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Bacterial and viral pathogens are implicated in many severe autoimmune diseases, acting through such
mechanisms as molecular mimicry, and superantigen activation of T-cells. For example, Helicobacter pylori, well
known cause of stomach ulcers and cancers, is also identified in ischaemic heart disease (mimicry of heat shock protein
65), autoimmune pancreatitis, systemic sclerosis, autoimmune thyroiditis (HLA DRB1*0301 allele susceptibility), and
Crohn's disease. Successful antibiotic eradication of H.pylori often accompanies their remission. Yet current diagnostic
devices, and test-limiting cost containment, impede recognition of the linkage, delaying both diagnosis and therapeutic
intervention until the chronic debilitating stage. We designed a 15 minute low cost 39 antigen microarray assay,
combining autoimmune, viral and bacterial antigens1. This enables point-of-care serodiagnosis and cost-effective
narrowly targeted concurrent antibiotic and monoclonal anti-T-cell and anti-cytokine immunotherapy.
Arrays of 26 pathogen and 13 autoimmune antigens with IgG and IgM dilution series were printed in
triplicate on epoxysilane covalent binding slides with Teflon well masks. Sera diluted 1:20 were incubated 10 minutes,
washed off, anti-IgG-Cy3 (green) and anti-IgM-Dy647 (red) were incubated for 5 minutes, washed off and the slide was
read in an ArrayWoRx(e) scanning CCD imager (Applied Precision, Issaquah, WA).
As a preliminary model for the combined infectious disease-autoimmune diagnostic microarray we surveyed
98 unidentified, outdated sera that were discarded after Hepatitis B antibody testing. In these, significant IgG or IgM
autoantibody levels were found: dsDNA 5, ssDNA 11, Ro 2, RNP 7, SSB 4, gliadin 2, thyroglobulin 13 cases.
Since control sera showed no autoantibodies, the high frequency of anti-DNA and anti-thyroglobulin
antibodies found in infected sera lend increased support for linkage of infection to subsequent autoimmune disease.
Expansion of the antigen set with synthetic peptide sequences should reveal the shared bacterial/human epitopes
involved.
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