Fig 1.
Experimental timeline for the study.
Baseline values were established from T-4 until T0 with a sampling interval of 2–3 weeks. After vaccination (T0) until the end of the experiment (T12), the sampling interval was 1 week. Animals were skin tested at T9, challenged with BCG at T9 + 3 days and euthanized at T12. T(x) = time point (week number).
Fig 2.
Interferon-γ responses in the BOVIGAM® assay.
Mean OD-values in response to (A) PPD-B, (B) PPD-B minus PPD-A, (C) PPD-B minus PPD-F, (D) ESAT-6 and (E) CFP-10. = Live M. bovis BCG;
= Formalin-inactivated BCG;
= Heat-killed M. bovis; △ = Control group. Error bars indicate the standard error of the mean (±SEM) for each time point. Arrows at T0, T3 and T9 indicate priming vaccination, booster vaccination and SICTT and BCG challenge, respectively.
Fig 3.
Antibody responses in the IDEXX TB ELISA.
Mean sample/positive (S/P) ratios. = Live M. bovis BCG;
= Formalin-inactivated BCG;
= Heat-killed M. bovis; △ = Control group. Error bars indicate the SEM for each time point. Arrows at T0, T3 and T9 indicate priming vaccination, booster vaccination and SICTT and BCG challenge, respectively.
Fig 4.
Differences in skin fold thickness (A) between PPD-B and PPD-A, (B) of protein cocktail 1 and (C) of protein cocktail 2. ΔPPDB is the difference in skin fold thickness at the PPD-B injection site between 72 hrs (post injection) and 0 hrs (pre-injection). ΔPPDA is the difference in skin fold thickness at the PPD-A injection site between 72 hrs (post injection) and 0 hrs (pre-injection). Δmm is the difference in skin fold thickness of the injection site between 72 hrs (post injection) and 0 hrs (pre-injection).
Fig 5.
Log transformed bacterial counts (CFU/gram) of the right prescapular lymph nodes.
The data was log transformed to accommodate for the large variance. As several lymph nodes had shown no growth, equal to bacterial count = 0, +1 was added to all values to allow for log transformation.