This is a working overview of 免疫调节, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-11-17 and is reviewed periodically as new material appears.
Recommended storage for the dry powder is a freezer near minus twenty degrees Celsius, kept desiccated and away from light. Once dissolved, the peptide is less stable and is usually held at two to eight degrees Celsius for short intervals or frozen for longer storage. Stability studies focus on the acetylated terminus and the disulfide linkage because those features define the intact molecule. Common degradation routes include cysteine oxidation, deamidation of asparagine or glutamine side chains, and slow formation of higher-molecular-weight species.
Identity and purity are usually checked by reverse-phase high-performance liquid chromatography, which separates the intact chain from truncated products, together with mass spectrometry for confirmation of the expected mass. Peptide mapping after enzymatic digestion and amino acid analysis add sequence-level evidence. Release testing also covers water content, residual solvents, and counter-ions, all of which influence measured mass and stability. Related-peptide limits are commonly expressed as a percentage of total peak area, with individual unspecified impurities held below a lower threshold.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Assessed by visual inspection at release |
| Solubility class | Freely soluble in water | Aqueous buffers near neutral pH |
| Typical storage temperature | Minus 20 degrees Celsius | Lyophilized, desiccated, protected from light |
| Typical analytical method | Reverse-phase HPLC with mass spectrometry | Used together for purity and identity |
| Common synonyms | T-alpha-1; thymalfasin | Older reports use several designations |
临床研究将Tα1用于慢性病毒感染、肿瘤辅助治疗和疫苗佐剂等场景。部分试验报告了免疫学指标改善，但临床终点获益在不同研究中并不一致。系统综述指出，研究间在人群、剂量和联合方案上差异较大，难以汇总结论。因此，Tα1的确切临床地位仍属开放问题，需要更多高质量随机对照试验来澄清。其机制研究也需从体外实验向体内模型推进。
胸腺素α1对免疫系统的影响涉及多种细胞类型。研究表明，它可促进未成熟T细胞向成熟T细胞分化，并增强T细胞对抗原刺激的增殖反应。树突状细胞在Tα1存在下表达更高水平的共刺激分子，从而更有效地呈递抗原。此外，自然杀伤细胞的活性也观察到上升。这些效应并非直接杀伤病原体，而是调节宿主免疫应答的强度与方向。
Overall evidence quality varies considerably. A large share of published reports come from single centers, rely on surrogate immunological markers, or lack adequate control groups. Systematic reviews have highlighted this heterogeneity as a barrier to pooling results. Open questions include which patients, if any, might benefit, what treatment duration is appropriate, and whether any effect is independent of standard care. The peptide is often described as an immune modulator rather than a therapy for one disease, which complicates confirmatory trial design.
Thymosin alpha 1 was identified in 1977 as a component of thymosin fraction 5, a heterogeneous preparation used in early studies of thymic function. Investigators purified the active material and determined its amino acid sequence, which enabled chemical synthesis. Work in the following decades concentrated on T-cell maturation and immune reconstitution in animals and small human cohorts. Early preparations varied in composition, so results from that period are difficult to compare with studies using defined synthetic peptide.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
=== Production === It is traditionally obtained by hydrolysis of various sources of protein, such as gelatin. It is obtained commercially by fermentation. In this way, 25-35 g/liter can be produced, using glucose as a carbon source.
== Further reading == Beardsley, E. (2006). "The Spartanburg Pellagra Hospital". The South Carolina Encyclopedia. Columbia, South Carolina: University of South Carolina Press. ISBN 1-57003-598-9. Crabb, Mary Katherine (1992). "An Epidemic of Pride: Pellagra and the Culture of the American South". Anthropologica. 34 (1): 89–103. doi:10.2307/25605634. JSTOR 25605634. Hampl, J. S.; Hampl, W. S. (1 November 1997). "Pellagra and the origin of a myth: evidence from European literature and folklore". Journal of the Royal Society of Medicine. 90 (11): 636–39. doi:10.1177/014107689709001114. PMC 1296679. PMID 9496281. Hendrick, Burton J. (April 1916). "The Mastery of Pellagra: The Mysterious Disease, Almost Unknown in This Country Fifteen Years Ago, That Now Claims 7,500 Victims A Year And Is Spreading Rapidly". The World's Work: A History of Our Time. XXXI: 633–39. Kraut, Alan (3 September 2010). "Dr. Joseph Goldberger and the War on Pellagra". Office of NIH History. National Institutes of Health. Archived from the original on 22 October 2004. "Reports and Resolutions of the General Assembly of the State of South Carolina, Regular Session Commencing January 11, 1916". Annual Report of the State Board of Health (1915–1916). 4. Columbia, South Carolina: Gonzales and Bryan, state printers. 1916. Swain, C. P.; Tavill, A. S.; Neale, G. (September 1976). "Studies of tryptophan and albumin metabolism in a patient with carcinoid syndrome, pellagra, and hypoproteinemia". Gastroenterology. 71 (3): 484–89. doi:10.1016/s0016-5085(76)80460-x. PMID 133045.
Pharmaceutical agents that will alter the natural history of disease progression by arresting joint structural change and ameliorating symptoms are termed as disease modifying therapy. Therapies under investigation include the following:
=== Peanut butter allergy === In 2016, a lawsuit was filed after an employee at a Natick, Massachusetts, store put peanut butter on a sandwich, despite being informed that the person receiving the sandwich had a peanut allergy. The plaintiffs charged the company and those employees involved with intentional infliction of emotional distress and negligent infliction of emotional distress, as well as assault and battery. The recipient of the sandwich was hospitalized briefly.
== Toxicokinetics == The kinetics of labeled derivatives of apamin were studied in vitro and in vivo in mice by Cheng-Raude et al. This shed some light on the kinetics of apamin itself. The key organ for excretion is likely to be the kidney, since enrichment of the labeled derivatives was found there. The peptide apamin is small enough to pass the glomerular barrier, facilitating renal excretion. The central nervous system, contrarily, was found to contain only very small amounts of apamin. This is unexpected, as this is the target organ for neurotoxicity caused by apamin. This low concentration thus appeared to be sufficient to cause the toxic effects. However, these results disagree with a study of Vincent et al. After injection of a supralethal dose of radioactive acetylated apamin in mice, enrichment was found in the spinal cord, which is part of the target organ. Some other organs, including kidney and brain, contained only small amounts of the apamin derivative.
Sources: en.wikipedia.org
=== Preparation of acyl cyanides === Acyl cyanides (α-oxonitriles) can in certain cases be prepared by reacting carboxylic acid halides with transition metal cyanides (e.g., copper cyanide or silver cyanide). This approach is particularly effective for aromatic carboxylic acid halides and aliphatic acyl bromides, whereas aliphatic acyl chlorides are unreactive. Aliphatic acyl cyanides can instead be synthesized by reacting carboxylic acid chlorides with trimethylsilyl cyanide.
== Factors affecting topical drug absorption == Topical drug absorption depends on two major factors – biological and physicochemical properties. The first factor concerns body structure effects on the drugs. The degradation of drugs can be affected by the site of applications. Some studies discovered different percutaneous absorption patterns. Apart from the place, age also affects the absorption as the skin structure changes with age. The lowered collagen and broadened blood capillary networks happen with aging. These features alter the effectiveness of absorption of both hydrophilic and lipophilic substances into stratum corneum underneath the surface of the skin. The skin surface integrity can also affect the permeability of drugs such as the density of hair follicles, sweat glands or disintegrated by inflammation or dehydration. The other factor concerns metabolism of medications on skin. When the percutaneous drug is applied on skin, it will be gradually absorbed down the skin. Normally, when the drugs are absorbed, they will be metabolised by various enzymes in our body and the amount will be lower. The exact amount delivered to the target action site determines the potency and bioavailability of the drugs. If the concentration is too low, the therapeutic effect is impeded; if the concentration is too high, drug toxicity may happen to cause side effects or even do harm to our body. For the topical drug delivery way, degradation of drugs in skin is very low compared to liver.
== Risks == The risk of complications of the surgical wound is greater for those greater than 65-years-old, or who have pulmonary disease, nutritional deficiencies, overweight, other illnesses and high blood pressure.
== Background == The World Health Organization has declared that finding where SARS-CoV-2 came from is a priority and that it is "essential for understanding how the pandemic started". In May 2020, the World Health Assembly, which governs the World Health Organization (WHO), passed a motion calling for a "comprehensive, independent and impartial" study into the COVID-19 pandemic. A record 137 countries, including China, co-sponsored the motion, giving overwhelming international endorsement to the study. In mid 2020, the World Health Organization (WHO) began negotiations with the government of China on conducting an official study into the origins of COVID-19. In November 2020, the WHO published a two-phase study plan. The purpose of the first phase was to better understand how the virus "might have started circulating in Wuhan", and a second phase involves longer-term studies based on the findings of the first phase. WHO director-general Tedros Adhanom said "We need to know the origin of this virus because it can help us to prevent future outbreaks," adding, "There is nothing to hide. We want to know the origin, and that's it." He also urged countries not to politicise the origin tracing process, saying that would only create barriers to learning the truth.
Dr. Reddy's originally launched in 1984 producing active pharmaceutical ingredients. In 1986, Reddy's started operations on branded formulations. Within a year Reddy's had launched Norilet, the company's first recognised brand in India. Soon, Dr. Reddy's obtained another success with Omez, its branded omeprazole – gastrointestinal ulcer and reflux oesophagitis medication – launched at half the price of other brands on the Indian market at that time. Within a year, Reddy's became the first Indian company to export the active ingredients for pharmaceuticals to Europe. In 1987, Reddy's started to transform itself from a supplier of pharmaceutical ingredients to other manufacturers into a manufacturer of pharmaceutical products. In 1999, Dr. Reddy's joined the Indian Pharmaceutical Alliance as a founding member in an effort to promote the development of generic drugs in India.
Sources: en.wikipedia.org
Reconstituted solutions are typically kept refrigerated at two to eight degrees Celsius when used within a short window, or frozen in aliquots for longer periods. Repeated freeze-thaw cycles are avoided because they can reduce recovery of intact peptide.
It establishes that the measured mass matches the expected value for the intact molecule. It also helps detect modifications such as oxidation or truncation that shift the mass by a known amount.
Cycling between frozen and liquid states can promote aggregation and adsorption to container walls. Dividing a stock into single-use aliquots limits the number of cycles a given vial undergoes.
It is a chain of 28 amino acids, with an acetyl group attached to the first serine residue. The synthetic version replicates this sequence. Its molecular mass is about 3,108 daltons.