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Clinical and Experimental Nephrology

, Volume 14, Issue 1, pp 51–55 | Cite as

Phosphorylation status of nephrin in human membranous nephropathy

  • Teiko Ohashi
  • Keiko UchidaEmail author
  • Yukari Asamiya
  • Yuki Tsuruta
  • Mayuko Ohno
  • Shigeru Horita
  • Kosaku Nitta
Original Article

Abstract

Background

We recently reported that nephrin, a major slit-diaphragm protein, is phosphorylated at Y1204 and Y1228 in normal human glomeruli and that phosphorylation decreased significantly in minimal-change nephrosis. These results indicate that phosphorylation of nephrin is important for maintenance of normal podocyte morphology and function. On the other hand, phosphorylation of nephrin was reportedly increased in certain animal models of glomerular injury.

Methods

We performed immunofluorescent and immunoelectron staining of phosphorylated nephrin in human kidney biopsy specimens of membranous nephropathy (MN) to investigate whether phosphorylation of nephrin was altered in human MN and whether it correlated with MN staging.

Results

Although aberrant localization of phosphorylated nephrin was detected using immunoelectron microscopy in stage I MN, a decrease in the immunofluorescent intensity of phosphorylated nephrin was not observed in stage I, and only a slight decrease was seen in stages II, III, and IV compared with controls. No significant correlation between nephrin phosphorylation and proteinuria was observed.

Conclusion

Nephrin phosphorylation was not significantly decreased in the early stage of MN.

Keywords

Nephrin Phosphorylation Immunofluorescence Immunoelectron microscopy Kidney biopsy 

Notes

Acknowledgments

We thank Ms. K. Sasaki for technical assistance.

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Copyright information

© Japanese Society of Nephrology 2009

Authors and Affiliations

  • Teiko Ohashi
    • 1
  • Keiko Uchida
    • 1
    Email author
  • Yukari Asamiya
    • 1
  • Yuki Tsuruta
    • 1
  • Mayuko Ohno
    • 1
  • Shigeru Horita
    • 1
  • Kosaku Nitta
    • 1
  1. 1.Department of Medicine, Kidney CenterTokyo Women’s Medical UniversityTokyoJapan

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