Salivary Cathelicidin (LL-37) in Children and Adolescents Living with HIV.

Introduction: Human cathelicidin LL-37 is a salivary antimicrobial peptide (AMP) with broad-spectrum activity against oral diseases, but few studies have assessed its role in children and adolescents living with HIV (CALHIV). We assessed salivary LL-37 levels and correlates in a long-term cohort of Kenyan CALHIV followed since antiretroviral therapy (ART) initiation.

Methods: Saliva was collected from 76 CALHIV who were recruited from two ongoing pediatric HIV studies in Nairobi, Kenya. Oral examinations documenting oral manifestations of HIV, dental caries, and gingivitis were completed. Additional variables included age, sex, HIV treatment (initial ART regimen) and disease parameters, caregivers' demographics, and oral pathologies were conducted. Data were statistically analyzed using the independent T test on the log-transformed LL-37.

Results: At the oral exam visit, the mean age of participants was 13.3 years (±SD = 3.4), and the median CD4 count was 954 cells/mm³. Mean salivary cathelicidin values of the cohort were 23.7 ± 21.1 ng/mL. Children with permanent dentition at time of oral examination, and children who initiated ART at ≥2 years old had higher mean LL-37 concentrations compared to those with mixed dentition and those who initiated ART <2 years old (p = 0.0042, 0.0373, respectively). LL-37 levels were not found to differ by initial type of ART regimen, CD4 count, or oral disease.

Conclusion: Further research and longitudinal studies are necessary to evaluate and improve the innate immunity of CALHIV in Kenya.