DETECTION OF BORRELIA-BURGDORFERI-SPECIFIC CD8(-CELLS IN PATIENTS WITH LYME ARTHRITIS() CYTOTOXIC T)

T cells are believed to play an important role in the pathogenesis of Lyme arthritis (LA), an inflammatory joint disease caused by the spiro chete Borrelia burgdorferi (Bb), The presence or absence of certain Bb -specific CD4(+) T helper cells has been associated with prognosis, Si nce recent observations suggested the activation of CD8(+) T cells dur ing infection with Bb, we searched for CD8(+) cytotoxic T lymphocytes in patients with LA, CD8(+) T cell lines were generated from periphera l blood and synovial fluid of five patients with LA, In addition, CD8( +) T cells were expanded by Ag-specific stimulation in bulk cultures, A cytotoxicity assay was established using target cells infected with recombinant vaccinia viruses expressing the borrelial proteins outer s urface protein (Osp) A, OspB, or flagellin, We found Bb-specific CTL l ines derived from the peripheral blood of three patients with LA with specificity for flagellin, OspA, and OspB, All Bb-specific CTL lines w ere CD3(+), CD8(+), and TCR alpha beta(+), and cytotoxic activity was HLA class I restricted, Moreover, CD8(+) T cells expanded by Ag-specif ic stimulation in vitro demonstrated Bb-specific and HLA class I-restr icted lysis toward individual borrelial proteins, Interestingly, Bb-sp ecific lytic activity was only detected in patient samples obtained af ter the disappearance of arthritis. We report the detection of Bb-spec ific cytotoxic CD8(+) T cells in patients with LA, The induction of sp ecific CD8(+) T cells may play an important role in disease control an d may have important bearings for the development of effective vaccine s against Lyme borreliosis.