CD19 and non-Hodgkin lymphoma: CD19 (B4) has a wider expression profile than CD20 on both normal B-cells and NHL cells (Nadler et al, 1983; Uckun et al, 1988), and could be a more suitable ADC target as various anti-CD19 antibodies have been shown to internalize at different rates in several studies (Uckun et al, 1988; Press et al, 1989, 1994; Pulczynski et al, 1993; van Oosterhout et al, 1994; Sapra & Allen, 2002).