thymalfasin 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 2026-08-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
Most published studies on thymosin alpha-1 report changes in immune measurements rather than clinical outcomes, and findings differ across designs and populations. Whether the peptide signals through one defined receptor or through several less specific interactions remains an open question. Its reported circulation half-life of a few hours complicates comparison of dosing schedules across trials. Mechanistic claims are frequently drawn from isolated cell cultures, and how far those results extend to whole organisms is unresolved.
| 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 |
Laboratory supplies of the peptide usually arrive as a lyophilized powder in sealed vials. The powder is hygroscopic, so a vial should be allowed to reach room temperature before it is opened to prevent condensation on the contents. Weighing and transfer are best performed in a low-humidity environment with clean tools. Once dissolved, the solution should be mixed gently rather than vortexed, because foaming and shear can reduce recovery of the peptide.
Storage recommendations center on low temperature, dryness, and protection from repeated freezing and thawing. The intact powder is commonly held at 20 degrees below zero Celsius or colder, while a working solution is divided into single-use aliquots to limit freeze-thaw cycles. Buffered saline or phosphate-buffered saline at neutral pH is frequently used as a diluent. Light sensitivity is not well documented, yet amber vials or foil wrapping are common practice for long-term storage of peptide stocks.
Identity and purity are assessed with a small set of standard peptide methods. Reversed-phase high-performance liquid chromatography separates the main peak from truncated or oxidized species, and its area percentage is the usual purity measure. Mass spectrometry confirms the observed molecular mass against the expected value, while amino acid analysis or peptide mapping checks composition and sequence. Specifications for research-grade material are often stated as 95 percent or higher, though the exact limit depends on the supplier and the intended use.
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。
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。
== Health risks == Acrolein is toxic and is a strong irritant for the skin, eyes, and nasal passages. The main metabolic pathway for acrolein is the alkylation of glutathione. The WHO suggests a "tolerable oral acrolein intake" of 7.5 μg per day per kg of body weight. Although acrolein occurs in French fries (and other fried foods), the levels are only a few μg per kg, meaning that one would have to consume more than their body weight in fries every day to surpass the limit set by the WHO. In response to occupational exposures to acrolein, the US Occupational Safety and Health Administration has set a permissible exposure limit at 0.1 ppm (0.25 mg/m3) at an eight-hour time-weighted average. Acrolein acts in an immunosuppressive manner and may promote regulatory cells, thereby preventing the generation of allergies on the one hand, but also increasing the risk of cancer. Acrolein was identified as one of the chemicals involved in the 2019 Kim Kim River toxic pollution incident.
Transient neonatal myasthenia gravis occurs in 10 to 15% of babies born to mothers afflicted with the disorder, and disappears after a few weeks. Congenital myasthenia, the rarest form, occurs when genes are present from both parents. Juvenile myasthenia gravis is most common in females. Congenital myasthenias cause muscle weakness and fatigability similar to those of MG. The signs of congenital myasthenia usually are present in the first years of childhood, although they may not be recognized until adulthood.
==== 1–99 ==== Environmental Protection (Controls on Injurious Substances) Regulations 1993 (S.I. 1993/1) Rail Crossing Extinguishment and Diversion Orders Regulations 1993 (S.I. 1993/9) Town and Country Planning (Public Path Orders) Regulations 1993 (S.I. 1993/10) Public Path Orders Regulations 1993 (S.I. 1993/11) Wildlife and Countryside (Definitive Maps and Statements) Regulations 1993 (S.I. 1993/12) Food Protection (Emergency Prohibitions) (Radioactivity in Sheep) Partial Revocation Order 1993 (S.I. 1993/13) Animals (Post-Import Control) Order 1993 (S.I. 1993/14) Genetically Modified Organisms (Contained Use) Regulations 1993 (S.I. 1993/15) Friendly Societies Act 1992 (Commencement No. 3 and Transitional Provisions) Order 1993 (S.I. 1993/16) Food Protection (Emergency Prohibitions) (Oil and Chemical Pollution of Fish) Order 1993 (S.I. 1993/17) Wireless Telegraphy Apparatus (Land Mobile-Satellite Service) (Low Bit Rate Data) (Exemption) Regulations 1993 (S.I. 1993/21) Local Government Finance (Miscellaneous Provisions) (England) Order 1993 (S.I. 1993/22) Lanarkshire (Hamilton) Enterprise Zones Designation Order 1993 (S.I. 1993/23) Lanarkshire (Motherwell) Enterprise Zones Designation Order 1993 (S.I. 1993/24) Lanarkshire (Monklands) Enterprise Zones Designation Order 1993 (S.I. 1993/25) Mayday Healthcare National Health Service Trust (Establishment) Order 1993 (S.I. 1993/27) Warrington Hospital National Health Service Trust (Establishment) Order 1993 (S.I. 1993/28) West Midlands Ambulance Service National Health Service Trust (Establishment) Order 1993 (S.I.
Quantum wires, which confine electrons or holes in two spatial dimensions and allow free propagation in the third. Quantum wells, which confine electrons or holes in one dimension and allow free propagation in two dimensions.
Sources: en.wikipedia.org
Some species of yeast are opportunistic pathogens that can cause infection in people with compromised immune systems. Cryptococcus neoformans and Cryptococcus gattii are significant pathogens of immunocompromised people. They are the species primarily responsible for cryptococcosis, a fungal infection that occurs in about one million HIV/AIDS patients, causing over 600,000 deaths annually. The cells of these yeast are surrounded by a rigid polysaccharide capsule, which helps to prevent them from being recognised and engulfed by white blood cells in the human body. Yeasts of the genus Candida, another group of opportunistic pathogens, cause oral and vaginal infections in humans, known as candidiasis. Candida is commonly found as a commensal yeast in the mucous membranes of humans and other warm-blooded animals. However, sometimes these same strains can become pathogenic. The yeast cells sprout a hyphal outgrowth, which locally penetrates the mucosal membrane, causing irritation and shedding of the tissues. A book from the 1980s listed the pathogenic yeasts of candidiasis in probable descending order of virulence for humans as: C. albicans, C. tropicalis, C. stellatoidea, C. glabrata, C. krusei, C. parapsilosis, C. guilliermondii, C. viswanathii, C. lusitaniae, and Rhodotorula mucilaginosa. Candida glabrata is the second most common Candida pathogen after C. albicans, causing infections of the urogenital tract, and of the bloodstream (candidemia). C. auris has been more recently identified.
About 500,000 tons of acrolein are produced in this way annually in North America, Europe, and Japan. Additionally, all acrylic acid is produced via the transient formation of acrolein. Propane represents a promising feedstock for the synthesis of acrolein (and acrylic acid).The main challenge is in fact the overoxidation to this acid. When glycerol (also called glycerin) is heated to 280 °C, it decomposes into acrolein
electron transport chain (ETC) The process by which electrons are transferred from electron donors to electron acceptors via a stepwise series of redox reactions carried out by dedicated enzymes and protein complexes, especially as a component of metabolic pathways which convert chemical energy from food into a form that is readily accessible by the cell. Most electron transport chains begin by oxidizing molecules derived from glycolysis such as NADH and FADH, converting them into a series of intermediate compounds via a specific sequence of independently catalyzed reactions, with the products of the previous reaction used as reactants in the next reaction until ultimately reaching a terminal electron acceptor. The particular compounds used as donors, intermediates, and acceptors vary widely between organisms and cell types; in aerobic respiration, the terminal acceptor is diatomic oxygen (O2), whereas anaerobic respiration uses other acceptors. In all variants, the free energy released by these reactions is coupled to the chemiosmotic pumping of protons (H+) across a membrane in order to generate an electrochemical gradient which is then used to drive the production of ATP, a process known as oxidative phosphorylation. In eukaryotes, electron transport chains are conducted by proteins embedded within the membranes of mitochondria and chloroplasts, while in prokaryotes the relevant proteins are embedded within the cell membrane.
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.
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.