TY - JOUR

T1 - Bacillus subtilis-597 induces changes in lung pathology and inflammation during influenza A virus infection in pigs

AU - Winther, Katrine

AU - Kristensen, Charlotte

AU - Henriksen, Betina Lyngfeldt

AU - Hansen, Lea Hübertz Birch

AU - Ryt-Hansen, Pia

AU - Vestergaard, Gisle

AU - Skovgaard, Kerstin

AU - Sandvang, Dorthe

AU - Boll, Erik Juncker

AU - Williams, Andrew R.

AU - Larsen, Lars E.

N1 - Publisher Copyright: © 2024 The Authors

PY - 2024

Y1 - 2024

N2 - In recent years, it has become apparent that imbalances in the gastrointestinal system can impact organs beyond the intestine such as the lungs. Given the established ability of probiotics to modulate the immune system by interacting with gastrointestinal cells, our research aimed to investigate whether administering the probiotic strain Bacillus subtilis-597 could mitigate the outcome of influenza virus infection in pigs. Pigs were fed a diet either with or without the probiotic strain B. subtilis-597 for 14 days before being intranasally inoculated with a swine influenza A H1N2 strain (1 C.2 lineage). Throughout the study, we collected fecal samples, blood samples, and nasal swabs to examine viral shedding and immune gene expression. After seven days of infection, the pigs were euthanized, and lung and ileum tissues were collected for gene expression analysis and pathological examination. Our findings indicate that the administration of B. subtilis-597 exhibit potential in reducing lung lesions, possibly attributable to a general suppression of the immune system as indicated by reduced C-reactive protein (CRP) levels in serum, decreased expression of interferon-stimulated genes (ISGs), and localized reduction of the inflammatory marker serum amyloid A (SAA) in ileum tissue. Notably, the immune-modulatory effects of B. subtilis-597 appeared to be unrelated to the gastrointestinal microbiota, as the composition remained unaltered by both the influenza infection and the administration of B. subtilis-597.

AB - In recent years, it has become apparent that imbalances in the gastrointestinal system can impact organs beyond the intestine such as the lungs. Given the established ability of probiotics to modulate the immune system by interacting with gastrointestinal cells, our research aimed to investigate whether administering the probiotic strain Bacillus subtilis-597 could mitigate the outcome of influenza virus infection in pigs. Pigs were fed a diet either with or without the probiotic strain B. subtilis-597 for 14 days before being intranasally inoculated with a swine influenza A H1N2 strain (1 C.2 lineage). Throughout the study, we collected fecal samples, blood samples, and nasal swabs to examine viral shedding and immune gene expression. After seven days of infection, the pigs were euthanized, and lung and ileum tissues were collected for gene expression analysis and pathological examination. Our findings indicate that the administration of B. subtilis-597 exhibit potential in reducing lung lesions, possibly attributable to a general suppression of the immune system as indicated by reduced C-reactive protein (CRP) levels in serum, decreased expression of interferon-stimulated genes (ISGs), and localized reduction of the inflammatory marker serum amyloid A (SAA) in ileum tissue. Notably, the immune-modulatory effects of B. subtilis-597 appeared to be unrelated to the gastrointestinal microbiota, as the composition remained unaltered by both the influenza infection and the administration of B. subtilis-597.

KW - Bacillus subtilis

KW - Influenza A

KW - Innate Immunity

KW - Mucosal Immunology

KW - Pigs

KW - Probiotics

KW - Virus

U2 - 10.1016/j.vetmic.2024.110032

DO - 10.1016/j.vetmic.2024.110032

M3 - Journal article

C2 - 38430715

AN - SCOPUS:85186546769

VL - 291

JO - Veterinary Microbiology

JF - Veterinary Microbiology

SN - 0378-1135

M1 - 110032

ER -