A Study of NLRC4 in Patients with Leprosy.

BACKGROUND: Activation of the NLRC4 inflammasome appears to start many signalling processes inside the host, including caspase-1, the principal protease responsible for converting proIL-1β and IL-18 to active, secreted IL-1β and IL-18, resulting in pyroptosis.

AIMS: To evaluate NLRC4 level in patient's blood serum to highlight its role in the pathogenesis of leprosy.

MATERIALS AND METHODS: This prospective study was conducted on 40 patients with leprosy and 30 healthy individuals of matched ages and sexes. All patients were subjected to complete history taking, general and dermatological examination, laboratory investigations, slit skin smear with bacillary index, and clinical classification of the studied leprosy group patients regarding disability according to disability grading. And finally, measurement of serum NLRC4 level by ELISA.

RESULTS: In the paucibacillary (PB) group, NLRC4 serum level ranged from 0.9 to 1.8 ng/ml with 1.43 ± 0.28 ng/ml, while in the multibacillary (MB) group, it ranged from 1.2 to 5.7 ng/ml with 2.83 ± 1.11 ng/ml. NLRC4 serum level had increased significantly in MB patients compared to PB patients ( P < 0.05). There was a significant difference among the three studied groups, regarding the serum level of NLRC4 ( P < 0.05). In leprosy patients, significant positive correlations were found between serum levels of NLRC4 and bacillary index and duration of leprosy.

CONCLUSIONS: Leprosy patients had considerably greater serum levels of NLRC4 than controls. It was much greater in MB patients than in PB patients.