Etiopathogenesis of primary sclerosing cholangitis

Table 6 Evidence for the influence of immune mechanisms on the aetiology of PSC

	Evidence for the influence of immune mechanisms
Humoral immunity	Increased circulating immune complexes
	Elevated immunoglobulin levels (IgG and IgM)
	Low titres of non-organ specific autoantibodies (ANA and SMA)
	High titres of antineutrophil nuclear antibody (ANNA)
Cell mediated immunity	Decreased levels of circulating peripheral CD8+ve Tcells
	Portal T cell and NK cell infiltrate
	Increased activated and memory T cells
	Restricted T cell receptor repertoire (Vβ3)
	Aberrant expression of HLA-DR on BEC
	Coexpression of costimulatory molecules and HLA-DR on BECs
	Abnormal expression of adhesion molecules on biliary epithelial cells
	Abnormal expression of chemokine ligands on biliary epithelial cells
Immune effector mechanisms	Enhanced cytokine expression in the liver
Immunogenetic mechanisms	HLA associations