Year: 2026
Type: review
Study design: Systematic Review
Abstract: Cathelicidin LL-37 is a multifunctional antimicrobial peptide central to innate immunity. Its dysregulated expression in leprosy patients and household contacts suggests a significant role in pathogenesis and potential as a prognostic biomarker. This systematic review followed PRISMA guidelines, searching PubMed, Cochrane Library, and Google Scholar for studies published between 2010–2025. Inclusion criteria focused on human observational research assessing LL-37 at protein or gene levels in serum, skin, or blood. From 55,212 records, four studies were analyzed. Matzner et al. (2010) identified significantly lower serum LL-37 in untreated leprosy patients. Conversely, Argentina et al. (2023a, 2023b) reported elevated LL-37 protein and CAMP gene expression in skin lesions, with intermediate levels found in household contacts. Oliveira et al. (2022) observed reduced CAMP and vitamin D receptor expression in peripheral blood across both patients and contacts, correlating with inflammatory cytokine profiles that persisted post-therapy. The evidence reveals a compartmentalized paradox: systemic suppression of LL-37 alongside localized overexpression in lesional skin. Systemic downregulation may be linked to impaired vitamin D–CAMP pathways, while local upregulation reflects innate activation against bacillary load. Intermediate levels in contacts suggest immunological priming from exposure. The vitamin D–cathelicidin axis emerges as a potential therapeutic target and a valuable biomarker for disease activity and risk stratification in endemic regions.
Source: Journal of chemical health risks
Author: Nur Hasira Mustakim
Institution: Hasanuddin University
Language: English
Subfield: Infectious Diseases
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7217611391