An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Duan. Zilei Z; Fang. Yaqun Y; Sun. Yang Y; Luan. Ning N; Chen. Xue X; Chen. Mengrou M; Han. Yajun Y;...
The study found that the body’s own antimicrobial peptide LL‑37 can bind to bacterial DNA, turning the DNA into a “trojan horse” that slips into the bloodstream and worsens ulcerative colitis by triggering immune inflammation. This complex also makes the gut lining leakier, helping more bacterial DNA get into the blood.
Ilic. Zoran Z; Saxena. Abhinav R AR; Periasamy. Sivakumar S; Crawford. Dana R DR
The study shows that both normal and slightly damaged mitochondrial RNA can spark inflammation in human immune cells, and the natural peptide LL‑37 makes this effect stronger. Even RNA floating in our blood can act as an inflammation trigger. This helps explain how cellular damage might fuel chronic inflammation.
The study shows that the natural immune peptide LL‑37, when produced by certain immune cells, can actually help lung cancer grow by turning on a cell‑growth pathway (Wnt/β‑catenin). Higher levels of LL‑37 were found in lung tumors and linked to worse outcomes, meaning more of this peptide may be harmful rather than helpful.
Roy. Maëva M; Lebeau. Lucie L; Chessa. Céline C; Damour. Alexia A; Ladram. Ali A; Oury. Br...
The frog skin peptides temporin‑SHa and its synthetic version [Kβ]SHa can stop herpes simplex virus‑1 (HSV‑1) from replicating in human skin cells at micromolar doses. They work by directly killing the virus particles, unlike the human peptide LL‑37, which boosts the cell’s own antiviral defenses. Their effect is similar to another frog peptide (temporin‑Tb) but not as strong as LL‑37.
Zhu. Yanyu Y; Mohapatra. Sonisilpa S; Weisshaar. James C JC
The study shows that the human antimicrobial peptide LL‑37 can quickly enter E. coli bacteria, stick to the DNA and ribosomes, and make the cell’s interior stiff and immobile. This stops the bacteria from growing and they never recover, even after washing away excess peptide.
The study shows that using colistin alone won’t clear a tough bone infection caused by a resistant Klebsiella strain, but pairing it with meropenem or fosfomycin works well, while adding tigecycline actually makes things worse. It also found that bacteria that become resistant to colistin can sometimes become resistant to the body’s own antimicrobial peptide LL‑37.
Brauncajs. Małgorzata M; Ksiąszczyk. Krzysztof K; Lewandowska-Polak. Anna A; Gorzela. Ka...
A tiny study looked at whether shining low‑level laser light on pressure sores changes the body’s natural antimicrobial peptide LL‑37 and helps heal the wound, especially when bacteria are present. They saw LL‑37 levels rise after two weeks of laser treatment, but they couldn't clearly show that the sores healed better, and the sample size was very small.
Ulloa. Erlinda R ER; Dillon. Nicholas N; Tsunemoto. Hannah H; Pogliano. Joe J; Sakoulas. George G; N...
The study found that the drug avibactam, which is usually paired with antibiotics, can make a tough, drug‑resistant Klebsiella pneumoniae strain more vulnerable to the body’s natural defenses, especially the antimicrobial peptide LL‑37 and immune cells like neutrophils. In mice, giving avibactam alone lowered the bacteria in the lungs, showing it helps the immune system clear the infection even though it doesn’t directly kill the bacteria on its own.
Wang. Jiani J; Cheng. Michelle M; Law. Ivy K M IKM; Ortiz. Christina C; Sun. Mingjun M; Koon. Hon Wa...
The study shows that the natural peptide LL‑37 can slow down the spread of colon cancer cells in mice by acting through a receptor called P2RX7. When LL‑37 levels are increased, fewer cancer cells reach the lungs and liver, and the cells move less in lab dishes. Blocking the P2RX7 receptor stops this effect, indicating the peptide works through that pathway.
In people with stable COPD, blood levels of the immune peptide LL‑37 are lower while the inflammation driver NF‑κB is higher, especially in the most severe disease stage. The two markers are inversely linked, meaning when LL‑37 drops, NF‑κB rises, and lower LL‑37 is tied to poorer lung function.
Scheid. Annette A; Li. Ning N; Jeffers. Carleen C; Borriello. Francesco F; Joshi. Sweta S; Ozonoff....
The study shows that adding the antimicrobial peptide LL‑37 to newborn cord blood in the lab makes the blood better at killing common bacteria (Staph aureus, Staph epidermidis) and a fungus (Candida albicans). This effect was seen in both full‑term and pre‑term blood, while a similar protein called mannose‑binding lectin only helped a little against the fungus in some cases.
Aidoukovitch. Alexandra A; Anders. Emma E; Dahl. Sara S; Nebel. Daniel D; Svensson. Daniel D; Nilsso...
The human peptide LL‑37 can get inside gum‑related cells and stop them from making a inflammation signal (MCP‑1) when they are exposed to bacterial toxins. It does this without changing the usual NF‑κB pathway and may work by binding directly to DNA inside the cell.
Fülöp. Tamàs T; Itzhaki. Ruth F RF; Balin. Brian J BJ; Miklossy. Judith J; Barron. An...
Researchers at a 2017 symposium proposed that the natural antimicrobial peptide LL‑37 can bind the brain protein amyloid‑beta (Aβ) that builds up in Alzheimer's disease. When LL‑37 attaches to Aβ, it may keep it soluble and prevent the toxic plaques that cause brain damage. The idea is that low levels of LL‑37 in the brain could let infections persist and allow Aβ to accumulate, contributing to Alzheimer's.
Hitchon. Carol A CA; Meng. Xiaobo X; El Gabalawy. Hani S HS; Larcombe. Linda L
In people with early joint inflammation, higher blood levels of the immune peptide LL‑37 were strongly linked to having anti‑CCP antibodies, which are a marker for developing rheumatoid arthritis. Most participants also had low vitamin D, which normally helps control LL‑37 production.
Skottrup. Peter Durand PD; López. Rodrigo R; Ksiazek. Miroslaw M; Højrup. Peter P; Baelum....
Scientists made a new test that can spot a bacterial protein called karilysin in spit. People with gum disease had higher levels of this protein than healthy folks. The test is reliable and could be used to monitor oral health, but it doesn’t give direct tips on using the LL‑37 peptide or changing diet or supplements.
Jiang. Lanlan L; Fang. Meifei M; Tao. Renchuan R; Yong. Xiangzhi X; Wu. Tiantian T
The study shows that adding lab‑made IL‑17A protein to mouth‑lining cells stops Candida fungus from growing and makes the cells produce more natural antimicrobial proteins like LL‑37, though the actual LL‑37 protein wasn’t detected.
Burkes. Robert M RM; Astemborski. Jacquie J; Lambert. Allison A AA; Brown. Todd T TT; Wise. Robert A...
In a group of mostly African‑American smokers, people with low blood levels of the peptide LL‑37 (cathelicidin) tended to have a modest but consistent drop in lung function over 6‑18 months, even though their vitamin D levels didn’t affect LL‑37. The peptide levels stayed steady over time, so a low reading likely reflects a personal baseline rather than short‑term changes.
Dahesh. Samira S; Wong. Brian B; Nizet. Victor V; Sakoulas. George G; Tran. Truc T TT; Aitken. Samue...
Researchers found that using the antibiotic oritavancin together with ampicillin worked well against a tough, drug‑resistant spine infection, and the combo was even stronger when they added rifampin or the natural immune peptide LL‑37. This shows that certain drug pairings can boost each other's ability to kill stubborn bacteria.
Karsiyaka Hendek. Meltem M; Erkmen Almaz. Merve M; Olgun. Ebru E; Kisa. Ucler U
Kids who breathe other people's cigarette smoke have lower levels of the natural mouth defender LL-37 and worse gum health. The study shows passive smoking can weaken the mouth's antimicrobial shield, leading to more plaque and gum inflammation.
Camargo Moreno. M M; Lewis. J B JB; Kovacs. E J EJ; Lowery. E M EM
People who drink a lot of alcohol before donating lungs have higher levels of the natural antimicrobial peptide LL‑37 and the inflammation signal CXCL8 in their lung fluid. This suggests that heavy drinking changes the lung's innate immune response, which could affect how well a transplanted lung works later on.