Oxidative stress results from an increased production of reactive oxygen (or nitrogen) species (ROS and RNS) or a decrease in the capability of the antioxidative defence system of the body and causes damage to various molecules and cell structures. Alterations in the function of different molecules and signalling pathways due to oxidative damage consequently cause a variety of diseases. Recent data suggests a significant interconnection between changes induced by oxidative stress and the immune response. Furthermore, prolonged inflammation and disturbance in immune homeostasis can lead to more pronounced oxidative stress and more severe damage of cellular and tissue structures.

Autoimmune disorders encompass a heterogeneous spectrum of conditions characterised by aberrant immune responses in which the immune system responds to self-antigens due to dysregulation of adaptive immunity and increased production of autoantibodies. Autoimmune disorders are also characterised by increased the production of ROS and RNS. On the other hand, some immunosuppressive drugs commonly used in the treatment of some autoimmune diseases may increase production of ROS and oxidative stress. Given the complex interconnection between the immune system and oxidative stress, there is a need for experimental and clinical results exploring the causal relationships between oxidative stress and autoimmunity on molecular, cellular, systemic, and clinical levels. The heterogeneity of autoimmune disorders and the diverse immune components involved may lead to a corresponding level of variety in the changes in oxidative stress and the antioxidative system. Closer insight into the detrimental effects of oxidative stress in autoimmune disorders could provide a better understanding of pathophysiological changes and clinical expression and lead to more specific therapeutic approaches, as well as help shed light on new directions for future research. Antioxidants with various mechanisms of action could show different therapeutic potential in autoimmune disorders and different immunomodulatory potential.

The aim of this Special Issue is to encourage authors to submit original scientific papers and review articles which contain novel information concerning the roles of oxidative stress in the physiological regulation of immune responses, molecular mechanisms connecting autoimmune diseases and oxidative stress, the effects of immunomodulatory therapy on oxidative stress in autoimmune diseases, as well as the use of antioxidants in therapy for autoimmune conditions.

Potential topics include but are not limited to the following:

• Oxidative stress in immune regulation
• Role of redox balance in the orchestration of immune reactivity
• Molecular basis of oxidative damage in autoimmunity
• Signalling pathways and oxidative stress in autoimmune conditions
• Cellular damage induced by oxidative stress in autoimmune diseases
• Oxidative stress and mitochondrial dysfunction in autoimmunity
• Immunomodulatory therapy and oxidative stress
• Effects of antioxidants on the immune response in autoimmune disorders
• Alterations of the antioxidant defence system in autoimmunity
• Clinical use of antioxidants in therapy for autoimmune diseases