Everything below concerns Immune modulation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2025-09-20. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Biologically, the peptide is studied mainly in the context of immune cell development and regulation. It is produced in the thymus and in several other tissues, and it appears to influence the maturation and activity of T cells and other immune populations. Laboratory work describes effects on cytokine production, on the balance between T cell subsets, and on the function of dendritic cells. Much of this evidence comes from cell culture and animal models, so the extent to which the same pathways operate in humans remains an open question.
Clinical interest has centered on chronic viral hepatitis, on immune restoration in various conditions, and on use as an adjuvant intended to improve responses to vaccines. Trials have reported mixed results, and regulatory status differs sharply between countries; in some places it is a prescription product, while elsewhere it is sold without an approved therapeutic indication. Because published studies vary widely in design, population, and endpoints, comparisons across them are difficult and no single conclusion covers the whole literature.
Thymosin alpha 1 is a short peptide of 28 amino acid residues that derives from the amino terminal region of a larger precursor protein known as prothymosin alpha. The peptide carries an acetyl group on its first residue and contains no disulfide bonds or carbohydrate chains. Its sequence is highly conserved across mammalian species, which is one reason laboratories treat it as a molecule with a defined and reproducible structure rather than a variable tissue extract. The name follows an early naming convention for thymus-derived fractions and does not imply that the peptide acts as a hormone in the classical endocrine sense.
| 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 |
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.
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.
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.
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.
Alanine (symbol Ala or A), or α-alanine, is an α-amino acid that is used in the biosynthesis of proteins. It contains an amine group and a carboxylic acid group, both attached to the central carbon atom which also carries a methyl group side chain. Consequently it is classified as a non-polar, aliphatic α-amino acid. Under biological conditions, alanine exists in its zwitterionic form with its amine group protonated (as −NH+3) and its carboxyl group deprotonated (as −CO−2). Alanine is encoded by all codons starting with GC (GCU, GCC, GCA, and GCG). The L-isomer of alanine (left-handed) is the one that is incorporated into proteins. L-alanine is second only to L-leucine in rate of occurrence, accounting for 7.8% of the primary structure in a sample of 1,150 proteins. The right-handed form, D-alanine, occurs in peptides in some bacterial cell walls (in peptidoglycan) and in some peptide antibiotics, and occurs in the tissues of many crustaceans and molluscs as an osmolyte. Alanine is not an essential amino acid in humans because it can be synthesized metabolically and does not need to be present in the diet. However hypoalaninemia (alanine deficiency) is possible under certain conditions such as ketotic hypoglycemia.
== Civilian applications == Depleted uranium has a very high density and is primarily used as shielding material for other radioactive material, and as ballast. Examples include sailboat keels, as counterweights and as shielding in industrial radiography cameras.
This excretion of glucose in the urine, which does not seem to disturb other blood electrolytes, is accompanied by some diuresis which may be what contributes to many other physiological functions, potentially explaining its place in heart failure treatment. Empagliflozin was approved for medical use in the United States and in the European Union in 2014. It is on the World Health Organization's List of Essential Medicines. In 2023, it was the 34th most commonly prescribed medication in the United States, with more than 16 million prescriptions. It received approval as a generic medication from the US Food and Drug Administration (FDA) in 2022.
=== Snake venom === Although LAAOs are present in a variety of eukaryotic and prokaryotic organisms, snake venom is a particularly rich source of the enzyme and the LAAOs are proposed to supply toxic effects upon envenomation. LAAOs that have been purified from the venoms of various snake species have proven to be the best suitors for examining this novel family of enzymes. It has been determined in most cases concerning the snake families, such as Viperidae, Crotalidae, and Elapidae, that snake venom-LAAO (sv-LAAO) constitutes about 1%–9% of the total protein quantity.
Sources: en.wikipedia.org
== Further reading == Robinson, David A. (2008), "Field Estimation of Soil Water Content: A Practical Guide to Methods, Instrumentation and Sensor Technology" (PDF), Soil Science Society of America Journal, 73 (4), Vienna, Austria: International Atomic Energy Agency: 131, Bibcode:2009SSASJ..73.1437R, doi:10.2136/sssaj2008.0016br, ISSN 1018-5518, IAEA-TCS-30 Wessel-Bothe, Weihermüller (2020): Field Measurement Methods in Soil Science. New practical guide to soil measurements explains the principles of operation of different moisture sensor types (independent of manufacturer), their accuracy, fields of application and how such sensors are installed, as well as subtleties of the data so obtained. Also deals with other crop-related soil parameters.
=== Screening glucose challenge test === The screening glucose challenge test (sometimes called the O'Sullivan test) is performed between 24 and 28 weeks and can be seen as a simplified version of the oral glucose tolerance test (OGTT). No previous fasting is required for this screening test, in contrast to the OGTT. The O'Sullivan test involves drinking a solution containing 50 grams of glucose and measuring blood levels one hour later. If the cut-off point is set at 140 mg/dL (7.8 mmol/L), 80% of women with GDM will be detected. If this threshold for further testing is lowered to 130 mg/dL, 90% of GDM cases will be detected, but there will also be more women who will be subjected to a consequent OGTT unnecessarily.
== Species distribution == Hemocyanin was first discovered in Octopus vulgaris by Leon Fredericq in 1878. The presence of copper in molluscs was detected even earlier by Bartolomeo Bizio in 1833. Hemocyanins are found in the Mollusca and Arthropoda, including cephalopods and crustaceans, and utilized by some land arthropods such as the tarantula Eurypelma californicum, the emperor scorpion, and the centipede Scutigera coleoptrata. Also, larval storage proteins in many insects appear to be derived from hemocyanins.
== Original restaurant == The first In-N-Out restaurant that opened in 1948 was demolished when Interstate 10 (then US 60/US 70/US 99, the Ramona Freeway, now the San Bernardino Freeway) was built from downtown Los Angeles to the San Gabriel Valley. The freeway runs over the original location. A new restaurant was completed in 1954 near the original Baldwin Park, California, location. It was closed in November 2004 and demolished on April 16, 2011, despite discussions about using it as an In-N-Out museum chronicling the origins and history of the company. In-N-Out built a replacement restaurant on the other side of the freeway next to the original In-N-Out University (opened in 1984). A new In-N-Out University was built on the property. The university building houses the training department, which was moved from Irvine, California. In addition, the company restaurant was moved from In-N-Out's Baldwin Park headquarters to the new lot, which holds the restaurant and university, less than a thousand feet away. In 2014, a replica of the first In-N-Out was built in Baldwin Park.
At birth, the liver comprises roughly 4% of body weight and weighs on average about 120 g (4 oz). Over the course of further development, it will increase to 1.4–1.6 kg (3.1–3.5 lb) but will only take up 2.5–3.5% of body weight. Hepatosomatic index (HSI) is the ratio of liver weight to body weight.
Sources: en.wikipedia.org
mass spectrometry (MS) An analytical technique that measures the mass-to-charge ratio of ions in a chemical sample by bombarding the sample with electrons to the point of ionization and then separating the charged fragments by subjecting them to an electric or magnetic field, typically in order to determine the elemental or isotopic signatures of an unknown substance, the masses of its constituent particles, and/or the identities or structures of the molecules within it. The results are presented as a mass spectrum, a plot of the intensity of ion signals as a function of the mass-to-charge ratio.
In practice, 48 states and the District of Columbia require their electors to vote for the statewide popular-vote winner; Maine and Nebraska award two votes to the statewide winner and one to the winner in each congressional district. Both the president and the vice president serve a four-year term, and the president may be reelected to the office only once, for one additional four-year term.
== Career and research == Dai graduated from King's College London, where he also obtained his PhD. After postdoctoral work at McMaster University, Hamilton, he moved to University of Wales Cardiff, where he progressed to a personal chair. In 1989 he moved to Swansea as Head of the Mass Spectrometry Research Unit at University of Wales, Swansea. Although best known as a mass spectrometrist and separation scientist who was the first person to bring liquid chromatography-mass spectrometry to Europe, he has made considerable contributions in organic chemistry research and served as Head of the Chemistry Department at Swansea.
In living cells, DNP acts as a protonophore, an agent that can shuttle protons (hydrogen cations) across biological membranes. It dissipates the proton gradient across the mitochondrial membrane, collapsing the proton motive force that the cell uses to produce most of its ATP chemical energy. Instead of producing ATP, the energy of the proton gradient is lost as heat. The inefficiency is proportional to the dose of DNP that is taken. As the dose increases and energy production is made more inefficient, metabolic rate increases (and more fat is burned) in order to compensate for the inefficiency and to meet energy demands. DNP is probably the best known agent for uncoupling oxidative phosphorylation. The phosphorylation of adenosine diphosphate (ADP) by ATP synthase gets disconnected or uncoupled from oxidation. DNP raises the basal metabolic rate (BMR) and lowers T4 (thyroid hormone) levels by increasing T4 metabolism and reducing thyroid hormone secretion. Because it binds to thyroxine-binding globulin, overall thyroid function may not be affected. DNP cannot substitute for thyroid hormone in myxedema.
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.
The name reflects an early convention for naming thymus-derived fractions. The peptide is characterized and measured as a defined molecule, and it does not operate through a single classical endocrine axis.