immunomodulatory peptide comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-05-24. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
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.
| Property | Value | Notes |
|---|---|---|
| Class | Synthetic peptide | 28 residues; not a small-molecule compound |
| Molecular mass | About 3,106 Da | Monoisotopic mass of the unmodified chain |
| N-terminal group | Acetylated serine | Present in both native and synthetic forms |
| Secondary structure | Disulfide-constrained loop | One bridge between two cysteine residues |
| Typical source | Solid-phase synthesis | Early isolates came from bovine thymus extracts |
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.
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。
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.
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.
Newsom's first political experience came when he volunteered for Willie Brown's successful campaign for mayor in 1995. Newsom hosted a private fundraiser at his PlumpJack Café. Brown appointed Newsom to a vacant seat on the Parking and Traffic Commission in 1996, and he was later elected president of the commission. Brown appointed him to the San Francisco Board of Supervisors seat vacated by Kevin Shelley in 1997. At the time, he was the youngest member of San Francisco's board of supervisors. Newsom was sworn in by his father and pledged to bring his business experience to the board. Brown called Newsom "part of the future generation of leaders of this great city". Newsom described himself as a "social liberal and a fiscal watchdog". He was elected to a full four-year term to the board in 1998. San Francisco voters chose to abandon at-large elections to the board for the previous district system in 1999. Newsom was reelected in 2000 and 2002 to represent the second district, which includes Pacific Heights, the Marina, Cow Hollow, Sea Cliff, and Laurel Heights, which had San Francisco's highest income level and highest Republican registration. Newsom paid $500 to the San Francisco Republican Party to appear on the party's endorsement slate in 2000 while running for Supervisor. He was reelected. As a San Francisco Supervisor, Newsom gained public attention for his role in advocating reform of the city's municipal railway (Muni). He was one of two supervisors endorsed by Rescue Muni, a transit riders group, in his 1998 reelection.
== External links == "P2Y Receptors: P2Y13". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. Archived from the original on 2016-03-03. Retrieved 2008-12-09. This article incorporates text from the United States National Library of Medicine, which is in the public domain.
Due to disagreements between Banting and MacLeod, there was ill will generated within the team. The Nobel Prize for Medicine was awarded to Banting and MacLeod in 1923. Feeling that Best had been overlooked in the award, Banting shared his portion with Best. In response, MacLeod shared his portion with Collip. Nonetheless, Collip is often overlooked as a co-discoverer of insulin, in part due to Best's public relations campaign that downplayed Collip's crucial role. Following this early success, Collip returned to Edmonton to take up a position as Head of the new Department of Biochemistry, and to pursue his own studies on hormone research. In 1928 he was recruited to McGill University in Montreal by his former graduate advisor, Archibald Macallum. Collip served as Chair of McGill's Department of Biochemistry from 1928 to 1941. From 1947 to 1961, Collip was appointed Dean of Medicine at the University of Western Ontario. He is regarded as a pioneer of endocrine research. He did pioneering work with the parathyroid hormone (PTH). He died on June 19, 1965, at the age of 72.
Sources: en.wikipedia.org
Mass transfer Fontalvo Alzate, Javier (2006). Design and performance of two-phase flow pervaporation and hybrid distillation process. Technische Universiteit Eindhoven, The Netherlands: JWL boekproducties. ISBN 978-90-386-3007-6. Matuschewski, Heike (2008). MSE — modified membranes in organophilic pervaporation for aromatics/aliphatics separation. www.desline.com: Desalination. Eslami, Shahabedin; Aroujalian, Abdolreza; Bonakdarpour, Babak; Raeesi, Ahamdreza (2008). "Coupling of Pervaporation system with Fermentation Process" (PDF). International Congress on Membrane and Membrane Technology (ICOM2008) Honolulu, Hawaii, USA.
=== Abuse and special populations === Benzodiazepine abuse and misuse are guarded against when prescribed to those with alcohol or other drug dependencies or who have psychiatric disorders. Pediatric patients For those less than 18 years of age, this treatment is usually not indicated, except for treatment of epilepsy, and pre-or postoperative treatment. The smallest possible effective dose is typically used for this group of patients. Under 6 months of age, safety and effectiveness have not been established; diazepam is not given to those in this age group. Elderly and seriously ill patients can experience apnea or cardiac arrest. Concomitant use of other central nervous system depressants increases this risk. The smallest possible effective dose is generally used for this group of people. The elderly metabolize benzodiazepines much more slowly than younger adults, and are also more sensitive to the effects of benzodiazepines, even at similar blood plasma levels. Doses of diazepam are recommended to be about half of those given to younger people, and treatment is limited to a maximum of two weeks. Long-acting benzodiazepines such as diazepam are not recommended for the elderly. Diazepam can also be dangerous in geriatric patients owing to a significantly increased risk of falls. Intravenous or intramuscular injections in hypotensive people or those in shock are administered carefully, and vital signs are closely monitored.
=== Economics === When Prilosec's US patent expired in April 2001, AstraZeneca introduced esomeprazole (Nexium) as a patented replacement drug. Many companies introduced generics as AstraZeneca's patents expired worldwide, which are available under many brand names. Omeprazole was a subject of a patent litigation in the U.S. The invention involved application of two different coatings to a drug in pill form to ensure that the omeprazole did not disintegrate before reaching its intended site of action in the stomach. Although the solution by means of two coatings was obvious, the patent was found valid, because the source of the problem was non-obvious and was discovered by the patentee. In September 2023, AstraZeneca announced it would pay $425 million to settle product liability litigations against Prilosec in the United States.
Sources: en.wikipedia.org
Saccharomyces boulardii is a yeast first isolated in 1923 from lychee (Litchi chinensis) and mangosteen (Garcinia mangostana) fruit peels by the French scientist Henri Boulard. Early reports described S. boulardii as a distinct species with unique taxonomic, metabolic, and genetic characteristics; however, subsequent genomic analyses have shown that it is not a separate species but a lineage of Saccharomyces cerevisiae, sharing greater than 99% genomic sequence identity with other S. cerevisiae strains. As a result, it is often referred to as S. cerevisiae var. boulardii. S. boulardii is used as a probiotic yeast, intended to transiently colonize the gastrointestinal tract and reduce the risk of certain gastrointestinal disorders. It is able to grow at human body temperature (37°C; 98.6°F). In healthy individuals, S. boulardii is generally regarded as nonpathogenic and nonsystemic, remaining confined to the gastrointestinal tract. Henri Boulard reportedly became interested in the yeast after observing residents of Southeast Asia consuming lychee and mangosteen skins during cholera outbreaks, a practice believed to alleviate diarrheal symptoms. S. boulardii has also been used as a model organism in molecular biology, and the CRISPR–Cas9 genome-editing system has been demonstrated to function effectively in this yeast.
== Clinical significance == This ligament is an important anatomical landmark of the duodenojejunal flexure, separating the upper and lower gastrointestinal tracts. For example, bloody vomit or melena, black tarry stools, usually indicate a gastrointestinal bleed from a location in the upper gastrointestinal tract. In contrast, hematochezia, bright red blood or clots in the stool, usually indicates gastrointestinal bleeding from the lower part of the gastrointestinal tract. It is an especially important landmark to note when looking at the bowel for the presence of malrotation of the gut, a syndrome often suspected in young children when they have episodes of recurrent vomiting. Visualising a normal location of the ligament of Treitz in radiological images is critical in ruling out malrotation of the gut in a child; it is abnormally located when malrotation is present. During a Whipple's procedure, commonly used to treat pancreatic cancer by removing the pancreas, duodenum, and part of the jejunum, the ligament of Treitz is separated from the duodenum and preserved. When the remaining jejunum is anastamosed with the pylorus of the stomach, it may be passed through the ligament. Superior mesenteric artery syndrome (SMA) is an extremely rare life-threatening condition that can either be congenital and chronic, or induced and acute. SMA Syndrome is characterised by compression of the duodenum between the abdominal aorta and the superior mesenteric artery, and may—when congenital—result from a short suspensory muscle.
Thus, all along the gland, there is only a small gradient to climb, in order to push the salt from the blood to the salty fluid with active transport powered by ATP. b. The blood supply system to the gland is set in countercurrent exchange loop mechanism for keeping the high concentration of salt in the gland's blood, so that it does not leave back to the blood system. The glands remove the salt efficiently and thus allow the birds to drink the salty water from their environment while they are hundreds of miles away from land.
Sources: en.wikipedia.org
Its sequence corresponds to the amino-terminal portion of prothymosin alpha, a larger protein present in many cell types. The isolated 28-residue peptide is a fragment of that protein rather than a separately encoded molecule, and laboratory material is produced by synthesis.
The single bridge between two cysteine residues holds the chain in a folded loop that influences its shape and its behavior in solution. Loss of the bridge through reduction or oxidation shifts chromatographic retention and is tracked during stability work.
It is a defined 28-residue sequence derived from a larger precursor, whereas many other thymic preparations are mixtures of several polypeptides. Its acetylated amino terminus and single disulfide bridge distinguish it chemically from unrelated thymic extracts.
Thymosin fraction 5 is a mixture of many peptides obtained from thymus tissue, while thymosin alpha 1 is a single defined 28-residue molecule. The two names appear together in older literature because the purified peptide was first obtained from that mixture.