An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
LL-37 is a human peptide that can kill many bacteria and stop bio‑films, but it’s pricey, breaks down quickly in the body, works less well in normal fluids, and can be toxic to human cells. Researchers are looking at ways to make it more useful, like attaching it to surfaces, packaging it in special carriers, tweaking its sequence, or using it together with other drugs. For now, the plain peptide isn’t ready for home use, but the ideas for improving it could guide future DIY experiments.
Wuersching. Sabina Noreen SN; Huth. Karin Christine KC; Hickel. Reinhard R; Kollmuss. Maximilian M
The study shows that the natural peptide LL‑37 can strongly stop the growth and biofilm buildup of bacteria that cause cavities and gum disease, while a similar peptide, lactoferricin, does not work well. This suggests LL‑37 might become a useful ingredient in future mouth‑wash or gel products, but more research is needed before it’s safe to try on your own.
The study shows that the human antimicrobial peptide LL‑37 not only kills group A strep bacteria but also helps the immune system by activating certain cell receptors. A bacterial enzyme can cut LL‑37, which stops these immune‑boosting effects even though the peptide still kills bacteria. Modified versions of LL‑37 that resist this cutting keep both killing and immune‑activating functions, leading to better infection clearance in mice.
Porter. Ross J RJ; Murray. Graeme I GI; Alnabulsi. Abdo A; Humphries. Matthew P MP; James. Jacquelin...
Researchers found that lower levels of the natural peptide LL-37 in colon cells are linked to more advanced colorectal cancer and fewer CD8+ T‑cells, while mice without LL-37 develop larger tumors. In human tumor samples, loss of LL-37 appears early and is tied to tumor characteristics, but it didn’t affect gut barrier genes.
Mori. Takeshi T; Yoshida. Miyako M; Hazekawa. Mai M; Ishibashi. Daisuke D; Hatanaka. Yoshiro Y; Naga...
Scientists linked a short piece of the human antimicrobial peptide LL‑37 to a biodegradable polymer (PLGA) and found the combo killed common bacteria and yeast better than the peptide alone, without damaging red blood cells. This shows a way to make stronger, safer antimicrobial agents, but it’s still early‑stage lab work.
Zhang. Jiawen J; Jiang. Peiyu P; Sheng. Lei L; Liu. Yunyi Y; Liu. Yixuan Y; Li. Min M; Tao. Meng M;...
A study found that the blood pressure drug carvedilol can improve rosacea skin flare-ups by lowering a skin‑immune trigger called LL‑37. It does this by blocking a receptor (TLR2) on immune cells, which reduces inflammation and redness over several months of treatment.
Yu. Jie J; Dai. Yue Y; Fu. Yuxuan Y; Wang. Kezhen K; Yang. Yang Y; Li. Min M; Xu. Wei W; Wei. Lin L
The study shows that the human peptide LL‑37 (and its mouse version CRAMP) can curb infection by Enterovirus 71, a common non‑enveloped virus, by boosting the cell’s antiviral defenses and stopping the virus from attaching to cells. It isn’t directly killing the virus but helps the immune response and reduces inflammation. While the work is done in mouse tissue and cultured brain cells, it suggests LL‑37 might be a useful antiviral tool, though real‑world dosing and safety are still unknown.
Adding bovine lactoferrin to infant formula (about 76 mg per 100 g of formula) cut down diarrhea and respiratory infections and raised the body’s natural antimicrobial peptide LL‑37, along with other immune markers. The higher dose worked better than a lower dose or no lactoferrin.
Bleakley. Amy S AS; Licciardi. Paul V PV; Binks. Michael J MJ
Vitamin D helps the body’s first‑line immune cells recognize and fight common kids’ lung bugs by boosting the antimicrobial peptide LL‑37 and tweaking receptors and inflammation signals, but all the data come from lab dishes, not real children.
The study shows that an herbal extract from Coptis chinensis can block the skin enzymes that turn an inactive protein into the active inflammatory peptide LL‑37, which is a key driver of rosacea. By doing this, the extract also lowers inflammation signals and reduces blood‑vessel growth that cause redness. For DIY health enthusiasts, this suggests a natural, topical way to calm rosacea‑related skin flare‑ups.
The study found that vitamin A (as retinoic acid) boosts the production of antimicrobial peptides like LL‑37 and other immune signals in airway cells, helping kill TB bacteria there, while vitamin D (calcitriol) works better in immune cells. Together they may improve overall defense against TB.
Acen. Ester Lilian EL; Biraro. Irene Andia IA; Worodria. William W; Joloba. Moses L ML; Nkeeto. Bill...
People with active lung TB tend to have low vitamin D levels and higher amounts of the immune peptide LL‑37 in their blood, while the local lung tissue shows less LL‑37. This pattern suggests that low vitamin D may weaken the body's defense against TB, and that boosting vitamin D could help protect against the disease.
In lab tests, adding active vitamin D3 and a compound called phenylbutyrate helped human immune cells kill drug‑resistant TB bacteria better, and it also made standard TB drugs work more strongly, likely by boosting the body's own antimicrobial peptide LL‑37 and cell‑cleaning processes.
A lab study found that the synthetic peptide D‑LL‑31 can boost the power of common sinus infection antibiotics (amoxicillin and tobramycin) against stubborn bacterial biofilms, while appearing safe for lung cells at low concentrations.
Scientists discovered that the human antimicrobial peptide LL-37 can group together into a four‑unit channel that punches holes in bacterial membranes, letting water and ions pass and killing the bugs. This structural insight helps explain how LL-37 works and points to ways to make stronger versions.
Yang. Xue X; Niu. Li L; Pan. Yaping Y; Feng. Xianghui X; Liu. Jie J; Guo. Yan Y; Pan. Chunling C; Ge...
The study shows that the natural antimicrobial peptide LL‑37 can kill the gum‑disease bacterium P. gingivalis that hides inside skin cells by turning on the cells' own recycling system (autophagy). When autophagy was blocked, LL‑37 was less effective, indicating its action depends on this pathway.
A study in mice and cell cultures showed that a plant compound called cinnamtannin B1 (CB1) can calm down skin inflammation caused by the antimicrobial peptide LL‑37, which is linked to rosacea. CB1 reduced redness, immune cell buildup, and the inflammatory signal IL‑8 by blocking a specific step (ERK phosphorylation) in the cell’s MAPK signaling pathway.
The paper shows that a short piece of the human antimicrobial peptide LL‑37 (the 17‑29 segment) can stack together into stable, helical fibrils that kill bacteria by breaking their membranes, and that this self‑assembly is crucial for its activity, hinting at new ways to make durable antimicrobial materials.
The study shows that cells in the gums (periodontal ligament cells) can act like immune cells and release inflammation signals when they encounter bacterial toxins. Two natural substances—vitamin D and the antimicrobial peptide LL‑37—can dampen this inflammatory response, similar to how steroids work. This suggests that boosting LL‑37 (or vitamin D) might help keep gums healthier and reduce inflammation.
Miramontes. Claudia Valdez CV; Rodríguez-Carlos. Adrián A; Marin-Luévano. Sara P SP;...
The study shows that nicotine, the main active chemical in cigarettes, can weaken the lung's natural defenses by lowering the production of antimicrobial peptides like LL-37, HBD‑2, and HBD‑3. This reduction lets the tuberculosis bacteria grow more easily inside certain lung cells.