J Exp Med 1985 May 1;161(5):1231-6

Anti-liver-kidney microsome antibody recognizes a 50,000 molecular weight
protein of the endoplasmic reticulum.

Alvarez F, Bernard O, Homberg JC, Kreibich G

Abstract
Children with autoimmune chronic active hepatitis may have high titers of
antibodies detected by immunofluorescence staining of hepatocytes and tubular
cells in rat liver and kidney sections, respectively. These antibodies are
directed against antigens contained in microsomal fractions prepared from these
two organs. We have found that sera from these patients recognized a 50,000 mol
wt protein present in higher concentration in smooth microsome subfractions
compared with rough microsome subfractions. This protein is an integral membrane
protein and is not glycosylated. It is exposed on the cytoplasmic face of the
endoplasmic reticulum and is rather resistant to proteolysis with proteinase K.
Since patients with liver disease of different etiology and similar severity of
cell lysis do not give rise to liver-kidney microsome antibody (LKMA), lysis of
hepatocytes is apparently not a sufficient condition for their development