Everything below concerns 胸腺素α1. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-01-08. Where a claim depends on a specific study, the study is described rather than over-claimed.
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
Clinical interest has centered on chronic viral hepatitis, on immune restoration in various conditions, and on use as an adjuvant intended to improve responses to vaccines. Trials have reported mixed results, and regulatory status differs sharply between countries; in some places it is a prescription product, while elsewhere it is sold without an approved therapeutic indication. Because published studies vary widely in design, population, and endpoints, comparisons across them are difficult and no single conclusion covers the whole literature.
Thymosin alpha-1 is a synthetic peptide of 28 amino acid residues that corresponds to a naturally occurring fragment first isolated from thymus tissue. Its chain is acetylated at the amino terminus, a modification that shields the peptide from rapid cleavage by aminopeptidases. The molecule carries a net negative charge at physiological pH and dissolves freely in water. Researchers classify it as an immune-modulating agent rather than a classical hormone, because it acts on several cell types of both the innate and the adaptive immune system.
The peptide was identified during work in the 1970s on thymosin fraction 5, a partially purified extract of calf thymus. Investigators separated that mixture and characterized individual components, one of which they named thymosin alpha-1. The same compound later received the international nonproprietary name thymalfasin. Commercial material is produced by solid-phase peptide synthesis rather than by extraction, so synthetic and natural forms share an identical sequence. Naming conventions vary across the literature, and readers should distinguish the alpha-1 peptide from other thymosins that have unrelated sequences and functions.
Thymosin beta-4 is a separate 43-residue peptide that binds actin and participates in cell migration; it shares no sequence similarity with thymosin alpha-1 despite the common family name. Other preparative materials, such as thymosin fraction 5 and thymopoietin, contain distinct mixtures or peptides. The shared thymosin label reflects the tissue of origin used in early purification, not a common structural core. Treating these molecules as interchangeable is a frequent source of confusion in laboratory reports and in popular summaries alike.
| Property | Value | Notes |
|---|---|---|
| Molecular mass | Approximately 3,108 Da | Consistent with a 28-residue acetylated peptide |
| Residue count | 28 | Corresponds to the amino terminal region of prothymosin alpha |
| Appearance of dry powder | White to off-white solid | Slight variation between lots is normal |
| Solubility class | Freely soluble in water | Low solubility in most organic solvents |
| Common synonyms | Thymosin alpha 1, T alpha 1 | The numeral reflects an early fraction numbering scheme |
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。
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。
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.
=== Methionine synthase reductase activity === Involved in the reductive remethylation of cob(II)alamin using S-adenosylmethionine as a methyl donor. Catalyses the reaction: [methionine synthase]- cob(II)alamin + NADPH + H+ + S-adenosylmethionine → [methionine synthase]-methylcob(I)alamin + S-adenosylhomocysteine + NADP+.
== Model-based fouling control == Membrane fouling in cross-flow filtration may be managed through operating strategies derived from physical and mechanistic models. This approach is sometimes described as deterministic fouling control, and is based on the observation that fouling behavior in pressure-driven membrane systems often follows distinct regimes governed by dominant transport and deposition mechanisms. Classical descriptions, including those derived from Hermia's fouling laws, relate flux decline to pore blocking, intermediate mechanisms, and cake formation. In this context, operating parameters such as transmembrane pressure, cross-flow velocity, and flux can be selected to remain within conditions associated with limited or reversible fouling. This approach is related to established concepts such as critical flux and boundary flux, which define operating thresholds below which fouling remains controlled. Such approaches are widely applied in biopharmaceutical processes using tangential flow filtration (TFF), where control of fouling behavior is relevant for maintaining stable flux and separation performance. Recent technical analyses have proposed unified interpretations of fouling behavior based on physically derived operating regimes and system-scale transport effects. The terminology is not universally standardized and overlaps with broader model-based and mechanistic approaches to fouling control in membrane engineering.
== Applications == Since the early 20th century electron ionization has been one of the most popular ionization techniques because of the large number of applications it has. These applications can be broadly categorized by the method of sample insertion used. The gaseous and highly volatile liquid samples use a vacuum manifold, solids and less volatile liquids use a direct insertion probe, and complex mixtures use gas chromatography or liquid chromatography.
Sources: en.wikipedia.org
=== Legal status === Around the world, codeine is, contingent on its concentration, a Schedule II and III drug under the Single Convention on Narcotic Drugs. In Australia, Canada, New Zealand, Sweden, the United Kingdom, the United States and many other countries, codeine is regulated under various narcotic control laws. In some countries, it is available without a medical prescription in combination preparations from licensed pharmacists in doses up to 20 mg, or 30 mg when sold combined with 500 mg paracetamol. As of 2015, of the European Union member states, 11 countries (Bulgaria, Cyprus, Denmark, Estonia, Ireland, Latvia, Lithuania, Malta, Poland, Romania, and Slovenia) allow the sale of OTC codeine solid dosage forms.
== History == AZD-2327 was first described by 2004 and was first described in the scientific literature in 2009. The development of AZD-2327 was discontinued in 2010. It reached phase 2 clinical trials for both depressive disorders and anxiety disorders prior to its discontinuation. No reason was given for the discontinuation of its development. However, the drug was found to be ineffective for major depressive disorder in a phase 2 clinical trial. AZD-2327 was developed by AstraZeneca.
Eptifibatide (Integrilin, Millennium Pharmaceuticals, also co-promoted by Schering-Plough/Essex), is an antiplatelet drug of the glycoprotein IIb/IIIa inhibitor class. Eptifibatide is a cyclic heptapeptide derived from a disintegrin protein (P22827) found in the venom of the southeastern pygmy rattlesnake (Sistrurus miliarius barbouri). It belongs to the class of the arginine-glycine-aspartate-mimetics and reversibly binds to platelets. Eptifibatide has a short half-life. The drug is the third inhibitor of GPIIb/IIIa that has found broad acceptance after the specific antibody abciximab and the non-peptide tirofiban entered the global market.
Sources: en.wikipedia.org
On the night of 24/25 July 1261, Strategopoulos and his men approached the city walls and hid at a monastery near the Gate of the Spring. Strategopoulos sent a detachment of his men, led by some of the thelematarioi, to make their way to the city through a secret passage. This afforded them the opportunity to attack the walls from the inside, which surprised the guards and opened the gate, giving the Nicaean forces an entry into the city. The Latins were taken completely unaware, and after a short struggle, the Nicaeans gained control of the Theodosian land walls. As news of this spread across the city, the Latin inhabitants, from Emperor Baldwin II downwards, hurriedly rushed to the harbours of the Golden Horn, hoping to escape by ship. At the same time, Strategopoulos' men set fire to the Venetian buildings and warehouses along the coast to prevent them from landing there. Due to the timely arrival of the returning Venetian fleet, many of the Latins managed to evacuate to the still Latin-held parts of Greece, marking the end of the Latin occupation with the city's restoration to the Byzantines.
Parboiled rice husks (PBH) are an agricultural byproduct that would otherwise have little use. They decay over time, and allow drainage, and even retain less water than growstones. A study showed that rice husks did not affect the effects of plant growth regulators.
TAP is a heterodimeric complex, consisting of TAP1 (ABCB2) and TAP2 (ABCB3) members of the ABC transporter superfamily. The common feature of all ABC transporters is their organization: 1) into two transmembrane domains (TMDs) and 2) into two nucleotide-binding domains (NBDs). Both intramolecular domains are coupled to each other and when ATP binding is in progress, conformational changes in the TMDs allow proteasomal degradation products to move across the membrane. TAP recognizes and transports the antigen peptides produced in the cytosol straight into the ER, while tapasin recognizes the kind of peptides that have the ability to form stable complexes with MHC-I. This process is known as peptide proofreading or editing. Peptides selected through proofreading improve MHC-I stability; tapasin also contributes to the editing of immunogenic peptide epitopes. However, only lately it was proven via biochemical, biophysical, and structural studies that a key function in adaptive immunity, the catalytic mechanism of peptide proofreading, is performed by tapasin and TAPBPR (TAP-binding protein-related, a tapasin homologue).
Biotin deficiency Carotenemia Essential fatty acid deficiency Folic acid deficiency Hypervitaminosis A Hypovitaminosis A (phrynoderma) Iron deficiency Kwashiorkor Lycopenemia Maple syrup urine disease Marasmus Niacin deficiency (pellagra, vitamin B3 deficiency) Selenium deficiency Vitamin B1 deficiency (beriberi, thiamine deficiency) Vitamin B12 deficiency (cyanocobalamin deficiency) Vitamin B2 deficiency (ariboflavinosis, riboflavin deficiency) Vitamin B6 deficiency (pyridoxine deficiency) Vitamin B6 excess (pyridoxine excess) Vitamin C deficiency (scurvy) Vitamin K deficiency Zinc deficiency
Sources: en.wikipedia.org
The name reflects an early convention for naming thymus-derived fractions. The peptide is characterized and measured as a defined molecule, and it does not operate through a single classical endocrine axis.
It is a 28-residue synthetic peptide studied as an immune-modulating agent and approved as a drug in some countries. The sequence matches a naturally occurring fragment isolated from thymus tissue. It is not a hormone in the endocrine sense.
The name traces back to thymosin fraction 5, a crude thymus extract examined in the 1970s. Individual peptides in that mixture were labeled with Greek letters, and alpha-1 was one of them. The international nonproprietary name thymalfasin was assigned later.
No. Thymosin beta-4 contains 43 residues and binds actin, while thymosin alpha-1 contains 28 residues and acts on immune cells. The two sit in a historical naming group but share no sequence similarity, and they are not substitutes for one another.