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bioRxiv · 10.1101/699231

CD4+ Th immunogenicity of the Ascaris spp. secreted products

Ebner, F.·Morrison, E.·Bertazzon, M.·Midha, A.·Hartmann, S.·Freund, C.·Álvaro-Benito, M.
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Abstract

Ascaris spp. is a major health problem of humans and animals alike, and understanding the immunogenicity of its antigens is required for developing urgently needed vaccines. The parasite-secreted products represent the most relevant, yet highly complex (>250 proteins) antigens of Ascaris spp. as defining the pathogen-host interplay. We applied an in vitro antigen processing system coupled to quantitative proteomics to identify potential CD4+ Th cell epitopes in Ascaris suum-secreted products. This approach restricts the theoretical list of epitopes, based on affinity prediction, by a factor of [~]1200. More importantly, selection of 2 candidate peptides based on experimental evidence demonstrated the presence of epitope-reactive T cells in Ascaris-specific T cell lines generated from healthy human individuals. Thus, this stringent work pipeline identifies a human haplotype-specific T cell epitope of a major human pathogen. The methodology described represents an easily adaptable platform for characterization of highly complex pathogenic antigens and their MHCII-restriction.

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Ebner, F., Morrison, E., Bertazzon, M., Midha, A., Hartmann, S., Freund, C., Álvaro-Benito, M.. 2019-07-14. CD4+ Th immunogenicity of the Ascaris spp. secreted products. https://doi.org/10.1101/699231

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