A practical reference on Thymosin alpha 1: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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。
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.
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.
| 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 |
Thymosin alpha 1 is a synthetic 28-amino-acid peptide first isolated in 1966 from thymosin fraction 5, a bovine thymus extract. Its chain begins with an acetylated serine residue and ends with asparagine. The native peptide carries a molecular mass near 3,108 daltons. Researchers classify it as an immunomodulatory agent rather than a hormone with a single endocrine target. Early work framed it as a thymus-derived factor that supports T-cell maturation. The synthetic form used in research and clinical products matches the natural sequence.
Immune signaling studies link thymosin alpha 1 to Toll-like receptor pathways, particularly TLR2 and TLR9, on dendritic cells and other antigen-presenting cells. Activation of these receptors promotes maturation of T cells and increases natural killer cell activity. The peptide shifts cytokine output toward a T helper 1 profile, raising interferon gamma and interleukin 2 while modulating interleukin 10. Whether these effects translate into clinical benefit for any specific disease remains a subject of debate. Reported outcomes vary across trials and populations.
Thymosin alpha 1 is approved as a medicine in several countries, including Italy and China, for indications such as chronic hepatitis B and as an immune adjuvant. It is not approved by the United States Food and Drug Administration as a therapeutic product. In research settings the peptide appears in studies of sepsis, vaccine response, and oncology support, often with mixed or inconclusive results. The evidence base is uneven, and reviews note that many trials were small. Regulatory status therefore differs widely between jurisdictions.
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
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.
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.
antiseptics, which are applied to living tissue/skin disinfectants, which destroy microorganisms found on non-living objects. antibiotics, called prophylactic when given as prevention rather as treatment of infection. However, long term use of antibiotics leads to resistance of bacteria. While humans do not become immune to antibiotics, bacteria do. Thus, avoiding using antibiotics longer than necessary helps prevent bacteria from forming mutations that aid antibiotic resistance. One of the ways to prevent or slow down the transmission of infectious diseases is to recognize the different characteristics of various diseases. Some critical disease characteristics that should be evaluated include virulence, distance traveled by those affected, and level of contagiousness. The human strains of Ebola virus, for example, incapacitate those infected extremely quickly and kill them soon after. As a result, those affected by this disease do not have the opportunity to travel very far from the initial infection zone. Also, this virus must spread through skin lesions or permeable membranes such as the eye. Thus, the initial stage of Ebola is not very contagious since its victims experience only internal hemorrhaging. As a result of the above features, the spread of Ebola is very rapid and usually stays within a relatively confined geographical area. In contrast, the human immunodeficiency virus (HIV) kills its victims very slowly by attacking their immune system.
=== Photosynthetic carbohydrate synthesis === Photosynthetic carbohydrate synthesis in plants and certain bacteria is an anabolic process that produces glucose, cellulose, starch, lipids, and proteins from CO2. It uses the energy produced from the light-driven reactions of photosynthesis, and creates the precursors to these large molecules via carbon assimilation in the photosynthetic carbon reduction cycle, a.k.a. the Calvin cycle.
== Doubts about existence == In October 2011 the Journal of Strategic Studies, a leading journal in that field, published an article by Thomas Rid, "Cyber War Will Not Take Place" which argued that all politically motivated cyber attacks are merely sophisticated versions of sabotage, espionage, or subversion – and that it is unlikely that cyber war will occur in the future.
Sources: en.wikipedia.org
==== AICAR transformylase ==== AICAR transformylase requires the coenzyme N10-formyltetrahydrofolate (N10-formyl-THF) as the formyl donor for the formylation of AICAR to FAICAR. However, AICAR transformylase and GAR transformylase do not share a high sequence similarity or structural homology.
During Bush's second term, a controversy arose over the Justice Department's midterm dismissal of seven United States Attorneys. The White House maintained that they were fired for poor performance. Attorney General Alberto Gonzales later resigned over the issue, along with other senior members of the Justice Department. The House Judiciary Committee issued subpoenas for advisers Harriet Miers and Josh Bolten to testify regarding this matter, but Bush directed Miers and Bolten not to comply with those subpoenas, invoking his right of executive privilege. Bush maintained that all his advisers were covered under a broad executive privilege protection to receive candid advice. The Justice Department determined that the President's order was legal. Although congressional investigations focused on whether the Justice Department and the White House were using the U.S. Attorney positions for political advantage, no official findings have been released. On March 10, 2008, the Congress filed a federal lawsuit to enforce their issued subpoenas. On July 31, 2008, a United States district court judge ruled that Bush's top advisers were not immune from congressional subpoenas. In all, twelve Justice Department officials resigned rather than testify under oath before Congress. They included Attorney General Alberto Gonzales and his chief of staff Kyle Sampson, Gonzales' liaison to the White House Monica Goodling, aide to the president Karl Rove and his senior aide Sara Taylor.
=== "Central Dogma" === Watson and Crick's model attracted great interest immediately upon its presentation. Arriving at their conclusion on February 21, 1953, Watson and Crick made their first announcement on February 28. In an influential presentation in 1957, Crick laid out the "central dogma of molecular biology", which foretold the relationship between DNA, RNA, and proteins, and articulated the "sequence hypothesis." A critical confirmation of the replication mechanism that was implied by the double-helical structure followed in 1958 in the form of the Meselson–Stahl experiment. Messenger RNA (mRNA) was identified as an intermediate between DNA sequences and protein synthesis by Brenner, Meselson, and Jacob in 1961. Then, work by Crick and coworkers showed that the genetic code was based on non-overlapping triplets of bases, called codons, and Har Gobind Khorana and others deciphered the genetic code not long afterward (1966). These findings represent the birth of molecular biology.
Sources: en.wikipedia.org
As with cocaine in Coca-Cola, lithium was widely marketed as one of several patent medicine products popular in the late 19th and early 20th centuries and was claimed to be included in many drinks including lithia water and 7 Up. Charles Leiper Grigg, who launched his St. Louis-based company The Howdy Corporation, invented a formula for a lemon-lime soft drink in 1920. The product, at one point named "7Up Lithiated Lemon Soda", was launched two weeks before the Wall Street Crash of 1929. It claimed to contain the mood stabilizer lithium citrate, and was one of many patent medicine products popular in the late-19th and early-20th centuries. All references to lithium were removed in 1937 after it became clear that 7Up contains no lithium. Many sources written by scientists (instead of historians) incorrectly report that 7 Up was forced to remove lithium in 1948, with an FDA action that supposedly banned lithium from beverages. Despite the supposed ban, in 1950, the Painesville Telegraph still carried an advertisement for a lithiated lemon beverage.
Regenerative medicine has been studied by dentists to find ways that damaged teeth can be repaired and restored to obtain natural structure and function. Dental tissues are often damaged due to tooth decay, and are often deemed to be irreplaceable except by synthetic or metal dental fillings or crowns, which requires further damage to be done to the teeth by drilling into them to prevent the loss of an entire tooth. Researchers from King's College London have created a drug called Tideglusib that claims to have the ability to regrow dentin, the second layer of the tooth beneath the enamel which encases and protects the pulp (often referred to as the nerve). Animal studies conducted on mice in Japan in 2007 show great possibilities in regenerating an entire tooth. Some mice had a tooth extracted and the cells from bioengineered tooth germs were implanted into them and allowed to grow. The result were perfectly functioning and healthy teeth, complete with all three layers, as well as roots. These teeth also had the necessary ligaments to stay rooted in its socket and allow for natural shifting. They contrast with traditional dental implants, which are restricted to one spot as they are drilled into the jawbone. A person's baby teeth are known to contain stem cells that can be used for regeneration of the dental pulp after a root canal treatment or injury. These cells can also be used to repair damage from periodontitis, an advanced form of gum disease that causes bone loss and severe gum recession.
== Industrial relevance == Aminoacylases have been used for the production of L-amino acids in industrial settings since the late 1950s. Since aminoacylases are substrate specific for N-acyl-L-amino acids and not N-acyl-D-amino acids, aminoacylases can be used to reliably take a mixture of these two reactants and only convert the L enantiomers into products - which can then be isolated by solubility from the unreacted N-acyl-D-amino acids. While this process was done in a batch reactor for many years, a faster and less wasteful process was developed in the late 1970s that placed aminoacylases in a column that N-acyl-amino acids were then continuously washed through. This process is still used in industrial settings today to convert N-acyl-amino acids to amino acids in an enantiomerically specific way.
Studies indicate that a substantial part of the modern vehicle's value comes from intelligent systems, and that these represent most of the current automotive innovation. To facilitate this, the modern automotive engineering process has to handle an increased use of mechatronics. Configuration and performance optimization, system integration, control, component, subsystem and system-level validation of the intelligent systems must become an intrinsic part of the standard vehicle engineering process, just as this is the case for the structural, vibro-acoustic and kinematic design. This requires a vehicle development process that is typically highly simulation-driven.
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。
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.