Identification of protein disulfide isomerase and calreticulin as autoimmune antigens in LEC strain of rats

• Published in: Biochimica et biophysica acta Vol. 1158; no. 3; pp. 339 - 344
• Main Authors: Yokoi, Tsuyoshi, Nagayama, Sekio, Kajiwara, Rieko, Kawaguchi, Yasuro, Horiuchi, Ryuya, Kamataki, Tetsuya
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 28.11.1993; Elsevier
• Subjects: Amino Acid Sequence; Animals; Antigens - immunology; Antigens - isolation & purification; Autoantibodies - analysis; Autoantibodies - immunology; Autoantigen; Autoimmune; Autoimmunity; Autoimmunity (experimental aspects and models); Biological and medical sciences; Calcium-Binding Proteins - immunology; Calcium-Binding Proteins - isolation & purification; Calreticulin; Cell Membrane - enzymology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Hepatitis - immunology; Intracellular Membranes - enzymology; Isomerases - immunology; Isomerases - isolation & purification; LEC rats; Microsomes, Liver - enzymology; Molecular Sequence Data; Protein Disulfide-Isomerases; Protein isomerase; Rats; Rats, Inbred Strains; Ribonucleoproteins - immunology; Ribonucleoproteins - isolation & purification; LEC rats; Calreticulin; Autoimmune; Autoantigen; Protein isomerase; Intramolecular oxidoreductases; Rat; Enzyme; Antibody; Liver; Rodentia; Microsome; Vertebrata; Isomerases; Mammalia; Protein disulfide-isomerase
• ISSN: 0304-4165; 0006-3002; 1872-8006
• DOI: 10.1016/0304-4165(93)90033-5

Long Evans Cinnamon (LEC) rats, showing spontaneous hereditary hepatitis and hepatic carcinoma, were found to possess autoimmune antibodies to liver microsomal proteins, particularly to proteins with the molecular weight of 56kD and 55kD. The anbodies occurred in association with acute lethal hepatitis in the LEC rats in our previous study. Two-dimensional immunoblot analysis of the antigenic proteins revealed that the 56kD and 55kD proteins showed 4.2 and 4.0 pI values and were estimated to be protein disulfide isomerase (PDI) and calreticulin, respectively, from NH 2-terminal amino acid sequence analysis. These proteins were further identified by immunoblot analyses using proteins and specific antibodies. PDI was a major autoimmune antigenic protein.