Heat-killed Lactobacillus gasseri TMC0356 protects mice against influenza virus infection by stimulating gut and respiratory immune responses

Abstract

This study investigated whether heat-killed Lactobacillus protects host animal against influenza virus infection and stimulates their immunity. Heat-killed Lactobacillus gasseri TMC0356 was orally administered to BALB/c mice for 19 days; the mice were intranasally infected with Flu A/PR/8/34 (H1N1) on day 14, and clinical symptoms were monitored. After 6 days, the mice were sacrificed, and pulmonary virus titres were determined. Splenic activation of natural killer (NK) cells and the mRNA expression of cytokines and other immune molecules in the lung and Peyer's patch (PP) were analysed. Clinical symptom scores of mice orally fed TMC0356 ameliorated significantly (P < 0.01); their pulmonary virus titres decreased significantly compared with those of control mice (P < 0.05); their mRNA expression of interleukin (IL)-12, IL-15 and IL-21 in PP and the pulmonary mRNA expression of IFN-γ, TNF, IL-12a, IL-12rbl, IL-2rb and perforin 1 increased significantly (P < 0.05). Oral administration of heat-killed lactobacilli may protect against influenza virus infection by stimulating local and systemic immune responses. Cellular components of lactobacilli may be pivotal in protecting against viral infection by enhancing gut and respiratory immune responses.

Purified cell wall from the probiotic bacterium Lactobacillus gasseri activates systemic inflammation and, at higher doses, produces lethality in a rat model

“…Heat-killed L. gasseri administered orally in Balb/c mice activated splenic natural killer cells and increased pulmonary inflammatory cytokine (TNF-α, INF-γ, and IL-12) mRNA expression [21,26]. In this latter study, immune stimulation by L. gasseri was actually protective during influenza viral infection [26]. This may have been because L. gasseri remained compartmentalized in the intestinal space.…”

“…Whole L. gasseri bacteria or cell-wall extracts alone stimulated inflammatory cytokine production, including IL-1β, IL-6, IL-10, TNF-α, MCP-1, MIP-1α, or GM-CSF, or NO levels from either murine J774.1 or RAW264.7 macrophages or human myeloid dendritic cells [16,21]. Heat-killed L. gasseri administered orally in Balb/c mice activated splenic natural killer cells and increased pulmonary inflammatory cytokine (TNF-α, INF-γ, and IL-12) mRNA expression [21,26]. In this latter study, immune stimulation by L. gasseri was actually protective during influenza viral infection [26].…”

Modulation of the spleen transcriptome in domestic turkey (Meleagris gallopavo) in response to aflatoxin B1 and probiotics

“…For example, probiotics in the context of aflatoxicosis down-regulated B2M, PRF1, and STAT1. Contrary to expression changes in the turkey, dietary exposure to Lactobacillus in mammals is generally considered to be immunostimulatory and in mice increases the expression of B2M and TAP2 in spleen tissue (Fukui et al 2013(Fukui et al , 2014 and of PRF1 in the lung (Kawase et al 2011). In human macrophages, L. rhamnosus GG also enhanced nuclear translocation and DNA binding by STAT1 (Miettinen et al 2000;Trapecar et al 2014).…”

Immunomodulatory and Therapeutic Activity of Bifido- And Lactobacteria in Children With Allergic Diseases and Frequent Respiratory Tract Infections

“…Так, в исследовании in vitro было установ-лено, что лактобактерии значительно уменьшают спо-собность вируса простого герпеса к размножению [22]. Было показано, что назначение L. casei per os мышам оказывало лечебный и профилактический эффект при инфицировании их вирусом гриппа H1N1 [23,24].…”