Changes in JC virus-specific T cell responses during natalizumab treatment and in natalizumab-associated progressive multifocal leukoencephalopathy. oleh Molly R Perkins, Caroline Ryschkewitsch, Julia C Liebner, Maria Chiara G Monaco, Danielle Himelfarb, Sara Ireland, Annelys Roque, Heather L Edward, Peter N Jensen, Gina Remington, Thomas Abraham, Jaspreet Abraham, Benjamin Greenberg, Charles Kaufman, Chris LaGanke, Nancy L Monson, Xiaoning Xu, Elliot Frohman, Eugene O Major, Daniel C Douek