ab1802

Broadening of the T cell receptor spectrum among rheumatoid arthritis synovial cell-lines in relation to disease duration

D. Elewaut*, F. De Keyser*, F. Van Den Bosch, G. Verbruggen, E.M. Veys

Department of Rheumatology, University Hospital Ghent, Belgium

ABSTRACT
Objective
The aim of the study was to evaluate the T cell receptor (TCR) family usage in T cell-lines from sub-cutaneous nodules and synovium from patients with rheumatoid arthritis (RA), with specific reference to the duration of symptoms. In vitro adherence characteristics of nodular T cells was studied as well.

Methods
Monoclonal antibodies were used to determine the distribution of TCR families in T cell-lines from synovium of patients with early and long-standing RA, from rheumatoid nodules and control tissues. An in vitro binding assay with T cell-lines from 2 rheumatoid nodules was performed.

Results
In early RA synovium, a restricted TCR family usage was observed in 5 out of 8 patients, contrary to long-standing disease, peripheral blood, ileum and colon. In RA nodules, a similar degree of restriction was noted. Moreover, the same TCR family was overexpressed by T cell-lines from different nodules derived from the same patient. T cell-lines from rheumatoid nodules demonstrated a preferential in vitro adherence to rheumatoid synovium and rheumatoid nodules, while no binding was observed on skin or tonsil.

Conclusion
The TCR spectrum among RA synovial cell-lines broadens in relation to the disease duration. The overexpression of the same TCR family in different rheumatoid nodules from the same patients, and the in vitro adherence of T cell-lines from rheumatoid nodules may be indicative for recirculation between the different disease manifestations in RA.

Key words
T cell receptor, rheumatoid arthritis, rheumatoid nodules, rheumatoid synovium.

*The contributions of both authors were equal; therefore they should both be considered as first authors.

This work was supported by FWO-Vlaanderen grant 3.0028.95 and by a concerted action grant GOA96001 of the University of Ghent, Belgium. Dirk Elewaut is a FWO-Vlaanderen research assistant.

Please address correspondence and reprint requests to: Filip De Keyser, MD, PhD, Department of Rheumatology 0K12IB, University Hospital Ghent, De Pintelaan 185, B-9000 Ghent, Belgium.
E-mail: FILIP.DEKEYSER@RUG.AC.BE