Monoassociation with probiotic Lactobacillus delbrueckii UFV-H2b20 stimulates the immune system and protects germfree mice against Listeria monocytogenes infection

Abstract

In the present study, we investigated the protective effects of Lactobacillus delbrueckii UFV-H2b20 on the resistance to Listeria monocytogenes infection in gnotobiotic mice. Germfree mice or monoassociated mice were infected with L. monocytogenes, and the microbiological and immunological responses were evaluated after 1, 3, and 5 days of infection. Monoassociation with L. delbrueckii was capable of protecting mice against death caused by L. monocytogenes and induced a faster clearance of the bacteria in the liver, spleen, and peritoneal cavity at days 1, 3, and 5 post-infection. Also, monoassociated mice displayed less liver injury than germfree mice. The production of TNF-α in the serum, peritoneal cavity, and gut was augmented in monoassociated mice. Likewise, the levels of IFN-γ found on supernatants of spleen cells cultures were higher after the monoassociation. In addition, increased production of nitric oxide in peritoneal cell cultures supernatants and in serum was observed in mice that received L. delbrueckii. The monoassociation with L. delbrueckii induced higher production of IL-10 in the mucosal immune system. We conclude that monoassociation with L. delbrueckii UFV-H2b20 protects mice from death caused by L. monocytogenes infection by favoring effector responses while preventing their immunopathological consequences.

Regulation of Bacterial Pathogenesis by Intestinal Short-Chain Fatty Acids

“…Work published as early as 1979 revealed that GF animals show increased susceptibility to Lm colonization and that the intestinal microbiota, introduced either individually or as a community, is capable of decreasing Lm colonization of GF mice (Archambaud et al, 2012; Bambirra et al, 2007; dos Santos et al, 2011; Nakamura et al, 2012; Vieira et al, 2008; Zachar & Savage, 1979) and rats (Czuprynski & Balish, 1981). Although these studies do not provide clear mechanisms for colonization resistance, they nevertheless demonstrate a functional requirement for the gut microbiota in protection against L. monocytogenes infection.…”

Adapting to environmental stresses: the role of the microbiota in controlling innate immunity and behavioral responses

“…Indeed, studies have found that GF mice are more susceptible to infection by Leishmania major (39) or Trypanosoma cruzi (40). In addition, infection by the Gram‐positive intracellular pathogen Listeria monocytogenes resulted in decreased bacterial clearance in GF animals compared with colonized animals (41). We have also found that there is limited production of TNF‐α and CXCL‐1 and reduction of neutrophil influx after pulmonary infection with Klebsiella pneumoniae (Fagundes, Teixeira, and Souza, unpublished data).…”

In vitroadhesion and anti-inflammatory properties of nativeLactobacillus fermentumandLactobacillus delbrueckiispp.

“…Lactobacillus delbrueckii on the other hand is a pronounced dairy starter culture recently reported for its probiotic traits and immunological effects in vivo (Dos Santos et al . ; Santos et al . ; Archer et al .…”