Inhibitory phenotype of HBV-specific CD4+ T-cells is characterized by high PD-1 expression but absent coregulation of multiple inhibitory molecules. oleh Bijan Raziorrouh, Malte Heeg, Peter Kurktschiev, Winfried Schraut, Reinhart Zachoval, Clemens Wendtner, Martin Wächtler, Michael Spannagl, Gerald Denk, Axel Ulsenheimer, Bertram Bengsch, Hanspeter Pircher, Helmut M Diepolder, Norbert H Grüner, Maria-Christina Jung