An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Gupta. Kshitij K; Subramanian. Hariharan H; Ali. Hydar H
The study shows that short versions of the immune‑boosting peptide LL‑37 (called FK‑13) and a modified defensin (CHRG01) can still trigger mast cells, which help fight infections, and unlike the full‑length peptides they aren’t blocked by bacterial LPS. This means these tiny peptides might work better against stubborn, antibiotic‑resistant bugs, but the research is still early and doesn’t give dosing or safety details.
Malik. Erum E; Dennison. Sarah R SR; Harris. Frederick F; Phoenix. David A DA
This review talks about natural antibiotics called antimicrobial peptides that work best in acidic places like the skin. One of these peptides, LL‑37, has been tested in humans and can help heal wounds, fight infections, and even target some cancers when applied on the surface of the body.
Fan. Di D; Coughlin. Laura A LA; Neubauer. Megan M MM; Kim. Jiwoong J; Kim. Min Soo MS; Zhan. Xiaowe...
The study shows that good gut bacteria help the body make the antimicrobial peptide LL‑37 (called CRAMP in mice) via the HIF‑1α pathway, which blocks harmful Candida yeast from taking hold. Turning on HIF‑1α with drugs reduced yeast levels and death in mice, and antibiotics that kill gut microbes made the mice vulnerable. For biohackers, this suggests that keeping a healthy, anaerobic gut microbiome (e.g., with certain probiotics or fiber) and avoiding unnecessary antibiotics could boost natural antifungal defenses, and that compounds that activate HIF‑1α (like some dietary phytochemicals or vitamin D) might further enhance LL‑37 production.
Brannon. John R JR; Thomassin. Jenny-Lee JL; Gruenheid. Samantha S; Le Moual. Hervé H
The study shows that the shape of the antimicrobial peptide LL‑37 matters: when it stays in its natural alpha‑helix form it’s harder for certain bacterial enzymes to cut it, but if its helix is disrupted the enzymes break it down faster.
Tang. Xiao X; Basavarajappa. Devaraj D; Haeggström. Jesper Z JZ; Wan. Min M
The study shows that the human antimicrobial peptide LL‑37 can be pulled into immune cells called macrophages, and this uptake depends on a receptor called P2X7. Once inside, LL‑37 goes to the cell’s waste‑disposal compartments and helps kill bacteria, boosting the cell’s ability to clear infections.
Ogunsakin. Olalekan O; Hottor. Tete T; Mehta. Ashish A; Lichtveld. Maureen M; McCaskill. Michael M
The study found that people with chronic heavy drinking have lower levels of both inactive and active vitamin D in their lungs, which leads to a drop in the antimicrobial peptide LL-37. This drop may help explain why heavy drinkers get more and worse respiratory infections.
Zhang. Chong C; Zhao. Lianrong L; Ding. Yang Y; Sheng. Qiuju Q; Bai. Han H; An. Ziying Z; Xia. Tingt...
People with liver cirrhosis often lack vitamin D, which weakens a natural antibacterial peptide called LL‑37. In lab tests, adding vitamin D restored LL‑37 levels dramatically, especially after about 36 hours, suggesting that vitamin D can boost the immune defense against infections like spontaneous bacterial peritonitis in these patients.
A lab study found that shining red LED light (625 nm) on gum cells infected with the bad bacteria P. gingivalis makes the natural antimicrobial peptide LL‑37 work better and cuts down inflammation, suggesting red light could help keep gums healthier.
The review shows that the antimicrobial peptide LL‑37 changes shape depending on pH, which can help it carry and release genetic material inside cells, and that many peptides only work well under certain conditions like low oxygen or specific acidity. It also notes that using peptide mixes rather than a single peptide works better against stubborn bacterial films.
Svensson. Daniel D; Nebel. Daniel D; Voss. Ulrikke U; Ekblad. Eva E; Nilsson. Bengt-Olof BO
The study shows that the active form of vitamin D (calcitriol) can dramatically boost the skin's production of the antimicrobial peptide LL‑37, but it needs a partner protein called RXRα to work. This effect happens without increasing the amount of vitamin‑D receptors themselves.
Podolnikova. Nataly P NP; Podolnikov. Andriy V AV; Haas. Thomas A TA; Lishko. Valeryi K VK; Ugarova....
Scientists found that the immune‑cell receptor Mac‑1 likes to grab short, positively‑charged protein pieces that have nearby oily (hydrophobic) parts. The human antimicrobial peptide LL‑37 fits this pattern, so it sticks to Mac‑1, making neutrophils move and become active. This shows LL‑37 can act like an “alarm” signal for the immune system.
LL-37 is a natural human peptide that can kill sperm and many STI‑causing microbes. It seems to target sperm without harming the vaginal lining and has worked as a sperm killer in mouse tests, making it a promising candidate for a future vaginal gel that both prevents pregnancy and infections.
Pazmandi. Kitti K; Agod. Zsofia Z; Kumar. Brahma V BV; Szabo. Attila A; Fekete. Tunde T; Sogor. Vikt...
The study shows that when mitochondrial DNA (mtDNA) gets damaged by oxidative stress, it becomes a stronger trigger for immune cells called plasmacytoid dendritic cells. This effect is even bigger when the mtDNA teams up with the natural antimicrobial peptide LL‑37, which then can spark production of interferon‑alpha, a key immune signal. Blocking the DNA‑sensing receptor TLR9 stops these reactions, highlighting its role in the process.
People with tuberculosis, especially those who also have diabetes, often have low vitamin D levels. Their bodies show higher levels of the antimicrobial peptide LL‑37 and certain immune signals (IFN‑γ, IL‑4, IL‑17), likely as a response to the infection. The study suggests that giving vitamin D could help these patients, and that LL‑37 and the immune signals might serve as markers of disease activity.
Huo. Y Y; Wang. F F; Sun. B B; Yin. L R LR; Zhang. P P PP; Zhang. Y J YJ; Zhang. B M BM
Researchers made a lab‑produced version of the natural peptide LL‑37 and showed it can slow down Candida yeast growth in a dish that mimics the vagina. The peptide also boosted a “good” immune signal (IFN‑γ) and lowered an anti‑inflammatory signal (IL‑10), which together may help the tissue fight infection.
Ramos. N L NL; Sekikubo. M M; Kironde. F F; Mirembe. F F; Sääf. M M; Brauner. A A
During pregnancy, women's vitamin D levels naturally rise, which also boosts the antimicrobial peptide LL-37. Higher vitamin D and LL-37 make the blood better at stopping E. coli, a common cause of urinary infections. The study shows vitamin D can tweak immune signals in bladder cells, suggesting a protective effect.
Bourgade. Karine K; Garneau. Hugo H; Giroux. Geneviève G; Le Page. Aurélie Y AY; Bocti. Ch...
The study found that the natural antimicrobial peptide LL‑37 can stop the herpes simplex virus‑1 (HSV‑1) from infecting cells, even if it’s added after the virus is present, unlike beta‑amyloid peptides which only work if they’re there before the virus. This effect was seen in lab-grown cells and in a test‑tube system, showing LL‑37 directly blocks the virus from entering cells.
Kunz. Hawley H; Bishop. Nicolette C NC; Spielmann. Guillaume G; Pistillo. Mira M; Reed. Justin J; Og...
The study shows that after a 30‑minute bike ride, the amount of antimicrobial proteins in saliva—including the peptide LL‑37—goes up, and this boost is much bigger in people who are already very fit. Fit cyclists start with lower baseline levels but see a sharp rise after exercise, suggesting that regular high‑intensity training can enhance the body’s natural defenses in the mouth and throat.
Afsal. K K; Harishankar. M M; Banurekha. V V VV; Meenakshi. N N; Parthasarathy. R T RT; Selvaraj. P...
The study shows that the active form of vitamin D can boost the body's natural antimicrobial peptide LL‑37 and improve immune cell activity, especially in people with milder tuberculosis, suggesting vitamin D could help the body fight infections faster.
Kumaraswamy. Monika M; Lin. Leo L; Olson. Joshua J; Sun. Ching-Fang CF; Nonejuie. Poochit P; Corride...
The study found that azithromycin, a common antibiotic, can actually kill the drug‑resistant bug Stenotrophomonas maltophilia when tested in conditions that mimic human tissue fluids, and its effect is boosted when combined with the cationic peptide colistin or the natural human peptide LL‑37. This synergy works because the peptides help the drug get inside the bacteria. In mouse lungs and human neutrophil tests, azithromycin also made the bacteria easier for the immune system to clear.