PDCD1 and leprosy: Collectively, the blocking of IL-10R results suggesting that IL-10 producing Bregs facilitates leprosy pathogenesis by inducing the expression of FoxP3 and inhibitory molecule PD-1 and function of T-regulatory cells and, also by converting the effector T cells into Tregs which play important role in immunosuppression of the host immune system toward M. leprae thus aiding in the pathogenesis of leprosy.