Acknowledgements
We thank the families of patients whose generosity made this research possible. Manuela Neumann provided the anti-phosphorylated TDP-43 antibody. We thank our colleagues at the CNDR, Perelman School of Medicine at the University of Pennsylvania, for technical support and advice, particularly Theresa Schuck. This work was supported by grants from the National Institutes of Health.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.