title: Anti-JC virus antibody testing for natalizumab-induced progressive multifocal leukoencephalopathy: Where are we and where should we go?
authors.affiliation: Ruhr-University, Germany Andrew.Chan@rub.de.
authors.forename: Andrew
authors.initials: A
authors.lastname: Chan
authors.affiliation: Ruhr-University, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Gold