Exploring the molecular landscape of pediatric idiopathic nephrotic syndrome-associated glomerular damage andproteinuria. - Finanziato dall’Unione europea – Next Generation EU

Idiopathic nephrotic syndrome (INS) is a kidney disease, characterized by proteinuria and tissue edema, with the needfor intense and long-lasting immune suppression and, in a minority of children, kidney replacement therapy. One-thirdof the cases with the worst prognosis have a genetic cause (monogenic) of the disease. In the non-genetic cases, lymphocyte dysregulation has been strongly advocated in the pathogenesis, but a clearunderstanding of the relation between immune unbalance and proteinuria development is still lacking. Moreover,despite both genetic risks and environmental modifi cations probably co-participate in INS susceptibility, nowadays itsclassifi cation is mainly based on clinical and biochemical features. Our project will investigate the INSpathophysiology, by approaching the disease from the genetic, molecular, and clinical sides, looking forward to noveldiagnostic tools and therapeutic options. The project will engender a “genetic grouping” of immune-related INS patients based on an immune gene signature.The genetic categorization will be combined with the characterization of the molecular content of serum extracellularvesicles (EVs), which will exploit the role of non-invasive biomarkers, in tracing the kidney damage progression inimmune-related INS children. Furthermore, the molecular mechanisms behind the glomerular damage and proteinuriawill be deeply investigated, using a millifl uidic three-layer co-culture model mimicking the glomerulus. Patient-derivedsera will be administrated to the three-layer glomerular co-cultures to determine the effects of soluble factor/s ondifferent kidney cells. The multiple cell interactions, taking place in the millifl uidic glomerular system, will be helpful todeeply investigate the development of proteinuria and acute glomerular damage. Finally, chronic exposure ofpodocytes, the most important cells of the glomeruli, to INS serum and respective EVs, will defi ne epithelial-mesenchymal transition (EMT) events, possibly involved in the onset of podocyte dysfunction and glomerulosclerosis.The hitherto uninvestigated role of RNA binding proteins, key players in alternatively spliced transcripts generation andEMT, will be studied. In summary, we aim to identify the molecular mechanisms behind the pathogenesis of immune-related INS that will setthe basis for new “personalized” pharmacological intervention in this disease.