Autoantibody response to microsomal epoxide hydrolase in hepatitis C and A

Abstract

Autoimmune responses were observed in a large proportion of hepatitis C cases and are suspected to be part of viral pathogenesis. The AN6520 antigen (AN-Ag) is a normal cellular protein mainly expressed in liver that was found associated with non-A, non-B hepatitis. To elucidate its pathogenic role in hepatitis C, we developed an IgM capture assay using purified AN-Ag and confirmed that the antibody response to AN-Ag is associated almost exclusively with hepatitis C cases (29%). Screening of a human liver expression library revealed that AN-Ag is mainly the microsomal epoxide hydrolase (mEH), a drug-metabolizing enzyme that plays an important role in the metabolism of some mutagenic and carcinogenic epoxides. Using the purified recombinant human mEH as an antigen, we now found that antibodies against this protein are associated with nearly 82% of hepatitis C virus infections and surprisingly with 46% of patients with hepatitis A. The appearance of AN-Ag/mEH in the incubation period of hepatitis C as previously reported and the antibody responses shown here indicate that this enzyme may be a marker for or even a cause of some of the pathology associated with hepatitis C and A.

Monosodium glutamate (MSG): A villain and promoter of liver inflammation and dysplasia

“…In parallel with the rise of the metabolic syndrome within the internal medicine field [16], NAFLD is rapidly becoming the leading cause of hepatologist evaluation [3] and NASH is estimated to overcome chronic viral hepatitis as the most frequent indication to liver transplantations in the next decade [7]. Further, NASH shares the capacity to evolve to fibrosis, frank cirrhosis, and HCC [3] and its discrimination from other forms of liver steatosis relies only on histology while additional players cannot be ruled out, similar to what observed in other conditions [17,18].…”

Prevalence of hepatitis C serum antibody in autoimmune diseases

“…The occurrence of serum autoantibodies in HCV-infected patients has been extensively studied, and an increased prevalence of anti-nuclear, anti-cardiolipin, anti-smooth muscle and antithyroglobulin antibodies was reported as compared with uninfected controls, alongside high levels of cryoglobulins and rheumatoid factor [28,33,73,74]. Anti-nuclear antibodies have been detected in 10-30% of HCV-infected patients and their presence correlates with older age [75,76].…”

The Catastrophic Antiphospholipid Syndrome in Serbia: Diagnostic and Management Problems

“…This is beyond the scope of this review but we note this literature. It would certainly be literature that Dr. Ron Asherson would have enjoyed reading [20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37].…”