CD8(-CELLS ARE ACTIVATED DURING THE EARLY TH1 AND TH2 IMMUNE-RESPONSES IN A MURINE LYME-DISEASE MODEL() T)

T-helper responses following Borrelia burgdorferi infection in mice de termine susceptibility to Lyme arthritis. The ratio of interleukin 4-p ositive, CD4(+) to gamma interferon (IFN-gamma)-positive, CD4(+) T cel ls was significantly greater in infected BALB/cJ mice than in infected C3H/HeJ mice. Increased numbers of IFN-gamma-producing cells predicte d greater arthritis severity, and CD8(+) T cells were the main source of IFN-gamma in both strains.