Haemopoietic progenitor homing and mobilization.

Despite the widespread clinical exploitation of HPC mobilization and homing, the mechanisms central to these two phenomena are still unknown. However, the evolving concepts of multi-step adhesion cascades and demonstration of intracellular signalling which links lectin/carbohydrate binding with integrin activation in HPCs and other leucocytes suggests that HPC homing may be analogous to leucocyte homing in other systems. The complexity of this system is apparent from the data presented above, and more sensitive methods need to be developed to dissect the various adhesion pathways which may be involved.