Vitamin D is a fat-soluble secosteroid that exists in two forms: vitamin D₂ and vitamin D₃

The major evolutionary advance represented in the human immune system is a mechanism of antigen-directed immunity in which tumor necrosis factor (TNF)-α and TNF receptors (TNFRs) play essential roles. Binding of TNF-α to the 55-kDa type I TNFR (TNFR1, TNFRSF1A, CD120a, p55) or the 75-kDa type II TNFR (TNFR2, TNFRSF1B, CD120b, p75) activates signaling pathways controlling inflammatory, immune and stress responses, as well as host defense and apoptosis. Multiple studies have investigated the role of TNFRs in the development of early and late renal failure (diabetic nephropathy, nephroangiosclerosis, acute kidney transplant rejection, renal cell carcinoma, glomerulonephritis, sepsis and obstructive renal injury). This article reviews the general characteristics, the analytical aspects and the biology of TNFRs in this domain. In addition, the potential therapeutic application of specific TNFR blockers is discussed.

Initially considered as a macrophage inhibitor (macrophage inhibitory cytokine-1), growth differentiation factor 15 (GDF-15) has been identified as a pleiotropic protein that plays key roles in prenatal development, in inflammation, in the regulation of cellular responses to stress signals, and in tissue repair after acute injuries in adult life. Multiple studies have revealed that GDF-15, a distant member of the transforming growth factor β (TGF-β) family, acts as a critical hormone to regulate lipid and carbohydrate metabolism. Besides its role in the tumorigenesis and diagnosis of cancer, serum GDF-15 concentrations reflect a “systemic response” and are predictive of all-cause mortality. Based on the knowledge from animal studies of its involvement in multiple inflammatory processes, we will focus in this review on the current clinical data on GDF-15 as a biomarker for cardiovascular disease, kidney disease, liver disease, the metabolic syndrome, diabetes mellitus and sepsis.

Acute generalized exanthematous pustulosis (AGEP) is a significant adverse cutaneous reaction, most often provoked by drugs and acute infections. The recognition of AGEP is important, in order to avoid confusion with a systemic infection and consequently to avoid incorrect treatment. The clinical hallmark is the presence of multiple disseminated sterile pustules on an erythematous background, associated with fever and a massive neutrophilia and sometimes eosinophilia. The disease is characterised by an acute onset and a spontaneous resolution within 2 weeks. The involvement of drug-specific T cells in the pathomechanism can be confirmed by positive skin patch tests and lymphocyte transformation tests. In this review, we highlight the main clinical, pathophysiological and diagnostic aspects of this peculiar form of drug allergy.

Inflammation is a key player in the development of an increasing amount of diseases. The soluble urokinase plasminogen activator receptor (suPAR) is a highly flexible molecule with intrinsic chemotactic properties. This glycoprotein has been evaluated as a biomarker of inflammation, immune activation, organ damage and clinical outcome in several pathologies, including cardiovascular disease, hepatitis, renal disorders and rheumatic pathologies. The use of this early warning inflammatory biomarker could potentially improve the prediction of the severity of these diseases and mortality. In the present paper, we describe the general characteristics of suPAR and its intriguing role as a biomarker in different inflammatory diseases.