The immune response of macrophages to Mycobacterium leprae infection via Naip5, a member of Nod-like receptor protein (135.75)

Abstract

Abstract Naip5 is a member of the NOD-like receptors (NLRs) involved in the cytosolic recognition of pathogen-associated molecular patterns. Recently, A/J mice have been found to have amino acid differences in the Naip5, one of the adaptor proteins for caspase-1 activation, and this defect is associated with a susceptibility to Legionella infection suggesting an important role of Naip5 in the immune response to intracellular pathogens, such as M. tuberculosis and M. leprae. In this study, the immune responses of macrophages from A/J mice against M. leprae infection were studied and compared to those of macrophages from C57BL/6 (B6) mice. A/J and B6 macrophages induced high levels of NF-¥ê B activation when infected with M.leprae. Caspase-1 activation and IL-1beta secretion were also induced in both macrophages. However, macrophages from A/J mice have impaired caspase-1 activation, IL-1beta expression, and nitric oxide (NO) production, partially, compared to macrophages from B6 mice. These results suggest that NOD family proteins may have a role in the innate immune response to M. leprae.