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Updated: Jun 26, 2026

Generation of Monocyte-Derived Dendritic Cells with Differing Sialylated Phenotypes
Published on: October 20, 2023
B cell antigen receptor signal strength and peripheral B cell development are regulated by a 9-O-acetyl sialic acid
Annaiah Cariappa1, Hiromu Takematsu, Haoyuan Liu
1Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA.
Abstract:
We show that the enzymatic acetylation and deacetylation of a cell surface carbohydrate controls B cell development, signaling, and immunological tolerance. Mice with a mutation in sialate:O-acetyl esterase, an enzyme that specifically removes acetyl moieties from the 9-OH position of alpha2-6-linked sialic acid, exhibit enhanced B cell receptor (BCR) activation, defects in peripheral B cell development, and spontaneously develop antichromatin autoantibodies and glomerular immune complex deposits. The 9-O-acetylation state of sialic acid regulates the function of CD22, a Siglec that functions in vivo as an inhibitor of BCR signaling. These results describe a novel catalytic regulator of B cell signaling and underscore the crucial role of inhibitory signaling in the maintenance of immunological tolerance in the B lineage.
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