The comparative frequency of IFNγ secreting cells responding to mycobacterial antigens does not appear to be affected by different vaccination regimes.

<p>The frequency of IFNγ producers in PBMC, as determined by ELISpot, from animals immunised with BCG at week 0 and challenged with 2000 cfu <i>M</i>. <i>bovis</i> at week 12 was determined as indicated in materials and methods; immunisation and challenge are indicated by arrows on the <i>x</i> axis. IFNγ ELISpot was evaluated at the weeks indicated on the <i>x</i> axis, corrected for background and expressed as spot forming units (SFU) per 10⁶/PBMC. No significant differences in the frequency of IFNγ secreting cells responding to PPD-B, Rv0288 or r85A was detected between the different vaccination regimes after vaccination or after infection. N.C. (open rhomboid); SIM BCG/Ad85A inverted triangle; SIM BCG/BCG (open triangle); BCG e.b. (open square); BCG s.c. (open circle). Error bars represent the standard error of the mean (SEM). Data were analysed using a using a Kruskal-Wallis test with Dunn’s multiple column post-test comparison.