LL-37, also known as Cathelicidin, is an antimicrobial peptide that plays a crucial role in the innate immune system of humans and other mammals. It is derived from the cleavage of a larger precursor protein, hCAP18 (human Cathelicidin antimicrobial protein 18). LL-37 is unique among antimicrobial peptides due to its broad spectrum of activity against bacteria, viruses, and fungi, and its ability to modulate immune responses.
Found in various human tissues and immune cells, including neutrophils, epithelial cells, and keratinocytes, LL-37 acts as a first line of defense against invading pathogens. Beyond its direct antimicrobial properties, it is involved in important biological processes such as wound healing, inflammation modulation, and angiogenesis (the formation of new blood vessels). Its multifaceted nature makes it a subject of extensive research in various medical fields. (PubChem, NIH ODS)
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Known interactions
Category rule: peptide × hormone
Note
Injectable peptides plus hormones can have overlapping or compounding effects that aren't always well characterized.
Track bloodwork with a provider; don't assume combinations are neutral.
Frequently asked
Sources referenced
["PubChem","NIH Office of Dietary Supplements (ODS)","MedlinePlus","Mayo Clinic","Examine.com","DrugBank","Cochrane Library","U.S. Food and Drug Administration (FDA)"]
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