Figure 6.

Effects of interdomain hinge flexibility on lifetimes of doublets of neutrophils or microspheres in a flow field. Neutrophils or mixtures of neutrophils with microspheres bearing L-selectin or L-selectinN138G were perfused through a flow chamber coated with HSA. Representative images of randomly colliding cells and/or microspheres were collected at 250 frames/s. A doublet formed by collision of two neutrophils (A) or of a neutrophil and an L-selectin microsphere (B), each dissociated within 0.028 s. In contrast, a doublet formed by the collision of a neutrophil and an L-selectinN138G microsphere (C) persisted for at least 0.1 s, until it flowed out of the field of view.