MAPT and Huntington disease: Indeed, we observed that all three HD transplanted cases exhibited various degrees of tau pathology in different structures of the cerebral tissue (i.e. cortex and striatum), as previously reported (Cisbani et al., 2017; Vuono et al., 2015; Fernández-Nogales et al., 2014; Gratuze et al., 2016; Salem and Cicchetti, 2023).