TABLE 1.

CpG ODN 1826 induces protective immunity against challenged with B. pseudomallei

TreatmentaDay of adminis- trationDose (no. of LD50)No. that survivedb/ total no.% Pro- tectionPc
CpG ODN 1826−15104/7570.0125
−10107/71000.0001
−5107/71000.0001
−2106/61000.0002
PBS−2100/8
CpG ODN 1826d−21011/12920.0001
−25016/18890.0001
Control ODN 1982−2100/120
−2500/120
PBS−2100/120
−2500/200
CpG ODN 18260102/6330.1213
1100/60
PBS0100/60
  • a A 100-μg amount of CpG ODN 1826, control ODN 1982, or PBS was administered in the tibialis anterior muscle on the day indicated relative to an intraperitoneal challenge with B. pseudomallei on day 0.

  • b As observed on day 30, when the experiments were terminated.

  • c P values were calculated by comparing protection induced by CpG ODN 1826 treatment with that induced by control ODN 1982 or PBS on each of days −15, −10, −5, −2, 0, and 1 relative to the bacterial challenge on day 0, using the chi-square test.

  • d The day −2 protocol was repeated several times with similar results and was used in the remaining part of this study.