The project will measure mucosal and hepatic-derived immunity in swine with different vitamin A status to yield potential biomarkers of human nutrient/disease interactions. This will be implemented by 1) development of high throughput processing and analysis of porcine gene expression using real-time PCR and microarrays, 2) evaluation of the primary immune responses to parasitic nematodes in pigs given retinoic acid (ATRA), 3) evaluation of the primary or secondary immune responses to parasitic nematodes in pigs with different vitamin A status, and 4) evaluation of the effect of ATRA or vitamin A status on the development of an allergic disease.
Approach: Rapid and sensitive assays are needed to identify nutritionally relevant biomarkers of immune status in people and to evaluate the effects of diet on immune function. Vitamin A (VA) deficiency affects 140-250 million people worldwide. Epidemiological and clinical trials demonstrate an increased risk of infectious disease morbidity and mortality even in the absence of overt signs or severe declines in plasma VA. Parasitic infections affect the economic efficiency of swine production and impact human health worldwide. Both humans and pigs are infected with species of nematodes that induce similar immune responses. Studies in rodents, pigs and humans indicate that immune function is responsive to changes in VA nutritional status. Technologies such as magnetic bead and flow cytometric cell sorting, laser capture micro dissection (LCM), real-time PCR, microarrays and aRNA amplification can be applied to all these host species and allow for the isolation of specific populations of cells along with whole tissue sections that can be extracted to provide RNA for genomic array analysis. Developments of new technologies to identify biomarkers of immune status that are responsive to changes in nutrition are needed to improve appropriate nutrient interactions with immune responses that are beneficial to the host.