement of natural killer cell activity, and modulation of cytokine production by dendritic cells and macrophages. Some of these effects appear to operate through toll-like receptor signaling, though the precise receptor-level mechanism remains debated. Whether the observed immune changes translate into clinical benefit is a separate question and depends on the indication studied.
Thymosin alpha-1 is a short peptide of 28 amino acid residues first described in the 1970s as a component of thymic extracts. Its N-terminal residue carries an acetyl group, and the sequence is highly conserved across mammalian species. The peptide is not encoded as a standalone gene product; it is released by proteolytic cleavage from the N-terminus of prothymosin alpha, a larger acidic nuclear protein. That precursor relationship places it within a broader family of thymic and immune-associated peptides that have been studied for decades.
The activity of this peptide is generally described as immunomodulatory rather than directly antimicrobial. Experimental work links it to signaling through certain Toll-like receptors on dendritic cells and to downstream maturation of antigen-presenting cells. Reported effects include expansion of T cell subsets, shifts in cytokine profiles, and increased natural killer cell activity. These observations come largely from cell culture and animal models, and the precise receptor-level events in humans remain incompletely characterized.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic peptide, 28 residues | N-terminal fragment of prothymosin alpha |
| Molecular mass | About 3108 Da | Acetylated form |
| Isoelectric point | Near 4.2 | Acidic peptide |
| Appearance | White to off-white lyophilized powder | Common supplied form |
| Typical storage | -20 °C or below, dry | Solution stability is lower |
市售的胸腺素α1通常以冻干粉形式提供，溶解后用于注射。其氨基酸组成包括多个酸性残基，因此在中性pH下带负电荷。该肽可溶于水和生理盐水，但在有机溶剂中溶解度有限。储存条件通常为冻干状态下负20摄氏度，溶解后需冷藏并避免反复冻融。常见的同义词包括胸腺肽α1、thymalfasin和Tα1。
胸腺素α1（thymosin alpha 1，Tα1）是一种由28个氨基酸组成的酸性肽，N端被乙酰化，分子量约为3108道尔顿。该肽最早从牛胸腺组织提取物中分离，属于胸腺素组分5的一个成分。其序列在不同哺乳动物中高度保守，提示其具有基本的生物学功能。名称中的“α1”指其在电泳中的迁移位置，并非表示亚型编号。它既存在于胸腺，也存在于脾脏和淋巴结等免疫组织。
20世纪70年代，研究者从胸腺提取物中纯化出多种小肽，Tα1是其中被较早表征的一种。最初的制备依赖组织匀浆和层析步骤，产量低且成分复杂。随着固相肽合成技术成熟，实验室和工业界能够生产与天然序列一致的合成版本。合成肽的纯度可达95%以上，并可通过反相高效液相色谱和质谱进行鉴定。这一转变使研究不再依赖动物胸腺来源。
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
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.
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.
== Clinical trials == Innovation Pharmaceuticals advanced brilacidin through early stage human clinical trials to a completed Phase 2a proof-of-concept clinical trial. Since acquisition, brilacidin was entered into a Phase 2b clinical trial. Brilacidin was granted the Qualified Infectious Disease Product (QIDP) designation by the FDA under the Generating Antibiotic Incentives Now Act of 2011 (GAIN Act).
Kropotkin, Peter Alexeivitch (1911). "Cossacks" . Encyclopædia Britannica. Vol. 7 (11th ed.). p. 218. "Cossacks during the Napoleonic Wars". "Zaporizhian Cossacks". "Encyclopedia of Ukraine". "History of Ukrainian Cossacks". "Encyclopedia of Ukraine". Soviet Cossacks (photography). Archived from the original on 2011-11-13. Retrieved 2010-07-27. – an issue of the propaganda journal USSR in Construction which presents numerous images of Cossack life in Soviet Russia. "Cossack Nation Live journal". {{cite web}}: Check |url= value (help) "Cossack Nation – The Social Network of Ethnic Cossacks". "The Congress of Cossacks in America". "Pirate, Rebel, Freedom Fighter, Champion of the Poor". Archived from the original on 2007-08-05. Retrieved 2015-04-03. "History of the Cossacks 15–21st centuries". Open Public Library. Documents, maps, illustrations Peeling, Siobhan. "Cossacks". "International Encyclopedia of the First World War". 1914–1918 online. Archived from the original on 2019-12-30. Retrieved 2019-06-18.
== External links == "BRENDA". Archived from the original on 1 April 2022., Database of enzymes giving lists of known inhibitors for each entry "PubChem". National Center for Biotechnology Information. National Library of Medicine. Database of drugs and enzyme inhibitors "Symbolism and Terminology in Enzyme Kinetics". Archived from the original on 20 June 2006. Recommendations of the Nomenclature Committee of the International Union of Biochemistry (NC-IUB) on enzyme inhibition terminology
== Pulmonary effects == In smoking, long-term exposure to compounds found in the smoke (e.g., carbon monoxide and cyanide) are believed to be responsible for pulmonary damage and for loss of elasticity in the alveoli, leading to emphysema and chronic obstructive pulmonary disease (COPD). COPD caused by smoking is a permanent, incurable, and often terminal reduction of pulmonary capacity characterized by shortness of breath, wheezing, persistent cough with sputum, and damage to the lungs, including emphysema and chronic bronchitis. The carcinogen acrolein and its derivatives also contribute to the chronic inflammation present in COPD.
Sources: en.wikipedia.org
=== Production === It is traditionally obtained by hydrolysis of various sources of protein, such as gelatin. It is obtained commercially by fermentation. In this way, 25-35 g/liter can be produced, using glucose as a carbon source.
== History == The concept of fatty acid (acide gras) was introduced in 1813 by Michel Eugène Chevreul, though he initially used some variant terms: graisse acide and acide huileux ("acid fat" and "oily acid").
Beginning with the colonial era and intensifying after the South American states had gained their independence, large landowners appropriated all or most of the land and forced the Native population into bondage (known in Ecuador as Huasipungo, from Kichwa wasipunku, "front door"). Harsh conditions of exploitation repeatedly led to revolts by the Indigenous farmers, which were forcibly suppressed. The largest of these revolts occurred in 1780–1781 under the leadership of Husiy Qawriyil Kunturkanki (Túpac Amaru II).Some Indigenous farmers re-occupied their ancestors' lands and expelled the landlords during the takeover of governments by dictatorships in the middle of the 20th century, such as in 1952 in Bolivia (Víctor Paz Estenssoro) and 1968 in Peru (Juan Velasco Alvarado). The agrarian reforms included the expropriation of large landowners. In Bolivia, there was a redistribution of the land to the Indigenous population as their private property. This disrupted traditional Quechua and Aymara culture based on communal ownership, but ayllus has been retained up to the present time in remote regions, such as in the Peruvian Quechua community of Q'ero. The struggle for land rights continues up to the present time to be a political focal point of everyday Quechua life. The Kichwa ethnic groups of Ecuador which are part of the ECUARUNARI association were recently able to regain communal land titles or the return of estates—in some cases through militant activity.
=== IRAP allosteric site inhibitors === Spiro-oxindole dihydroquinazolines During a screening process in 2016, a spiro-oxindole dihydroquinazoline compound was identified as one of the most potent hits towards IRAP. This kind of compounds shows a high specificity for IRAP against APN (Compound 8 IC50 = 5.8 μM) and according to docking studies, the inhibitor acts in a binding pocket close to the GAMEN loop without interacting with the zing atom, leading to uncompetitive inhibition, confirmed later on by kinetic studies.
=== Cancer === Because MTs play an important role in transcription factor regulation, defects in MT function or expression may lead to malignant transformation of cells and ultimately cancer. Studies have found increased expression of MTs in some cancers of the breast, colon, kidney, liver, skin (melanoma), lung, nasopharynx, ovary, prostate, mouth, salivary gland, testes, thyroid and urinary bladder; they have also found lower levels of MT expression in hepatocellular carcinoma and liver adenocarcinoma. Evidence suggests that greater MT expression may cause resistance to chemotherapy.
Sources: en.wikipedia.org
=== Monitoring === Keeping MSUD under control requires careful monitoring of blood chemistry, both at home and in a hospital setting. DNPH or specialized dipsticks may be used to test the patient's urine for ketones (a sign of metabolic decompensation), when metabolic stress is likely or suspected. Fingerstick tests are performed regularly and sent to a laboratory to determine blood levels of leucine, isoleucine, and valine. Regular metabolic consultations, including blood draws for full nutritional analysis, are recommended; especially during puberty and periods of rapid growth. MSUD management also involves a specially tailored metabolic formula, a modified diet, and lifestyle precautions such as avoiding fatigue and infections, as well as consuming regular, sufficient calories in proportion to physical stress and exertion. Without sufficient calories, catabolism of muscle protein will result in a metabolic crisis. Those with MSUD must be hospitalized for intravenous infusion of sugars and nasogastric drip-feeding of formula, in the event of metabolic decompensation, or lack of appetite, diarrhea or vomiting. Food avoidance, rejection of formula, and picky eating are all common problems with MSUD. Some patients may need to receive all or part of their daily nutrition through a feeding tube. Appropriate Branched-Chain Amino Acid (BCAA) blood concentrations: LEU plasma concentrations for infants and children 5 years old and younger should be between 75-200 mmol/L.
=== Late 19th century === Following the Napoleonic Wars, the British Empire became the world's leading power, controlling one-quarter of the world's population and one-third of the land area. It enforced a Pax Britannica, encouraged trade, and battled rampant piracy. Slavery was greatly reduced around the world. Following a successful slave revolt in Haiti, Britain forced the Barbary pirates to halt their practice of kidnapping and enslaving Europeans, passed the Slavery Abolition Act 1833 which banned slavery throughout its domain, and charged its navy with ending the global slave trade. Slavery was then abolished in Russia in 1861, by the Emancipation Proclamation in the United States in 1863, and in Brazil in 1888. (see Abolitionism). Following the abolition of the slave trade, and propelled by economic exploitation, the Scramble for Africa was initiated formally at the Berlin West Africa Conference in 1884–1885. All the major European powers laid claim to the areas of Africa where they could exhibit a sphere of influence over the area. These claims did not have to have any substantial land holdings or treaties to be legitimate. The French gained major ground in West Africa, the British in East Africa, and the Portuguese and Spanish at various points throughout the continent, while Leopold II of Belgium was able to retain his personal fiefdom, Congo. Electricity, steel, and petroleum fuelled a Second Industrial Revolution which enabled Germany, Japan, and the United States to become great powers that raced to create empires of their own.
In June 2021, The Simpsons short film The Good, the Bart, and the Loki was announced, which was released alongside "Journey into Mystery", the fifth episode of Loki on Disney+. The short sees Loki teaming up with Bart Simpson in a crossover that pays homage to the characters of the MCU. Hiddleston reprises his role as Loki in the short.
==== Indirect routes of production of 99Mo ==== Other particle accelerator-based isotope production techniques have been investigated. The supply disruptions of 99Mo in the late 2000s and the ageing of the producing nuclear reactors forced the industry to look into alternative methods of production. The use of cyclotrons or electron accelerators to produce 99Mo from 100Mo via (p,pn) or (γ,n) reactions, respectively, has been further investigated. The (n,2n) reaction on 100Mo yields a higher reaction cross-section for high energy neutrons than of (n,γ) on 98Mo with thermal neutrons. In particular, this method requires accelerators that generate fast neutron spectrums, such as ones using D-T or other fusion-based reactions, or high energy spallation or knock out reactions. A disadvantage of these techniques is the necessity for enriched 100Mo targets, which are significantly more expensive than natural isotopic targets and typically require recycling of the material, which can be costly, time-consuming, and arduous.
Sources: en.wikipedia.org
It corresponds to a fragment of the larger protein prothymosin alpha, which is present in many tissues. The isolated 28-amino-acid peptide was originally obtained from thymus preparations, and the pharmaceutical product is synthesized rather than extracted. The term therefore describes both a natural fragment and a manufactured drug substance.
Thymosin alpha-1 is a single defined 28-residue peptide, while the broader family includes unrelated peptides such as thymosin beta-4. The shared name reflects historical isolation from thymus tissue rather than a common structure. Confusion between the two is common in older literature.
No single pathway fully accounts for its reported effects. Several studies describe interaction with innate immune receptors and downstream cytokine changes, but the complete picture is not settled. Open questions remain about which effects occur at physiological concentrations.
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.