RRC ID 42305
著者 Hattori N, Ikekubo K, Nakaya Y, Kitagawa K, Inagaki C.
タイトル Immunoglobulin G subclasses and prolactin (PRL) isoforms in macroprolactinemia due to anti-PRL autoantibodies.
ジャーナル J Clin Endocrinol Metab
Abstract Although macroprolactinemia due to antiprolactin (anti-PRL) autoantibodies is not uncommon among hyperprolactinemic patients, the pathogenesis of such macroprolactinemia is still unknown. We examined IgG subclasses of anti-PRL autoantibodies by enzyme immunoassay, and PRL phosphorylation and isoforms by Western blotting, mass spectrometry, and two-dimensional electrophoresis in six patients with anti-PRL autoantibodies and in 29 controls. PRL-specific IgG subclasses in patients with anti-PRL autoantibodies were heterogeneous, but five of six patients showed IgG4 predominance, which is known to be produced by chronic antigen stimulation. Western blot and mass spectrometric analyses revealed that human pituitary PRL was phosphorylated at serine 194 and serine 163, whereas serine 163 in serum PRL was dephosphorylated. On two-dimensional electrophoresis, serum PRL mainly consisted of isoform with isoelectric point (pI) 6.58 in control hyperprolactinemic patients, whereas acidic isoforms (pIs 6.43 and 6.29) were also observed in patients with anti-PRL autoantibodies. Our data first demonstrate that human pituitary PRL is serine phosphorylated and partially dephosphorylated in serum, and suggest that the acidic isoforms may give rise to chronic antigen stimulation in patients with anti-PRL autoantibodies.
巻・号 90(5)
ページ 3036-44
公開日 2005-5-1
DOI 10.1210/jc.2004-1600
PII jc.2004-1600
PMID 15687336
MeSH Adult Amino Acid Sequence Autoantibodies / blood* Blotting, Western Female Humans Middle Aged Molecular Sequence Data Phosphorylation Prolactin / blood* Prolactin / immunology* Protein Isoforms Serine / metabolism Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
IF 5.399
引用数 27
WOS 分野 ENDOCRINOLOGY & METABOLISM
リソース情報
ヒト・動物細胞 Jurkat(RCB0806)