Comparative effect of the adjuvant capacity ofLactobacillus caseiand lipopolysaccharide on the intestinal secretory antibody response and resistance toSalmonellainfection in mice

Abstract

1995) Comparative effect of the adjuvant capacity of Lactobacillus casei and lipopolysaccharide on the intestinal secretory antibody response and resistance to Salmonella infection in mice, Food and Agricultural Immunology, 7:3, 283-294, A comparative study was carried out to determine the effect of Lactobacillus casei lipopolysaccharide (LPS) and a mixture of L. casei plus LPS used as oral adjuvants on the increase of mucosal immunity. The ability of these substances to protect against enteric infection was also studied. It was demonstrated that treatment with viable L. casei mixed with LPS and administered for 2 days was more effective than L. casei or LPS alone in increasing secretory IgA (S-IgA) levels, the number of IgA-producing cells and the total number of T-lymphocytes. These effects were not observed when non-viable L. casei were used with LPS. The study examined the duration of stimulation with L. casei, LPS or a mixture. S-IgA levels were measured and the effect of boosting (carried out at 15 and 30 days post-priming with a single dose) against infection with Salmonella typhimurium was determined. L. casei or LPS alone were demonstrated to maintain the IgA levels determined in intestinal fluid for 3 days. Such levels increased with boosting, along with the number of IgA-producing cells, thus favouring protection against S. typhimurium infection. When L. casei plus LPS were used, the IgA levels were maintained for 7 days. When boosting was effected with the same mixture, results similar to those obtained with L. casei were observed. No side-effects (hepato and/or splenomegaly) were observed in any case, although the mixture of L. casei plus LPS was shown to induce an increase in polymorphonuclear cells in histological studies. This failed to occur when L. casei or LPS were administered separately. However, the mixture was an effective immunopotentiator in the prevention of Salmonella infection due to the association of the two adjuvant substances. The authors believe that viable L. casei, by either itself or associated with LPS (the most important structure of the Gram-negative enteropathogen cell wall), administered at adequate doses, might act as a useful adjuvant in the mucosa by protecting the host from infections.

Live and heat-inactivated lactobacilli from feces inhibit Salmonella typhi and Escherichia coli adherence to caco-2 cells

“…It was reported that orally administered nonviable probiotics are less effective in modulating the immune system than viable probiotics due to their lower ability to bind to the intestinal mucosa (Perdigon et al 1995;Kato et al 1994), suggesting that probiotics should be viable in order to elicit beneficial health effects. However literature overview indicates that although viable probiotics have more documented health effects than nonviable probiotics, the latter are not without effect (Ouwehand and Salminen 1998;Čepeljnik et al 2007).…”

Differential Effect of Lactobacillus johnsonii BFE 6128 on Expression of Genes Related to TLR Pathways and Innate Immunity in Intestinal Epithelial Cells

“…Probiotics represent an economical alternative for boosting immune defenses and/or diminishing the severity of bacterial diarrhea. In several rodent studies, probiotics protected against infection with Salmonella Typhimurium [2,18,19]. Prolonged survival rates and diminished translocation of the pathogen to extraintestinal sites were correlated with a stimulation of adaptive immunity, clearly indicated by enhanced IgA production, a mucosal defense antibody [7].…”

Milk fermented by Lactobacillus helveticus R389 and its non-bacterial fraction confer enhanced protection against Salmonella enteritidis serovar Typhimurium infection in mice

“…Shu et al (2000) and Gill et al (2001) reported that selected probiotic strains orally administered to mice conferred enhanced resistance against Salmonella enteritidis serovar Typhimurium infection. In our laboratory, it was demonstrated that the oral administration of milk fermented by Lactobacillus casei and Lactobacillus acidophilus (Perdigo´n et al, 1990), yoghurt (Perdigo´n et al, 1991) or its microflora and the strain L. casei CRL 431 itself (Perdigo´n et al, 1993(Perdigo´n et al, , 1995 were effective in the prevention of S. Typhimurium infection in conventional and in malnourished/ re-nourished mice (Gauffin-Cano and Perdigo´n, 2003). Not only fermented milks or lactic acid bacteria were reported to activate immune cells and to confer enhanced protection against enteropathogens.…”