Soluble mediators of immune significance in sera of leprosy patients

Background: The disease leprosy is categorized by a wide spectrum of clinical forms imposed by the patient's immune responses to the organism, Mycobacterium leprae. Soluble receptors and soluble mediators are important for regulation of immune responses. Objectives: As leprosy reactions are known immune inflammatory reactions during the disease process, the aim of the study was to screen nitrite, IL-6 cytokine and sTLR2 in sera samples to identify circulating biomarkers associated with leprosy and T1R and T2R among patients recruited from the Northern part of India. Methods: Leprosy patients recruited in our Institute were included in this study. We analysed the level of nitrite, soluble TLR2 and IL-6 in sera of leprosy patients, healthy controls and healthy household contacts by colorimetric assay and ELISA respectively. Results: The level of serum nitrite was observed to be higher in tuberculoid leprosy patients compared to lepromatous leprosy patients (p = 0.006). The level was also higher in healthy contacts of leprosy patients compared to lepromatous leprosy patients (p = 0.008). The sTLR2 level was significantly higher in healthy controls than leprosy patients (p = 0.002) and their healthy contacts (p = 0.001). The level of IL-6 in serum was significantly higher in leprosy patients than in healthy controls (p = 0.001). Conclusion: Nitrite, IL-6 cytokine and sTLR2 are shown to be potential circulating biomarkers associated with leprosy among patients recruited in Northern India. Keywords: Leprosy, reactions, M. leprae, soluble toll like receptor 2, nitric oxides