胸腺素α1 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-07-25 and is reviewed periodically as new material appears.
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.
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.
Thymosin alpha-1 is a synthetic peptide of 28 amino acids, corresponding to the N-terminal fragment of prothymosin alpha. Its sequence begins with acetylation at the N-terminus, a modification that affects stability and receptor interaction. The peptide is acidic, with a calculated isoelectric point near 4.2, and carries no disulfide bonds, so its secondary structure is largely flexible in solution. Molecular mass is approximately 3108 daltons. The native form was first isolated from bovine thymus tissue, while pharmaceutical material is produced by solid-phase peptide synthesis.
| Property | Value | Notes |
|---|---|---|
| Molecular mass | About 3.1 kDa | 28 residues, N-terminally acetylated |
| Appearance | White to off-white powder | Lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in aqueous buffers |
| Storage temperature | 2 to 8 °C | Protect from light and moisture |
| Common synonyms | Thymalfasin; Tα1 | Same peptide sequence |
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 synthetic 28-amino-acid peptide whose sequence was first identified in extracts of bovine thymus tissue during the 1970s. The chain carries an acetyl group on its N-terminal serine. Its acidic residue content is high, which produces strong water solubility and an isoelectric point well below neutrality. Material supplied for laboratory and clinical use is manufactured by solid-phase peptide synthesis rather than purified from animal tissue. Different salt forms, such as the acetate, alter the counter-ion content without changing the peptide backbone.
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.
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。
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.
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.
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.
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.
== Bibliography == Prentice, B. E., & Benell, D. (1992). "Determinants of empty returns by US refrigerated trucks: conjoint analysis approach". Canadian Journal of Agricultural Economics/Revue canadienne d'agroeconomie, 40(1), 109-127. doi:10.1111/j.1744-7976.1992.tb03680.x (abstract).
Although India possessed nuclear weapons at the time and was not a party to the Nuclear Non-Proliferation Treaty, it received waivers from the International Atomic Energy Agency and the Nuclear Suppliers Group, ending earlier restrictions on India's nuclear technology and commerce; India subsequently signed co-operation agreements involving civilian nuclear energy with Russia, France, the United Kingdom, and Canada.
=== Spinal nerves === A goal of spinal cord injury research is to promote neuroregeneration, reconnection of damaged neural circuits. The nerves in the spine are a tissue that requires a stem cell population to regenerate. In 2012, a Polish fireman Darek Fidyka, with paraplegia of the spinal cord, underwent a procedure, which involved extracting olfactory ensheathing cells (OECs) from Fidyka's olfactory bulbs, and injecting these stem cells, in vivo, into the site of the previous injury. Fidyka eventually gained feeling, movement and sensation in his limbs, especially on the side where the stem cells were injected; he also reported gaining sexual function. Fidyka can now drive and can now walk some distance aided by a frame. He is believed to be the first person in the world to recover sensory function from a complete severing of the spinal nerves.
=== International consumption === While less common globally due to safety concerns, TKG is gaining recognition internationally. Tourists visiting Japan often try it, and Japanese eggs produced under high hygiene standards are exported to places like Hong Kong and Singapore. Some countries have traditional dishes involving raw egg, such as steak tartare (Europe) and yukhoe (Korea).
Sources: en.wikipedia.org
It is recommended that at least two sets are collected from two separate venipuncture locations. This helps to distinguish infection from contamination, as contaminants are less likely to appear in more than one set than true pathogens. Additionally, the collection of larger volumes of blood increases the likelihood that microorganisms will be detected if present. Blood culture bottles contain a growth medium, which encourages microorganisms to multiply, and an anticoagulant that prevents blood from clotting. Sodium polyanethol sulfonate (SPS) is the most commonly used anticoagulant because it does not interfere with the growth of most organisms. The exact composition of the growth medium varies, but aerobic bottles use a broth that is enriched with nutrients, such as brain-heart infusion or trypticase soy broth, and anaerobic bottles typically contain a reducing agent such as thioglycollate. The empty space in an anaerobic bottle is filled with a gas mixture that does not contain oxygen. Many commercially manufactured bottles contain a resin that absorbs antibiotics to reduce their action on the microorganisms in the sample. Bottles intended for paediatric use are designed to accommodate lower blood volumes and have additives that enhance the growth of pathogens more commonly found in children. Other specialized bottles may be used to detect fungi and mycobacteria. In low and middle income countries, pre-formulated culture bottles can be prohibitively expensive, and it may be necessary to prepare the bottles manually.
Spray ionization methods involve the formation of aerosol particles from a liquid solution and the formation of bare ions after solvent evaporation. Solvent-assisted ionization (SAI) is a method in which charged droplets are produced by introducing a solution containing analyte into a heated inlet tube of an atmospheric pressure ionization mass spectrometer. Just as in Electrospray Ionization (ESI), desolvation of the charged droplets produces multiply charged analyte ions. Volatile and nonvolatile compounds are analyzed by SAI, and high voltage is not required to achieve sensitivity comparable to ESI. Application of a voltage to the solution entering the hot inlet through a zero dead volume fitting connected to fused silica tubing produces ESI-like mass spectra, but with higher sensitivity. The inlet tube to the mass spectrometer becomes the ion source.
==== Section A: Cryogenics and Liquefied Gases ==== Section A on Cryogenics and Liquefied Gases focuses on refrigeration science and technology at low temperatures: the cryogenic domain spans the lower part of the temperature scale, from absolute zero to 120 K, thus encompassing the normal boiling points of air gases as well as of liquid natural gas (LNG). Section A comprises two Commissions, A1 Cryophysics and Cryoengineering, and A2 Liquefaction and Separation of Gases. Commission A1 deals with research, development and industrial activities at the lowest temperatures, including low-temperature physics, applications of superconductivity and helium cryogenics. Commission A2 essentially covers the liquefied gas industry, including air separation and LNG technology, two mature domains with high economic stakes and ongoing developments addressing important societal issues such as energy efficiency and carbon sequestration. Section A also maintains and develops relations with other Sections of the IIR, mainly Commission B1 Thermodynamics and Transfer Processes in the field of thermodynamics and transfer processes, essential tools of the cryogenic engineer, and Commission C1 Cryobiology, Cryomedicine and Health Products for the cooling of biological specimens and living tissues for preservation or treatment, which require implementing cryogenic processes.
Charcuterie – the branch of cooking devoted to prepared meat products, such as bacon, ham, sausage, terrines, galantines, pâtés, and confit, primarily from pork. Charcuterie is part of the garde manger chef's repertoire. Originally intended as a way to preserve meat before the advent of refrigeration, they are prepared today for their flavors derived from the preservation processes. Charque – a form of jerky common in South America made from dried and salted meat, originally llama where this animal roamed, but nowadays mostly beef. Chinese sausage – a generic term referring to the many different types of sausages originating in China. Chipped beef – thinly sliced or pressed salted and dried beef. Some varieties are smoked to add flavor. Chorizo – can be a fresh sausage, in which case it must be cooked before eating. In Europe, it is more frequently a fermented, salt-cured, smoked sausage Cold cut – precooked or cured meat, including dried sausages. Country ham – a variety of cured ham that is typically very salty. Country hams are salt-cured (and occasionally nitrite- and nitrate-cured) for one to three months. Culatello – a refined variety of prosciutto, made from heavier pigs, cut to a fraction of the normal prosciutto and aged, and may be cured with wine, with culatello di Zibello having PDO status.
== Description == Tulips are perennial herbaceous bulbiferous geophytes that bloom in spring and die back after flowering to an underground storage bulb. A bulb can be as much as 5 cm (2 inches) in diameter or as small as 1 cm (0.4 in). Tulip stems have few leaves. Larger species tend to have multiple leaves. Plants typically have two to six leaves, some species up to 12. The tulip's leaf is cauline (born on a stem), strap-shaped, with a waxy coating, and the leaves are alternate (alternately arranged on the stem), diminishing in size the further up the stem. These fleshy blades are often bluish-green in colour. The bulbs are truncated basally and elongated towards the apex. They are covered by a protective tunic (tunicate) which can be glabrous or hairy inside. Depending on the species, tulip leaves are typically 10 and 25 cm (4 and 10 inches) long, but in some species reach over 30 cm (12 in).
Sources: en.wikipedia.org
These cells generate action potentials that propagate down axons to the nerve endings in the pituitary; the endings contain large numbers of oxytocin-containing vesicles, which are released by exocytosis when the nerve terminals are depolarised.
Silica coatings increase the external surface area to assist in binding and are heat resistant. There are various coatings used to prevent leaching of the magnetic core of the nanoparticles; these coatings have a significant salt concentration with a slightly alkaline (basic) pH. Polyethylene glycol (PEG) is an example of a hydrophilic coating that has been used as a biocompatible targeting modality. Hydrophilic PEG interacts beneficially with the physiological environment to improve biocompatibility by preventing opsonization on the surface of the particles, thus increasing circulation time from minutes to hours, or even days, for magnetic nanoparticles. MRI shows prolonged PEG circulation and increased SPIO-PEG-D particle accumulation within the tumor with magnetic guidance. Coating not only provides hydrophilic and hydrophobic properties but can also contribute to temperature- and pH-dependent properties. Particular substances, such as PNG, provide these two properties, allowing unique and efficient delivery of drugs. This also enables greater control of release, as body temperature allows a greater amount of drug released, while physiological pH allows a lower amount of drug released. Other coating options for similar pH-dependent properties include the hydrogel chitosan that is crosslinked to a polymer coating. These coating choices have displayed positive results in delivery of anticancer drugs.
== References == Carpenter, Kenneth (1999). Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past), Indiana University Press; ISBN 0-253-33497-7. Deeming, D. C. and M. W. J. Ferguson (eds.) 1991. Egg incubation: its effect on embryonic development in birds and reptiles. Cambridge University Press, UK. 448pp. Glut, Donald F. (2003), "Appendix: Dinosaur Tracks and Eggs", Dinosaurs: The Encyclopedia. 3rd Supplement, Jefferson, North Carolina: McFarland & Company, Inc., pp. 613–652, ISBN 978-0-7864-1166-5 Horner, John R.; Weishampel, David B. (1996). "A comparative embryological study of two ornithischian dinosaurs - a correction". Nature. 383 (6595): 256–257. Bibcode:1996Natur.383..103H. doi:10.1038/383103b0. Mateus, I; Mateus, H; Antunes, MT; Mateus, O; Taquet, P; Ribeiro, V; Manuppella, G (1998). "Upper Jurassic theropod dinosaur embryos from Lourinhã (Portugal)". Memórias da Academia das Ciências de Lisboa. 37: 101–110. Moskvitch, Katia. "Eggs with the Oldest Known Embryos of a Dinosaur Found". BBC News. November 12, 2010. de Ricqlès, A.; Mateus, O.; Antunes, M. T.; Taquet, P. (2001). "Histomorphogenesis of embryos of Upper Jurassic theropods from Lourinhã (Portugal)". Comptes Rendus de l'Académie des Sciences, Série IIA. 332 (10): 647–656. Bibcode:2001CRASE.332..647D. doi:10.1016/s1251-8050(01)01580-4. Reisz, Robert R.; Scott, Diane; Sues, Hans-Dieter; Evans, David C.; Raath, Michael A. (2005). "Embryos of an Early Jurassic prosauropod dinosaur and their evolutionary significance" (PDF). Science. 309 (5735): 761–764.
In January 1977, four years prior to becoming president, Ronald Reagan bluntly stated, in a conversation with Richard V. Allen, his basic expectation in relation to the Cold War. "My idea of American policy toward the Soviet Union is simple, and some would say simplistic," he said. "It is this: We win and they lose." In 1980, Ronald Reagan won the 1980 presidential election, vowing to increase military spending and confront the Soviets everywhere. Both Reagan and new British Prime Minister Margaret Thatcher denounced the Soviet Union and its ideology. Reagan labeled the Soviet Union an "evil empire" and predicted that communism would be left on the "ash heap of history," while Thatcher inculpated the Soviets as "bent on world dominance." In 1982, Reagan tried to cut off Moscow's access to hard currency by impeding its proposed gas line to Western Europe. It hurt the Soviet economy, but it also caused ill will among American allies in Europe who counted on that revenue. Reagan retreated on this issue. By early 1985, Reagan's anti-communist position had developed into a stance known as the new Reagan Doctrine—which, in addition to containment, formulated an additional right to subvert existing communist governments. Besides continuing Carter's policy of supporting the Islamic opponents of the Soviet Union and the Soviet-backed PDPA government in Afghanistan, the CIA also sought to weaken the Soviet Union itself by promoting Islamism in the majority-Muslim Central Asian Soviet Union.
That rate differs between cells of differing size and water permeability: a typical cooling rate of about 1 °C/minute is appropriate for many mammalian cells after treatment with cryoprotectants such as glycerol or dimethyl sulfoxide (DMSO), but the rate is not a universal optimum. The 1 °C / minute rate can be achieved by using devices such as a rate-controlled freezer or a benchtop portable freezing container. Several independent studies have provided evidence that frozen embryos stored using slow-freezing techniques may in some ways be 'better' than fresh in IVF. The studies indicate that using frozen embryos and eggs rather than fresh embryos and eggs reduced the risk of stillbirth and premature delivery though the exact reasons are still being explored.
Sources: en.wikipedia.org
It is a 28-residue synthetic peptide studied as an immune-modulating agent and approved as a drug in some countries. The sequence matches a naturally occurring fragment isolated from thymus tissue. It is not a hormone in the endocrine sense.
The name traces back to thymosin fraction 5, a crude thymus extract examined in the 1970s. Individual peptides in that mixture were labeled with Greek letters, and alpha-1 was one of them. The international nonproprietary name thymalfasin was assigned later.
No. Thymosin beta-4 contains 43 residues and binds actin, while thymosin alpha-1 contains 28 residues and acts on immune cells. The two sit in a historical naming group but share no sequence similarity, and they are not substitutes for one another.
It corresponds to a fragment of the larger protein prothymosin alpha, which is present in many tissues. The isolated 28-amino-acid peptide was originally obtained from thymus preparations, and the pharmaceutical product is synthesized rather than extracted. The term therefore describes both a natural fragment and a manufactured drug substance.