Everything below concerns prothymosin alpha. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-12-06. Numbers and descriptions here follow the published literature rather than marketing material.
Lyophilized thymosin alpha 1 is typically stored refrigerated at 2 to 8 degrees Celsius and kept away from light. Reconstituted solutions are less stable and are usually used promptly after preparation. Repeated freeze-thaw cycles are avoided because they can promote aggregation and loss of activity. The peptide adsorbs to some plastic and glass surfaces, so a carrier protein is often added to dilute working solutions. Manufacturer instructions and published protocols both govern handling.
Identity and purity testing for thymosin alpha 1 relies mainly on reversed-phase high-performance liquid chromatography and mass spectrometry. Chromatography separates the parent peptide from truncated or modified variants, while mass spectrometry confirms the expected molecular mass. Amino acid analysis and peptide mapping provide additional sequence confirmation. Counterion content, water content, and residual solvents are measured separately as part of specification testing. No single method captures every attribute, so laboratories combine several techniques.
The peptide lacks cysteine, methionine, and tryptophan, so disulfide scrambling and sulfur oxidation are not major degradation routes. Instead, aspartate residues can undergo isomerization or cyclization to succinimide intermediates, generating isoaspartate variants. Hydrolysis of peptide bonds also occurs slowly in solution. These changes may reduce biological activity even when the main peak remains detectable. Stability studies therefore track both potency and the appearance of related substances.
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。
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。
| Property | Value | Notes |
|---|---|---|
| Physical form | Lyophilized powder | Reconstituted before use |
| Typical storage | 2-8 °C, protected from light | Applies to the powder |
| Reconstitution solvent | Sterile water or saline | Follow product labeling |
| Solution stability | Shorter than the powder | Refrigerate and use promptly |
| Primary purity method | Reversed-phase HPLC | Detects related substances |
The compound has been investigated as an adjunct in chronic viral hepatitis and as a vaccine adjuvant, with results that vary by study design and population. Regulators in some countries have approved a synthetic form for specific indications, while other agencies have not. Whether the peptide produces consistent clinical benefit across diverse patient groups is still an open question, and many trials have been small. Its status is therefore best described as investigational in many contexts and established only narrowly.
The name itself causes confusion, because several unrelated thymic peptides share the thymosin label. Thymosin beta-4, for example, is a different molecule with different functions. Naming conventions in the literature also mix descriptive research terms with assigned nonproprietary names, so a reader should confirm which entity a given paper addresses. Clarifying that point is usually the first step in interpreting any claim about this peptide.
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.
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.
== Mechanism of action == Lixisenatide is a member of the class of glucagon-like peptide-1 receptor agonist drugs, each of which activates the GLP-1 receptor. GLP-1 is a hormone that helps pancreatic beta cells to secrete insulin in response to high blood sugar. Because it works like the normal hormone, insulin is only secreted when blood sugar is high. Like GLP-1, it also slows gastric emptying.
Compared to HLF, LSF employs pure cultures at a relatively higher temperature (40–55 °C (104–131 °F)) and lower brine solution concentrations (13–15%). In LSF, koji is mixed with the equivalent weight of brine to form solid moromi. The elevated temperature accelerates the fermentation process significantly. Due to the short aging (15–30 days) period of LSF, and low production cost, LSF soy sauce accounts for more share of the Chinese soy sauce market. LSF evolved from salt-free solid-state fermentation, an even faster method working at even higher temperatures (50–65 °C (122–149 °F)) and taking 72 hours to complete, introduced to China from the Soviet Union in 1958. The aging time turned out to be too short develop a proper flavor profile, with burnt acidic notes left in the sauce. LSF is a compromise between this method and the more traditional HLF: the product tastes passable with more microbes allowed to survive, but still lacks depth. Reducing the salt content accelerates brewing by lifting salt-induced enzyme inhibition.
=== Cuban linkage and "Namibianisation" === During his final years in office, Vorster had recognised that growing international pressure would eventually force South Africa to grant some form of autonomy or independence to South West Africa. He made token acknowledgements of the UN's role in deciding the territory's future and his administration had publicly renounced the notion of annexation. As Vorster's successor, Botha felt bound by this commitment—at least in principle—to an autonomous South West Africa. His strategy was to cultivate a viable political alternative to SWAPO, preferably moderate and anti-communist in nature, which was committed to close military and security links with South Africa. In the meantime, Botha forestalled further discussions on an internal settlement by demanding the withdrawal of the Cuban armed forces from Angola as a precondition of Namibian independence. Botha argued that the Cuban presence in Angola constituted a legitimate security concern for South West Africa, so it was not unreasonable that independence be contingent on a prior Cuban withdrawal. This initiative was supported by the US, which wanted a Namibian settlement consistent with Western interests, namely a region free of what Chester Crocker termed "Soviet-Cuban military adventurism". Crocker endorsed the linkage since it was related to South West Africa's security situation, which needed to be stabilised prior to independence. Botha's precondition was denounced by SWAPO for arbitrarily tying South West Africa's fate to the resolution of another regional conflict.
Sources: en.wikipedia.org
The Russian interior ministry placed Zelenskyy in its list of wanted criminals. Ukraine claimed to have shot down a Russian Su-25 fighter jet over Donetsk Oblast. The Russian defence ministry claimed to have shot four ATACMS missiles over Crimea. A court in Russia sentenced a Ukrainian POW captured during the Siege of Mariupol to 18 years imprisonment for membership in the Azov Battalion.
The most common cause of CH is dysgenesis of the thyroid gland After many years of newborn screening, the incidence of CH worldwide had been estimated at 1:3600 births, with no obvious increases in specific ethnic groups. Recent data from certain regions have shown an increase, with New York reporting an incidence of 1:1700. Reasons for the apparent increase in incidence have been studied, but no explanation has been found. Classic CAH, the disorder targeted by newborn screening programs, is caused by a deficiency of the enzyme steroid 21-hydroxylase and comes in two forms – simple virilizing and a salt-wasting form. The incidence of CAH can vary greatly between populations. The highest reported incidence rates are among the Yupic Eskimos of Alaska (1:280) and on the French island of Réunion (1:2100).
==== Pneumococcal vaccine ==== In 2010, as part of a 10-year pneumococcal vaccine Advance Market Commitment, the companies GlaxoSmithKline (GSK) and Pfizer were both allocated $225 million in AMC subsidies to provide 30 million doses annually at a maximum tail price of $3.50 per dose ($10.50 per child for three doses). In 2011, Médecins Sans Frontières (MSF) recommended that Gavi change the ways in which it procures vaccines. MSF argued that the Advance Market Commitment had transferred more money to GSK and Pfizer than the Gavi grants had transferred to low-cost suppliers for technology transfer and product development. MSF said that large pharmaceutical multinationals had been found to put very high markups on prices, and internationally certified vaccine could be made for about 40% less cost by smaller companies in India and China, despite patent-related obstacles. In January 2015, MSF also called upon GSK and Pfizer to cut the price of the pneumococcal vaccine to US$5 per child in developing countries, a price they estimated as competitive. They said that, as Pfizer had made $16 billion in revenue on pneumococcal vaccine in the last four years, a larger price cut would be affordable. In early 2016, they ran the "A fair shot" campaign to pressure GSK and Pfizer to drop prices. Pfizer said that they were already selling the vaccine at "far below" cost, while GSK said that the price enabled them to "just about" cover their costs, and "To discount it further would threaten our ability to supply it to these countries in the long-term".
==== Exotic forms ==== Water and other volatiles probably comprise much of the internal structures of Uranus and Neptune and the water in the deeper layers may be in the form of ionic water in which the molecules break down into a soup of hydrogen and oxygen ions, and deeper still as superionic water in which the oxygen crystallizes, but the hydrogen ions float about freely within the oxygen lattice.
Sources: en.wikipedia.org
The lyophilized powder is kept refrigerated at 2 to 8 degrees Celsius and protected from light. Reconstituted solutions should be used promptly. Freezing and thawing repeatedly is avoided.
Reversed-phase HPLC is the primary tool for purity, paired with mass spectrometry for identity. Amino acid analysis and peptide mapping add sequence confirmation. Several techniques are combined because no single test covers every attribute.
It lacks sulfur-containing residues, so oxidation is limited. Aspartate isomerization and slow hydrolysis are the main concerns. Solution stability is shorter than that of the lyophilized powder.
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。