Targeting Cattle-Borne Zoonoses and Cattle Pathogens Using a Novel Trypanosomatid-Based Delivery System
(A) An immunofluorescence image of Trypanosoma theileri stained with antibody to T. brucei alpha tubulin; the kinetoplast and nuclear DNA is stained with DAPI (blue). (B) Schematic representation of the integration of an expression cassette into the SSU rRNA locus of the T. theileri genome by homologous recombination. Read-through transcription drives expression from the integrated cassette. (C) Expression vectors used to assay CAT protein expression in T. theileri, this being as an unmodified protein (“Native”) or modified for secretion (“N-BiP”) or surface expression (“N-BiP-GPI”). For the N-BiP and N-BiP-GPI fusions, two gene copies were inserted in tandem to improve overall expression, these being separated by the T. theileri beta-alpha tubulin intergenic region. The respective distribution of CAT protein to the cell pellet or extracellular milieu is indicated on the right hand side, this being quantitated by CAT ELISA assay.