B-cell-independent sialylation of IgG.
Proc Natl Acad Sci U S A
; 113(26): 7207-12, 2016 06 28.
Article
in En
| MEDLINE
| ID: mdl-27303031
ABSTRACT
IgG carrying terminal α2,6-linked sialic acids added to conserved N-glycans within the Fc domain by the sialyltransferase ST6Gal1 accounts for the anti-inflammatory effects of large-dose i.v. Ig (IVIg) in autoimmunity. Here, B-cell-specific ablation of ST6Gal1 in mice revealed that IgG sialylation can occur in the extracellular environment of the bloodstream independently of the B-cell secretory pathway. We also discovered that secreted ST6Gal1 is produced by cells lining central veins in the liver and that IgG sialylation is powered by serum-localized nucleotide sugar donor CMP-sialic acid that is at least partially derived from degranulating platelets. Thus, antibody-secreting cells do not exclusively control the sialylation-dependent anti-inflammatory function of IgG. Rather, IgG sialylation can be regulated by the liver and platelets through the corresponding release of enzyme and sugar donor into the cardiovascular circulation.
Key words
Full text:
1
Database:
MEDLINE
Main subject:
Sialic Acids
/
Sialyltransferases
/
Immunoglobulin G
/
B-Lymphocytes
Limits:
Animals
Language:
En
Year:
2016
Type:
Article