TABLE 2.

Comparison of TNF-α responses by PBMC from M. bovis-infected cattle to responses by cattle naturally sensitized to M. avium

GroupTNF-α responsea to recall antigen:
PPDaPPDbrESAT-6:CFP-10
M. bovis-infected (6 mo postinfection)0.316 (0.084)1.370b (0.524)0.790b (0.285)
M. avium-exposed (natural exposure)0.164 (0.048)0.056 (0.052)0.038 (0.095)
  • a Values are the mean TNF-α responses (in nanograms per milliliter) (n = 8) of PBMC to antigen stimulation minus their response to medium alone after 48 h. Values in parentheses are the standard errors of the means.

  • b Significantly different from the response by M. avium-exposed cattle (P < 0.05).