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 the natural peptide LL‑37, which our skin makes during bacterial infections, can make mast cells more alert by increasing a receptor (TLR4) and releasing immune signals. When bacteria are present, LL‑37 pushes mast cells toward a stronger innate immune response, but it also triggers some allergy‑related signals that are blocked by bacterial components. This suggests LL‑37 acts like an alarm for the immune system, but the work was done in cells, not people, so it doesn’t give a clear way to use it as a supplement or therapy yet.
den Hertog. Alice L AL; van Marle. Jan J; Veerman. Enno C I EC; Valentijn-Benz. Marianne M; Nazmi. K...
The human antimicrobial peptide LL-37 and some shortened versions can stick to the surface of the fungus Candida albicans, and even move inside some cells, causing the fungal membrane to split into separate regions and leak out small proteins and other cell parts. This shows the peptide can kill or weaken the fungus, but the study doesn’t give dosage or safety info for humans.
Kandler. Kerstin K; Shaykhiev. Renat R; Kleemann. Peter P; Klescz. Frank F; Lohoff. Michael M; Vogel...
The natural peptide LL‑37, which normally helps kill microbes, also calms down key immune cells called dendritic cells. When LL‑37 is present, these cells show fewer activation signals and release less inflammatory chemicals, which then leads to weaker T‑cell responses.
Thwaite. Joanne E JE; Hibbs. Stephen S; Titball. Richard W RW; Atkins. Timothy P TP
The study shows that the human antimicrobial peptide LL‑37 is broken down by a protein‑making enzyme from the dangerous bacterium Bacillus anthracis, which makes the bacteria more resistant to LL‑37’s killing effect. Other Bacillus species are less resistant. This suggests that LL‑37’s usefulness could be limited when certain bacteria produce degrading enzymes.
Erhart. W W; Alkasi. Ö Ö; Brunke. G G; Wegener. F F; Maass. N N; Arnold. N N; Arlt. A A; M...
In women with genital warts caused by low‑risk HPV, the body naturally ramps up several beta‑defensins (hBD‑1, hBD‑2, hBD‑3) and a protein called psoriasin, but it does not increase the antimicrobial peptide LL‑37. This suggests LL‑37 isn’t a key player in fighting these lesions, while beta‑defensins may be more important.
Zhang. Zhifang Z; Cherryholmes. Gregory G; Chang. Frances F; Rose. David M DM; Schraufstatter. Ingri...
The study shows that the natural peptide LL‑37 can bind to and activate the CXCR2 receptor on human neutrophils, triggering calcium signals and cell movement, similar to known chemokines. This reveals a new way LL‑37 may influence immune responses, but the work is purely lab‑based and does not give dosing or safety guidance for taking LL‑37 as a supplement.
Ballardini. N N; Johansson. C C; Lilja. G G; Lindh. M M; Linde. Y Y; Scheynius. A A; Agerberth. B B
People with atopic eczema have more of the natural skin peptide LL‑37 in the itchy, inflamed patches than in the unaffected skin, but the amount doesn't track with how bad the eczema is. Healthy skin and the non‑itchy areas of eczema patients have similar LL‑37 levels. The peptide shows up whenever the skin is damaged, hinting it may help with wound healing.
Mookherjee. Neeloffer N; Rehaume. Linda M LM; Hancock. Robert E W RE
The study talks about natural and synthetic peptides like LL‑37 and IDR‑1 that can calm down harmful inflammation during severe infections without directly killing bacteria. They work by blocking toxic bacterial components and tweaking the immune response, which could make them useful for treating sepsis in the future, but they aren’t ready for personal use yet.
Chung. W O WO; Dommisch. H H; Yin. L L; Dale. B A BA
The paper shows that the cells lining your gums make natural antibiotics called LL‑37 and defensins, which help keep the mouth healthy by fighting bacteria, fungi, and viruses. Understanding how these peptides work could lead to new ways to prevent or treat gum disease, but the study doesn’t give a specific supplement or dosage to try now.
Neville. Frances F; Gidalevitz. David D; Kale. Girish G; Nelson. Andrew A
The study used an electric‑based test to see how the human antimicrobial peptide LL‑37 sticks to different membrane‑like fats. It barely affects a common cell‑membrane fat (DOPC), slightly affects a negatively‑charged fat (DOPG) and a bacterial component (lipid A), and strongly affects a pure lipid A layer, confirming LL‑37’s ability to disrupt bacterial membranes.
Felgentreff. Kerstin K; Beisswenger. Christoph C; Griese. Matthias M; Gulder. Tanja T; Bringmann. Ge...
The study shows that the natural antimicrobial peptide LL‑37 sticks to the sticky proteins (mucins) in airway mucus because they have opposite charges. This binding changes the shape of LL‑37 and makes it less able to kill common lung bacteria. In real human airway samples, a good chunk of LL‑37 is already stuck to these big mucus molecules, meaning its activity can be dampened by the mucus itself.
Flamand. Louis L; Tremblay. Michel J MJ; Borgeat. Pierre P
The study shows that the immune signaling molecule leukotriene B4 (LTB4) can make white blood cells release natural antibiotics like LL‑37, which then kill bacteria and viruses in lab tests and also boost antimicrobial activity in monkey blood.
Brandenburg. Lars-Ove LO; Varoga. Deike D; Nicolaeva. Nicoletta N; Leib. Stephen L SL; Wilms. Henrik...
The study shows that the antimicrobial peptide LL-37 (and its rat equivalent) is produced by brain support cells (glia) during bacterial meningitis and can kill bacteria in the spinal fluid. This suggests the body’s own immune system uses LL-37 in the brain to fight infection.
Srivastava. Maya D MD; Thomas. Anil A; Srivastava. B I S BI; Check. Jerome H JH
The study shows that progesterone can boost the production of the immune‑modulating protein PIBF and the antimicrobial peptide LL‑37 in certain leukemia cell lines, while the drug mifepristone does the opposite. This suggests hormones can affect innate immunity, but the work was done in cancer cells in a lab, not in healthy people.
The study shows that proteins from Staph bacteria can activate a receptor (TLR2) on eye cells, leading those cells to produce more of the natural antimicrobial peptide LL‑37 along with other immune signals. This tells us that the body’s own LL‑37 can be turned on by certain bacterial components, but the work was done in lab-grown corneal cells, not in whole people.
Tai. Emily K K EK; Wong. Helen P S HP; Lam. Emily K Y EK; Wu. William K K WK; Yu. L L; Koo. Marcel W...
In lab-grown human colon cells, the antimicrobial peptide LL‑37 boosted the production of protective gut mucus by turning on the MUC1 and MUC2 genes through a MAP‑kinase signaling route. The effect was seen at concentrations of 10‑40 µg/ml, but the study was done only in cells, not in people, and it doesn’t show how to safely deliver LL‑37 as a supplement.
McDonald. V V; Pollok. R C G RC; Dhaliwal. W W; Naik. S S; Farthing. M J G MJ; Bajaj-Elliott. M M
The study shows that when gut cells are infected with a parasite, they make more of a signaling molecule called IL‑18, which then ramps up the production of the natural antibiotic peptide LL‑37. This boost in LL‑37 helps slow down the parasite’s growth inside the cells. The work was done in lab cell lines, not in people, so it’s an early hint rather than a ready‑to‑use hack.
Peyret-Lacombe. A A; Duplan. H H; Watts. M M; Charveron. M M; Brunel. G G
Scientists built a lab-grown gum lining that looks and acts like real gum tissue. It shows the same cell markers and can make natural antimicrobial proteins like LL‑37 when exposed to inflammation signals, meaning it’s a good stand‑in for studying mouth immunity.
Vonk. Marcel J MJ; Hiemstra. Pieter S PS; Grote. Jan J JJ
A lab study showed that a synthetic version of the natural peptide LL‑37, called P60.4‑Ac, can block the harmful inflammation caused by bacterial components (LPS and LTA) in airway cells, reducing swelling that’s linked to ear and sinus infections.
Coffelt. Seth B SB; Tomchuck. Suzanne L SL; Zwezdaryk. Kevin J KJ; Danka. Elizabeth S ES; Scandurro....
The antimicrobial peptide LL-37, which is naturally made in the body, can make ovarian cancer cells grow more aggressively by helping them invade surrounding tissue. It does this through a receptor called FPRL1 and activates several cell signaling pathways. However, LL-37 does not seem to boost cancer cell proliferation via that same receptor.