The pivotal role of C1qR in mixed cryoglobulinemia

Abstract

Non-enveloped HCV core protein, a constitutive antigen component of cryoglobulins in HCV-infected patients, is required for generating cryoglobulin-mediated tissue injury in vivo upon engagement of the globular domain of C1q receptor (gC1qR). gC1qR is proteolytically cleaved from the cell surface, suggesting that the cleavage event is physiologically relevant. Circulating gC1qR may affect numerous aspects of cell biology via intracellular and extracellular pathways. Higher serum levels of gC1qR in mixed cryoglobulinemia indicate that this protein plays a relevant role in the pathogenesis of cryoglobulin-related damage, including immune complex formation and cryoprecipitation.