Induction of primary biliary cirrhosis in guinea pigs following chemical xenobiotic immunization.
Although significant advances have been made in dissecting the effector mechanisms in autoimmunity, the major stumbling block remains defining the etiological events that precede disease. Primary biliary cirrhosis (PBC) illustrates this paradigm because of its high degree of heritability, its female predominance, and its extraordinarily specific and defined immune response and target destruction. In PBC, the major autoantigens belong to E2 components of the 2-oxo-acid dehydrogenase family of mitochondrially located enzymes that share a lipoylated peptide sequence that is the immunodominant target. Our previous work has demonstrated that synthetic mimics of the lipoate molecule such as 6-bromohexoanate demonstrate a high degree of reactivity with PBC sera prompted us to immunize groups of guinea pigs with 6-bromohexanoate conjugated to BSA. In this study, we provide serologic and immunohistochemical evidence that such immunized guinea pigs not only develop antimitochondrial autoantibody responses similar to human PBC, but also develop autoimmune cholangitis after 18 mo. Xenobiotic-immunized guinea pigs are the first induced model of PBC and suggest an etiology that has implications for the causation of other human autoimmune diseases. The data also reflect the likelihood that, in PBC, the multilineage antimitochondrial response is a pathogenic mechanism and that loss of tolerance and subsequent development of biliary lesions depends on either modification of the host mitochondrial Ag or a similar breakdown due to molecular mimicry.
Division of Rheumatology, Allergy, and Clinical Immunology, University of California at Davis School of Medicine, Davis, CA 95616, USA. psleung@ucdavis.edu
Patrick S C
PS
Leung
Ogyi
O
Park
Koichi
K
Tsuneyama
Mark J
MJ
Kurth
Kit S
KS
Lam
Aftab A
AA
Ansari
Ross L
RL
Coppel
M Eric
ME
Gershwin
D000818:Animals; D001323:Autoantibodies / Q000276:immunology; D001324:Autoantigens / Q000276:immunology* / Q000378:metabolism; D001327:Autoimmune Diseases / Q000139:chemically induced / Q000201:enzymology / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D002208:Caproates / Q000633:toxicity*; D002761:Cholangitis / Q000139:chemically induced / Q000201:enzymology / Q000235:genetics / Q000276:immunology / Q000473:pathology; D051047:Dihydrolipoyllysine-Residue Acetyltransferase / Q000276:immunology*; D004195:Disease Models, Animal; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D007108:Immune Tolerance / Q000187:drug effects / Q000235:genetics / Q000276:immunology; D007114:Immunization; D008105:Liver Cirrhosis, Biliary / Q000139:chemically induced / Q000201:enzymology / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D008297:Male; D008928:Mitochondria / Q000201:enzymology / Q000276:immunology* / Q000473:pathology; D024101:Mitochondrial Proteins / Q000276:immunology* / Q000378:metabolism; D018716:Molecular Mimicry / Q000235:genetics / Q000276:immunology; D012737:Sex Factors; D015262:Xenobiotics / Q000633:toxicity*
C523145:6-bromohexanoate; D001323:Autoantibodies; D001324:Autoantigens; D002208:Caproates; D024101:Mitochondrial Proteins; D015262:Xenobiotics; D051047:Dihydrolipoyllysine-Residue Acetyltransferase