Basophil
Chapter: 2
The least common leukocyte, which has many intracytoplasmic granules that stain intensely basophilic in routine hematologic preparations. They are very similar to mast cells, both in terms of their appearance and functions; however, they are a completely distinct cell type. One distinguishing feature of both basophils and mast cells is their complement of IgE receptors, potentially making them important contributors to allergic responses. They are a rich source of vasoactive mediators, such as histamine, leukotrienes, and platelet activating factor. Additionally, they produce chemotactic factors for neutrophils and eosinophils.