Induction of Cytokine Storm with Organ Dysfunction and Ineffective Response to Tocilizumab and Steroids by CAR-T Cell Therapy is Rescued by Mesenchymal Stem Cells: A Case Report

Two of the main toxicities linked with chimeric antigen receptor T (CAR-T) cell therapy are cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS). It is believed that an inflammatory factor storm resulting in organ dysfunction is the fundamental pathophysiology, and this has a significant impact on the survival rate following CAR-T cell therapy. While steroids and other IL-6R antagonists like Tocilizumab are useful treatment approaches, not all patients benefit from them. Following CD19-targeted CAR-T cell infusion, a 3-year-old kid with relapsed refractory B-cell acute lymphoblastic leukemia (ALL) started to have CRS on Day 1. Despite receiving steroids and tocilizumab early on, his illness worsened and eventually led to multiple organ failure, particularly heart failure. After receiving mesenchymal stem cells (MSCs) as a rescue treatment on Days 17 and 20, the patient's clinical symptoms were stabilized by Day 25. Negative microscopic residual disease (MRD) was achieved with CAR-T therapy, and CAR expression was maintained in peripheral blood until Day 75. The case implies that MSC may be a useful treatment for multi-organ dysfunction that results from severe CRS and ICANS brought on by CAR-T cell therapy.