摘要：The expanding knowledge on the systemic influence of the human microbiome suggests that fecal samples are underexploited sources of new beneficial strains for extra-intestinal health. We have recently shown that acetate, a main circulating microbiota-derived molecule, reduces the deleterious effects of pulmonary
Streptococcus pneumoniae and enteric
Salmonella enterica serovar Typhimurium bacterial post-influenza superinfections. Considering the beneficial and broad effects of acetate, we intended to isolate a commensal strain, producing acetate and potentially exploitable in the context of respiratory infections. We designed successive steps to select intestinal commensals that are extremely oxygen-sensitive, cultivable after a freezing process, without a proinflammatory effect on IL-8 induction, and producing acetate. We have identified the
Blautia faecis DSM33383 strain, which decreased the TNFα-induced production of IL-8 by the intestinal epithelial cell line HT-29. The beneficial effect of this bacterial strain was further studied in two preclinical models of post-influenza
Streptococcus pneumoniae (
S.p) and
Salmonella enterica serovar Typhimurium (
S.t) superinfection. The intragastrical administration of
Blautia faecis DSM33383 led to protection in influenza-infected mice suffering from an
S.p. and, to a lesser extent, from an
S.t secondary infection. Altogether, this study showed that
Blautia faecis DSM33383 could be a promising candidate for preventive management of respiratory infectious diseases.
关键词：enBlautia faecisacetatepost-influenzapulmonary and enteric superinfectionanti-inflammatoryextremely oxygen-sensitive probiotics
