The slow rolling motion of white blood cells transiently adhering to the interior surface of venules under shear is simulated numerically. Molecular bond breakage events cause a noisiness in rolling velocity over time scales longer than the lifetime of an individual bond. It is shown that the hydrodynamic interactions between particles produce a smoother rolling behavior, by modulating the cell's motion during the brief forward jumps following a bond breakage event. Good agreement is found with flow chamber experiments using adhesive spherical beads.