OBJECTIVEIt is known that Siglec-8 is selectively expressed on human eosinophils at a high level and mediates eosinophil apoptosis when crosslinked with its antibody. The aim of our review is to elucidate the molecular and biological characteristic of Siglec-8 and then discuss the function and possible mechanisms of Siglec-8 in eosinophils. Thereby, we will expand our understanding to the regulation of eosinophil apoptosis, and provide important clues to the treatment of asthma and other hyper-eosinophilic diseases.

DATA SOURCESMost articles were identified by searching of PubMed online resources using the key term Siglecs.

STUDY SELECTIONMainly original milestone articles and critical reviews written by major pioneer investigators in the field were selected.

RESULTSSiglec-8 is selectively expressed on human eosinophil and can specifically induce eosinophil apoptosis.

CONCLUSIONThe restricted expression of Siglec-8 on human eosinophil and the rapid progress in understanding its role as cell signaling and activation of death receptors have made it an attractive target for treatment of asthma and other hyper-eosinophilic diseases.