CD69 and B-cell chronic lymphocytic leukemia: NK cells are key innate immune effectors known to be important for the efficacy of rituximab- and lenalidomide-based immunotherapy for CLL.8, 28 To investigate the role of NK cells, PBMCs from healthy donors and patient samples were incubated with reovirus and NK cell (CD3−CD56+) activation was determined by CD69 and CD107a/b surface expression (Figures 2b and c, respectively).