Paraneoplastic cerebellar degeneration: Yo antibody alters mitochondrial calcium buffering capacity

Abstract Aim: Neurodegeneration is associated with dysfunction of calcium buffering capacity and thereby sustained cellular and mitochondrial calcium overload. Paraneoplastic cerebellar degeneration (PCD), characterized by progressive Purkinje neurone degeneration following paraneoplastic Yo antibody internalization and binding to cerebellar degeneration‐related protein CDR2 and CDR2L, has been linked to intracellular calcium homeostasis imbalance due to calbindin D28k malfunction. Therefore, we hypothesized that Yo antibody internalization affects not only calbindin calcium binding capacity, but also calcium‐sensitive mitochondrial‐associated signalling, causing mitochondrial calcium overload and