thymus extract raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-09-13. 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。
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。
Thymosin alpha-1 is a synthetic peptide of 28 amino acids whose sequence matches the amino-terminal region of prothymosin alpha. The chain is acetylated at its first residue and contains one disulfide bridge between two cysteine residues, which folds the molecule into a compact loop. Its molecular formula, C129H215N33O55, corresponds to a monoisotopic mass of roughly 3,106 daltons. Material used in laboratories is made by solid-phase synthesis rather than isolated from animal tissue.
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 |
|---|---|---|
| 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 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
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.
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.
The peptide was described in the 1970s as a component of thymic extracts, and early research focused on restoring immune function in immunodeficiency states. A synthetic version entered clinical development in the 1980s and is approved as a drug in several countries for conditions such as chronic hepatitis B and certain immunodeficiencies. Approval status varies widely by jurisdiction, and in the United States it is not an approved therapeutic. Regulatory and clinical positions differ, so statements about efficacy should be tied to specific indications and studies.
== Statement addressing the disinvitation of Lisa Eckhart (2020) == At the opening of the Hamburg Harbourfront Literature Festival in September 2020, Kermani criticized two authors who had refused to share the stage with Lisa Eckhart. According to Kermani, this refusal led to Eckhart’s disinvitation. Eckhart had been invited on account of her debut novel Omama, “[…] the stage is a public space, and since an independent jury had selected her novel, she had the same right to enter that public space […].“The two authors clarified that they had not wanted for Eckhart to be disinvited.
=== All-terrain droplet actuation (ATDA) === All-terrain microfluidics is a method used to transport liquid droplets over non-traditional surface types. Unlike traditional microfluidics platform, which are generally restricted to planar and horizontal surfaces, ATDA enables droplet manipulation over curved, non-horizontal, and inverted surfaces. This is made possible by incorporating flexible thin sheets of copper and polyimide into the surface via a rapid prototyping method. This device works very well with many liquids, including aqueous buffers, solutions of proteins and DNA, and undiluted bovine serum. ATDA is compatible with silicone oil or pluronic additives, such as F-68, which reduce non-specific absorption and biofouling when dealing with biological fluids such as proteins, biological serums, and DNA. A drawback of a setup like this is accelerated droplet evaporation. ATDA is a form of open digital microfluidics, and as such the device needs to be encapsulated in a humidified environment in order to minimize droplet evaporation.
== PfSPZ development == In 2003 Sanaria ran trials in which falciparum sporozoites were manually dissected from salivary glands of mosquitos, irradiated and preserved before inoculation with one goal: to develop and commercialize a non-replicating, metabolically active PfSPZ vaccine. In human volunteer trials PfSPZ was applied subcutaneously (SC) or intradermally (ID) and such as it showed only modest immune response. When PfSPZ Vaccine was injected intravenously (IV) to nonhuman primates or mice it finally triggers CD8+ T-cells producing IFNγ. These T cells are believed to be the main immunologic mechanism to fight malaria in liver. Two first clinical trials of IV administration of PfSPZ were conducted in 2013. Previous ID or IC clinical trials didn't trigger adequate immune response. A 2014 phase 1 trial with the PfSPZ Vaccine found that more than half of the participants were protected from malaria infection for over a year after the trial. In 2014 Sanaria promoted an Indiegogo campaign to develop a robot that could dissect salivary glands of mosquitos, to make preparation and further development of vaccine much faster and easier. The crowdfunding campaign ended, after being backed by $45,024 of the $250,000 goal. The PfSPZ Vaccine candidate was granted fast track designation by the U.S. Food and Drug Administration in September 2016. A study published in 2017 reported complete protection after 10 weeks with three doses of PfSPZ-CVac. In April 2019, a phase 3 trial in Bioko was announced, scheduled to start in early 2020.
Sources: en.wikipedia.org
== Static gas mass spectrometry == A static gas mass spectrometer is one in which a gaseous sample for analysis is fed into the source of the instrument and then left in the source without further supply or pumping throughout the analysis. This method can be used for 'stable isotope' analysis of light gases (as above), but it is particularly used in the isotopic analysis of noble gases (rare or inert gases) for radiometric dating or isotope geochemistry. Important examples are argon–argon dating and helium isotope analysis.
A refrigerator, commonly shortened to fridge, is a commercial and home appliance consisting of a thermally insulated compartment and a heat pump (mechanical, electronic, or chemical) that transfers heat from its inside to its external environment so that its inside is cooled to a temperature below the ambient temperature of the room. Refrigeration is an essential food storage technique around the world. The low temperature reduces the reproduction rate of bacteria, so the refrigerator lowers the rate of spoilage. A refrigerator maintains a temperature a few degrees above the freezing point of water. The optimal temperature range for perishable food storage is 3 to 5 °C (37 to 41 °F). A freezer is a specialized refrigerator, or portion of a refrigerator, that maintains its contents' temperature below the freezing point of water. The refrigerator replaced the icebox, which had been a common household appliance for almost a century and a half. The United States Food and Drug Administration recommends that the refrigerator be kept at or below 4 °C (40 °F) and that the freezer be regulated at −18 °C (0 °F). The first cooling systems for food involved ice. Artificial refrigeration began in the mid-1750s, and developed in the early 1800s. In 1834, the first working vapor-compression refrigeration system, using the same technology seen in air conditioners, was built. The first commercial ice-making machine was invented in 1854. In 1913, refrigerators for home use were invented. In 1923 Frigidaire introduced the first self-contained unit.
Since their establishment in 1952, Special Forces soldiers have operated in Vietnam, Cambodia, Laos, North Vietnam, Guatemala, Nicaragua, El Salvador, Colombia, Panama, Haiti, Somalia, Bosnia, Kosovo, 1st Gulf War, Afghanistan, Iraq, the Philippines, Syria, Yemen, Niger and, in an FID role, East Africa.
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。
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.