An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Ries. Moritz M; Schuster. Philipp P; Thomann. Sabrina S; Donhauser. Norbert N; Vollmer. Jörg J;...
The study found that tiny pieces of mitochondrial DNA can wake up a special immune cell called plasmacytoid dendritic cells, making them release interferon‑alpha, and that the human peptide LL‑37 helps these DNA pieces get inside the cells even without a lab‑made delivery tool. This shows a natural way the body might sense cell damage, but the work was done in test‑tube experiments, not in people.
Li. D D; Beisswenger. C C; Herr. C C; Schmid. R M RM; Gallo. R L RL; Han. G G; Zakharkina. T T; Bals...
The study shows that the immune‑system peptide LL‑37, when made by certain white‑blood cells, actually helps lung tumors grow faster in mice exposed to cigarette smoke. Mice that can’t make this peptide don’t get the smoke‑driven tumor boost, and the peptide’s production depends on inflammation signals from cancer cells.
The gut lining uses antimicrobial proteins like LL‑37 to keep harmful bacteria away, while friendly microbes can survive these defenses. Some bacteria can even turn down the production of LL‑37, weakening the barrier, but good bacteria like Lactobacilli can boost its levels. This back‑and‑forth helps shape the overall gut microbiome.
Ratajczak. Mariusz Z MZ; Kim. ChiHwa C; Ratajczak. Janina J; Janowska-Wieczorek. Anna A
After a bone‑marrow transplant, the body’s immune system releases a peptide called LL‑37, which helps the incoming stem cells find their way back to the marrow. This works together with other signals like SDF‑1 and certain lipids to improve the “homing” process that’s needed for the transplant to succeed.
Baerveldt. E M EM; Onderdijk. A J AJ; Kurek. D D; Kant. M M; Florencia. E F EF; Ijpma. A S AS; van d...
A single dose of the psoriasis drug ustekinumab lowered some skin genes linked to psoriasis but didn’t change the levels of the antimicrobial peptide LL‑37 or other skin defenses. Patients also showed clinical improvement and some shifts in blood inflammation proteins.
Sperrhacke. Maria M; Fischer. Jan J; Wu. Zhihong Z; Klünder. Sarah S; Sedlacek. Radislav R; Sch...
Scientists found that a skin‑derived peptide called SPINK9 can trigger skin cells to move and heal by turning on the EGFR pathway, and it does this through purinergic receptors, similar to how other cationic peptides like LL‑37 work.
Zou. Xianqiong X; Sorenson. Brent S BS; Ross. Karen F KF; Herzberg. Mark C MC
Scientists showed that putting mRNA that codes for the antimicrobial proteins LL‑37 and calprotectin into mouth‑lining cells makes those cells better at fighting off harmful bacteria for about two days, but it also slightly harms the cells themselves.
Findlay. Brandon B; Mookherjee. Neeloffer N; Schweizer. Frank F
Researchers tested tiny, positively‑charged lipopeptides and peptoid molecules and found some of them can make immune cells release the helpful signal IL‑8 without triggering the more dangerous inflammatory cytokine TNF‑α. A few of these new compounds even outperformed the natural peptide LL‑37 in lab tests, and they’re built to resist breakdown in the body, which could make them more effective if turned into a drug.
Napier. Brooke A BA; Burd. Eileen M EM; Satola. Sarah W SW; Cagle. Stephanie M SM; Ray. Susan M SM;...
The study shows that using the antibiotic colistin to treat tough infections can make the bacteria not only resistant to colistin but also to natural immune proteins like LL‑37 and lysozyme. This means the bacteria become harder for our own bodies to fight after colistin treatment.
Scientists discovered a new antimicrobial peptide called CATH_BRALE from an ancient fish. It’s highly positively charged, has a unique repeat sequence, and kills gram‑negative bacteria better than the human peptide LL‑37 in lab tests. However, it’s only been studied in fish and in test‑tube experiments, so there’s no human safety or dosage info yet.
Jeong. Mi Sook MS; Kim. Ji-Yun JY; Lee. He In HI; Seo. Seong Jun SJ
The researchers showed that calcitriol, the active form of vitamin D3, can dial down the skin cells' production of the antimicrobial peptide LL‑37 and several inflammation‑related signals when those cells are stimulated by bacterial components or UV light. In plain terms, vitamin D may calm skin inflammation but might also lower a natural skin defense molecule.
LL-37 sticks to actin proteins. At high amounts it makes actin fibers join together, which can thicken mucus like in cystic fibrosis. At low amounts it actually blocks actin from forming fibers and speeds up its breakdown. The bundles it creates can be broken apart by DNase‑1 or cofilin.
Emelianov. V U VU; Bechara. F G FG; Gläser. R R; Langan. E A EA; Taungjaruwinai. W M WM; Schr&#...
The study found that people with hidradenitis suppurativa (a painful skin condition) have much higher levels of the antimicrobial peptide LL‑37 in their sweat glands and hair follicles, which may help trigger the inflammation that drives the disease.
LL-37 is a natural skin peptide that’s found in higher amounts in psoriasis. It can grab DNA released from dying cells, which sometimes sparks an immune flare‑up, but it can also calm down DNA‑driven inflammation inside skin cells. Treatments like vitamin D creams or UV light raise LL-37 levels yet still help psoriasis, showing the peptide’s role is complicated.
Fox. Marc A MA; Thwaite. Joanne E JE; Ulaeto. David O DO; Atkins. Timothy P TP; Atkins. Helen S HS
Scientists mixed parts of three natural antimicrobial proteins to make new hybrid peptides that kill bacteria better than the originals, but they also damage red blood cells more. Tweaking the most harmful hybrid reduced both its killing power and its blood‑cell toxicity, showing a trade‑off between effectiveness and safety.
Hoffmann. Markus H MH; Bruns. Heiko H; Bäckdahl. Liselotte L; Neregård. Petra P; Niederrei...
The study shows that the antimicrobial peptide LL‑37 (and its rat version rCRAMP) is found at much higher levels in joint tissue and blood of people and rats with arthritis, especially in immune cells that cause inflammation. This rise lines up with more cell death, interferon‑alpha, and auto‑antibodies, suggesting LL‑37 may help drive the disease rather than protect against it.
Nan. Yong Hai YH; Bang. Jeong-Kyu JK; Jacob. Binu B; Park. Il-Seon IS; Shin. Song Yub SY
Scientists tweaked a short piece of the human immune peptide LL-37 and found a version (a4‑W2) that kills bacteria well while also neutralizing harmful bacterial toxins, without losing its safety profile. The key was adjusting how water‑loving and fat‑loving parts of the peptide are balanced and swapping a phenylalanine for a tryptophan at a specific spot. This work points to a promising new drug candidate for infections and septic shock, but it’s still early‑stage research.
Kanda. N N; Hau. C S CS; Tada. Y Y; Sato. S S; Watanabe. S S
People with eczema have lower blood levels of the antimicrobial peptide LL‑37 and vitamin D. Giving the active form of vitamin D to skin cells boosts LL‑37 production, and both vitamin D and LL‑37 can increase certain immune signals (IL‑31 and oncostatin M) in T‑cells. For healthy folks, keeping vitamin D sufficient may help maintain LL‑37 levels, but the immune effects are complex and not all clearly beneficial.
Nijnik. Anastasia A; Pistolic. Jelena J; Filewod. Niall C J NC; Hancock. Robert E W RE
LL-37 is a natural skin peptide that helps the immune system. The study shows it works through a chain of signals (P2X7 → Src kinases → Akt → CREB/ATF1) to boost chemicals that attract immune cells, especially when a bacterial protein called flagellin is present. This explains how LL-37 can strengthen skin defenses, but the work is still basic science and doesn’t give direct dosing or product advice.
Supanchart. C C; Thawanaphong. S S; Makeudom. A A; Bolscher. J G JG; Nazmi. K K; Kornak. U U; Krisan...
The study shows that the natural peptide LL‑37 can stop bone‑breaking cells from forming in a lab dish, suggesting it might help protect bone and gum health, but the work is only in vitro and doesn’t give a human dosing plan.