TABLE 2.

E. chaffeensis infections in mice lacking functional tlr4 gene results in the short-term persistencea

DayNo. positive/no. tested (%)Pb
tlr4n/n and MHC-II+/+ micetlr4d/d and MHC-II+/+ mice
84/4 (100)4/4 (100)NS
160/4 (0)4/4 (100)0.005
230/3 (0)2/2 (100)0.025
300/3 (0)2/4 (50)0.138
500/4 (0)0/4 (0)NS
920/4 (0)0/4 (0)NS
  • a Peritoneal exudate cells were recovered from mice at the indicated times after i.p. infection with E. chaffeensis and were used to recover E. chaffeensis by culture in DH82 cells. Cultures were maintained for up to 8 weeks and examined twice a week for the presence of organisms. Cultures were monitored for growth every three to four days until the recovery of viable organisms.

  • b Statistical analysis was performed by the chi-square test. NS, not statistically significant.