An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
Sahariah. Priyanka P; Benediktssdóttir. Berglind E BE; Hjálmarsdóttir. Martha Á...
The study shows that modifying chitosan with longer alkyl chains makes it better at killing bacteria but also more toxic to human cells. These chitosan compounds were compared to common disinfectants and the antimicrobial peptide LL‑37, and they were found to be more selective—killing bacteria while sparing human cells better than LL‑37 and the disinfectants. However, the research is about a lab‑made polymer, not a supplement or peptide you can take, so it offers limited direct actions for biohackers.
Choi. Heejun H; Yang. Zhilin Z; Weisshaar. James C JC
The study shows that the human antimicrobial peptide LL‑37 (and a lab‑made peptide called CM15) kills bacteria by causing a rapid burst of harmful oxygen molecules inside the cells, but this only works well when the bacteria are using oxygen for energy.
The gum lining makes natural antibiotics like LL‑37 that fight mouth bugs, help heal wounds, and even affect blood flow. While we know these peptides are useful for oral health, the paper doesn’t give any dosing or DIY tips, just explains how they work and why they might become future medicines.
Di Grazia. Antonio A; Cappiello. Floriana F; Imanishi. Akiko A; Mastrofrancesco. Arianna A; Picardo....
A frog‑skin peptide called esculentin‑1a(1‑21)NH2 helps human skin cells move faster to close wounds in lab dishes, doing this better than the human peptide LL‑37. It works by turning on the skin’s growth‑factor receptor and a signaling protein, and it still kills harmful bacteria like Pseudomonas without hurting human cells. However, the work is only in cell cultures, so it isn’t ready for home use yet.
In mice, a snake‑venom peptide called cathelicidin‑BF given before a bacterial toxin protected the gut lining, kept the barrier tight, and lowered inflammation.
The research shows that the body’s natural antimicrobial peptide LL‑37 can kill the sexually transmitted bacteria Chlamydia trachomatis, but the bacteria release an enzyme called CPAF that breaks down LL‑37, stopping its action and helping the infection spread.
In mice with severe infection, giving the natural human peptide LL-37 helped them live longer. It did this by stopping a type of inflammatory cell death (pyroptosis) in immune cells, calming down harmful cytokine storms, and killing bacteria. The work shows LL-37 has multiple useful actions against sepsis, but it’s still an early‑stage animal study.
Kim. Ji Young JY; Kim. Yoon Jee YJ; Lim. Beom Jin BJ; Sohn. Hyo Jung HJ; Shin. Dongyun D; Oh. Sang H...
The study shows that a skin protein called cathelicidin (LL‑37) is higher in rosacea‑affected skin and that turning on a skin receptor called PAR‑2 makes cells produce even more cathelicidin and a growth factor (VEGF). While PAR‑2 itself isn’t higher overall in rosacea skin, its activity is linked to the excess cathelicidin that may drive inflammation.
In mice that can’t make the antimicrobial peptide cathelicidin (the mouse version of human LL‑37), bladder infections with E. coli were milder, with fewer bacteria and quicker healing. The peptide, while able to kill bacteria in a dish, actually made the bladder lining more welcoming to the bugs and caused stronger inflammation in live animals.
Svensson. Daniel D; Wilk. Laura L; Mörgelin. Matthias M; Herwald. Heiko H; Nilsson. Bengt-Olof...
LL-37 is a natural peptide that can kill microbes but can also harm our own cells if its levels get too high. The study found that a protein called p33 (also known as gC1qR) inside cells can bind LL-37 and protect the cells from this damage. More p33 means cells survive better when exposed to LL-37, while less p33 makes them more vulnerable.
Gad. Ghada I GI; Abushady. Nancy M NM; Fathi. Marwa S MS; Elsaadany. Wafaa W
In newborns with congenital pneumonia, the natural antimicrobial peptide LL‑37 was much higher while vitamin D levels were lower than in healthy babies. Higher LL‑37 linked to poorer early health scores and longer hospital stays, and a level above 17 pg/mmol could reliably flag the infection.
Honda. Jennifer R JR; Hess. Tamara T; Malcolm. Kenneth C KC; Ovrutsky. Alida R AR; Bai. Xiyuan X; Ir...
The study shows that certain lung‑infecting bacteria called nontuberculous mycobacteria (NTM) can shrug off the human antimicrobial peptide LL‑37 and even neutralize it with their own lipids, meaning LL‑37 isn’t effective against these bugs and might even help them grow in some cases.
de la Fuente-Núñez. César C; Hancock. Robert E W RE
Scientists are studying tiny proteins like LL‑37 that can stop harmful bacteria from forming protective layers called biofilms, which make infections harder to treat. By tweaking these proteins, they’ve made even stronger versions that work well with regular antibiotics and break down a bacterial signal molecule needed for biofilm growth. The research is still early and mostly lab‑based, so it isn’t a ready‑to‑use treatment yet, but it points to future ways to fight stubborn infections.
Scientists found that a gut‑lining cell type called M cells has the ATP‑sensing P2X7 receptor, and that the antimicrobial peptide LL‑37 can activate this receptor to boost local immune activity. This is an early‑stage discovery showing a possible way the gut’s immune system can be tuned by molecules like LL‑37, but it doesn’t give dosing or practical tips yet.
Hindler. Janet A JA; Wong-Beringer. Annie A; Charlton. Carmen L CL; Miller. Shelley A SA; Kelesidis....
The study shows that adding the antibiotic ampicillin to daptomycin makes the combo work better against tough, drug‑resistant gut bacteria, and it also helps the body’s own antimicrobial peptide LL‑37 kill these bugs. However, this is lab work, not a proven treatment you can use at home.
Rodríguez-Rojas. Alexandro A; Makarova. Olga O; Müller. Uta U; Rolff. Jens J
The study shows that the antimicrobial peptide LL‑37 only makes bacteria mutate more when there is also free iron around. Together they let iron get into the bacterial cells, causing DNA damage through Fenton chemistry, which shows up as specific C‑to‑T changes. Without iron, LL‑37 alone doesn’t boost mutation rates.
Margalit. Anatte A; Kowalczyk. Michał J MJ; Żaba. Ryszard R; Kavanagh. Kevin K
The paper explains that people with rosacea have higher levels of a natural peptide called LL‑37, more of the immune sensor TLR‑2, and extra vitamin D3 in their skin. These changes make the skin overly reactive to things like UV light and to tiny mites (Demodex) that live on the face, which can worsen the rash.
Sutton. Morgan T MT; Fletcher. David D; Ghosh. Santosh K SK; Weinberg. Aaron A; van Heeckeren. Rolf...
The study shows that human mesenchymal stem cells (MSCs) can release the antimicrobial peptide LL‑37, which helps slow the growth of several bacteria and makes antibiotics work better. The strength of this effect depends on where the MSCs come from and whether the CFTR protein is working properly.
McEachern. Elisa K EK; Hwang. John H JH; Sladewski. Katherine M KM; Nicatia. Shari S; Dewitz. Carola...
Smoking creates chemicals that make the dangerous bacteria MRSA harder for our bodies to kill, even weakening a natural antimicrobial protein called LL‑37, which can lead to more severe infections.
Guthrie. Brandon L BL; Introini. Andrea A; Roxby. Alison C AC; Choi. Robert Y RY; Bosire. Rose R; Lo...
A study in Kenyan women found that using the injectable birth control DMPA raises levels of the natural antimicrobial peptide LL‑37 (and a few other immune proteins) in vaginal secretions, while not changing some others. This suggests DMPA changes the local immune environment, which might influence how easily infections like HIV can take hold, but the exact impact is still unclear.