Immunization with Recombinant Escherichia coli Expressing Retinal S-Antigen-Induced Experimental Autoimmune Uveitis (EAU) in Lewis Rats

Previously we have reported that microbial proteins having sequence homology with uveitopathogenic peptide (peptide M) of retinal S-antigen (S-Ag) induced experimental autoimmune uveitis (EAU) in Lewis rats and subhuman primates. In order to evaluate the role of natural microbial infections in causing autoimmune diseases we have constructed a recombinant Escherichia coli expressing retinal S-Ag when injected it into Lewis rats which developed EAU. Control animals immunized with E. coli JM105 transfected with only plasmid DNA did not induce EAU, Similarly, bakerʹs yeast (Saccharomyces cerevisiae), which has six amino acid residues in histone H3 identical with peptide M of S-Ag, induced EAU when injected into rats. Lymph node cells of rats immunized with recombinant E. coli or with the yeast show significant proliferative responses against peptide G and peptide M of S-Ag, respectively. The animals immunized with recombinant E. coli also produced antibody to S-Ag.