1. Biophysics Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA; St Jude Children's Research Hospital, Memphis, Tennessee, USA.
2. Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, Wisconsin, USA; St Jude Children's Research Hospital, Memphis, Tennessee, USA.
3. Department of Biomedical and Engineering, University of Wisconsin-Madison, Madison, Wisconsin, USA; and St Jude Children's Research Hospital, Memphis, Tennessee, USA.
4. Department of Hematology, St Jude Children's Research Hospital, Memphis, Tennessee, USA.