CD66b, also known as CEACAM8, is a cell surface glycoprotein that is primarily expressed on granulocytes and is involved in various immune functions. It has been found to be expanded in patients with Waldenstrom macroglobulinemia (WM) and exhibits a unique inflammatory transcriptome. And the main function of CD66b is cell adhesion, cell migration, and pathogen binding. CD66b molecules were localized in lipid rafts, and disruption of lipid rafts or removal of the GPI anchor inhibited the adhesion and activation of eosinophils.