[Clinical and molecular inflammatory alterations in chronic granulomatous disease]

Chronic granulomatous disease (CGD) is an inborn error of immunity. CGD is characterized by a deficiency in the function of the NADPH oxidase complex. CGD has been an opportunity to study the function of reactive oxygen species (ROS) in the innate immune system. The absence of ROS produced by NADPH oxidase in neutrophils and macrophages leads to an increased susceptibility to bacterial and fungal infections since ROS participate in the elimination of microorganisms. Inflammatory and autoimmune manifestations are also present in CGD; however, the causal connection between the lack of ROS and inflammatory symptoms is not entirely clear. Different in vitro assays have been conducted in humans and clinical trials have been conducted in mice in order to try to understand this relationship. Studies show that ROS react with different molecules of the immune system, either by inhibiting or by stimulating their function, which explains why various inflammation pathways that are not related to each other are affected in CGD; therefore, the described mechanisms of affectation have been diverse, such as a greater production of proinflammatory cytokines, an increase in TH17 lymphocytes, and an alteration in processes like spherocytosis, apoptosis, autophagy, and inflammosome. Understanding the mechanisms that lead to inflammation in the deficiency of the NADPH oxidase complex has led to the proposal of new treatments that act on processes like autophagy, inflammosome, or blocking proinflammatory cytokines. In this review, we describe the different inflammatory manifestations in CGD and the molecular mechanisms through which the lack of ROS leads to hyperinflammation.