|Ledbetter, Tonya - JOHNS HOPKINS, MD|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 30, 2003
Publication Date: May 14, 2003
Citation: Solano Aguilar, G., Ledbetter, T., Dawson, H.D., Schoene, N.W., Urban Jr, J.F. 2003. The effect of dietary probiotic in the immune response of pigs [abstract]. 9th International Symposium on Digestive Physiology in Pigs. 2:69. Technical Abstract: Rigorous scientific testing of claims for functional foods that contain probiotic bacteria for promotion of health and disease prevention is needed. We have developed a pig model to test the effect of probiotics on immune function. Eight, 12-week-old pigs were divided into two groups with four pigs fed daily a capsule containing 10 billion colony forming units (cfu) freeze-dried Lactobacillus rhamnosus GG (LGG) (CAG Functional Foods, Inc) for 26 consecutive days and four other pigs left as non-treated controls. Blood and fecal samples were collected throughout the experiment at days 4, 7, 12, 18 and 25 after initiation of dietary treatment. At the end of the experiment (day 26), pigs were euthanized and tissues from lymph nodes and intestinal sections were collected for 1) cell surface immune phenotypic analysis using flow cytometry; 2) DNA isolation and identification of LGG strain in tissues and fecal samples by Taqman real-time PCR; 3) mRNA gene expression of immune markers (cytokines) by real-time PCR. The results showed that there was no change in the immune phenotype of lymphoid cells isolated from peripheral blood, lymph nodes and intestinal mucosa in pigs treated with LGG compared to non-treated pigs. Results using a specific porcine IFN-Y ELISA demonstrated that cells from LGG-exposed animals were able to produce IFN-Y in response to ConA stimulation, but not cells isolated from unexposed animals. These changes reflect an enhanced Th1-type response, similar to what has been reported for humans treated with LGG. A clear association of the LGG bacteria with intestinal mucosa was demonstrated. Testing probiotic strains in pigs is an excellent model for humans because of comparable immune and intestinal function.