An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Boink. Mireille A MA; Roffel. Sanne S; Nazmi. Kamran K; Bolscher. Jan G M JGM; Veerman. Enno C I ECI...
The study shows that the natural peptide LL‑37 (and another saliva peptide, Histatin‑1) can make skin and gum cells release more of an antimicrobial signal called CCL20, even without the usual inflammation trigger IL‑1α. This suggests LL‑37 helps boost the body’s first‑line defense on surfaces like skin and mouth.
Sakoulas. George G; Kumaraswamy. Monika M; Kousha. Armin A; Nizet. Victor V
The study shows that some antibiotics (ceftriaxone, ciprofloxacin, azithromycin) work better against Salmonella when they’re combined with the body’s own antimicrobial peptide LL‑37, and that low‑dose ceftriaxone makes the bacteria easier for blood and immune cells to kill. This suggests that the usual lab tests for antibiotics may miss how well they actually work inside the body.
Scientists found that attaching the antimicrobial peptide LL‑37 (and indolicidin) to tiny carbon nanotubes lets the peptide work at doses 1,000 times lower than when used alone, still boosting immune signaling and protecting immune cells from bacterial infection in lab tests.
Zhang. Ping P; Wright. John A JA; Tymon. Anna A; Nair. Sean P SP
The study shows that the human antimicrobial peptide LL‑37, which some people think could help fight tough Staph infections, loses its power when normal levels of bicarbonate (found in blood and tissues) are present. In those conditions, certain slow‑growing Staph variants become highly resistant, meaning LL‑37 probably won’t work well against them in the body.
Bruce. Kevin E KE; Rued. Britta E BE; Tsui. Ho-Ching Tiffany HT; Winkler. Malcolm E ME
Scientists studied how the bacteria that cause pneumonia react to the human antimicrobial peptide LL‑37 and a chemokine called CXCL10. They found that the bacteria are killed easily in a simple lab solution, but become more resistant in a richer medium. A specific bacterial transporter called Opp makes the bacteria more vulnerable to CXCL10, while changes in another protein (FtsX) don’t affect resistance.
Researchers made a new hybrid peptide that combines parts of two natural antimicrobial proteins (cecropin A and LL‑37). This hybrid kills bacteria better than either piece alone and hurts red blood cells less. They figured out a way to produce it in large amounts using common lab bacteria and showed it stays active under a wide range of temperatures, pH levels, and even after exposure to some digestive enzymes.
The study shows that the antimicrobial peptide LL-37 makes human mast cells release their stored chemicals and produce new inflammatory signals mainly by binding to a receptor called MrgX2. Turning off MrgX2 stops this reaction, while other receptors play only a minor role.
A mouse study found that a specific probiotic strain, Lactobacillus paracasei CNCM I-3689, helped clear vancomycin‑resistant Enterococcus (VRE) from the gut after antibiotics and also boosted the gut’s natural antimicrobial peptide LL‑37. The probiotic seemed to speed up the return of beneficial Bacteroidetes bacteria, which may be part of why VRE numbers dropped.
The study looks at how two human antimicrobial peptides, LL-37 and dermcidin, interact with cell membranes. It shows that dermcidin first forms a six‑unit (hexamer) structure before attaching to membranes, while LL-37 groups together on membranes and can create pore‑like openings, but both behave a bit differently from classic textbook models.
Munguia. Jason J; LaRock. Doris L DL; Tsunemoto. Hannah H; Olson. Joshua J; Cornax. Ingrid I; Poglia...
The study shows that a bacterial system called the Mla pathway helps Pseudomonas aeruginosa resist the natural antimicrobial peptide LL‑37. When the vacJ gene in this pathway is knocked out, the bacteria become leaky, die more easily from LL‑37, blood, and serum, and cause less severe lung infections in mice. This suggests that blocking the Mla pathway could make the body’s own LL‑37 more effective against this bug.
Thomas. Andrew J AJ; Pulsipher. Abigail A; Davis. Brock M BM; Alt. Jeremiah A JA
The immune peptide LL-37 can kill human nasal cells and trigger inflammation, but a lab-made sugar molecule called GM-0111 can stop this damage. The cell death happens through inflammatory pathways, not the usual apoptosis route.
Kim. Eun Young EY; Rajasekaran. Ganesan G; Shin. Song Yub SY
Scientists tweaked a short piece of the human protein LL-37 (called KR-12-a5) by swapping some building blocks for their mirror‑image versions. These changes made the peptide kill resistant bacteria better, work well together with common antibiotics, break down bacterial films, and still calm down inflammation, all while being less harmful to human cells.
Alagarasu. K K; Patil. P S PS; Shil. P P; Seervi. M M; Kakade. M B MB; Tillu. H H; Salunke. A A
In lab tests, the natural peptide LL‑37 can stop dengue virus from infecting cells, but only when the virus is mixed with a fairly high amount of the peptide before it meets the cells. It doesn’t work if you add it to cells first or after the infection has started, and a scrambled version of the peptide does nothing.
Li. Xi X; Yuan. Chao C; Xing. Licong L; Humbert. Philippe P
Researchers looked at the skin bacteria of 100 Chinese women in winter and measured how they relate to skin traits and the antimicrobial peptide LL‑37. They found that different body sites have distinct bacterial mixes, that exposed skin has more diverse microbes, and that LL‑37 levels go hand‑in‑hand with these patterns.
Fujita. Kohei K; Ito. Yutaka Y; Oguma. Tsuyoshi T; Mio. Tadashi T; Niimi. Akio A; Hirai. Toyohiro T
People with Mycobacterium avium complex (MAC) lung disease have lower blood levels of the antimicrobial peptide LL‑37 and weaker bones, and these changes happen even if their vitamin D levels look normal.
Khurshid. Zohaib Z; Naseem. Mustafa M; Yahya I Asiri. Faris F; Mali. Maria M; Sannam Khan. Rabia R;...
LL-37 is a natural antimicrobial peptide found in saliva that helps fight oral germs, supports wound healing, and may influence cancer processes. It works by interacting with the mouth's environment and can trigger inflammation when needed. Researchers are looking at LL-37 for future non‑invasive diagnostic tools using saliva.
The study measured a natural protein called LL‑37 in gum fluid and found that its level goes up when gums are inflamed (gingivitis), but the amount doesn’t change between young and middle‑aged people. Age itself doesn’t affect LL‑37 levels.
Smith. Margaretha E ME; Stockfelt. Marit M; Tengvall. Sara S; Bergman. Peter P; Lindén. Anders...
In healthy people, breathing in a small amount of bacterial toxin (endotoxin) makes the airway release more of the antimicrobial peptide LL‑37, but it doesn't change levels of another peptide, calprotectin. This shows LL‑37 can be quickly turned on by the body's innate immune response in the lungs.
The study shows that the human immune peptide LL‑37 changes shape when it meets cell membranes, forming paired helices that can stick together into fibril‑like structures. These structures can pull out bacterial lipids and break down bacterial membranes, which is how LL‑37 kills microbes. The findings are mostly about how the peptide works at a molecular level, not about how to use it in a supplement or therapy yet.
The antimicrobial peptide LL-37, which some people think about using for its immune‑boosting effects, was found to make skin squamous cell cancer cells grow and spread faster by turning on a protein called YB‑1 through the NF‑κB pathway.