Ribophorin ii is involved in the tissue factor expression mediated by phosphatidylserinedependent antiprothrombin antibody on monocytes

Yuichiro Fujieda, Olga Amengual, Masaki Matsumoto, Kimiko Kuroki, Hidehisa Takahashi, Michihito Kono, Takashi Kurita, Kotaro Otomo, Masaru Kato, Kenji Oku, Toshiyuki Bohgaki, Tetsuya Horita, Shinsuke Yasuda, Katsumi Maenaka, Shigetsugu Hatakeyama, Keiichi I. Nakayama, Tatsuya Atsumi

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Objective. Phosphatidylserine-dependent, also called aPS-PT, recognizes the phosphati dylserine prothrombin complex, which is associated with APS. We have previously reported that aPSPT induces tissue factor (TF) expression on monocytes through the p38 mitogen-activated protein kinase pathway. However, the cell surface interaction between prothrombin and aPS-PT, which is involved in the activation of cell-signalling pathways, has remained unknown. The objective of this study was to identify membrane proteins involved in the binding of prothrombin and aPS-PT to monocyte surfaces as well as the induction of TF expression. Methods. RAW264.7 cells with FLAG-tagged prothrombin were incubated and separated using affinity chromatography with anti-FLAG antibody-conjugated Sepharose beads. Immunopurified proteins were then analysed by an online nano-liquid chromatography tandem mass spectrometry. The binding between prothrombin and the identified protein, ribophorin II (RPN2), was analysed by ELISA and surface plasmon resonance. To elucidate the role of RPN2 in TF expression, the TF mRNA level in RAW264.7 cells treated with RPN2 small interfering RNA was determined by quantitative real-time PCR (qPCR). Results. RPN2 was identified as a candidate molecule involved in the binding of prothrombin to the cell surface. The binding between prothrombin and RPN2 was confirmed by ELISA and surface plasmon resonance. RAW264.7 cells treated with RPN2 small interfering RNA showed significant reduction of the TF expression mediated by prothrombin and a mouse monoclonal aPS-PT. Conclusion. We identified that RPN2 is one of the prothrombin-binding proteins on monocyte surfaces, suggesting that RPN2 is involved in the pathophysiology of thrombosis in patients with APS.

Original languageEnglish
Pages (from-to)1117-1126
Number of pages10
JournalRheumatology (United Kingdom)
Volume55
Issue number6
DOIs
Publication statusPublished - 2016 Jun 1

Keywords

  • Anti-phospholipid antibodies
  • Anti-phospholipid syndrome
  • Lupus anticoagulant
  • Prothrombin

ASJC Scopus subject areas

  • Rheumatology
  • Pharmacology (medical)

Fingerprint Dive into the research topics of 'Ribophorin ii is involved in the tissue factor expression mediated by phosphatidylserinedependent antiprothrombin antibody on monocytes'. Together they form a unique fingerprint.

  • Cite this

    Fujieda, Y., Amengual, O., Matsumoto, M., Kuroki, K., Takahashi, H., Kono, M., Kurita, T., Otomo, K., Kato, M., Oku, K., Bohgaki, T., Horita, T., Yasuda, S., Maenaka, K., Hatakeyama, S., Nakayama, K. I., & Atsumi, T. (2016). Ribophorin ii is involved in the tissue factor expression mediated by phosphatidylserinedependent antiprothrombin antibody on monocytes. Rheumatology (United Kingdom), 55(6), 1117-1126. https://doi.org/10.1093/rheumatology/kew005