Group IID, IIE, IIF and III secreted phospholipase A(2)s()

Among the 11 members of the secreted phospholipase A(2) (sPLA(2)) family, group IID, IIE, IIF and III sPLA(2)s (sPLA(2)-IID, -IIE, -IIF and -III, respectively) are “new” isoforms in the history of sPLA(2) research. Relative to the better characterized sPLA(2)s (sPLA(2)-IB, -IIA, -V and -X), the enzymatic properties, distributions, and functions of these “new” sPLA(2)s have remained obscure until recently. Our current studies using knockout and transgenic mice for a nearly full set of sPLA(2)s, in combination with comprehensive lipidomics, have revealed unique and distinct roles of these “new” sPLA(2)s in specific biological events. Thus, sPLA(2)-IID is involved in immune suppression, sPLA(2)-IIE in metabolic regulation and hair follicle homeostasis, sPLA(2)-IIF in epidermal hyperplasia, and sPLA(2)-III in male reproduction, anaphylaxis, colonic diseases, and possibly atherosclerosis. In this article, we overview current understanding of the properties and functions of these sPLA(2)s and their underlying lipid pathways in vivo.