免疫组织 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2025-08-28. Anything still debated is marked as such rather than presented as settled.
Thymosin beta-4 is a separate 43-residue peptide that binds actin and participates in cell migration; it shares no sequence similarity with thymosin alpha-1 despite the common family name. Other preparative materials, such as thymosin fraction 5 and thymopoietin, contain distinct mixtures or peptides. The shared thymosin label reflects the tissue of origin used in early purification, not a common structural core. Treating these molecules as interchangeable is a frequent source of confusion in laboratory reports and in popular summaries alike.
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.
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.
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.
| 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 |
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。
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.
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.
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.
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.
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.
=== United Kingdom === Following fears of variant Creutzfeldt–Jakob disease (vCJD) being spread through the blood supply, the British government began to phase out blood plasma from U.K. donors and by the end of 1999 had imported all blood products made with plasma from the United States. In 2002, the British government purchased Life Resources Incorporated, an American blood supply company, to import plasma. The company became Plasma Resources UK (PRUK) which owned Bio Products Laboratory. In 2013, the British government sold an 80% stake in PRUK to American hedge fund Bain Capital, in a deal estimated to be worth £200 million. The sale was met with criticism in the UK. In 2009, the U.K. stopped importing plasma from the United States, as it was no longer a viable option due to regulatory and jurisdictional challenges. At present (2024), blood donated in the United Kingdom is used by UK Blood Services for the manufacture of plasma blood components (Fresh Frozen Plasma (FFP) and cryoprecipitate). As of 2025, NHS patients have received medicines made from plasma and blood donors in England.
It has been suggested that the main role of leptin is to act as a starvation signal when levels are low, to help maintain fat stores for survival during times of starvation, rather than a satiety signal to prevent overeating. Leptin levels signal when an animal has enough stored energy to spend it in pursuits besides acquiring food. This would mean that leptin resistance in obese people is a normal part of mammalian physiology and possibly, could confer a survival advantage. Leptin resistance (in combination with insulin resistance and weight gain) is seen in rats after they are given unlimited access to palatable, energy-dense foods. This effect is reversed when the animals are put back on a low-energy diet. This also may have an evolutionary advantage: allowing energy to be stored efficiently when food is plentiful would be advantageous in populations where food frequently may be scarce. A fad diet, the Rosedale diet is based on ideas about how leptin might affect weight. It is based on unsound science and marketed with unevidenced claims of health benefits.
The use of basic technology is also a feature of nonhuman animal species. Tool use was once considered a defining characteristic of the genus Homo. This view was supplanted after discovering evidence of tool use among chimpanzees and other primates, dolphins, and crows. For example, researchers have observed wild chimpanzees using basic foraging tools, pestles, levers, leaves as sponges, and tree bark or vines as probes to fish termites. Western chimpanzees use stone hammers and anvils for cracking nuts, as do capuchin monkeys of Boa Vista, Brazil. Tool use is not the only form of animal technology use; for example, beaver dams, built with wooden sticks or large stones, are a technology with "dramatic" impacts on river habitats and ecosystems.
Albany calls itself the "rare metals capital of the world", producing zirconium, hafnium and titanium. One of the major producers of these metals in Albany is ATI Specialty Alloys and Components (formerly ATI Wah Chang) which has a 110-acre (0.45 km2) site that primarily focuses on the production of zirconium. Albany and the surrounding communities are major exporters of grass seed. Other crops produced include corn, beans, mint, strawberries, and hazelnuts. Linn County is also referred to as the "Grass Seed Capital of the World". Albany is the headquarters of Coastal Farm & Ranch, a chain of farm supply stores in the Pacific Northwest. The decline of the timber industry and the outsourcing of manufacturing jobs has left Linn County with a relatively high unemployment rate. The Oregon Employment Department does not maintain unemployment statistics for cities. The losses in the timber industry in the region around Albany have led the city to a more diverse economic base for the city, led by retail trade, health care and social assistance, and manufacturing as the three leading aspects of the economy. Oregon Freeze Dry is a leading employer in the manufacturing sector of the Albany economy with its headquarters located in the city. The company employs over 300 people and was incorporated in 1963.
Sources: en.wikipedia.org
=== Blood symptoms === The characteristic hematological (blood) effects of copper deficiency are anemia (which may be microcytic, normocytic or macrocytic) and neutropenia. Thrombocytopenia (low blood platelets) is unusual. The peripheral blood and bone marrow aspirate findings in copper deficiency can mimic myelodysplastic syndrome. Bone marrow aspirate in both conditions may show dysplasia of blood cell precursors and the presence of ring sideroblasts (erythroblasts containing multiple iron granules around the nucleus). Unlike most cases of myelodysplastic syndrome, the bone marrow aspirate in copper deficiency characteristically shows cytoplasmic vacuoles within red and white cell precursors, and karyotyping in cases of copper deficiency does not reveal cytogenetic features characteristic of myelodysplastic syndrome. Anemia and neutropenia typically resolve within six weeks of copper replacement.
The Houthis began protesting against Hadi's government to demand concessions in order to resolve a years-long insurgency they had been waging against the Yemeni state in mid-2014. The uprising escalated dramatically as Houthi fighters swept into Sanaa, the capital, and effectively seized control of the city from the Yemeni military within a couple of days in September. The forces of General Ali Mohsen al-Ahmer surrendered to the Houthis after a brief fight. Ali Abdullah Saleh, the former president, was widely suspected of aiding the Houthis behind the scenes and helping pave the way for their takeover. Prime Minister Mohammed Basindawa resigned on 21 September as part of a deal meant to end the standoff.
== Measurement == Follicle-stimulating hormone is typically measured in the early follicular phase of the menstrual cycle, typically day three to five, counted from last menstruation. At this time, the levels of estradiol (E2) and progesterone are at the lowest point of the menstrual cycle. FSH levels in this time is often called basal FSH levels, to distinguish from the increased levels when approaching ovulation. FSH is measured in international units (IU). For Human Urinary FSH, one IU is defined as the amount of FSH that has an activity corresponding to 0.11388 mg of pure Human Urinary FSH. For recombinant FSH, one IU corresponds to approximately 0.065 to 0.075 μg of a "fill-by-mass" product. The mean values for women before ovulation are around (3.8-8.8) IU/L. After ovulation these levels drop to between (1.8-5.1) IU/L. At the mid of the menstrual cycle it reaches its highest value, between (4.5-22.5) IU/L. During menopause, the values goes up even more, between (16.74-113.59) IU/L. For men, the mean values are around (1.5-12.4) IU/L.
As an ointment, tacrolimus is used in the treatment of dermatitis (eczema), in particular atopic dermatitis, if topical corticosteroids and moisturisers fail in helping. It suppresses inflammation in a similar way to steroids, and is equally as effective as a mid-potency steroid. An important advantage of tacrolimus is that, unlike steroids, it does not cause skin thinning (atrophy), or other steroid related side effects. It is applied on the active lesions until they heal off, but may also be used continuously in low doses (twice a week), and applied to the thinner skin over the face and eyelids. Clinical trials of up to one year have been conducted. Recently it has also been used to treat segmental vitiligo in children, especially in areas on the face.
Wingstop opened its first international restaurant in Mexico in 2010. In April 2013, Wingstop announced that they are opening the first store in Southeast Asia, starting in Singapore. In February 2014, Wingstop announced the opening of stores in the Philippines. The first Philippine store opened in June 2014. In the same month, plans were announced for Wingstop to open in Indonesia with 100 stores by 2021. Franchises began opening in London, UK in 2018 and have now grown to 20 locations in the Greater London area. Originally introduced to England by Lemon Pepper Holdings, the majority stakeholder in the franchise is now Sixth Street Partners - the same investment firm that owns the Far West Services franchises on the US West Coast. In 2021, Wingstop made an agreement with JPK Capital to develop 100 Wingstop locations in Canada. The first restaurant in Canada opened in June 2022. In May 2022, Wingstop announced plans to enter South Korea. As of November 26, 2025, Wingstop operates in 15 countries internationally. Recent expansions include Australia, Bahrain, Kuwait, Puerto Rico, Saudi Arabia, and the Netherlands. On this same day, Wingstop reiterated its intentions to expand into Thailand, Italy and Ireland. The first Wingstop in Australia opened on May 17, 2025. The first Dutch outlet opened on August 8 2025, at Amsterdam Airport Schiphol. The first Irish outlet on December 8, 2025 at Dublin's Liffey Valley shopping centre. On December 13, 2025, Wingstop entered the Thailand market, in MBK Center.
Sources: en.wikipedia.org
=== Space exploration === A direct search for life in Europa's ocean would today be prohibitively expensive. Impacts on Europa give us an easier way to look for evidence of life there. Every time a major impact occurs on Europa, a vast quantity of water is splashed from the ocean into the space around Jupiter. Some of the water evaporates, and some condenses into snow. Creatures living in the water far enough from the impact have a chance of being splashed intact into space and quickly freeze-dried. Therefore, an easy way to look for evidence of life in Europa's ocean is to look for freeze-dried fish in the ring of space debris orbiting Jupiter. Freeze-dried fish orbiting Jupiter is a fanciful notion, but nature in the biological realm has a tendency to be fanciful. Nature is usually more imaginative than we are. ...To have the best chance of success, we should keep our eyes open for all possibilities.
=== Resolution === Resolution of DKA is defined as the general improvement in the symptoms, such as the ability to tolerate oral nutrition and fluids, normalization of blood acidity (pH>7.3), and absence of ketones in the blood (<1 mmol/L) or urine. Once this has been achieved, insulin may be switched to the usual subcutaneously administered regimen, one hour after which the intravenous administration can be discontinued. In people with suspected ketosis-prone type 2 diabetes, determination of antibodies against glutamic acid decarboxylase and islet cells may aid in the decision whether to continue insulin administration long-term (if antibodies are detected), or whether to withdraw insulin and attempt treatment with oral medication as in type 2 diabetes. Generally speaking, routine measurement of C-peptide as a measure of insulin production is not recommended unless there is genuine doubt as to whether someone has type 1 or type 2 diabetes.
=== Degradation === In mammals, norepinephrine is rapidly degraded to various metabolites. The initial step in the breakdown can be catalyzed by either of the enzymes monoamine oxidase (mainly monoamine oxidase A) or COMT. From there, the breakdown can proceed by a variety of pathways. The principal end products are either Vanillylmandelic acid or a conjugated form of MHPG, both of which are thought to be biologically inactive and are excreted in the urine.
PEGylation is the process of attaching the strands of the polymer PEG to molecules, most typically peptides, proteins, and antibody fragments, that can improve the safety and efficiency of many therapeutics. It produces alterations in the physiochemical properties including changes in conformation, electrostatic binding, hydrophobicity etc. These physical and chemical changes increase systemic retention of the therapeutic agent. Also, it can influence the binding affinity of the therapeutic moiety to the cell receptors and can alter the absorption and distribution patterns. PEGylation, by increasing the molecular weight of a molecule, can impart several significant pharmacological advantages over the unmodified form, such as improved drug solubility, reduced dosage frequency with potentially reduced toxicity and without diminished efficacy, extended circulating life, increased drug stability, and enhanced protection from proteolytic degradation; PEGylated forms may also be eligible for patent protection.
==== Elicitors ==== Pst DC3000 produces a PsINF1, the INF1 in P. syringae. Hosts respond with autophagy upon detection of this elicitor. Liu et al. 2005 finds this to be the only alternative to mass hypersensitivity leading to mass programmed cell death.
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 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.