Figure 5.

Immunomodulatory capacities of the mucus-binding factor knockout Lacticaseibacillus rhamnosus CRL1505 (ΔmbfCRL1505) strain on the intestinal innate antiviral immune response triggered by the activation of the Toll-like receptor 3 (TLR3). Balb/c mice (6-week-old) were orally treated with the wild-type L. rhamnosus CRL1505 or ΔmbfCRL1505 strains (10⁸ cells/mouse) for two consecutive days prior to the intraperitoneal injection of the TLR3 agonist poly(I:C). Untreated mice challenged with poly(I:C) were used as controls. The numbers of CD3⁺NK1.1⁺ and CD3⁺CD8αα⁺ intraepithelial lymphocytes (IELs), the levels of intestinal interferon (IFN)-β, IFN-γ, interleukin (IL)-6, tumor necrosis factor (TNF)-α and IL-15 and the level of serum IL-15 were determined 2 days after the poly(I:C) challenge. The results represent data from three independent experiments. Asterisks indicate significant differences when compared to the poly(I:C) control group (** p < 0.01).