Anti-retinal S-antigen antibodies in human sera: a comparison of reactivity in ELISA with human or bovine S-antigen

Int Ophthalmol. 1992 May;16(3):147-52. doi: 10.1007/BF00916433.


Various studies have demonstrated anti-retinal S-antigen (S-ag) antibodies in uveitis sera in assays using bovine S-ag. Because of its molecular similarity and cross-reactivity with human S-ag, reactions with bovine S-ag have been considered a reliable indication of anti-S-ag autoimmunity. To test this assumption, the cross-reactivity of purified human and bovine S-ags was quantitated by ELISA titration of various anti-human and anti-bovine S-ag immune reagents raised in mice, rats and rabbits. Anti-human S-ag reagents appeared to be largely cross-reactive with bovine S-ag, whereas anti-bovine S-ag reagents were 6-10 times less reactive with the cross-reacting human S-ag than with bovine S-ag, thus showing a predominant role of species-specific epitopes on bovine S-ag. Furthermore, a large number of human control and uveitis sera was tested in ELISA with both human S-ag- and bovine S-ag-coated microwells. Both the numbers of positive sera and the levels of anti-S-ag antibodies in the two tests significantly correlated, but many exceptions were found, and the predictive value of reactions with bovine S-ag for the presence and levels of anti-S-ag autoantibodies was low. For individual human sera, assessment of anti-S-ag autoantibodies requires the use of human S-ag in immunoassays.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Antigens / immunology*
  • Arrestin
  • Autoantibodies / blood*
  • Autoantigens / immunology*
  • Cattle
  • Cross Reactions / immunology*
  • Enzyme-Linked Immunosorbent Assay
  • Eye Proteins / immunology*
  • Humans
  • Mice
  • Predictive Value of Tests
  • Rabbits
  • Species Specificity
  • Uveitis, Anterior / immunology*
  • Uveitis, Posterior / immunology*


  • Antigens
  • Arrestin
  • Autoantibodies
  • Autoantigens
  • Eye Proteins