Precipitating antibodies to rabbit thymus extractable antigens in chronic liver disease: relationship with anti-actin antibodies.
Using counterimmunoelectrophoresis (CIE), serum antibodies to rabbit thymus extractable antigens were detected in 15% (38/259) of patients with chronic liver disease (CLD) of various aetiologies and 33% (41/124) of patients with miscellaneous connective tissue diseases (CTD). A remarkable diversity of precipitating systems was apparent among cases with the two classes of disorders. All the five systems found in CLD (XR, XR2, SS-B, XR3, XR4) were associated mostly with immunological hepatic disorders. In the 52 autoimmune hepatitis cases, XR was mainly detected (29%), whereas in the 82 primary biliary cirrhosis patients the whole spectrum of reactivities was represented (XR: 11%, XR2: 10%, SS-B and XR3: 2% each, XR4: 1%). XR proved to be closely associated with smooth muscle antibodies (SMA, detected by indirect immunofluorescence on rat kidney sections) both qualitatively and quantitatively. Since all SMA positive sera with anti-actin specificity (SMAT, SMAG) were XR positive and purified actin could absorb out XR CIE reactivity, the hypothesis is made that a cross-reaction occurs between XR antigen and actin epitope(s).
Cassani
F
F
Istituto di Patologia Medica, Cattedra di Clinica Medica II, University of Bologna, Italy.
Fusconi
M
M
Bianchi
F B
FB
Selleri
L
L
Baffoni
L
L
Lenzi
M
M
Pisi
E
E
D000199:Actins / Q000276:immunology*; D001323:Autoantibodies / Q000032:analysis*; D001324:Autoantigens / Q000276:immunology*; D002908:Chronic Disease; D003240:Connective Tissue Diseases / Q000276:immunology; D003378:Counterimmunoelectrophoresis; D005455:Fluorescent Antibody Technique; D006801:Humans; D008107:Liver Diseases / Q000276:immunology*; D011234:Precipitins / Q000032:analysis*; D013950:Thymus Gland / Q000276:immunology*
D000199:Actins; D001323:Autoantibodies; D001324:Autoantigens; D011234:Precipitins