Low serum levels of cathelicidin LL-37 in leprosy.

The antimicrobial peptide cathelicidin LL-37 possesses antituberculous activity, its association with other mycobacterial diseases, such as leprosy, is unknown. We studied serum cathelicidin and 25OH-vitamin D3 levels in 29 leprosy patients and 19 healthy individuals from Yemen. Cathelicidin levels were significantly lower in both treated (n=15) and untreated leprosy patients (n=14) when compared to controls (P<0.001). Within leprosy patients, levels were lower in those who very recently developed disease (untreated group) when compared to already treated patients (P<0.05). 25OH-vitamin D3 levels were not different between groups. The results suggest a potential association of cathelicidin LL-37 with Mycobacterium leprae infection.