Figure 9.
Effect of CD4 T cells depletion on the ability of Lacticaseibacillus rhamnosus CRL1505 to modulate the respiratory immune response triggered by Respiratory Syncytial Virus (RSV) infection. Infant mice were orally treated with L. rhamnosus CRL1505 (108 cell/mouse/day) during five consecutive days. On days 1, 3, and 5 mice were injected intraperitoneally with purified anti-CD4 blocking antibodies or isotype control antibodies. One day after the last lactobacilli administration, alveolar macrophages were isolated from infant mice, cultured, and challenged in vitro with RSV. Twelve hours after the viral infection, the expression of IFNAR1, Mx2, OAS1, and IFITM3 genes were evaluated by qRT-PCR. Twenty-four hours after the viral infection, the levels of interferon IFN-β, IFN-γ, interleukin (IL)-6, and IL-27 were evaluated on alveolar macrophages supernatants. The results represent data from three independent experiments. Asterisks indicate significant differences when compared to the isotype control group. *P < 0.05, **P < 0.01.