Induction of anti-Ro60/anti-La by immunisation with spectrin and induction of anti-spectrin by immunisation with Ro60 and 4-hydroxy-2-nonenal-modified Ro60 immunisation

Clin Exp Rheumatol. 2012 Nov-Dec;30(6):886-93. Epub 2012 Dec 17.


Objectives: The Ro ribonucleoprotein particle, targeted in systemic lupus erythematosus (SLE) and Sjögren's syndrome (SS), includes Ro60 (SSA) and La (SSA) autoantigens. Anti-Ro60 occurs in SLE and SS. The importance of α-fodrin and spectrin as well as anti-Ro and anti-fodrin/spectrin antibodies in SS and SLE, led us to hypothesise that rabbit immunisation with Ro60 or 4-hydroxy-2-nonenal-modified Ro60 would induce anti-spectrin. In addition, we hypothesised that antibodies to Ro60 and La will develop in animals immunised with spectrin.

Methods: Two NZW rabbits each were immunised with 4-hydroxy-2-nonenal-modified Ro60 or unmodified Ro60. Methods used included ELISA, including an inside-out RBC membrane ELISA, and Crithidia lucilae assays.

Results: Commercial anti-spectrin sera bound significantly to Ro60 (OD 2.6 ± 0.1), Ro60 multiple antigenic peptides (MAPs) (3 out of 21 Ro60 MAPs), La (OD 4.4±0.5), and La fragments as well as to double stranded DNA but not to BSA (OD 0.6±0.1). Anti-spectrin binding to purified spectrin could be inhibited by spectrin (>95%), and Ro60 or La (70%). When the binding of anti-spectrin was tested against a nested set of La fragments we found that a N4 fragment representing the C-terminal 250 aa (aa 159 to 408) bound the strongest (OD=4.12) followed by a N9 fragment (the C-terminal 36aa; aa373 to 408 (OD=1.36). Also, significant anti-spectrin antibody levels were induced by Ro60 and HNE-modified Ro60 immunisation.

Conclusions: We found intermolecular epitope spreading from Ro60/La to spectrin and vice versa, and this may have pathological significance in these animal models of autoimmunity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aldehydes / administration & dosage
  • Aldehydes / immunology*
  • Animals
  • Antibodies, Antinuclear / blood*
  • Autoantigens / immunology*
  • Autoimmunity*
  • Binding, Competitive
  • DNA / metabolism
  • Enzyme-Linked Immunosorbent Assay
  • Epitope Mapping
  • Epitopes
  • Immunization*
  • Protein Binding
  • Rabbits
  • Ribonucleoproteins / administration & dosage
  • Ribonucleoproteins / immunology*
  • Spectrin / administration & dosage
  • Spectrin / immunology*


  • Aldehydes
  • Antibodies, Antinuclear
  • Autoantigens
  • Epitopes
  • Ribonucleoproteins
  • SS-A antibodies
  • SS-A antigen
  • SS-B antibodies
  • SS-B antigen
  • Spectrin
  • DNA
  • 4-hydroxy-2-nonenal