Anti-inflammatory effects of Lactobacillus johnsonii L531 in a pig model of Salmonella Infantis infection involves modulation of CCR6+ T cell responses and ER stress

Abstract

Probiotic pretreatment is an effective non-antibiotic strategy for preventing or controlling Salmonella infections. We found that Lactobacillus johnsonii L531, isolated from the colon of a clinically healthy weaned piglet, effectively prevented infection with Salmonella enterica serovar Infantis in a pig model. Newly weaned piglets were intragastrically administered Lactobacillus johnsonii L531 at 1.0 × 10 10 CFU/day for 1 week before S. Infantis challenge. Pretreatment with L. johnsonii L531 lessened the severity of diarrhea and ileal inflammation in S. Infantis-infected piglets. Lactobacilli were more abundant in the ileum than jejunum after L. johnsonii L531 pretreatment. Treatment with L. johnsonii L531 reduced the abundance of total bacteria in the ileal mucosa and the production of lipocalin 2 in the jejunum of piglets challenged with Salmonella. Both intestinal morphology and transmission electron microscopy results indicated that L. johnsonii L531 alleviated intestinal tissue damage following S. Infantis challenge, especially in the villus and endoplasmic reticulum (ER). ER stress induced by S. Infantis was attenuated by L. johnsonii L531 treatment. The number of CD4 − CCR6 + T cells decreased following S. Infantis challenge, but the percentage of CCR6 − IFNγ + T cells in peripheral blood increased. In intestinal mesenteric lymph nodes, S. Infantis increased the proportion of CCR6 + IFNγ + T cells, whereas L. johnsonii L531 induced an increase in the proportion of CD4 + CCR6 + T cells in response to S. Infantis infection. Our data thus suggest that L. johnsonii L531 contributes to the maintenance of intestinal homeostasis by modulating T-cell responses and ER stress.

Fermented Cottonseed Meal as a Partial Replacement for Soybean Meal Could Improve the Growth Performance, Immunity and Antioxidant Properties, and Nutrient Digestibility by Altering the Gut Microbiota Profile of Weaned Piglets

“…In our study, Firmicutes is the most dominant phyla in ileum and Firmicutes and Bacteroidetes in cecum. Lactobacillus , as a potential probiotic, possesses the resistance to pathogen, anti-inflammatory and antioxidant capacity, and ability to improve of gut microbiota profile ( He et al, 2019 ; Yang et al, 2020 ). Wang et al (2017) has discovered that Lactobacilli and total anaerobic bacteria counts in ceca digesta of birds fed FCSM were improved compared with birds fed CSM on days 21 and 42.…”

Lactobacillus johnsonii L531 Alleviates the Damage Caused by Salmonella Typhimurium via Inhibiting TLR4, NF-κB, and NLRP3 Inflammasome Signaling Pathways

“…For bacterial infections, IPEC-J2 Cells were seeded in 6-well (3 × 10 5 cells/well) culture plates (CORNING, NY, USA) under four groups/conditions: (i) medium alone (donated CN); (ii) L. johnsonii L531 pre-incubation (multiplicity of infection, MOI = 3) for 3 h prior to exposure to S. Typhimurium (MOI = 15) (donated LS); (iii) S. Typhimurium alone (MOI = 15) (donated ST), or (iv) incubation with L. johnsonii L531 (MOI = 3) (donated L531) [ 7 ].…”

“…Studies proved that certain strains of Lactobacillus johnsonii exhibited anti-inflammatory properties and attenuated systemic pro-inflammatory immune responses [ 6 ]. Our previous experiments proved that Lactobacillus johnsonii L531 ( L. johnsonii L531) reduced pathogen load and intestinal inflammation in piglets challenged by Salmonella Infantis [ 7 ]. However, the exact mechanism by which L. johnsonii L531 protects the host against intestinal pathogens remains to be further elucidated.…”

The impact of probiotics on gut health via alternation of immune status of monogastric animals

“…For example, changes in the intestinal morphology caused by inflammation will destroy the digestion and absorption of nutrients and the immune function of the intestinal mucosa ( Willing and Van Kessel, 2009 ). The intestinal-morphology results of Salmonella infantis challenge after intragastric administration with Lactobacillus johnsonii L531 for a week showed that L. johnsonii L531 reduced the damage of S. infantis to intestinal villi and the endoplasmic reticulum of piglets ( Yang et al., 2020 ). The evidence suggested that adding 100 mg/kg Clostridium butyricum CGMCC 9386 (5 × 10 10 CFU/g) to 21-d weaned piglets for 28 d could improve growth performance, intestinal morphology, and colonic microflora ( Cao et al., 2019 ).…”