The ubiquitin-proteasome pathway and IgA nephropathy: a novel link?

Proteasomal degradation of intracellular proteins facilitates the recognition of foreign proteins through interactions with major histocompatibility complex molecules presented to T cells. Interferon-γ enhances the efficiency of this antigen presentation process by inducing a switch of proteasome to immunoproteasome catalytic subunits. The finding that immunoproteasomes are upregulated in IgA nephropathy may prompt further exploration of the role and mechanism of proteasome activation and intensify the quest for infectious agents that may induce IgA nephritis