Recommendations for the use of COVID-19 vaccines in patients with immune-mediated kidney diseases.

Coronavirus Disease 19 (COVID-19) vaccine platforms are becoming available and are the most promising strategy to curb the spread of SARS-CoV-2 infections. However, numerous uncertainties exist regarding the pros and cons of vaccination, especially in patients with (immune-mediated) kidney diseases on immunosuppressive drugs. Here, members of the Immunonephrology Working Group (IWG) of the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) discuss thirteen frequently-asked questions regarding safety and efficacy of the most promising vaccine candidates. Post-marketing surveillance should be performed to estimate the rate of vaccine response (humoral and cellular) of different vaccine platforms, and surveillance of disease activity following administration of COVID-19 vaccines. Some of the candidates induce signaling pathways which also promote autoimmune kidney diseases, e.g. type I interferons in systemic lupus erythematosus. Efficacy estimates would thus far favor the use of selected COVID-19 vaccines, such as BNT162b2, mRNA-1273 or Gam-COVID-Vac. Humoral immune response after vaccination should be monitored using appropriate assays. Even in the absence of neutralizing antibodies patients might be protected by a sufficient cellular immune response capable to reduce severity of COVID-19. A reduced vaccine response after the use of CD20-depleting agents is anticipated, and it is particularly important to discuss strategies to improve vaccine response with these patients. Distancing and shielding measures remain important as not all vaccines fully protect from coronavirus infection. In-depth information about the most pressing vaccine questions is essential to reduce vaccine hesitancy of patients.

Recommendations for the management of patients with immune-mediated kidney disease during the severe acute respiratory syndrome coronavirus 2 pandemic.

The coronavirus disease 2019 (COVID-19) pandemic has created major challenges for all countries around the globe. Retrospective studies have identified hypertension, cardiovascular disease, diabetes and older age as risk factors for high morbidity and mortality from COVID-19. There is a general concern that patients with immune-mediated kidney diseases, namely those on immunosuppressive therapies and/or those with more advanced kidney failure, could particularly be at risk for adverse outcomes due to a compromised antiviral immunity. Uncertainties exist on how management routines should be reorganized to minimize the risk of severe acute respiratory syndrome coronavirus 2 infection and what measures are necessary for infected patients. The aim of the present review of the Immunonephrology Working Group of the European Renal Association-European Dialysis and Transplant Association is to provide recommendations for the management of patients with immune-mediated kidney diseases based on the available evidence, similar circumstances with other infectious organisms and expert opinions from across Europe. Such recommendations may help to minimize the risk of encountering COVID-19 or developing complications during COVID-19 in patients with immune-mediated kidney disease.

Epigenetic Modulation of Gremlin-1/NOTCH Pathway in Experimental Crescentic Immune-Mediated Glomerulonephritis.

Crescentic glomerulonephritis is a devastating autoimmune disease that without early and properly treatment may rapidly progress to end-stage renal disease and death. Current immunosuppressive treatment provides limited efficacy and an important burden of adverse events. Epigenetic drugs are a source of novel therapeutic tools. Among them, bromodomain and extraterminal domain (BET) inhibitors (iBETs) block the interaction between bromodomains and acetylated proteins, including histones and transcription factors. iBETs have demonstrated protective effects on malignancy, inflammatory disorders and experimental kidney disease. Recently, Gremlin-1 was proposed as a urinary biomarker of disease progression in human anti-neutrophil cytoplasmic antibody (ANCA)-associated crescentic glomerulonephritis. We have now evaluated whether iBETs could regulate Gremlin-1 in experimental anti-glomerular basement membrane nephritis induced by nephrotoxic serum (NTS) in mice, a model resembling human crescentic glomerulonephritis. In NTS-injected mice, the iBET JQ1 inhibited renal Gremlin-1 overexpression and diminished glomerular damage, restoring podocyte numbers. Chromatin immunoprecipitation assay demonstrated BRD4 enrichment of the Grem-1 gene promoter in injured kidneys, consistent with Gremlin-1 epigenetic regulation. Moreover, JQ1 blocked BRD4 binding and inhibited Grem-1 gene transcription. The beneficial effect of iBETs was also mediated by modulation of NOTCH pathway. JQ1 inhibited the gene expression of the NOTCH effectors Hes-1 and Hey-1 in NTS-injured kidneys. Our results further support the role for epigenetic drugs, such as iBETs, in the treatment of rapidly progressive crescentic glomerulonephritis.