The increased expression of CCL17, DEFB10 and matrix metalloproteinase MMP12 with the decreased expression of bactericidal permeability increasing protein BPI, CD164 and IL5 receptor IL5RA can differentiate M. bovis AF2122/97 infected animals from M. tuberculosis H37Rv infected animals at both day 14 and day 42 post infection upon PPD-B stimulation. The gene discussed is MMP12; the disease is infection.