Lactobacillus paracasei feeding improves immune control of influenza infection in mice

• Published in: PloS one 2017-09, Vol.12 (9), p.e0184976-e0184976
• Main Authors: Belkacem, Nouria, Serafini, Nicolas, Wheeler, Richard, Derrien, Muriel, Boucinha, Lilia, Couesnon, Aurélie, Cerf-Bensussan, Nadine, Gomperts Boneca, Ivo, Di Santo, James P, Taha, Muhamed-Kkeir, Bourdet-Sicard, Raphaëlle
• Format: Article
• Language: English
• Subjects: Accumulation; Adults; Analysis; Animals; Bacteria; Bacterial infections; Bioinformatics; Biology and Life Sciences; Care and treatment; Children; Colony Count, Microbial; Control; Development and progression; Feeding; Female; Food and Nutrition; Gene expression; Genomes; Homeostasis; Human health and pathology; Immune clearance; Immune response; Immunity; Immunity, Cellular - immunology; Immunomodulation; Infections; Infectious diseases; Inflammation; Influenza; Intestinal microflora; Intestine; Laboratories; Lactobacilli; Lactobacillus; Lactobacillus paracasei; Lactobacillus paracasei - physiology; Life Sciences; Lungs; Medicine and Health Sciences; Methods; Mice; Mice, Inbred BALB C; Modulators; Morbidity; Multivariate analysis; Myeloid cells; Orthomyxoviridae - immunology; Orthomyxoviridae Infections - immunology; Orthomyxoviridae Infections - microbiology; Orthomyxoviridae Infections - prevention & control; Peptidoglycans; Physical Sciences; Physiological aspects; Probiotics; Probiotics - administration & dosage; Research and Analysis Methods; Respiratory tract; Respiratory tract diseases; Respiratory Tract Infections - immunology; Respiratory Tract Infections - microbiology; Respiratory Tract Infections - prevention & control; Viral infections
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0184976

Respiratory tract infections such as flu cause severe morbidity and mortality and are among the leading causes of death in children and adults worldwide. Commensal microbiota is critical for orchestrating tissue homeostasis and immunity in the intestine. Probiotics represent an interesting source of immune modulators and several clinical studies have addressed the potential beneficial effects of probiotics against respiratory infections. Therefore, we have investigated the mechanisms of protection conferred by L. paracasei CNCM I-1518 strain in a mouse model of influenza infection. Notably, local myeloid cells accumulation is generated in the lungs after seven days feeding with L. paracasei prior to viral infection. L. paracasei-fed mice showed reduced susceptibility to the influenza infection, associated with less accumulation of inflammatory cells in the lungs, faster viral clearance and general health improvement. Interestingly, Allobaculum was significantly increased in L. paracasei-fed mice 7 days after influenza infection, even if the gut microbiota composition was not altered overall. L. paracasei-purified peptidoglycan partially recapitulated the protective phenotype observed with the entire bacteria. Collectively, our results demonstrate that oral consumption of L. paracasei CNCM I-1518 modulates lung immunity was associated with an improved control of influenza infection. These results further extend the beneficial role for certain lactobacilli to alleviate the burden of respiratory tract infections.