FIG 5.

The revA-deficient mutant induces higher systemic CCL-2 levels than the wild-type strain. Blood was collected at the time of sacrifice from mice infected with B. burgdorferi (B31-A3, the B31-A3ΔrevA1ΔrevA6 mutant, or the complemented strain; subcutaneous dose of 10³, 10⁴, or 10⁵ bacteria). Red blood cells were pelleted, and serum was frozen at −80°C. A commercial sandwich ELISA was used to assay CCL-2 levels according to the manufacturer's instructions (R&D Systems). Samples from 6 to 8 animals per inoculum were analyzed in triplicate. Two-way analysis of variance was used to calculate statistical differences between the groups infected with the parental strain or the B31-A3ΔrevA1ΔrevA6 mutant (P = 0.014).