PML and early-onset autosomal dominant Alzheimer disease: Two independent VP1 antibodies, when used at higher concentrations on such sections, in addition revealed dispersed viral immunoreactivity within areas of active infection, but no staining in adjacent tissue without PML pathology, nor in control (non-diseased), Alzheimer’s disease, or multiple sclerosis brain tissues (Fig 5C, S1 Fig, and not shown).