An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
In kids with acute leukemia, higher levels of inflammatory molecules and lower levels of the antimicrobial protein pro‑LL‑37 in the blood before treatment were linked to a greater chance of getting painful mouth sores (oral mucositis) during chemotherapy.
Reynoso-Roldán. Angélica A; Roldán. Maria L ML; Cancino-Diaz. Juan C JC; Rodrígu...
In skin cells grown in the lab, the peptide LL‑37 and a protein called HDAC1 boost the production of VEGF, a factor that promotes new blood vessel growth, while another protein, VHL, reduces VEGF levels. These changes happen through the HIF‑1α pathway, which controls how cells respond to low oxygen.
Kopfnagel. Verena V; Harder. Jürgen J; Werfel. Thomas T
LL-37 and other antimicrobial peptides are found in the skin of people with atopic dermatitis, but they are usually lower than in psoriasis. These peptides can both fight microbes and stir up inflammation, and the allergic‑type signals (Th2 cytokines) in atopic dermatitis can suppress their production, meaning they might not be enough to keep the skin clean.
Zarember. Kol A KA; Marshall-Batty. Kimberly R KR; Cruz. Anna R AR; Chu. Jessica J; Fenster. Michael...
The study shows that the human antimicrobial peptide LL‑37 does not kill the bacteria Granulibacter bethesdensis, which can cause infections in people with immune deficiencies. This pathogen can survive in blood and avoids being killed by immune cells, especially in those lacking proper oxidative killing mechanisms.
Gollwitzer. Hans H; Dombrowski. Yvonne Y; Prodinger. Peter M PM; Peric. Mark M; Summer. Burkhard B;...
Researchers measured the antimicrobial peptide LL-37 (and a few others) in joint fluid and blood to see if it could help tell the difference between infected and non‑infected joint replacements. They found LL-37 was higher in the joint fluid of infected patients and, when combined with certain cytokines, gave fairly good diagnostic accuracy. Blood levels didn’t show the same clear pattern.
The study shows that the human peptide LL‑37 can block a bacterial toxin (LPS) from killing blood‑vessel cells in lab dishes and in mice, which helps protect against severe sepsis. However, this work is still early‑stage animal research and doesn’t give a clear way for everyday people to use the peptide safely or effectively.
Gursoy. Ulvi K UK; Pöllänen. Marja M; Könönen. Eija E; Uitto. Veli-Jukka VJ
The study looked at how a mouth bacteria (Fusobacterium nucleatum) affects the production of natural antimicrobial proteins (hBD‑2, hBD‑3, and LL‑37) in a lab model of gum tissue. It found that the bacteria quickly boost hBD‑2 and hBD‑3, but only cause a weak and limited increase in LL‑37, mainly after longer exposure with one bacterial strain.
Mader. Jamie S JS; Marcet-Palacios. Marcelo M; Hancock. Robert E W RE; Bleackley. R Chris RC
The study found that the human peptide LL‑37 can kill activated killer T‑cells (CD8+ cells) by triggering a type of cell death that involves enzymes called granzymes, while it doesn’t harm resting T‑cells. This suggests LL‑37 can suppress certain immune functions, which could be a concern if you’re trying to boost immunity.
Leung. T F TF; Ching. K W KW; Kong. A P S AP; Wong. G W K GW; Chan. J C N JC; Hon. K L KL
The study found that children with eczema have about the same amount of the immune peptide LL‑37 in their blood as healthy kids, but the amount goes up a bit as eczema gets worse. The link between LL‑37 levels and how bad the eczema is is weak, and it doesn’t relate to skin moisture or water loss.
Scientists made a cheap electronic sensor that can spot the immune peptide LL‑37 in urine, which rises when you have a urinary tract infection. The device uses special electrodes and an antibody to detect LL‑37 down to about 50 µg per milliliter.
The study shows that a type of bacteria (Mycobacterium abscessus) triggers a specific immune alarm system (the NLRP3 inflammasome) in human immune cells, and this process involves the antimicrobial peptide LL‑37 and several signaling proteins. While it explains how the body fights this infection, it doesn’t give direct tips or dosages for using LL‑37 or related compounds to boost health.
McQuade. Rebecca R; Roxas. Bryan B; Viswanathan. V K VK; Vedantam. Gayatri G
The study shows that different strains of the harmful gut bacterium C. difficile react differently to the human immune peptide LL‑37. Some epidemic strains are more resistant, and exposure to low levels of LL‑37 can make the bacteria even tougher by changing the proteins they make.
Schwaab. M M; Gurr. A A; Neumann. A A; Dazert. S S; Minovi. A A
Researchers found that ear wax contains a bunch of natural antimicrobial proteins, including LL‑37, which help keep the ear canal free from infections. Some of these proteins stick to cells in the wax, and together they act as a local defense system. This knowledge could lead to new ear‑specific treatments, but it doesn’t change how you take supplements or affect overall health directly.
Petrov. Velizar V; Funderburg. Nicholas N; Weinberg. Aaron A; Sieg. Scott S
The study looked at how a few immune‑boosting peptides, including LL‑37, affect immune cells. It found that LL‑37 can trigger some signaling molecules, but it’s not as strong as another peptide (hBD‑3). People with HIV showed different immune responses, but the work doesn’t give clear guidance for everyday use.
Goleva. Elena E; Searing. Daniel A DA; Jackson. Leisa P LP; Richers. Brittany N BN; Leung. Donald Y...
The study found that low vitamin D levels are linked to higher inhaled steroid use and weaker response to steroids in kids with asthma, but these links weren’t seen in adults. Vitamin D also seemed to lower allergy‑related IgE in children. LL‑37 levels in the blood rose with higher vitamin D in both age groups.
Researchers found a new genetic change (p.S34N) in the CAMP gene that makes the immune peptide LL‑37 slightly different, and this change is much more common in people with a severe, fast‑progressing gum disease called generalized aggressive periodontitis, but not in regular chronic gum disease or healthy people.
Researchers found that retinal support cells (Muller glia) can detect Staphylococcus aureus through a receptor called TLR2 and respond by making the antimicrobial peptide LL‑37, which can kill the bacteria in lab dishes.
Kapulu. Melissa C MC; Simuyandi. Michelo M; Sianongo. Sandie S; Mutale. Mubanga M; Katubulushi. Max...
In people with Ascaris worm infections, the gut’s natural antibiotic protein LL‑37 (and a few others) is lower than in healthy folks, and this doesn’t bounce back even after the worms are cleared. The infection also shifts immune signals toward a Th1‑type response, which could affect how the body fights other germs and how oral vaccines work.
The study looked at how the natural antimicrobial peptide LL‑37 (and a couple of others) kills Staphylococcus aureus bacteria taken from sick patients versus harmless carriers. It found that LL‑37 works about the same on all the bacteria, with no big differences in how much is needed to stop growth.
Griener. Thomas P TP; Strecker. Jonathan G JG; Humphries. Romney M RM; Mulvey. George L GL; Fuenteal...
Adding a small amount of bacterial LPS makes mice that normally resist Shiga toxin 2 become vulnerable, and while the steroid dexamethasone can block this danger, the antimicrobial peptide LL‑37 does not help at all.