Introduction
nephrotoxicity, INS, infections, steroid-sensitive, cancer, lymphoproliferative disorders, myelotoxicity
INS, IDIOPATHIC NEPHROTIC SYNDROME, KIDNEY FAILURE, INFECTIONS
Idiopathic nephrotic syndrome (INS) is the most frequent form of NS of childhood, affecting 1.4–6.1 per 100,000 children (From a clinical standpoint, INS is very heterogeneous. Although steroid-sensitive forms never lead to kidney failure, 30% of patients experience a frequently relapsing or steroid-dependent evolution, which requires prolonged glucocorticoid use and the introduction of glucocorticoid-sparing immunosuppressive agents, such as calcineurin inhibitors, alkylating agents, and/or mycophenolate mofetil and rituximab. These immunosuppressive regimes are burdened by poor tolerability and substantial morbidity, including nephrotoxicity, myelotoxicity, and increased risk of cancer, lymphoproliferative disorders, and serious infections (In this context, treatment with mesenchymal stromal cells (MSCs) could be a valuable therapeutic option to prevent relapses and spare glucocorticoid and immunosuppressive therapy. MSCs are multipotent progenitor cells resident in the bone marrow (BM) and other tissues (It has been debated whether autologous patient-derived MSCs maintain the full spectrum of regenerative and immunomodulatory properties of MSCs obtained by third-party healthy donors (reviewed in ref. Based on these encouraging preclinical results, we designed an open-label phase I study to primarily explore the safety and feasibility of autologous BM-MSC treatment in children and young adults with severe steroid-dependent, multi-relapsing forms of INS.