An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
De Lorenzi. Ersilia E; Chiari. Marcella M; Colombo. Raffaella R; Cretich. Marina M; Sola. Laura L; V...
Scientists found that the natural immune peptide LL-37 can stick to the Alzheimer‑related protein Aβ42 and stop it from forming the sticky fibrils that damage brain cells. In lab dishes, LL-37 reduced the toxic effects of Aβ42 on nerve cells, suggesting the two peptides may naturally balance each other in the brain.
The paper reviews human antimicrobial peptides like LL‑37, showing they can kill bacteria, viruses and fungi and also help the immune system without quickly causing resistance. It highlights ongoing work to turn these natural molecules into medicines, but it doesn’t give specific dosing or home‑use instructions.
Zhou. B B; Tu. H L HL; Ba. T T; Wang. L F LF; Wang. S J SJ; Nie. S Y SY
The study shows that human umbilical cord stem cells release the antimicrobial peptide LL‑37, and when their culture fluid is mixed with the antibiotic ciprofloxacin, it makes the drug kill Staph aureus much more effectively in a petri‑dish. Blocking LL‑37 removes most of this boost, so the peptide is the key player. While the work is only in vitro, it hints that adding LL‑37 (or things that raise its levels) could let you use lower antibiotic doses.
Christiansen. Stig Hill SH; Murphy. Ronan A RA; Juul-Madsen. Kristian K; Fredborg. Marlene M; Hvam....
Researchers found that Glatiramer acetate (GA), a drug already used for multiple sclerosis, can quickly kill Gram‑negative bacteria like Pseudomonas aeruginosa, even outperforming the natural antimicrobial peptide LL‑37 in human plasma. The killing happens within minutes and works on lab strains and many clinical isolates, but it doesn’t affect Gram‑positive Staphylococcus aureus as well.
Jiao. Delong D; Wong. Chun-Kwok CK; Tsang. Miranda Sin-Man MS; Chu. Ida Miu-Ting IM; Liu. Dehua D; Z...
The study shows that the antimicrobial peptide LL‑37 can make asthma worse by turning on eosinophils (a type of immune cell) and lung lining cells, leading to more inflammation and airway tightening. In mice, giving the LL‑37 equivalent together with an allergen made breathing problems worse, suggesting LL‑37 may be a trigger for asthma attacks.
Caiaffa. Karina Sampaio KS; Massunari. Loiane L; Danelon. Marcelle M; Abuna. Gabriel Flores GF; Bedr...
Researchers tested a small piece of the natural immune peptide LL‑37 called KR‑12‑a5 and found it kills common mouth bacteria and fungi without harming human cells in lab dishes. It worked better than other tested peptides and reduced bacterial films inside tooth‑like structures, suggesting it could be a safe, strong oral antimicrobial.
Oliveira-Bravo. Martha M; Sangiorgi. Bruno Braga BB; Schiavinato. Josiane Lilian Dos Santos JL; Carv...
LL-37, a natural antimicrobial peptide, makes placenta‑derived stem cells move better and suppress immune cells more strongly in lab tests, without hurting the stem cells.
Krejner. Alicja A; Litwiniuk. Małgorzata M; Grzela. Tomasz T
In a tiny study of 19 people with leg ulcers, the researchers found that higher levels of the natural peptide LL‑37 in the blood were tied to faster wound healing, while low vitamin D levels didn’t matter. This suggests LL‑37 could be a useful marker or treatment target for stubborn wounds, but the evidence is still early and limited to a specific ulcer type.
Treating fat‑derived stem cells with the antimicrobial peptide LL‑37 makes them release factors that help skin fibroblasts move faster, which is important for wound healing. The boost comes from more SDF‑1α being produced, which signals fibroblasts to migrate.
Sousa. Filipa Henderson FH; Casanova. Victor V; Findlay. Fern F; Stevens. Craig C; Svoboda. Pavel P;...
The human antimicrobial peptide LL‑37 (and similar cathelicidins from pigs and sheep) can directly knock down the common cold virus (rhinovirus) when added to the virus or to infected lung cells. It doesn’t kill the cells, but it slows down the virus’s ability to replicate. This suggests that giving extra LL‑37 or a lab‑made version could become a new way to treat colds, especially for people with weak immune systems.
Chen. Chen C; Mangoni. Maria Luisa ML; Di. Y Peter YP
A frog‑skin peptide called Esc(1-21)-1c was tested in mice with a lung infection caused by the tough bacterium Pseudomonas aeruginosa. A single tiny dose (0.1 mg per kg body weight) given directly into the airway, even two hours after the infection started, cut the bacteria in the lungs by about 100‑fold, lowered inflammation, and kept the lung lining intact better than the human peptide LL‑37. The results are still in animal studies, but they point to a potentially powerful, low‑dose inhaled treatment for stubborn lung infections.
Scientists tested two new antimicrobial peptides modeled after the human protein LL‑37 and found they can stop Pseudomonas bacteria from sticking together and forming protective biofilms. The peptides work best when used early, but when a biofilm is already established, combining the peptides with regular antibiotics breaks it down much more completely than either alone.
The study shows that the rosacea cream ivermectin not only kills parasites but also blocks a skin protein called LL‑37 and the enzyme KLK5 that creates it, cutting down inflammation in skin cells. This explains why the cream works for rosacea and suggests it can be used to manage the condition by targeting the immune pathway rather than just symptoms.
White. Mitchell R MR; Tripathi. Shweta S; Verma. Anamika A; Kingma. Paul P; Takahashi. Kazue K; Jens...
LL-37, a natural antimicrobial peptide, can lower the amount of seasonal flu virus that grows inside immune cells and also dampens the inflammation those cells produce, but it works less well against the 2009 pandemic H1N1 strain and the study doesn’t give dosing details.
Han. Jenny E JE; Alvarez. Jessica A JA; Jones. Jennifer L JL; Tangpricha. Vin V; Brown. Mona A MA; H...
Giving a big dose of vitamin D3 (250,000‑500,000 IU over five days) raises the amount of free vitamin D in the blood, and this rise is linked to higher activity of the gene that makes the antimicrobial peptide LL‑37. However, the actual blood levels of LL‑37 and another peptide, hBD‑2, didn't go up, though higher LL‑37 was associated with better immune cell (macrophage) function in the lungs. The study was done in very sick, ventilated patients, so the findings may not directly apply to healthy people, but they hint that high‑dose vitamin D could influence the body’s innate immunity.
A study found that certain plant compounds called triterpenoids—especially ursolic acid and tumulosic acid—can block a skin enzyme (KLK5) that normally activates the antimicrobial peptide LL‑37. By inhibiting this enzyme, these compounds reduced the amount of LL‑37 produced in skin cells without harming the cells, suggesting they could help keep the skin barrier healthier.
Guo. Yi-Jie YJ; Zhang. Bo B; Feng. Xue-Song XS; Ren. Hui-Xun HX; Xu. Ji-Ru JR
The study found that the natural compound EGCG from green tea can kill mouth bacteria and stop them from forming sticky biofilms, and that a human peptide called LL‑37 makes EGCG work even better against these biofilms. While EGCG is easy to get, LL‑37 isn’t a common supplement, so the combo isn’t ready for DIY use yet, but it points to possible future oral‑care products that mix the two.
Lishko. Valeryi K VK; Moreno. Benjamin B; Podolnikova. Nataly P NP; Ugarova. Tatiana P TP
The study shows that the natural antimicrobial peptide LL‑37 can stick to a receptor called Mac‑1 on immune cells, helping those cells grab and eat bacteria more efficiently. When bacteria are coated with LL‑37, macrophages eat them faster, but this only works if the Mac‑1 receptor and certain surface sugars are present.
The study found that bacteria with the MCR-1 gene, which makes them resistant to the antibiotic colistin, are still vulnerable to the human antimicrobial peptide LL-37 and other similar peptides. In other words, resistance to colistin doesn’t automatically mean resistance to these natural immune peptides.
Two. Aimee M AM; Nakatsuji. Teruaki T; Kotol. Paul F PF; Arvanitidou. Evangelia E; Du-Thumm. Laurenc...
Washing your skin with regular soaps temporarily lowers the natural antimicrobial peptide LL‑37 a bit, but it doesn’t noticeably change the overall skin bacteria or make harmful Strep bacteria grow better. Adding strong antimicrobials like benzalkonium chloride or triclocarban to soap can actually cut down Strep growth after washing. So normal hand‑washing stays beneficial, and extra antimicrobial additives might help if you’re targeting specific pathogens.