Anti-mitochondrial antibody immunofluorescent titres correlate with the number and intensity of immunoblot-detected mitochondrial bands in patients with primary biliary cirrhosis.
BACKGROUND
Primary biliary cirrhosis (PBC)-specific anti-mitochondrial antibodies (AMA), routinely detected by indirect immunofluoresnce, immunofix various mitochondrial antigens by immunoblot (IB). We have investigated whether there is a relationship between IFL-determined AMA titres and the number, intensity or pattern of IB-bands.


METHODS
By computer-assisted imaging technology, an IB analysis using human liver mitochondrial preparation was performed in 100 AMA positive PBC samples, subdivided in 5 groups each consisting of 20 cases with very high, high, intermediate, low or borderline IFL titres and in 19 AMA-negative cases.


RESULTS
Reactivity to at least 1 mitochondrial band (range 1-12) was present in 114 (96%) cases. Reactivity to the major pyruvate dehydrogenase E2-subunit 74-kDa autoantigen positively correlated with AMA IFL titres but was absent in 25% IFL-positive cases. The intensity and number of IB-bands differed significantly among groups (p<0.001). IFL AMA titres positively correlated with the total number (r=0.8, p<0.001) and the intensity of the IB-bands (r=0.75, p<0.001).


CONCLUSIONS
Our study indicates that IFL-determined AMA relate to the number and intensity of immunofixed bands. Reactivity to PDC-E2 does not correlate with IFL titres in a considerable proportion of patients suggesting that detection methods of AMA need to be based in the entire spectrum of the disease-specific mitochondrial antigens.
Rigopoulou
Eirini I
EI
Academic Liver Unit and Research Laboratory of Internal Medicine, Department of Medicine, Larissa Medical School, University of Thessaly, Larissa 41222, Greece.
Bogdanos
Dimitrios-Petrou
DP
Liaskos
Christos
C
Koutsoumpas
Andreas
A
Baum
Harold
H
Vergani
Diego
D
Dalekos
George N
GN
D001323:Autoantibodies / Q000097:blood*; D001324:Autoantigens / Q000276:immunology*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D015151:Immunoblotting; D007159:Immunologic Tests; D008105:Liver Cirrhosis, Biliary / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D008930:Mitochondria, Liver / Q000276:immunology*
D001323:Autoantibodies; D001324:Autoantigens