An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Byfield. Fitzroy J FJ; Kowalski. Marek M; Cruz. Katrina K; Leszczyńska. Katarzyna K; Namiot. A...
The study shows that the natural antimicrobial peptide LL‑37 makes lung cells tougher and less leaky, which helps stop the bacteria Pseudomonas aeruginosa from getting inside. This effect depends on the amount of LL‑37 and involves changes to the cell’s internal skeleton, but other similar peptides didn’t do the same thing.
The study shows that the antimicrobial peptide LL-37, which is released on neutrophil extracellular traps (NETs), can turn on a key inflammation engine (the NLRP3 inflammasome) in immune cells, causing more inflammatory signals (IL-1β and IL-18). This effect is stronger in cells from lupus patients, and the extra IL-18 can make neutrophils release even more NETs, creating a vicious cycle of inflammation that may worsen disease flares.
Chotjumlong. Pareena P; Bolscher. Jan G JG; Nazmi. Kamran K; Reutrakul. Vichai V; Supanchart. Chayar...
LL-37, a natural antimicrobial peptide, can trigger inflammation in gum cells by boosting COX‑2 enzyme levels and the inflammatory molecule PGE2, and it does this through a specific P2X7 receptor and ERK/JNK signaling pathways.
Hou. Man M; Zhang. Nengwei N; Yang. Jingjing J; Meng. Xiangyu X; Yang. Ruan R; Li. Jian J; Sun. Tiey...
In mice with a serious lung infection caused by MRSA, giving the natural peptide LL-37 (or a similar synthetic peptide called IDR-1) reduced lung damage and lowered inflammatory chemicals in the blood and lungs. The peptides seemed to calm down harmful signaling pathways, helping the animals breathe better.
Suphasiriroj. Wiroj W; Mikami. Masato M; Shimomura. Hiromi H; Sato. Soh S
LL-37, a natural antimicrobial peptide, can dampen inflammation caused by gum‑disease bacteria in lab‑grown mouth cells by cutting down the IL‑8 signal, but the effect varies by bacterial type.
Das. M M; Tomar. N N; Sreenivas. V V; Gupta. N N; Goswami. R R
In a study of 131 young women with low vitamin D, taking high‑dose vitamin D (with or without calcium) for six months raised blood vitamin D levels but did NOT increase the gene activity for the antimicrobial peptide LL‑37 (cathelicidin) or shift immune signaling (Th1/Th2) in their blood cells.
Nijnik. Anastasia A; Pistolic. Jelena J; Cho. Patricia P; Filewod. Niall C J NC; Falsafi. Reza R; Ra...
The study shows that the immune‑boosting peptide LL‑37 works by activating a specific cell‑signaling protein called Lyn, part of the Src family kinases. If Lyn or related kinases are blocked, LL‑37 can’t trigger the usual immune‑cell signals, and the same is true for similar synthetic peptides.
Ren. Shun X SX; Cheng. Alfred S L AS; To. Ka F KF; Tong. Joanna H M JH; Li. May S MS; Shen. Jing J;...
The human peptide LL‑37, which normally helps protect the gut lining, is found at low levels in colon cancer. In lab experiments, adding LL‑37 made cancer cells die through a special pathway that doesn’t need the usual “caspase” proteins, and mice that can’t make LL‑37 got more colon tumors. This shows LL‑37 can trigger cell death in colon cancer, but the work is still early and done in cells and mice, not people.
Vandamme. Dieter D; Landuyt. Bart B; Luyten. Walter W; Schoofs. Liliane L
LL-37 is a natural human peptide that fights bacteria, fungi, and viruses, and also helps control the immune system, heal wounds, grow new blood vessels, and may affect cancer cells. This review gathers what scientists currently know about these many roles.
When someone has a sudden heart attack (STEMI), a natural antimicrobial peptide called LL‑37 drops in the blood but returns to normal within a day, while other peptides (HNP1‑3) rise and stay high. The study shows these changes can somewhat tell a heart attack apart from stable heart disease, but they don’t yet tell us how to prevent or treat it.
Dannehl. Claudia C; Gutsmann. Thomas T; Brezesinski. Gerald G
The study shows that two pieces of the human antimicrobial peptide LL-37 behave very differently when they sit at a surface. The longer piece (LL-32) folds into a stable alpha‑helix and sticks strongly to the surface, which matches its stronger ability to kill microbes. The shorter piece (LL-20) stays mostly floppy and doesn’t bind as well, which explains why it’s much less effective.
A lab study found that a synthetic version of the natural peptide LL‑37, called FF/CAP18, can slow down the growth of colon cancer cells in a dish and trigger early signs of cell death, and it works the same way whether the cells have a normal or mutated p53 gene. This suggests the peptide might help make cancer cells more vulnerable to chemotherapy, but the work is only in cell cultures, not in people.
Xiao. Li L; Crabb. Donna M DM; Dai. Yuling Y; Chen. Yuying Y; Waites. Ken B KB; Atkinson. T Prescott...
The study shows that the natural antimicrobial peptide LL‑37 can kill Ureaplasma bacteria in lab tests, but the bacteria can also turn down the body's own production of LL‑37 and other similar peptides, helping them stick around longer.
Chalmers. James D JD; McHugh. Brian J BJ; Docherty. Catherine C; Govan. John R W JR; Hill. Adam T AT
In people with bronchiectasis, low vitamin‑D levels are very common and are linked to worse lung health, more frequent infections (especially Pseudomonas), and faster decline in breathing ability, while the antimicrobial peptide LL‑37 doesn’t seem to explain this link.
Chen. Xue X; Takai. Toshiro T; Xie. Yang Y; Niyonsaba. François F; Okumura. Ko K; Ogawa. Hideok...
The study shows that the human peptide LL-37 can both calm and boost certain skin inflammation signals depending on the situation. At a relatively high dose, it blocks some inflammatory molecules triggered by viral‑like RNA, but it also ramps up others, especially when combined with skin‑related cytokines like IL‑17 and IL‑22. A reversed‑sequence version works similarly, while a scrambled version does not.
Nascimento. Jéssica M JM; Oliveira. Maria D L MD; Franco. Octávio L OL; Migliolo. Ludovico...
The study shows that the fish‑derived peptide Pa‑MAP works like the human antimicrobial peptide LL‑37: it quickly tears apart cell membranes in a way that could kill a wide range of microbes. The researchers used a special electrical test to see this effect in minutes.
da Silva. Bruno Rocha BR; de Freitas. Victor Aragão Abreu VA; Nascimento-Neto. Luiz Gonzaga LG;...
This review shows that natural antimicrobial peptides like LL‑37 are being studied a lot for fighting bad bacteria in the mouth, especially the ones that cause cavities and gum disease. The research is growing, and these peptides seem to kill microbes without the bacteria quickly becoming resistant, but the paper doesn’t give specific ways to use them at home.
Grossmann. R E RE; Zughaier. S M SM; Liu. S S; Lyles. R H RH; Tangpricha. V V
A study gave a single huge dose of vitamin D (250,000 IU) to adults with cystic fibrosis during a lung flare‑up and found it cut two inflammation markers (TNF‑α and possibly IL‑6) after 12 weeks, but it didn’t change the antimicrobial peptide LL‑37 or other cytokines. The results are specific to sick CF patients and don’t directly tell us how to use vitamin D for general health or performance.
Boesch. Austin W AW; Zhao. Yifeng Y; Landman. Alison S AS; Garcia. Marta Rodriguez MR; Fahey. John V...
Scientists created a test that can measure several immune‑boosting peptides, including LL‑37, at the same time in a single sample. The test is reliable, works over a wide range of concentrations, and can be used with real body fluids, saving time and money compared to doing many separate tests.
Hing. Tressia C TC; Ho. Samantha S; Shih. David Q DQ; Ichikawa. Ryan R; Cheng. Michelle M; Chen. Jer...
In mice, giving the natural antimicrobial peptide LL-37 (called mCRAMP in mice) reduced gut damage and inflammation caused by C. difficile toxin A. The peptide lowered tissue damage, cell death, and inflammatory markers, but the body’s own LL-37 wasn’t enough to stop the inflammation.