FIG. 3.

B. burgdorferi-infected MyD88^−/− mice have higher bacterial loads in all inflamed organs. MyD88^−/− and MyD88^+/+ mice were infected with B. burgdorferi as described in Materials and Methods and sacrificed 3 weeks after infection. DNA was isolated from joint, muscle, and kidney tissues and processed to quantitate B. burgdorferi DNA levels using real-time RT-PCR for a single-copy B. burgdorferi gene, recA. Numbers represent copies of B. burgdorferi recA normalized to the weight of tissue used to isolate DNA. Ten mice each were used for studies of wild-type (WT) and MyD88^−/− (knockout [KO]) joints and muscle tissue; five mice each were used for studies of kidney tissue. ***P < 0.001; **P < 0.01.