Enrico Crivellato and Domenico Ribatti
Mast cells and basophils are granulated cells, which share similar phenotypic and functional properties. They express complementary and partially overlapping roles in acquired and innate immunity, including both effector and regulatory activities, but they also display important distinctive features as to developmental lineage, mediator content, and function. They cooperate in expanding and/or modulating inflammation as well as in mediating subsequent tissue repair. Mast cells release in the inflammatory scenario a series of potent proangiogenic molecules that stimulate vessel sprouting and new vessel formation. Recent data suggest that basophils may also play a role in inflammation-related angiogenesis, principally but not exclusively through the expression of several forms of VEGF and their receptors. This review focuses on the potential cooperative link between mast cells and basophils in promoting angiogenesis during allergic inflammation. We discuss the multifaceted roles of mast cells and basophils in the inflammatory setting during allergic diseases and whether these cells can be both source and target cells for proangiogenic mediators.