APRIL—a cytokine, member of the TNF superfamily, and B-cell growth factor—plays a key role in5:
B-cell activation
Mucosal IgA production
The survival of long-lived plasma cells
Ig isotype class-switching
The proliferated Gd-IgA1 leads to autoantibody production, immune complex formation, inflammation, and kidney injury.5
APRIL=A PRoliferation-Inducing Ligand; Gd-IgA1=galactose-deficient immunoglobulin A1; Ig=immunoglobulin; IgA=immunoglobulin A; IgAN=immunoglobulin A nephropathy; TNF=tumor necrosis factor.
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