An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Cheng. Michelle M; Ho. Samantha S; Yoo. Jun Hwan JH; Tran. Deanna Hoang-Yen DH; Bakirtzi. Kyriaki K;...
A study in mice found that the natural peptide LL‑37 can shrink colon tumors by stopping the supportive fibro‑cells and a process called EMT, rather than killing cancer cells directly. The peptide was given either through a virus or as an enema and lowered tumor size without harming normal tissue, but the methods aren’t ready for everyday use.
Su. Wen W; Chen. Yahui Y; Wang. Caihui C; Ding. Xue X; Rwibasira. Gamariel G; Kong. Yi Y
The human peptide LL-37, known for fighting infections, also blocks platelets from clumping together and forming clots in lab tests and animal models. It does this by turning down key signaling proteins (Src and Akt) that tell platelets to stick and activate.
Chung. Myung-Chul MC; Dean. Scott N SN; van Hoek. Monique L ML
Scientists discovered that the human antimicrobial peptide LL‑37 can slip inside bacteria and latch onto a protein called AcpP, which is involved in making fatty acids. This binding changes the bacteria's fat makeup and makes them more vulnerable to LL‑37, especially when another peptide, SMAP‑29, is present. The finding shows LL‑37 works not just by punching holes in bacterial membranes but also by targeting internal machinery.
Tripathi. Shweta S; Wang. Guangshun G; White. Mitchell M; Qi. Li L; Taubenberger. Jeffery J; Hartsho...
The natural human peptide LL-37 can block some flu viruses, but it works poorly against the 2009 pandemic H1N1 strain. A shorter piece of the same peptide called GI-20 still stops that pandemic virus, suggesting that the middle part of LL-37 is key for antiviral action.
Blower. Ryan J RJ; Barksdale. Stephanie M SM; van Hoek. Monique L ML
The study shows that the human antimicrobial peptide LL‑37 can kill a tough, drug‑resistant Gram‑negative bacterium (Burkholderia thailandensis) and can stop or break down the protective biofilm these bacteria make. Other similar immune peptides didn’t work, but LL‑37 (and its mirror‑image version) were effective in lab tests.
Gambade. Audrey A; Zreika. Sami S; Guéguinou. Maxime M; Chourpa. Igor I; Fromont. Gaëlle G...
The study shows that the antimicrobial peptide LL‑37 can make cancer cells move faster by opening calcium and potassium channels in the cell membrane. Both the natural (L) and mirror‑image (D) forms do this, meaning the effect is likely due to changes in the membrane itself, not a specific receptor. Higher levels of LL‑37 and the TRPV2 channel were found together in breast tumors.
Lee. Weon Ju WJ; Chae. Soo Yuhl SY; Ryu. Hyo Sub HS; Jang. Yong Hyun YH; Lee. Seok-Jong SJ; Kim. Do...
The study looked at how different kinds of light (UVA, red 650 nm, and infrared 830 nm) affect skin cells that make oil and antimicrobial proteins like LL‑37. It found that these light exposures didn’t boost inflammation, didn’t change the amount of oil the cells produced, and didn’t raise LL‑37 levels. So, the lights seem safe for the skin but don’t dramatically alter sebum or immune‑related peptides.
Crotty Alexander. Laura E LE; Shin. Stephanie S; Hwang. John H JH
The review explains that smoking triggers a cascade of inflammatory signals in the lungs, leading to higher levels of several proteins, including the antimicrobial peptide LL‑37. While LL‑37 is part of the body’s immune response, its increase is linked to lung inflammation and disease in smokers.
Banaschewski. Brandon J H BJ; Veldhuizen. Edwin J A EJ; Keating. Eleonora E; Haagsman. Henk P HP; Zu...
Researchers tested mixing lung surfactant with several antimicrobial peptides, including LL‑37, to see if the combo could still spread well in the lungs and kill drug‑resistant bacteria. While all mixes spread better than surfactant alone, the peptide CATH‑2 kept the strongest antibacterial effect; LL‑37 didn’t stand out. The study is still in test‑tube (in‑vitro) stage and needs animal testing before any real‑world use.
Sakoulas. George G; Nonejuie. Poochit P; Kullar. Ravina R; Pogliano. Joseph J; Rybak. Michael J MJ;...
The study looked at five meningitis patients treated with the antibiotic ceftaroline. Giving the drug every 8 hours worked, while giving it every 12 hours failed in one case. Ceftaroline also made the bacteria’s surface more negatively charged, which helped the body’s natural antimicrobial peptide LL‑37 kill the bugs more easily.
Tripathi. Shweta S; Wang. Guangshun G; White. Mitchell M; Rynkiewicz. Michael M; Seaton. Barbara B;...
The study shows that a short piece of the natural immune peptide LL-37, called GI-20, can still boost certain white‑blood‑cell actions against flu virus, just like the full‑length peptide. It works through a specific cell‑surface receptor (FPR‑2) and needs calcium inside the cells. A different short piece from the start of LL-37 (LL‑23) does not have these effects.
The study measured antimicrobial proteins, including LL‑37, in breast milk given to very pre‑term babies. Most of these proteins were higher right after birth (day 7) than later (day 21). Only lactoferrin, not LL‑37, was strong enough to noticeably stop bacterial growth when added to formula. Babies who later got infections had drunk less breast milk overall, meaning they got lower total doses of all the antimicrobial proteins.
Wnorowska. Urszula U; Niemirowicz. Katarzyna K; Myint. Melissa M; Diamond. Scott L SL; Wróblews...
The study shows that the natural antimicrobial peptide LL‑37, which is already in our airways, gets blocked by a virus (Pf1) made by a tough Pseudomonas strain that infects cystic fibrosis lungs. However, lab‑made cationic lipids (CSA‑13, CSA‑131, etc.) still kill the bacteria, stop them from forming protective biofilms, and keep working even in thick CF sputum.
Tripathi. Shweta S; Verma. Anamika A; Kim. Eun-Jeong EJ; White. Mitchell R MR; Hartshorn. Kevan L KL
The study shows that the natural peptide LL‑37 can change how white blood cells (neutrophils) react to flu virus. It makes the cells produce more reactive oxygen (a virus‑killing signal) and more web‑like traps (NETs) that catch the virus, while also dialing down a pro‑inflammatory signal (IL‑8). The peptide works through a specific cell‑surface receptor when it’s attached to the virus, but it doesn’t affect how much virus the cells take in.
Kienhöfer. D D; Hahn. J J; Schubert. I I; Reinwald. C C; Ipseiz. N N; Lang. S C SC; Borràs...
The study looked at whether the antimicrobial peptide LL‑37 (or its mouse version CRAMP) plays a harmful role in lupus or rheumatoid arthritis. It found that people with lupus have higher antibodies against LL‑37, but these don’t link to disease severity. Mice lacking CRAMP showed no difference in disease development or severity compared to normal mice. In short, LL‑37 doesn’t seem to drive these autoimmune diseases.
Yoo. Jun Hwan JH; Ho. Samantha S; Tran. Deanna Hoang-Yen DH; Cheng. Michelle M; Bakirtzi. Kyriaki K;...
In mouse models of gut inflammation, giving the natural antimicrobial peptide LL‑37 (or its mouse version) lowered the amount of collagen that builds up during fibrosis. The same anti‑fibrotic effect was seen in human colon fibroblast cells in a dish, where LL‑37 blocked collagen production triggered by growth factors. This suggests LL‑37 can directly stop scar‑forming processes in the gut, at least in animals and cells.
Gela. A A; Kasetty. G G; Jovic. S S; Ekoff. M M; Nilsson. G G; Mörgelin. M M; Kjellström....
The study shows that the immune signaling protein eotaxin‑3 (CCL26), which is usually linked to allergic reactions, can also kill common airway bacteria by breaking their membranes. When mast cell enzymes cut CCL26, the pieces keep some of the antibacterial power or can neutralize bacterial toxins, but they no longer trigger the usual receptor signals.
Ksiazek. Miroslaw M; Karim. Abdulkarim Y AY; Bryzek. Danuta D; Enghild. Jan J JJ; Thøgersen. Id...
Researchers discovered a new enzyme called mirolase from the gum disease bacterium Tannerella forsythia. This enzyme needs calcium to become active and stays partially blocked by a piece of itself until that piece is broken down. Importantly, mirolase can chew up proteins like fibrinogen, hemoglobin, and the human antimicrobial peptide LL‑37, which helps protect us from infections.
Limoli. Dominique H DH; Rockel. Andrea B AB; Host. Kurtis M KM; Jha. Anuvrat A; Kopp. Benjamin T BT;...
Even tiny amounts of the human antimicrobial peptide LL‑37 can slip into bacteria, stick to their DNA and cause mutations that make the bugs tougher and more likely to cause chronic infections, especially in cystic fibrosis lungs.
Wu. Haihui H; Zeng. Meiqi M; Cho. Eric Y P EY; Jiang. Wenqi W; Sha. Ou O
MrgX2 is a receptor found on certain nerve cells and mast cells that can be turned on by the peptide LL-37 (among other molecules). When activated, it can cause pain signals and release of mast cell chemicals, which are part of the body's immune response. The paper mainly reviews what is known about this receptor and suggests areas for future study.