Roadmap for nematode vaccine development

Development of an affordable stable expression system for large-scale production of recombinant protein/glycoproteins

• That expressed antigens have the correct conformation and glycosylation to induce protective immunity.
• Generation of stable genetically modified organisms allowing large scale production.
• Different antigens may require different expression systems

• Various cell line expression systems – bacteria, insect, yeast, mammalian, parasite or plant-derived.
• Epitope mapping to identify minimum required peptides for immune stimulation.
• Concatamerisation of minimum required epitopes for expression

• Identity of the protective antigens for the different parasite species.
• Knowledge of the importance of conformation and secondary modifications (e.g. glycosylation) for protective properties of vaccine antigens.
• Freedom to operate and/or licensing of vectors and expression cell lines for commercial exploitation

• The H. contortus ES antigen Hc23 expressed in E. coli protected lambs against experimental challenge (Alunda lab, Madrid)
• A vaccine cocktail of eight recombinant T. circumcincta antigens expressed in E.coli and P. pastoris protected lambs and ewes against a trickle challenge (Nisbet et al., 2013, 2016.)
• C. elegans expression system (Britton et al., Glasgow), active proteases (H11) but non-protective vs. Haemonchus
• Ostertagia and Cooperia ASPs, recombinant antigens did not protect