LE3 .A278 2007

2007

Shutler, Dave

Acadia University

Bachelor of Science

Masters

Biology

Biology

Cells of the human mucosal epithelia have been found capable of functions previously thought exclusive to the cells of the immune system. These include the ability to secrete cytokines, express costimulatory molecules and act as Antigen Presenting Cells. Certain pathological conditions result from an oversecretion of proinflammatory cytokines including IL-8 and IL-6. While probiotic Lactic Acid Bacteria (LAB) have been shown to interact with cells of the immune system as well as Intestinal Epithelial Cells (IEC) on a cellular level to modulate the immune response, their interactions with other epithelial cells types such as oral keratinocytes, have received little attention. We analysed the ability of 3 strains of probiotic LAB ('L. rhamnosus' RO-011 and RO-029 and 'L. helveticus' RO-052) to modulate cytokine production by human intestinal and oral epithelial cell tines, examining the effects on constitutive pro-inflammatory cytokine production as well as cytokine induction by different pathogens ('Helicobacter pylori, Salmonella typhimurium' and Enteropathogenic 'E. coli'). LAB strains RO-011 and RO-052 down-regulated constitutive IL-8 production by both IEC and oral keratinocytes. These strains also down regulated IL-8 production induced by mucosal pathogens. Strain RO-049 also significantly down-regulated constitutive IL-6 production by oral keratinocytes. Interestingly, strain RO-011 was able to induce increased production of the anti-inflammatory cytokine, IL-10 by oral keratinocytes (TUUJA). This suggests that ' L. rhamnosus' and 'L. acidophilus' are able to significantly modulate the oral and intestinal immune response through IL-8 and IL-6 down regulation and potential up regulation of IL-10 production. This may have implications for the future treatment of inflammatory diseases of the oral cavity and GI tract. Preliminary examination of the degree to which probiotic LAB can interfere with pathogen binding to oral keratinocytes suggest that further study of these abilities is warranted, as is study of the ability of probiotic LAB to modulate costimulatory molecule expression in IEC.

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https://scholar.acadiau.ca/islandora/object/theses:2725