AUTHOR=Soutter Francesca , Werling Dirk , Nolan Matthew , Küster Tatiana , Attree Elizabeth , Marugán-Hernández Virginia , Kim Sungwon , Tomley Fiona M. , Blake Damer P. 

TITLE=A Novel Whole Yeast-Based Subunit Oral Vaccine Against Eimeria tenella in Chickens

JOURNAL=Frontiers in Immunology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2022.809711

DOI=10.3389/fimmu.2022.809711

ISSN=1664-3224

ABSTRACT=<p>Cheap, easy-to-produce oral vaccines are needed for control of coccidiosis in chickens to reduce the impact of this disease on welfare and economic performance. <italic>Saccharomyces cerevisiae</italic> yeast expressing three <italic>Eimeria tenella</italic> antigens were developed and delivered as heat-killed, freeze-dried whole yeast oral vaccines to chickens in four separate studies. After vaccination, <italic>E. tenella</italic> replication was reduced following low dose challenge (250 oocysts) in Hy-Line Brown layer chickens (p&lt;0.01). Similarly, caecal lesion score was reduced in Hy-Line Brown layer chickens vaccinated using a mixture of S. cerevisiae expressing EtAMA1, EtIMP1 and EtMIC3 following pathogenic-level challenge (4,000 <italic>E. tenella</italic> oocysts; p&lt;0.01). Mean body weight gain post-challenge with 15,000 <italic>E. tenella</italic> oocysts was significantly increased in vaccinated Cobb500 broiler chickens compared to mock-vaccinated controls (p&lt;0.01). Thus, inactivated recombinant yeast vaccines offer cost-effective and scalable opportunities for control of coccidiosis, with relevance to broiler production and chickens reared in low-and middle-income countries (LMICs).</p>