BONE-MARROW-DERIVED MURINE MAST-CELLS MIGRATE, BUT DO NOT DEGRANULATE, IN RESPONSE TO CHEMOKINES

We have determined that several chemokines induce mast cell migration in vitro. This directed migration is dependent on the presence of part icular extracellular matrix proteins and the activation status of the cells. Mast cell haptotactic responses were observed in response to va rious chemokines on vitronectin-, laminin-, and fibronectin-coated fil ters. Unstimulated mast cells were chemoattracted only by monocyte che motactic protein-1 and RANTES on vitronectin-coated and, to a lesser e xtent, laminin-coated filters, whereas IgE-activated mast cells migrat ed in response to monocyte chemotactic protein-1, regulated on activat ion normal T expressed and secreted, platelet factor-4, and macrophage inflammatory protein-1 alpha on all three matrix proteins. No signifi cant migration was observed on collagen type IV-coated or uncoated fil ters. Mast cell migration in response to chemokines on extracellular m atrices and its enhancement by IgE-dependent activation provide a mech anism by which cells may be drawn to sites of inflammation. Chemokine- induced mast cell recruitment may be particularly relevant in host def ense responses to parasitic infections, allergic reactions, Jones-Mote reactions, and in wound healing.