A Peptide for gut infections, immune balance, and wound healing.

LL-37 is a multifunctional host defense peptide. It is called an Antimicrobial peptide or ( AMP). LL-37 has shown potential to serve as an alternative to antibiotics and has antimicrobial activity against gram positive and gram negative human pathogens.

It has activity against bacteria like staphylococcus bacteria, viruses, and fungi.

These and other infections that may be more difficult to clear out are ideal candidates for treatment with LL37. This is because a mucous barrier or biofilm can be present to allow infectious agents to hide out. Think of the thin layer of mucous on plastic that has been left wet outside for days or the film that builds up on dentures. LL-37 breaks down these mucous coverings or biofilms, exposing the invader to the immune system. LL-57 also directly breaks down bacterial cell walls. It has been demonstrated to be useful in treating chronic infections especially in diabetics with compromised immune systems infected with candida albicans (a yeast) and pathogenic E. coli.

There is a cascade of signals that LL-37 uses to interact with many immune cells. It activates the innate mucosal immune defense to clear infectious agents.  Mucosal defense refers to anywhere in the body where there are mucous membranes such as the lining of the intestines, the ureter, genital tracts, and respiratory tract. These areas have significant exposure to the outside world.  Cells that express LL-37 include circulating neutrophils, bone marrow cells, epithelial cells of the skin, cells lining the gastrointestinal tract, the epididymis and lungs.  The production of LL-37 by macrophages is stimulated by Vitamin D released by sunlight through the skin. As so many of these “first contact” cells lining the mucous membranes represent the “front line” of defense, LL-37 plays a very important role released first with inflammation and wounds occurring. It is toxic to both bacterial and normal cells and doesn’t break down very easily with compounds that normally break down proteins.

It can activate and regulate macrophages, monocytes, mesenteric stem cells (MSC), mast cells, neutrophils, Natural killer cells, T-cells, and Dendritic cells. It promotes the cellular TH1 immune response over the antibody responses which may be overactive in autoimmune diseases.  LL-37 balances the inflammatory immune response to clear the body of infection with the anti-inflammatory promotion of healing. The inflammatory response is needed to get rid or protect against infection but these responses can prevent adequate or complete healing resulting in scar formation and autoimmune diseases if left unregulated.  LL-37 balances inflammation with healing at least through mechanisms studied from macrophages.

Thus, LL-37 plays a role in wound healing with reduction in tissue inflammation. It recruits mesenteric stem cells which rebuild tissue. It also promotes the of making new blood vessels especially to the injured areas. This is called angiogenesis. Finally, LL-37 interacts with skin protein and the precursors  keratinocytes and fibroblasts that allow for wound closure and new skin.

Ongoing research into LL-37’s abilities to cause cancer cells to die has been seen in colon and gastric cancers. Other cancers such as lung, ovarian, and breast show other effects that are still under investigation.



LL-37 is therefore an important peptide for the treatment of gut, mucous and skin infections, immune balance to minimize the risk of initiating or promoting autoimmunity, and allow for better wound healing minimizing the risk of scar formation and allowing for more complete healing.

If you would like to learn more about LL-57,  other AFH Peptide therapies or AFH  anti-aging and regenerative medicine programs, contact us at info@jeffreymarkmd.com, find us on the web at www.allfunctionalhealth.com, or call (25) 736-9828. . We’ve helped thousands of people on their journey of health and we look forward to helping you as well. So take care and stay healthy.

Jeffrey Mark, M.D.

Helping clients with compassionate and comprehensive medical care for over 25 years with 4 board certifications in functional medicine, gastroenterology, internal medicine, and anti-aging/ regenerative medicine . IFMCP, ABIM Gastroenterology, NPAS Internal Medicine, ABAARM.