The short version of reversed-phase HPLC fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-15. Anything still debated is marked as such rather than presented as settled.
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。
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.
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.
| 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 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.
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.
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 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.
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.
As the manufacturing methods continue to evolve, vaccines with more complex constitutions will inevitably be generated in the future to extend their therapeutic applications to both infectious and non-infectious diseases, in order to safeguard the health of more people.
== Further reading == Bio-IT World a periodical covering glycomics Hirabayashi J, Arata Y, Kasai K (February 2001). "Glycome project: concept, strategy and preliminary application to Caenorhabditis elegans". Proteomics. 1 (2): 295–303. doi:10.1002/1615-9861(200102)1:2<295::AID-PROT295>3.0.CO;2-C. PMID 11680876. S2CID 42203562. (A proposal to base the glycome project on Caenorhabditis elegans, a microscopic worm, whose entire genome is already sequenced) 'GlycoChip' Carolyn Bertozzi's Seminar: "Chemical Glycobiology"
In the above equations, cE and cI are total concentrations of all polypeptides and all polynucleotides, φx and φy are dilution fluxes, ki is the production rate of polypeptide Ei translated from the polynucleotide Ii, and fi is the production rate of polynucleotide Ii synthesised by the complex IiEi-1 (through replication and polymerization). Coupling nucleic acids with proteins in such a model of hypercycle with translation demanded the proper model for the origin of translation code as a necessary condition for the origin of hypercycle organization. At the time of hypercycle theory formulation, two models for the origin of translation code were proposed by Crick and his collaborators. These were models stating that the first codons were constructed according to either an RRY or an RNY scheme, in which R stands for the purine base, Y for pyrimidine, and N for any base, with the latter assumed to be more reliable. Nowadays, it is assumed that the hypercycle model could be realized by utilization of ribozymes without the need for a hypercycle with translation, and there are many more theories about the origin of the genetic code.
Sources: en.wikipedia.org
== Clinical use == Metirosine has been shown to suppress catecholamine synthesis and alleviate symptoms related to catecholamine excess, including hypertension, headache, tachycardia, constipation, and tremor.
This competition could alter the post-transcriptional gene regulation (PTGR) of ADME-related genes, leading to indirect modulation of the expression of drug-metabolizing enzymes or transporters and causing DDIs with co-administered drugs. Short hairpin RNAs (shRNAs) may additionally compete with pre-miRNAs for the nuclear export protein Exportin-5 (XPO5) and the cytoplasmic ribonuclease Dicer, disrupting global miRNA biogenesis and posing further DDI risk. The U.S. Food and Drug Administration has issued guidance specific to oligonucleotide therapeutics, recommending assessment of QTc interval prolongation, immunogenicity, organ-impairment effects on PD endpoints, and the potential for RNAi machinery competition as part of the DDI risk framework for this drug class.
=== Cancer === It was first proposed by Otto Heinrich Warburg that cancer originated from irreversible injury to mitochondrial respiration, but the structural basis for this injury has remained elusive. Since cardiolipin is an important phospholipid found almost exclusively in the inner mitochondrial membrane and very essential in maintaining mitochondrial function, it is suggested that abnormalities in CL can impair mitochondrial function and bioenergetics. A study published in 2008 on mouse brain tumors supporting Warburg's cancer theory shows major abnormalities in CL content or composition in all tumors.
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。
Cold storage slows the chemical degradation reactions that occur in solution. Lyophilized powder is more stable than reconstituted liquid and tolerates longer storage periods. Repeated temperature cycling should still be avoided because it can drive aggregation and loss of material.