Enterococcus faecium SF68 Enhances the Immune Response to Giardia intestinalis in Mice

Abstract

This study shows the ability of Enterococcus faecium strain SF68 to antagonize Giardia intestinalis infection in mice. Oral administration of Enterococcus faecium strain SF68 starting 10 days prior infection with giardia trophozoites significantly increased the production of specific anti-Giardia intestinal IgA and blood IgG. This humoral response was mirrored at the cellular level by an increased percentage of CD4+ T cells in Peyer’s patches and spleens of SF68-treated mice. The improved specific immune responses at both local and systemic levels correlated with the limitation and control of the infection as revealed by the diminution of the number of active trophozoites in small intestine as well as the shedding of fecal giardia antigens (GSA65 protein) in probiotic-treated animals. The ability of SF68 to stimulate the immune system at both mucosal and systemic level might illustrate a mechanism by which this probiotic antagonize pathogens in vivo. All together the data demonstrate the high potential of strain SF68 to prevent against protozoa involved in intestinal infections.