An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Pezzanite. Lynn M LM; Chow. Lyndah L; Johnson. Valerie V; Griffenhagen. Gregg M GM; Goodrich. Laurie...
Scientists found that treating horse stem cells with a molecule called poly I:C (which mimics viral RNA) makes them produce more of the natural antibiotic peptide LL‑37 and become better at killing drug‑resistant Staph bacteria. This effect was strongest when the cells were grown in low‑serum conditions, and it also helped immune cells eat the bacteria more efficiently.
The study shows that the immune peptide LL‑37, released by neutrophils, pushes T‑cells to become Th17 cells, a type linked to inflammation, and makes those cells harder to kill. This effect happens through several signaling pathways and isn’t seen with other T‑cell types. Mice lacking LL‑37 have weaker Th17 responses during inflammation, suggesting LL‑37 is important for strong Th17 activity.
Traidl. Stephan S; Roesner. Lennart L; Zeitvogel. Jana J; Werfel. Thomas T
Eczema herpeticum is a dangerous skin infection that can happen in people with eczema. The review shows that patients with this infection have lower levels of the natural antimicrobial peptide LL‑37, along with other immune and skin barrier problems. While this points to LL‑37 as a possible factor, the paper doesn’t give any direct ways to boost it or prove that doing so helps.
Mast cells can shoot out web‑like DNA structures called extracellular traps that are laced with antimicrobial proteins like LL‑37 to snag and kill germs. Making these traps usually kills the mast cell and needs reactive oxygen species from NADPH oxidase. The review explains how scientists study these traps and why different microbes trigger different mast‑cell responses.
The paper reviews how the natural antimicrobial peptide LL‑37, part of our innate immune system, can fight COVID‑19 by sticking to the virus, blocking its entry into cells, and calming inflammation, and it suggests that therapies releasing LL‑37 (like certain stem‑cell treatments) might help severe cases, but it doesn’t give concrete dosing or home‑use instructions.
Gontsarik. Mark M; Mansour. Amira Ben AB; Hong. Linda L; Guizar-Sicairos. Manuel M; Salentinig. Stef...
Scientists made tiny lipid particles that change shape when the environment gets more acidic. These particles can trap the antimicrobial peptide LL‑37 well at low pH (around 4‑4.5) but let it go at higher pH (around 6). The switch is caused by the lipid DODAP becoming positively charged as the pH drops, which reshapes the particles and controls peptide release.
Scientists made eight synthetic molecules that act like natural antimicrobial peptides and can stick together in different shapes. Some of these shapes killed drug‑resistant bacteria and reduced infections in lab tests and in mice, while others were less effective. The way the molecules group together matters for how well they work, but the link isn’t perfect.
Vang. Charmie K CK; Dawrs. Stephanie N SN; Oberlag. Nicole M NM; Gilmore. Anah E AE; Hasan. Nabeeh A...
The study shows that different strains of the bacteria Mycobacterium abscessus survive differently inside human cells. One especially aggressive strain from a sputum sample can avoid being killed by the natural antimicrobial peptide LL‑37 and triggers strong inflammation. This means not all M. abscessus are the same, and some can better dodge our innate defenses.
Quemé-Peña. Mayra M; Juhász. Tünde T; Kohut. Gergely G; Ricci. Maria M; Singh. P...
Scientists studied how the natural peptide LL-37 and similar anticancer peptides stick to cell membranes. They found three different ways the peptides can sit on or attach to the membrane, including a newly seen upright position that might be a step before the peptide actually pierces the membrane. Small changes in the peptide’s sequence or charge can switch which mode it uses.
Assane. I M IM; Santos-Filho. N A NA; de Sousa. E L EL; de Arruda Brasil. M C O MCO; Cilli. E M EM;...
Scientists tested synthetic versions of the human peptide LL-37 (and other similar peptides) on fish blood cells and a range of bacteria that cause disease in fish. They found LL-37 isn’t toxic to the fish cells at the doses tested and can kill several fish pathogens, and it works even better when combined with certain antibiotics. This points to a way to treat fish infections with fewer traditional antibiotics, but it doesn’t give direct tips for personal health or longevity hacks.
Meca. Andreea-Daniela AD; Ștefănescu. Simona S; Bogdan. Maria M; Turcu-Știolic...
The study found that people with active TB had low vitamin D levels, which rose after two months of standard TB drugs. Those whose infection cleared showed lower levels of the antimicrobial peptide LL‑37 and markers of cell cleanup (autophagy and apoptosis) compared to those still infected, suggesting vitamin D and these immune pathways are linked to treatment success.
Majewska. Marta M; Zamlynny. Vlad V; Pieta. Izabela S IS; Nowakowski. Robert R; Pieta. Piotr P
The study shows that the human antimicrobial peptide LL‑37 can break apart membranes that look like bacterial cell walls by first coating them and then acting like a detergent, causing the lipids to change shape and the membrane to fall apart.
Gürsoy. Ulvi K UK; Salli. Krista K; Söderling. Eva E; Gürsoy. Mervi M; Hirvonen. Joha...
A lab study using a 3‑D oral tissue model found that two sugars found in human breast milk, especially 3‑fucosyllactose, can boost the natural antimicrobial protein hBD‑2 in gum cells without causing inflammation. The same sugars didn’t change levels of the peptide LL‑37 or inflammatory signals.
Jackson. Alexander A; Werry. Eryn L EL; O'Brien-Brown. James J; Schiavini. Paolo P; Wilkinson. Shane...
Researchers tested three lab-made chemicals that block a brain‑immune receptor called P2X7. They found that two of them work as expected against ATP, but none of them stop the peptide LL‑37 from turning the receptor on. This suggests that current P2X7 blockers might not stop all inflammation pathways linked to LL‑37.
Balhuizen. Melanie D MD; van Dijk. Albert A; Jansen. Jeroen W A JWA; van de Lest. Chris H A CHA; Vel...
The study shows that the antimicrobial peptide LL‑37 doesn’t make bacteria release protective outer‑membrane vesicles (OMVs), but the OMVs that are already present can soak up LL‑37 and make it less effective at killing Gram‑negative bugs like E. coli. This means bacteria can use OMVs as a shield against LL‑37, reducing its antimicrobial power.
Boucher. Emily E; Brown. Luke L; Lahiri. Priyoshi P; Cobo. Eduardo R ER
Mice that lack their own cathelicidin peptide have fewer immune cells called macrophages go to the belly cavity and those cells are worse at eating bacteria. Adding the human version of the peptide (LL‑37) didn’t fix the problem in mouse cells, suggesting the body’s own version is needed for proper function.
Zhang. Yiming Y; Ma. Miaomiao M; Li. Jun J; Wu. Yingye Y; Xue. Lu L; Zhao. Rongrong R; Wang. Lu L; H...
A small piece of a chlamydia protein (pGP3M) can latch onto the human peptide LL‑37 and calm down skin inflammation in mice that have a psoriasis‑like rash. Giving this fragment reduced redness, scaling and immune‑signaling molecules, showing it works about as well as the whole protein. However, the work is still early‑stage, done in mice, and safety in people isn’t known yet.
Schiffmann. Susanne S; Gunne. Sandra S; Henke. Marina M; Ulshöfer. Thomas T; Steinhilber. Diete...
The research found that sodium bituminosulfonate (SBDS), a topical rosacea treatment, cuts down the release of the antimicrobial peptide LL‑37 and several inflammatory signals (calcium, ROS, VEGF, elastase) from human neutrophils, likely by blocking the enzymes 5‑LO and KLK5 that drive this pathway.
Scientists tested whether the natural peptide LL‑37 can act like a tiny carrier to shove a piece of HIV‑1 DNA into human cells. They found it can bundle the DNA into small particles that protect it from being broken down, and the bundles can get into cells without killing them, although the peptide by itself is toxic. The overall gene‑delivery success was modest – about one‑quarter to one‑third of the cells took up the DNA.
Kopfnagel. Verena V; Dreyer. Sylvia S; Zeitvogel. Jana J; Pieper. Dietmar H DH; Buch. Anna A; Sodeik...
The study found that DNA released from our own skin cells can stick to the antimicrobial peptide LL‑37 (and other similar peptides) and block its ability to kill bacteria and viruses. In people with atopic dermatitis, a lot more free DNA is found on the skin, which explains why infections are common even though the skin still makes these peptides.