FIG. 1.

Cytokine mRNA expression induced by B. burgdorferi in PBMC from uninfected rhesus monkeys. PBMC (3 × 10⁶/ml) from uninfected rhesus monkeys were stimulated with heat-killed spirochetes of the B. burgdorferi sensu stricto strain JD1, B. afzelii ECM-1, or B. garinii G-1 (10⁷ spirochetes/ml) or with ConA (8 μg/ml) for 24 h. The induced mRNA levels of IL-10 (A), IL-2 (B), IFN-γ (C), and IL-4 (D) were determined by RT-PCR. Responses are shown as fold increases over unstimulated PBMC. Each point represents the response of PBMC from an individual monkey, and the horizontal lines indicate geometric means. All values were normalized with respect to GAPDH mRNA levels.