AUTHOR=Blohmke Christoph J. , Hill Jennifer , Darton Thomas C. , Carvalho-Burger Matheus , Eustace Andrew , Jones Claire , Schreiber Fernanda , Goodier Martin R. , Dougan Gordon , Nakaya Helder I. , Pollard Andrew J. 

TITLE=Induction of Cell Cycle and NK Cell Responses by Live-Attenuated Oral Vaccines against Typhoid Fever

JOURNAL=Frontiers in Immunology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2017.01276

DOI=10.3389/fimmu.2017.01276

ISSN=1664-3224

ABSTRACT=<p>The mechanisms by which oral, live-attenuated vaccines protect against typhoid fever are poorly understood. Here, we analyze transcriptional responses after vaccination with Ty21a or vaccine candidate, M01ZH09. Alterations in response profiles were related to vaccine-induced immune responses and subsequent outcome after wild-type <italic>Salmonella</italic> Typhi challenge. Despite broad genetic similarity, we detected differences in transcriptional responses to each vaccine. Seven days after M01ZH09 vaccination, marked cell cycle activation was identified and associated with humoral immunogenicity. By contrast, vaccination with Ty21a was associated with NK cell activity and validated in peripheral blood mononuclear cell stimulation assays confirming superior induction of an NK cell response. Moreover, transcriptional signatures of amino acid metabolism in Ty21a recipients were associated with protection against infection, including increased incubation time and decreased severity. Our data provide detailed insight into molecular immune responses to typhoid vaccines, which could aid the rational design of improved oral, live-attenuated vaccines against enteric pathogens.</p>