This is a working overview of 胸腺素α1, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2025-12-31. Anything still debated is marked as such rather than presented as settled.
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。
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.
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.
| Property | Value | Notes |
|---|---|---|
| 化学分类 | 线性肽 | 由28个氨基酸组成 |
| 分子量 | 约3108 Da | 合成版本一致 |
| 外观 | 白色至类白色粉末 | 冻干品 |
| 溶解度 | 易溶于水 | 微溶于有机溶剂 |
| 储存温度 | -20°C（冻干） | 溶解后2-8°C |
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 short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
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.
The peptide is generated in cells by cleavage of prothymosin alpha, a larger acidic protein encoded by the PTMA gene. Prothymosin alpha is expressed in many tissues, not only in the thymus, and its functions include nuclear roles in chromatin-related processes. The 28-residue fragment corresponds to the N-terminal portion of that precursor. How the cleavage occurs and how the fragment's concentration is regulated remain open questions; circulating amounts are small and difficult to measure reliably with routine assays.
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.
Immunological studies connect the peptide to multiple parts of the immune response. It has been reported to engage Toll-like receptor signaling, to promote dendritic cell maturation, and to influence the balance of T helper cell subsets. Changes in natural killer cell activity and in cytokine release appear in cell culture and animal models. These observations describe broad immunomodulatory behavior rather than a single defined receptor target, and the primary molecular interaction has not been settled.
Thymosin alpha-1 is a synthetic 28-amino-acid peptide whose sequence was first identified in extracts of bovine thymus tissue during the 1970s. The chain carries an acetyl group on its N-terminal serine. Its acidic residue content is high, which produces strong water solubility and an isoelectric point well below neutrality. Material supplied for laboratory and clinical use is manufactured by solid-phase peptide synthesis rather than purified from animal tissue. Different salt forms, such as the acetate, alter the counter-ion content without changing the peptide backbone.
Whether the free 28-residue peptide circulates in human tissue remains debated. The best-documented human source is prothymosin alpha, a larger acidic protein that carries the sequence at its N-terminus. Reports of measurable peptide levels in serum and lymphoid tissue exist, yet some of that signal may come from cross-reacting fragments or from the parent protein. Most reviews therefore treat prothymosin alpha as the established human molecule and describe independent circulation of the small peptide as an unresolved question.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
The central area, or hepatic hilum, includes the opening known as the porta hepatis which carries the common bile duct and common hepatic artery, and the opening for the portal vein. The duct, vein, and artery divide into left and right branches, and the areas of the liver supplied by these branches constitute the functional left and right lobes. The functional lobes are separated by the imaginary plane, Cantlie's line, joining the gallbladder fossa to the inferior vena cava. The plane separates the liver into the true right and left lobes. The middle hepatic vein also demarcates the true right and left lobes. The right lobe is further divided into an anterior and posterior segment by the right hepatic vein. The left lobe is divided into the medial and lateral segments by the left hepatic vein. The hilum of the liver is described in terms of three plates that contain the bile ducts and blood vessels. The contents of the whole plate system are surrounded by a sheath. The three plates are the hilar plate, the cystic plate and the umbilical plate and the plate system is the site of the many anatomical variations to be found in the liver.
hydron (H+) Informally synonymous with proton. The cationic form of atomic hydrogen; i.e. a positively charged hydrogen nucleus of any isotopic composition. Thus the term can refer to a proton (11H+), deuteron (21H+), or triton (31H+).
== Evolutionary history == The MHC class I genes originated in the most recent common ancestor of all jawed vertebrates, and have been found in all living jawed vertebrates that have been studied thus far. Since their emergence in jawed vertebrates, this gene family has been subjected to many divergent evolutionary paths as speciation events have taken place. There are, however, documented cases of trans-species polymorphisms in MHC class I genes, where a particular allele in an evolutionary related MHC class I gene remains in two species, likely due to strong pathogen-mediated balancing selection by pathogens that can infect both species. Birth-and-death evolution is one of the mechanistic explanations for the size of the MHC class I gene family.
=== Capsicum peppers === Capsicum chili peppers are commonly used to add pungency in cuisines worldwide. The range of pepper heat reflected by a Scoville score is from 500 or less (sweet peppers) to over 2.6 million (Pepper X) (table below; Scoville scales for individual chili peppers are in the respective linked article). Some peppers such as the Guntur chilli and Rocoto are excluded from the list due to their very wide SHU range. Others such as Dragon's Breath and Chocolate 7-pot have not been officially verified.
Sources: en.wikipedia.org
== Cultivation == Many Japanese plant ashitaba in herb gardens, flower pots, and backyards. This is due to the modest conditions for cultivation and fast rate of growth. This is a cold hardy plant, with optimal temperatures ranging between 12 and 22 °C. Harvesting a leaf at the break of day often results in a new sprout growing overnight, being visible the following morning, hence the name "tomorrow's leaf".
Austin held on to the WWF Championship until SummerSlam on August 22 when he lost it to Mankind in a triple threat match also featuring Triple H. in the two months that followed, Triple H would gain possession of the title. Austin would get his rematch at No Mercy on October 17 against Triple H, but Austin lost after The Rock accidentally struck him with a sledgehammer shot meant for Triple H. The three were advertised for a triple-threat match at Survivor Series on November 14, where Austin was run down by a car. The segment was to write him off television, with the neck injury suffered two years prior posing a real threat of early retirement, and was advised to undergo surgery. Austin would later describe this as "the worst storyline I was ever involved in". Austin made a one-off appearance at Backlash on April 30, 2000, attacking Triple H and Vince McMahon to help The Rock reclaim the WWF Championship. After Austin's official return at Unforgiven on September 24, Commissioner Mick Foley led an investigation to find out who ran Austin over, with the culprit revealed to be Rikishi. At No Mercy on October 22, Austin faced Rikishi in a No Holds Barred match, during which Austin attempted to run Rikishi down in a truck, but was prevented from doing so by officials, and the match was deemed a no contest; Austin was subsequently arrested. During a handicap match against Rikishi and Kurt Angle, Triple H came down with the apparent intention of teaming with Austin, only to hit Austin with a sledgehammer and reveal he had instructed Rikishi to run him over.
A sperm bank, semen bank, or cryobank is a facility that purchases, stores, and sells human semen. The semen is produced and sold by men who are known as sperm donors. The sperm is purchased by other persons for the purpose of achieving a pregnancy other than by a sexual partner. Sperm sold by a sperm donor is known as donor sperm. A sperm bank may be a separate entity supplying donor sperm to individuals or to fertility clinics, or it may be a facility which is run by a clinic for their customers. A pregnancy may be achieved using donor sperm for insemination with similar outcomes to sexual intercourse. By using sperm from a donor rather than from the sperm recipient's partner, the process is a form of third party reproduction. In the 21st century artificial insemination with donor sperm from a sperm bank is most commonly used for individuals with no male partner, such as single women and coupled lesbians. A sperm donor must generally meet specific requirements regarding age and screening for adverse medical history. In the United States, sperm banks are regulated as Human Cell and Tissue or Cell and Tissue Bank Product (HCT/Ps) establishments by the Food and Drug Administration. Many states in the U.S. also have regulations in addition to those imposed by the FDA. In the European Union a sperm bank must have a license, according to the EU Tissue Directive. In the United Kingdom, sperm banks are regulated by the Human Fertilisation and Embryology Authority.
From the evident difference in the transport of solution and channel appearance, one can identify the separation effect for the determination of blood type. Noiphung et al. at 2014 followed up an approach in paper-based microfluidic blood typing using antibodies to cause red blood cells agglutination, and the group designed a new paper-based analytical device (PAD) for blood grouping that can be used for the synchronous performation of Rh and forward and reverse ABO blood grouping on the same device. Forward grouping is a blood typing procedure whereby patient red blood cells are mixed with Anti-A and Anti-B reagents. On the other hand, reverse typing is a blood typing procedure where patient serum is mixed with reagent A cells and reagent B cells. The results should be the opposite of forward typing. The designed device has two sides: forward (F) side, made of chromatography paper with three channels spotted with 1.5 mL Anti-A, Anti-B, and Anti-D antibody solutions each, and reverse (R) side, made with blood separation membrane and connected to A-type and B-type antibodies channels. The PAD is fabricated using a combination of wax dipping technologies to join Whatman chromatography paper and blood separation membrane. The device included three wax-printed channels for forward grouping, two of which were also applied for reverse grouping. While R-side was capable for whole blood sample analysis, Noiphung's group found that whole blood samples are too viscous to be directly applied on a paper-side of the device.
=== Awards and honours === Williams was appointed Member of the Order of the British Empire (MBE) in the 2010 New Year Honours for services to the community in North Oxford. He was elected a Fellow of the Royal Society (FRS) in 1972 and was a Foreign Member of the Swedish, Portuguese, Czechoslovak and Belgian science academies. He was a medallist of the Biochemical Society (twice), the Royal Society (twice), the Royal Society of Chemistry (three times), the Federation of European Biochemical Societies (twice) and the International Union of Biochemistry. He delivered the Bakerian Lecture in 1981 and won the Royal Medal in 1995.
Sources: en.wikipedia.org
== History == The method of thermospray ionization was first introduced by a patent evidenced as early as 1983, and described in further detail by a patent published on March 8, 1988. Inventors Marvin L. Vestal and Calvin R. Blakley proposed an ion vapor source for mass spectrometry of liquids under a US Grant from the Department of Health, Education, and Welfare. The proposed method detailed a coupling device between liquid chromatographic columns and various methods of detection for gaseous samples; like mass spectrometry, electron capture, atomic adsorption, etc. Four different representations of the thermospray vaporizer were presented in the 1988 patent – UA4730111A. Nonvolatile, ionic, and thermally labile solutes were investigated with the various control systems on the vaporizers to achieve partial vaporization.
Therefore, she maintained that the cyclol model of globular proteins was still potentially viable and even proposed the cyclol fabric as a component of the cytoskeleton. However, most protein scientists ceased to believe in it and Wrinch turned her scientific attention to mathematical problems in X-ray crystallography, to which she contributed significantly. One exception was physicist Gladys Anslow, Wrinch's colleague at Smith College, who studied the ultraviolet absorption spectra of proteins and peptides in the 1940s and allowed for the possibility of cyclols in interpreting her results. As the sequence of insulin began to be determined by Frederick Sanger, Anslow published a three-dimensional cyclol model with sidechains, based on the backbone of Wrinch's 1948 "minimal cyclol" model.
Link-N (DHLSDNYTLDHDRAIH) is a naturally occurring 16-amino acid peptide which is the N-terminal fragment derived from enzymatic cleavage of cartilage link protein. It has antiinflammatory effects and stimulates cartilage regrowth in both in vitro cultures of human cartilage tissue and animal models of arthritis, but is not known to have been tested in humans.
=== Biologically-derived units === The extremely strong complexation between avidin and biotin is instrumental in blood clotting, and has been used as the recognition motif to construct synthetic systems. The binding of enzymes with their cofactors has been used as a route to produce modified enzymes, electrically contacted enzymes, and even photoswitchable enzymes. DNA has been used both as a structural and as a functional unit in synthetic supramolecular systems.
The area of a familiar country, state or city is often used as a size reference, especially in journalism. Usually the region is used to describe something of similar size to the reference region, but in some cases such references become common enough that multiples of the area start to be used, as in "twice the area of Wales". Besides Wales (20,779 km2 (8,023 sq mi)), other regions that have been used this way include Belgium (30,528 km2 or 11,787 mi2), the German state of Saarland (2,569.69 km2 or 992.16 mi2), and Washington, D.C. (61.4 mi2 or 159 km2).
Sources: en.wikipedia.org
它不是经典的内分泌激素，而是一种免疫调节肽。其作用主要通过局部免疫细胞间的信号传递实现，而非经血液循环作用于远隔器官。
天然胸腺素α1主要从胸腺组织提取，也可在脾脏和淋巴结中检出。目前研究和临床使用的多为化学合成版本，不再依赖动物组织。
胸腺素组分5是牛胸腺提取物的粗组分，包含多种肽。胸腺素α1是其中一种被纯化和表征的单一肽，具有明确的28个氨基酸序列。
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.