PBMCs of healthy blood donors were stimulated with whole bacteria, recombinant Bp proteins and control stimulators for 42 hours in vitro and IFN-γ secreting cells were enumerated by ELISPOT. IFN-γ spot forming cells (SFC) per 1×106 PBMCs in response to (A) control stimulators including medium alone (M), cytokines (1 µg/ml IL-12 plus IL-15), 1.25 µg/ml PHA, 2 µg/ml pooled viral peptides (CEF) and 1 µg/ml non related protein of F. tularensis (FT) and (B) IFN-γ responses to 3×106 CFU/ml heat killed B. pseudomallei (hkBp), 1 µg/ml ABC transporter proteins of B. pseudomallei (LolC, OppA and PotF). IFN-γ spots were enumerated in the absence (closed circles) and presence (crossed) of 0.3 µg/ml cyclosporin A (CsA). Horizontal lines represent the mean value of each group, *** P<0.0001, ns-non statistical significance (paired t-test).