Flavanol-Rich Cocoa Powder Interacts with Lactobacillus rhamnossus LGG to Alter the Antibody Response to Infection with the Parasitic Nematode Ascaris suum

Abstract

Consumption of the probiotic bacteria <i>Lactobacillus</i><i>rhamnosus</i><i>LGG</i> and flavanol-rich cocoa have purported immune modulating effects. This study compared the host response to infection with <i>Ascaris suum</i> in three-month-old pigs fed a standard growth diet supplemented with a vehicle control: LGG, cocoa powder (CP) or LGG + CP. Pigs were inoculated with infective <i>A</i>. <i>suum</i> eggs during Week 5 of dietary treatment and euthanized 17 days later. <i>Lactobacillus</i> abundance was increased in pigs fed LGG or LGG + CP. Specific anti-<i>A</i>. <i>suum</i> IgG2 antibodies were decreased (<i>p</i> < 0.05) in LGG + CP-fed pigs compared to pigs fed CP alone. Pigs fed LGG had significantly reduced expression (<i>p</i> < 0.05) of Eosinophil peroxidase (<i>EPX)</i>, Interleukin 13 (<i>IL-13)</i>, Eotaxin 3 (<i>CCL26)</i>, Toll-like receptor 2 (<i>TLR2</i>), TLR4, and TLR9 and Interleukin-1Beta (<i>IL1B</i>) in the tracheal-bronchial lymph node (TBLN) independent of CP treatment. These results suggested that feeding LGG significantly reduced the localized prototypical Th2-related markers of infection with <i>A</i>. <i>suum</i> in the TBLN. Although feeding CP does not appear to affect the <i>A</i>. <i>suum-</i>induced Th2-associated cytokine response, feeding LGG + CP reduced anti-<i>A</i>. <i>suum</i> antibodies and delayed intestinal expulsion of parasitic larvae from the intestine.