Emerging technologies and their applications in interactions between nutrition and immunity to gastrointestinal parasites in sheep.

SUMMARY Despite the plethora of evidence on the consequences of host nutrition on their immune responses to gastrointestinal parasites, the identity of molecules and mechanisms that drive the manifestations of immunity under nutrient abundance are not yet known. This is partly due to limitations of the methodologies employed to date that have failed to give comprehensive answers. The great advancements in the technological front over the past few years have opened a window of opportunity to identify these effector molecules, to explore both the mechanisms and cellular pathways and to evaluate their importance in the immune response to parasites. The aim of this paper is to present some of the novel, high-throughput technologies that are currently available in immunology and to explore their use in advancing our knowledge in interactions between nutrition and immunity to nematode parasites, with special reference to sheep. In the first part, we introduce the technologies and we discuss advantages and pitfalls of their use. We bring in successful examples of how their employment advanced knowledge and improved our understanding of the mechanisms that regulate immune responses to pathogens (both micro- and macroparasites). In the second part, we focus on the impact of nutrition on the immune response to parasites, and explore how these technologies can be used to advance our knowledge of immunonutritional interactions. We use as our starting point well-established models that have been successfully used to investigate the consequences of nutrition on the manifestations of immunity to parasites, which we further consider in the context of the novel technologies. We conclude by emphasizing the great potential of the described methodologies in unravelling the complex interactions between nutrition and immunity, but we also recommend caution when interpreting the outcomes.