Enigmas of primary immunodeficiency and mycobacterial infection in our territory

Abstract

Defects of the immune system in Primary immunodeficient diseases (PIDs) predispose individuals to recurrent infections. Complex genetic components for susceptibility to mycobacterial disease have been suggested. Natural human immunity to the mycobacteria group, including Mycobacterium tuberculosis(MTB), Bacille Calmette-Guerin (BCG) or nontuberculous mycobacteria (NTM) relies on the functional IL-12/23-IFN-γ integrity of macrophages (monocyte/dendritic cell) connecting to T lymphocyte/NK cells [1]. Restricted defective molecules in the circuit and recently discovered CYBB responsible for autophagocytic vacuole and proteolysis have been identified in around 60% of patients with the Mendelian susceptibility to the mycobacterial disease (MSMD) phenotype [2]. Primary defects in oxidase activity in chronic granulomatous disease (CGD) lead to severe, life-threatening infections. The role of phagocytic respiratory burst in host defense against mycobacterium tuberculosis was controversial. Previous studied showed that the critical role at reactive oxidants is to serve as intracellular signals for activation of microbicidal enzymes, rather than excretions a microbicidal effect perse [3]. The role of phagocytic respiratory burst in host defense against M. TB is further supported by recent studies discovered immunological defects secondarily affecting phagocyte respiratory burst function and resulting in primary immunodeficiencies with varied phenotypes, including susceptibilities to pyogenic or mycobacterial infections [4]. The patients with severe PID’s like SCID have broader diverse infections susceptibility and mycobacterial infections as well, however, Common variable immunodeficiency (CVID) mostly characterized by a deficiency of immunoglobulins and recurrent sinopulmonary infections.