Shahriar Amjadi, Kelly Mai, Peter McCluskey,Denis Wake?eld

Purpose:
To determine the role of exposure to Chla-mydia trachomatis in the pathogenesis of HLA-B27related Acute Anterior Uveitis and SeronegativeArthritis.

Method:
Peptide sequences derived from lumican, aproteoglycan present in the eye and cartilage, wereshown to have sequence homology with Chlamydiatrachomatis. These peptide sequences were examinedfor their role as potential antigens in patients withAcute Anterior Uveitis and Seronegative Arthritis. 37patients and nine healthy controls were recruited formeasurement of T cell responses using an interferon-gamma ELISPOT assay. 17 patients and six healthycontrols were recruited for measurement of T cell acti-vation to putative antigens by measurement of cellsurface activation markers.

Results:
Patients showed greater responses to groupsof peptides from lumican (51.4% vs 11.1%),extracellular components (45.7% vs 22.2%) and Chla-mydia trachomatis (37.1% vs 11.1%). Though theresults were not statistically signi?cant (Two-tailedFisher exact test), a trend was observed. Similarly,using ?ow cytometric methods a higher proportion ofpatients were found to respond to seven of the eightantigens tested, including whole recombinantlumican.

Conclusion:
Chlamydia trachomatis and/or lumicanmay play an antigenic role in HLA-B27-related AcuteAnterior Uveitis and Seronegative Arthritis. Studieswith larger numbers of patients may need to be under-taken to further elucidate the role of these potentialantigens.