If you have been reading about thymalfasin and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Updated 2026-03-15. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Several names appear in the literature for this peptide, including thymalfasin and the abbreviation T-alpha-1. Naming conventions differ among research articles, regulatory documents, and supplier catalogs, which complicates literature searches. Both synthetic and recombinant production routes yield a peptide with the same 28-residue sequence as the thymic isolate. Because the thymosin label also covers unrelated peptides, sources should be compared by sequence rather than by name alone.
The peptide occurs naturally in thymic tissue and has been detected in serum and other biological fluids. Reported concentrations are low, and reliable measurement generally requires immunoassay or mass spectrometry with an enrichment step. It is released from a larger precursor, prothymosin alpha, by proteolytic cleavage, although the enzymes involved are not fully characterized. Whether circulating levels reflect thymic output specifically remains an open question.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Acetylated peptide | N-terminal acetyl group blocks aminopeptidase attack |
| Residue count | 28 amino acids | Matches the N-terminus of prothymosin alpha |
| Molecular mass | About 3,108 Da | Value for the free, unmodified peptide |
| Isoelectric point | Approximately 4.2 | Acidic; net negative charge at neutral pH |
| Encoding gene | PTMA | Human gene for the precursor protein |
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
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。
==== GnRH-associated peptide ==== GnRH-associated peptide (GAP), a 56-amino-acid peptide cleaved from the GnRH precursor, was shown in 1985 to inhibit prolactin secretion in rat pituitary cultures at a potency comparable to dopamine. Its physiological significance in vivo remains uncertain, as results have varied across species.
Eastern Approaches – Fitzroy Maclean's memoir provides his personal experiences in the fledgling SAS in the Western Desert Campaign. Bravo Two Zero – Memoir about a failed SAS mission by Andy McNab. Bravo Two Zero – 1999 miniseries based on the book of the same name by Andy McNab. Red Notice – Novel by Andy McNab, part of his Tom Buckingham Series. SAS: Red Notice – 2021 film based on the book of the same name by Andy McNab. The One That Got Away – Memoir about the Bravo Two Zero mission by Chris Ryan. The One That Got Away – Film based on the book of the same name by Chris Ryan. The Feather Men – Novel by Sir Ranulph Fiennes, claimed by the author to be a partly non-fictional story involving the SAS. Killer Elite – Film based on The Feathermen, about a mercenary hired to kill SAS troopers (fictional story surrounding real events and people from SAS history). 6 Days – Film about the SAS involvement in the Iranian Embassy siege in 1980. Who Dares Wins – 1982 film, released in the United States as The Final Option. SAS: Rogue Heroes – 2016 book. Television shows about the SAS
Type 1: Antigenically Ran2+, GFAP+, FGFR3+, A2B5−, thus resembling the "type 1 astrocyte" of the postnatal day 7 rat optic nerve. These can arise from the tripotential glial restricted precursor cells (GRP), but not from the bipotential O2A/OPC (oligodendrocyte, type 2 astrocyte precursor, also called Oligodendrocyte progenitor cell) cells. Type 2: Antigenically A2B5+, GFAP+, FGFR3−, Ran 2−. These cells can develop in vitro from the either tripotential GRP (probably via O2A stage), from bipotential O2A cells, or in vivo when these progenitor cells are transplanted into lesion sites (but probably not in normal development, at least not in the rat optic nerve). Type 2 astrocytes are the major astrocytic component in postnatal optic nerve cultures that are generated by O2A cells grown in the presence of fetal calf serum but are not thought to exist in vivo. Some researchers think bipotential O2A cells in turn have been derived from the GRP.
The chemical compound thujone, which is present in the spirit in trace amounts, was blamed for its alleged harmful effects. By 1915, absinthe had been banned in the United States and much of Europe, including France, the Netherlands, Belgium, Switzerland, and Austria-Hungary, though it has not been demonstrated to be any more dangerous than ordinary spirits. Recent studies have shown that absinthe's psychoactive properties, apart from those attributable to its alcohol content, have been exaggerated. Absinthe's revival began in the 1990s, following the adoption of modern European Union food and beverage laws that removed long-standing barriers to its production and sale. By the early 21st century, nearly 200 brands of absinthe were being produced in a dozen countries, most notably in France, Switzerland, Austria, Germany, the Netherlands, Spain, and the Czech Republic.
Sources: en.wikipedia.org
==== Primeiro Comando da Capital ==== The Primeiro Comando da Capital (PCC) is one of Latin America's largest drug cartels. The organization primarily deals with drugs/arms trafficking, bank robberies and hijacking of armored trucks, as well as illegal gambling and smuggling (especially alcohol, tobacco, gold and timber). It is the biggest faction in Brazil, while also having a significant presence through the rest of South America, Portugal and the United States (mostly through the Brazilian-American community). In recent years, the organization has been reported to operate in many other countries as well, mostly through its alliances with foreign criminal groups (such as 'Ndrangheta in Italy, Group America in Serbia, Tren de Aragua in Venezuela, the Triads in China and the Jalisco Cartel in Mexico) and paramilitary groups (such as the FARC in Colombia and EPP in Paraguay). In recent years, there has even been reported activities of the group in West Africa (mostly aligned with local groups such as the Nigerian Mafia), Eastern Europe (through the Russian and Albanian mafias) and the Middle East (through the Turkish and Lebanese mafias). The group has also been alleged to have ties to the Yakuza in Japan and Hezbollah in Lebanon. PCC was originally founded on August 31, 1993, by eight prisoners at Taubaté Penitentiary, called "Piranhão" ("Big Piranha"), in the state of São Paulo. The group initially got together during a football game, where they founded a team called "Comando Capital" (Capital Command).
== History == Gramicidin S was discovered by Russian microbiologist Georgyi Frantsevitch Gause and his wife Maria Brazhnikova in 1942. Within the year Gramicidin S was being used in Soviet military hospitals to treat infection and eventually found usage at the front lines of combat by 1946. Gause was awarded the Stalin Prize for Medicine for his discovery in 1946. In 1944, Gramicidin S was sent by the Ministry of Health of the USSR to Great Britain via the International Red Cross in a collaborative effort to establish the exact structure. English chemist Richard Synge proved that the compound was an original antibiotic and a polypeptide using paper chromatography. He would later go on to receive the Nobel Prize for his work in chromatography. The crystal structure was finally established by Dorothy Hodgkin and Gerhard Schmidt; Margaret Thatcher worked for a term in 1947 with Gerhard Schmidt on the antibiotic Gramicidin S, as an undergraduate research project. The importance of Gramicidin S and antibiotic research in general was so great that Gause was not persecuted during the period of Lysenkoism in the USSR, while many of his colleagues were. Indeed, it was his need for developing new strains to mass-produce antibiotics that allowed politically sanctioned collaborations with geneticists like Joseph Rapoport and Alexander Malinovsky, who would both actively participate in the downfall of Lysenkoism.
The mammalian excretory system involves many components. Like amphibians, mammals are ureotelic, and convert ammonia into urea, which is done by the liver as part of the urea cycle. Bilirubin, a waste product derived from blood cells, is passed through bile and urine with the help of enzymes excreted by the liver. The passing of bilirubin via bile through the intestinal tract gives mammalian feces a distinctive brown coloration. Distinctive features of the mammalian kidney include the presence of the renal pelvis and renal pyramids, and of a clearly distinguishable cortex and medulla, which is due to the presence of elongated loops of Henle. Only the mammalian kidney has a bean shape, although there are some exceptions, such as the multilobed reniculate kidneys of pinnipeds, cetaceans and bears. Most adult placentals have no remaining trace of the cloaca. In the embryo, the embryonic cloaca divides into a posterior region that becomes part of the anus, and an anterior region that has different fates depending on the sex of the individual: in females, it develops into the vestibule or urogenital sinus that receives the urethra and vagina, while in males it forms the entirety of the penile urethra. However, the afrosoricids and some shrews retain a cloaca as adults. In marsupials, the genital tract is separate from the anus, but a trace of the original cloaca does remain externally. Monotremes, which translates from Greek into "single hole", have a true cloaca. Urine flows from the ureters into the cloaca in monotremes and into the bladder in placentals.
Although Barker had previously worked with White, he was feuding with her over the treatment of an elephant at the Los Angeles Zoo. White instead did not attend and pre-recorded her comments that she was scheduled to make about another awardee, Mark Goodson. That same year, Barker donated $1 million (equivalent to $1.4 million in 2021) to the University of Virginia Law School to support the study of animal rights. He made similar donations to Harvard Law School, Stanford Law School, Georgetown University Law Center, Duke University School of Law, Northwestern University Pritzker School of Law, and University of California, Los Angeles. In 2010, the Sea Shepherd Conservation Society announced that it had purchased and outfitted a ship to interdict Japanese whaling operations in the Southern Ocean using $5 million (equivalent to $7.4 million in 2025) provided by Barker. The ship was then named the MY Bob Barker, and its existence was first revealed when it helped discover the location of the Japanese whaling fleet. Barker participated in several PETA public service announcements over the years, including one that claimed that vegetarian diets prevent Alzheimer's disease. In 2010, he donated $2.5 million (equivalent to $3.7 million in 2025) toward the purchase of office space for the organization in Los Angeles. The Bob Barker Building opened in 2012.
where Mej is the mass of ejected material. Assuming the intercepted material is distributed uniformly across the surface of the Earth (4πR 2Earth ), the mass surface density (Σej) of the supernova ejecta on Earth is:
Sources: en.wikipedia.org
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.
The precursor, prothymosin alpha, is encoded by the PTMA gene in humans. The 28-residue peptide corresponds to the N-terminal segment released from that larger protein.
It is produced as a fragment of prothymosin alpha and is present in many tissues. Circulating concentrations are low, which makes routine measurement difficult.
It is a 28-amino-acid peptide originally purified from a bovine thymic extract and later produced synthetically. It is studied mainly for its effects on immune cell function.