Yeast-containing feed additive alters gene expression profiles associated with innate immunity in whole blood of a rodent model

• Published in: Innate immunity (London, England) Vol. 22; no. 4; pp. 249 - 256
• Main Authors: Branson, Jennifer A, McLean, Derek J, Forsberg, Neil E, Bobe, Gerd
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.05.2016
• Subjects: Adaptive Immunity - genetics; Animal Feed - microbiology; Animals; Animals, Inbred Strains; Antigens, CD1d - genetics; Antigens, CD1d - metabolism; B7-1 Antigen - genetics; B7-1 Antigen - metabolism; Blood Cells - immunology; Cattle; Diet; Food Additives - administration & dosage; Immunity, Innate - genetics; Male; Mitogen-Activated Protein Kinase 8 - genetics; Mitogen-Activated Protein Kinase 8 - metabolism; Nod2 Signaling Adaptor Protein - genetics; Nod2 Signaling Adaptor Protein - metabolism; Rats; Ruminantia; Toll-Like Receptor 1 - genetics; Toll-Like Receptor 1 - metabolism; Toll-Like Receptor 2 - genetics; Toll-Like Receptor 2 - metabolism; Transcriptome; Up-Regulation; Yeasts - immunology; Bacterial recognition; feed supplement; yeast cell wall; innate immunity
• ISSN: 1753-4259; 1753-4267
• DOI: 10.1177/1753425916640326

Feeding a yeast-containing additive (YCA; OmniGen-AF) improves immune responses in ruminant livestock and reduces subsequent production losses. The objective was to identify molecular pathways by which dietary YCA may modify immune responses using a rodent model. Thirty-seven healthy, unchallenged CD rats received a diet containing 0 (control; n = 5, only 28 d), 0.5% (n = 15) or 1% (n = 17) YCA for 7 (n = 4/group), 14 (n = 3 or 4/group), 21 (n = 3 or 4/group) or 28 (n = 5/group) d. At the end of the feeding periods, whole blood was collected and the isolated RNA was analyzed for the expression of 84 genes involved in innate and cell-mediated adaptive immune responses. Three bacterial pattern recognition receptors TLR1 (0.5%: + 2.01; 1%: + 2.38), TLR6 (0.5%: + 2.11; 1%: + 2.34) and NOD2 (0.5%: + 2.32; 1%: + 2.23), two APC surface receptors CD1D1 (0.5%: + 1.75; 1%: + 2.33) and CD80 (0.5%: +2.45; 1%: +3.00), and the cell signaling molecule MAPK8 (0.5%: +1.87; 1%: +2.35) were significantly up-regulated by YCA at both inclusion rates. In conclusion, feeding YCA may potentially increase recognition and responses to bacterial pathogens and T-cell activation and differentiation and thereby maintain health and prevent production losses.