DIFFERENTIAL EXPRESSION OF CELL SURFACE-ASSOCIATED AND DENSE GRANULE-ASSOCIATED NEOSPORA-CANINUM PROTEINS IN TACHYZOITES AND BRADYZOITES

Morphologically, the tachyzoites and the tissue cysts of Neospora cani num are difficult to distinguish from those of other cyst-forming apic omplexan parasites such as Toxoplasma gondii. Several stage-specific a ntigens have been identified in T. gondii tachyzoites and bradyzoites, and respective antibodies are useful tools for discriminating between the 2 stages during tachyzoite-bradyzoite interconversion in T. gondi i infections. Whereas several cell surface- and dense granule-associat ed proteins have been identified and characterized in N. caninum tachy zoites, not much is known about antigenic components expressed in N. c aninum bradyzoites. In this study, the differential expression of the 2 N. caninum surface proteins Nc-p43 and Nc-p36 and the dense granule protein Nc-p33 (NCDG1) within tachyzoites and bradyzoites of N. caninu m has been investigated.