An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
The study shows that while both a natural fragment of LL‑37 (GF‑17) and a more stable engineered version (17BIPHE2) kill bacteria equally well in simple lab tests, the stable peptide works better against tough biofilm infections and protects insects from deadly MRSA. Using a nanofiber or microneedle patch can shield any peptide from breakdown, making even the less stable version effective in wound healing.
Lv. Pingping P; Zhang. Huirong H; Tai. Meiling M; Che. Biao B; Yu. Dan D; Zhang. Ying Y; Li. Haodong...
A lab study found that oil from Schisandra chinensis fruit, rich in five lignan compounds, can calm skin cells inflamed by acne bacteria. In human skin cell cultures, the oil lowered inflammation signals, reduced harmful reactive oxygen species, blocked calcium influx, and decreased the antimicrobial peptide LL‑37, which is linked to skin irritation. While the work is only in cells, it hints that Schisandra oil might be a useful anti‑acne or anti‑inflammatory ingredient in topical skin products.
Siew. Ruth R; Ou. Tzung-Lin TL; Dahesh. Samira S; Akong. Kathryn K; Nizet. Victor V
The paper shows that adding sodium bicarbonate makes the lung‑killing peptide LL‑37 work better against Pseudomonas and helps immune cells destroy the bacteria more efficiently, also boosting the formation of NETs. This suggests that raising airway bicarbonate (e.g., with low‑dose nebulized or oral sodium bicarbonate) could be a simple way to improve lung defenses, especially for people with cystic fibrosis or chronic lung infections, though it’s not yet proven in large human trials.
Researchers made a lab‑produced version of the human peptide LL‑37 and showed it can quickly kill the dangerous bacteria Acinetobacter baumannii in test tubes and save mice with a bloodstream infection, with no bacteria left in their blood.
The study shows that the natural peptide LL‑37 can grab the immune‑activating molecule cGAMP and carry it into cells, boosting the body’s antiviral defenses via the STING pathway. It also finds that taking vitamin D3 or sodium butyrate can raise LL‑37 levels, potentially enhancing this effect. For DIY health enthusiasts, this suggests that supporting LL‑37 production with safe, everyday supplements might improve innate immunity, though direct use of LL‑37 itself isn’t yet a practical option.
Aloul. Karim M KM; Nielsen. Josefine Eilsø JE; Defensor. Erwin B EB; Lin. Jennifer S JS; Fortko...
The paper proposes that boosting the natural peptide LL‑37—using vitamin D and other safe compounds—might help calm the over‑active immune response seen in severe COVID‑19, clear harmful clots, protect blood vessels, support insulin release, and even guard against brain changes linked to Parkinson‑like symptoms. However, the ideas are based on existing knowledge and hypotheses, not on new human trials.
Researchers tested lab-made versions of the natural peptide LL‑37 and found two of them (LL37‑1 and AC‑2) can stop Candida yeast from growing and forming biofilms at very low concentrations in a petri‑dish. This shows the peptides have strong antifungal power, but the work is still only in test‑tube experiments, not in people.
Zhuo. Haiwei H; Zhang. Xi X; Li. Maogen M; Zhang. Qian Q; Wang. Yonglan Y
Researchers found that a short piece of the natural peptide LL-37, called KR-12-3, can kill the mouth bacteria Streptococcus gordonii and calm down inflammation in lab cells, while staying mostly non‑toxic. This suggests it could become a new kind of mouth rinse or implant coating to prevent gum infection around dental implants, but it’s still early‑stage lab work.
The study shows that the antimicrobial peptide LL‑37 can cut dengue virus replication in immune cells if it’s present at the same time as the virus, and it can calm inflammation and boost antiviral genes when added after infection. Vitamin D helps cells make more of their own LL‑37, suggesting that good vitamin D levels might strengthen natural defenses against dengue and possibly other viruses.
Jelodari. Sahar S; Daemi. Hamed H; Mohammadi. Parvaneh P; Verdi. Javad J; J Al-Awady. Mohammed M; Ai...
Scientists made a skin‑like gel that slowly releases the antimicrobial peptide LL‑37. In rats with deep skin wounds, the gel helped skin cells grow, killed both Gram‑negative and Gram‑positive bacteria, and sped up healing so that wounds were almost completely closed by three weeks. Blood‑vessel growth in the wound area was also higher, which supports better tissue repair.
Zhao. Yiming Y; Zhang. Hanlin H; Zhao. Zhizhuang Z; Liu. Fangfang F; Dong. Meng M; Chen. Li L; Shen....
A clinical trial gave COVID‑19 patients a pill containing the antimicrobial peptide LL‑37 made by a friendly bacteria. When the pill was started within six days of diagnosis, patients cleared the virus about five days faster than those who got a placebo, and no serious side effects were seen.
Ramírez-Ledesma. María G MG; Rodríguez. Mayra C MC; Alva-Murillo. Nayeli N; Avila. Ev...
Researchers found that the human antimicrobial peptide LL‑37 and its shorter versions can kill the parasite that causes trichomoniasis, even strains that resist the usual drug metronidazole. The smallest piece, KR‑20, worked best, and mixing low amounts of these peptides with metronidazole made the drug work better against both sensitive and resistant parasites. This is early‑stage lab work, so it isn’t a ready‑to‑use treatment yet, but it hints that peptide‑based supplements could boost standard therapy in the future.
Scientists found that the way two antimicrobial peptides (LL-37 and HNP1) work together depends a lot on the type of lipids in the target cell membrane. By mimicking the lipid makeup of human cells versus E. coli bacteria, they could partly reproduce the enhanced killing effect, suggesting that simple lipid‑peptide interactions drive the synergy.
Zhao. Shaojie S; He. Yixiu Y; Pan. Menglan M; Chen. Bingzhang B; Zhang. Siqi S; Zhang. Yufeng Y; Zhu...
Kids with bacterial pneumonia tend to have low vitamin D, and the worse the illness, the lower their vitamin D and the antimicrobial peptide LL‑37 get, even though LL‑37 is initially higher during infection. Higher vitamin D levels are linked to higher LL‑37 and shorter hospital stays, suggesting vitamin D helps the body’s natural defenses.
LL-37 is a natural human peptide that not only fights infections but also can influence cancer cells, sometimes slowing tumor growth and other times helping it, depending on the situation. Researchers are reviewing how its smaller pieces and modified versions can kill cancer cells and are working on ways to deliver it directly to tumors, but no clear home‑use protocol exists yet.
Taking vitamin D pills for six weeks raised kids' blood vitamin D levels, cut their eczema severity, and boosted the skin's natural antimicrobial peptide LL‑37, especially in the rash areas. This shows oral vitamin D can help skin health by turning on the vitamin D receptor and cathelicidin.
Santana. Felix L FL; Estrada. Karel K; Alford. Morgan A MA; Wu. Bing C BC; Dostert. Melanie M; Pedra...
Researchers found a new peptide from alligators, called As-CATH8, that kills tough bacteria like MRSA and Acinetobacter much better than the human peptide LL‑37 and even matches powerful antibiotics in lab tests and mouse skin infection models.
This review explains that the natural peptide LL‑37, along with other antimicrobial proteins, is already made by the fetus and newborn and helps fight early infections like sepsis and necrotizing enterocolitis. It shows that higher or lower levels of these peptides are linked to how bad the infection gets, and scientists are looking at using them as early warning signs or as extra help alongside antibiotics, especially as resistance grows.
Vaccaro. Joseph A JA; Qasem. Ahmad A; Naser. Saleh A SA
The study shows that people with Crohn's disease who have a gut infection (MAP) have lower levels of the immune peptide LL‑37 and the active form of vitamin D (calcitriol). Giving calcitriol (or its precursor calcifediol) boosts LL‑37 production, cuts down the bacteria inside immune cells, and reduces inflammation. This suggests that raising active vitamin D could help the body’s natural defenses, but direct calcitriol use needs medical oversight.