Ariga, S. K. | bioRxiv Science

bioRxiv2023

Identification of Spinster Homolog 3 as a novel putative LL-37 receptor

BackgroundAntimicrobial Peptides are primitive components of the innate immune response. LL-37, a human antimicrobial peptide, has been researched for its therapeutic potential in immune-inflammatory diseases. This study aimed to identify novel LL-37 receptors. Methods and ResultsUsing the phage display technique, the sequence GNWSFV was selected and found to bind to LL-37. BLAST analysis revealed that this sequence has a high degree of similarity to a portion of human transmembrane protein Spinster Homolog 3. ConclusionOur study suggests that Spinster Homolog 3 may be a potential therapeutic target for LL-37-related diseases.

immunology↗

bioRxiv2023

Cathelicidin downregulates neurotensin and substance P hippocampal levels

BackgroundSepsis is a life-threatening condition and septic encephalopathy is an early and frequent manifestation of this disease. Antimicrobial peptides are important components of innate immunity playing a crucial role during bacterial infections. Here, we investigate the protein levels of several neuropeptides in CRAMP-deficient and wild-type mice, in healthy conditions and following experimental sepsis. MethodsMice were submitted to cecal ligation and puncture and the protein levels of neurotensin, substance P, oxytocin and {beta}-endorphin were evaluated in the brain. ResultsWe found that CRAMP-deficient mice produce significantly less neurotensin and substance P than wild-type mice in the hippocampus, both before and 24 hours following experimental sepsis, but not 15 days post-septic shock. ConclusionsThe hippocampus is a complex structure, highly vulnerable during sepsis. The role of antimicrobial peptides and their interplay with neuropeptides should be further evaluated in this scenario.

immunology↗