Volume 12 Issue 4, April 2016

Mitochondria are the powerhouses of the cell, providing energy through oxidative respiration. Possibly owing to their similarities with bacteria, however, mitochondria extruded from cells promote inflammation. New research demonstrates that in systemic lupus erythematosus, mitochondrial respiration is critical in neutrophil extracellular trap formation, and that mitochondria released by neutrophils induce inflammatory cytokine production.

Medical management of women with rheumatic diseases during pregnancy is challenging owing to incomplete information regarding medication safety. The British Society for Rheumatology and the British Health Professionals in Rheumatology committee published consensus guidelines that provide a good first step towards narrowing the knowledge gap in this important field.

The selective utilization of IRAK kinases, which are thought to be recruited to MyD88 to form the 'Myddosome', has been shown to differ substantially in mouse and human cells. This finding has important implications for the development of therapeutics for inflammatory and autoimmune disorders associated with Toll-like receptors.

The immunomodulatory properties of vitamin D suggest it plays a central part in inflammatory diseases such as rheumatoid arthritis, a link that has been reinforced by findings from epidemiological andin vitro studies. In this Review, Jeffery et al. provide an overview of the known effects of vitamin D in the immune system and discuss how manipulation of the vitamin D pathway might be used for therapeutic purposes.

Several microRNAs (miRNAs) that are involved in the regulation of cellular metabolism or immune processes are deregulated in patients with rheumatic diseases, such as rheumatoid arthritis or osteoarthritis. These small inhibitory molecules offer considerable potential for the treatment of these disorders, but a multidisciplinary approach is needed to limit their potential adverse effects through, for example, improved specificity and delivery.

This Review discusses the progress made by international networks in the USA, Europe and Asia towards improving the efficacy of existing and novel therapies for lupus nephritis. Strategies being actively pursued include biomarker identification and optimization of induction and maintenance treatment. These approaches aim to improve patients' outcomes by raising complete response rates, reducing renal flares, preserving long-term renal function, and minimizing treatment-related toxic effects.

Although a generally safe and effective drug that is widely used in the treatment of gout, allopurinol can in rare instances be associated with severe adverse events. The presentation, risk factors and mechanisms of allopurinol-induced hypersensitivity are the focus of this Review, as well as strategies to avoid or minimize such reactions.

Extracellular vesicles (EVs) are a heterogeneous group of membrane-enclosed particles involved in a multitude of biological processes, including the development and homeostasis of cartilage tissue. In this Perspectives article, the authors describe the current knowledge of the functions of EVs in joint physiology and explore the therapeutic potential of EVs as tools to deliver biologically-active therapeutic agents to joints.