DAKO Corporation used to sell a rabbit pAb to Mycobacterium paratuberculosis that I used to immunostained Johne's disease tissues.  Unfortunately, they no longer sell this antibody.  However, it has been my experience that most antibodies to mycobacterial antigens are not strain specific; therefore, other anti-mycobacteria antibodies may be effective in labeling the organisms in your specimens. We currently use DAKO's rabbit anti-Mycobacterium bovis (BCG) to label mycobacteria in our human specimens.  It is extremely sensitive for detecting mycobacteria in tissues, but not specific and, as such, immunoreactivity should be confirmed with another method (e.g. AFB or molecular testing).

R. Cartun