免疫调节 is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-05-25. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
The lyophilized peptide is generally stable for extended periods when kept cold and dry. Once dissolved, aqueous solutions are less stable; hydrolysis, oxidation, and aggregation can degrade the material. Storage at -20 °C or lower slows these processes. Repeated freeze-thaw cycles are best avoided because they can promote aggregation. The exact shelf life depends on formulation, pH, and concentration, so stability studies are typically performed for each specific product.
Quality control for thymosin alpha-1 focuses on identity, purity, and potency. Identity is confirmed by mass spectrometry and amino acid analysis, while purity is assessed by chromatography with limits on related substances and residual solvents. Potency assays may use cell-based immune readouts, but these are not standardized across laboratories. Regulatory status differs by jurisdiction; no product is approved in the United States for clinical use, whereas some other countries register injectable forms for specific indications.
| Property | Value | Notes |
|---|---|---|
| Molecular mass | ≈3,108 Da | Synthetic 28-residue peptide |
| Amino acid count | 28 | N-terminal serine carries an acetyl group |
| Appearance | White to off-white powder | Lyophilized solid |
| Water solubility | Freely soluble | Dissolves in aqueous buffer |
| Common synonyms | Thymalfasin; Tα1 | Thymalfasin is the international nonproprietary name |
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.
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.
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。
20 February Reg Douglas, Olympic rower (1956), British Empire and Commonwealth Games gold (1954, 1958) and silver medallist (1954) (born 1930). Sir Peter Trapski, lawyer and judge, chief District Court judge (1985–1989) (born 1935). Maata Wharehoka, weaver, Māori arts advocate, community leader (Parihaka), Ngā Tohu ā Tā Kīngi Īhaka (2015) (born 1950). 21 February – John Anderson, businessman, founder of Contiki Tours (1962) (born 1938). 24 February – Khalid Sandhu, Muslim community leader and physician, president of the Federation of Islamic Associations of New Zealand (1986–1988, 1989–1990) (born 1942). 27 February Dave Gillespie, rugby union player (Otago, Wellington, national team) (born 1934). Michael Moroney, Hall of Fame Thoroughbred racehorse trainer (Brew, Tofane, Xcellent) (born 1958).
=== Chiral crown ether === Chiral crown stationary phases consist Crown ethers, immobilized or bonded to the support particles, are polyethers with a macrocyclic structure that can create host-guest complexes with alkali, earth-alkali metal ions, and ammonium cations. The skeleton of the cyclic structure is composed of oxygen and methylene groups arranged alternately. The electron-donating ether oxygens are positioned within the inner wall of the crown cavity, and are encircled by methylene groups in a collar-like arrangement. The chiral recognition is based on two distinct diastereomeric inclusion complexes that can be generated. The primary interactions facilitating complexation involve hydrogen bonds, formed between the three amine hydrogens and the oxygens of the macrocyclic ether, arranged in a tripod configuration. Additionally, ionic interactions, dipole-dipole interactions, or hydrogen bonds can occur between the carbocyclic groups and polar groups of the analytes, providing further support for the complexes.
The Japanese Hisatugu Numata developed the first panoramic radiograph in 1933/34. This was followed by the development of intraoral panoramic X-ray units, in which the X-ray tube is placed intraorally (inside the mouth) and the X-ray film extraorally (outside the mouth). At the same time, Horst Beger from Dresden in 1943 and the Swiss dentist Walter Ott in 1946 worked on the Panoramix (Koch & Sterzel), Status X (Siemens) and Oralix (Philips). Intraoral panoramic devices were discontinued at the end of the 1980s because the radiation exposure was too high in direct contact with the tongue and oral mucosa due to the intraoral tube.
== Advantages and disadvantages == Advantages include minimal overlap in metal signals meaning the instrument is theoretically capable of detecting 100 parameters per cell, entire cell signaling networks can be inferred organically without reliance on prior knowledge, and one well-constructed experiment produces large amounts of data. Disadvantages, in the case of CyTOF, include the practical flow rate is around 500 cells per second versus several thousand in flow cytometry and current reagents available limit cytometer use to around 50 parameters per cell. Additionally, mass cytometry is a destructive method and cells cannot be sorted for further analysis. In the case of IMC, the resolution of the data is relatively low (1μm2/pixel), the technique is as well destructive, acquiring of the data is also very slow, and it requires specialized expensive equipment and expertise.
Sources: en.wikipedia.org
16 November – In a statement to the Scottish Parliament, Health Secretary Michael Matheson admits the cause of his £11,000 roaming charges bill came from his sons watching football on his parliamentary iPad while the family was on holiday in Morocco. Matheson confirms he has repaid the money and referred himself to the parliamentary watchdog. 17 November – A number of motorists have had their Glasgow Low Emission Zone fines cancelled after a tribunal ruled they were unenforceable due to a "procedural error" made by Glasgow City Council. The Scottish Government publishes its plans for European Union membership in an independent Scotland. 22 November – Petroineos announces to repurpose Grangemouth oil refinery, Scotland's only oil refinery, as a fuels import terminal with the loss of 400 jobs. The McDonald's fast food outlet in Fort William says it has had to ban under 18s from the premises after 6.00pm because of verbal abuse targeted at its staff. 23 November – The Scottish Parliament Corporate Body confirms it has launched an investigation into Health Secretary Michael Matheson's £11,000 data roaming bill. 24 November – Former First Minister Alex Salmond launches a fresh legal case against the Scottish Government over its mishandling of harassment allegations against him. Universities Scotland adopts a new policy that requires potential students offered a place at a university in Scotland to declare any charges for violent offences. 25 November – A police officer is taken to hospital after a civil disturbance breaks out in the East Ayrshire village of Auchinleck.
== A == Acetylcholine A neurotransmitter involved in muscle activation, attention, arousal, and memory. It acts at both nicotinic and muscarinic receptors throughout the central and peripheral nervous systems. Achromatopsia Loss of color vision as a result of damage to extrastriate visual cortex. Action Potential A rapid electrical signal that travels down the axon of a neuron. Activation The time-dependent opening of ion channels in response to a stimulus, typically membrane depolarization. Adaptation The phenomenon of sensory receptor adjustment to different levels of stimulation; critical for allowing sensory systems to operate over a wide dynamic range. Adenylyl cyclase Membrane-bound enzyme that can be activated by G-proteins to catalyze the synthesis of cyclic AMP from ATP. Adrenal cortex The outer region of the adrenal gland, responsible for producing steroid hormones such as cortisol and aldosterone, which regulate metabolism and stress responses. Adrenal medulla The central part of the adrenal gland that, under visceral motor stimulation, secretes epinephrine and norepinephrine into the bloodstream. Adrenaline See epinephrine. Afferent nerve fiber An axon that conducts action potentials from the periphery toward the central nervous system. Agnosia The inability to name objects, typically resulting from brain damage in the occipital or temporal lobes. Agonist A chemical that binds to and activates a receptor, mimicking the action of a natural neurotransmitter.
During the Allied occupation of Germany after World War II, internal borders were redrawn by the Allied military governments. New states were established in all four zones of occupation: Bremen, Hesse, Württemberg-Baden, and Bavaria in the American zone; Hamburg, Schleswig-Holstein, Lower Saxony, and North Rhine-Westphalia in the British zone; Rhineland-Palatinate, Baden, Württemberg-Hohenzollern and the Saarland – which later received a special status – in the French zone; Mecklenburg(-Vorpommern), Brandenburg, Saxony, Saxony-Anhalt, and Thuringia in the Soviet zone. No single state comprised more than 30% of either population or territory; this was intended to prevent any one state from being as dominant within Germany as Prussia had been in the past. Initially, only seven of the pre-War states remained: Baden (in part), Bavaria (reduced in size), Bremen, Hamburg, Hesse (enlarged), Saxony, and Thuringia. The states with hyphenated names, such as Rhineland-Palatinate, North Rhine-Westphalia, and Saxony-Anhalt, owed their existence to the occupation powers and were created out of mergers of former Prussian provinces and smaller states. Former German territory that lay east of the Oder-Neisse line fell under either Polish or Soviet administration but attempts were made at least symbolically not to abandon sovereignty well into the 1960s.
Despite challenges faced by the Pakistani film industry, Urdu televised dramas and theatrical performances remain popular, frequently broadcast by many entertainment media outlets. Urdu dramas dominate the television entertainment industry, renowned for their quality since the 1990s. Pakistani music encompasses diverse forms, from provincial folk music and traditional styles like Qawwali and Ghazal Gayaki to modern fusions of traditional and western music. Pakistan boasts numerous renowned folk singers, and the arrival of Afghan refugees in western provinces has sparked interest in Pashto music, despite occasional intolerance.
Homosildenafil (also known as methyl-sildenafil) is a synthetic drug which acts as a phosphodiesterase inhibitor. It is an analog of sildenafil and vardenafil. Homosildenafil was first identified as an adulterant in sex enhancement products in 2003 and was more recently detected in dietary supplements. Homosildenafil has 35% the PDE5 inhibition activity of sildenafil itself with similar selectivity. Sildenafil is mainly metabolized by the microsomal isozymes CYP3A4 with secondary metabolism by CYP2C9. The major active metabolite is N-desmethylsildenafil. The plasma level of the equivalent homosildenafil metabolite reaches 40% of sildenafil's bioavailability. The N-desmethyl metabolite is further metabolized, with a half-life of 4 hours.
Sources: en.wikipedia.org
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.
It is usually described as an immunomodulatory peptide rather than a classic hormone. It acts on immune cells through receptor pathways. No single endocrine organ target defines its function.
Several countries, including Italy and China, allow it for specific indications. The FDA has not approved it as a drug in the United States. Availability depends on local regulation.
Reverse-phase HPLC with ultraviolet detection at 214 nm is common. Mass spectrometry is used to confirm molecular identity and detect modifications. Immunoassays exist but may not distinguish the intact peptide from fragments.