Validation of the dorsal air pouch model to predict and examine immunostimulatory responses in the gut

Abstract

Aims: To validate the use of the air pouch system to predict and examine early immune responses induced by the presumptive probiotics Lactobacillus paracasei subsp. paracasei B112, DC205, DC215 and DC412 strains in the gut mucosa. Methods and Results: Only the DC412 strain interacted strongly with the cells forming the air pouch lining tissue and induced early innate immune responses such as polymorphonuclear (PMN) cell recruitment, phagocytosis and tumour necrosis factor alpha (TNF‐α) production that equal the respective responses induced by the probiotic Lactobacillus acidophilus NCFB 1748. The strains exhibiting strong immunoregulatory activity in the air pouch also interacted strongly with the gut‐associated lymphoid tissue (GALT). The strain DC412 exerts its effect on the intestine through stimulation of Toll‐like receptor (TLR)2/TLR4‐mediated signalling events leading to secretion of a certain profile of cytokines in which gamma interferon (IFN‐γ), TNF‐α, interleukin (IL)‐6 and IL‐10 are included. The probiotic Lact. acidophilus NCFB 1748 induces the same cytokine profile in addition to IL‐12B, and this response is potentially mediated by the synergy of TLR2 and TLR9. Conclusion: The strain DC412 possesses the in vitro and in vivo characteristics of a probiotic micro‐organism. Significance and Impact of the Study: The dorsal mouse or rat air pouch may be used as an alternative and rapid method for the initial discrimination and selection of potential probiotic Lactobacillus strains.

Gluten induces coeliac-like disease in sensitised mice involving IgA, CD71 and transglutaminase 2 interactions that are prevented by probiotics

“…Saccharomyces Boulardii KK1 Strain, a Presumptive Probiotic, Improves Gluten-Induced Enteropathy Because probiotics have been shown to hydrolyse gliadin in vitro, 16 we examined whether presumptive probiotics with established immunoregulatory activity 14,15 have an effect in vivo in the gluten-induced mouse model for CD. The hydrolytic activity of L. paracasei DC412, DC205 or S. boulardii KK1 strains was first verified in vitro by preparing wheat flour fermentation in the presence of these strains.…”

“…14 The sections were stained with hematoxylin and eosin and viewed under regular light microscopy. The villus height/crypt depth (V:C) ratios were obtained from linear measurements of five villus heights in each sample, divided by the corresponding crypt depths as described.…”

“…Indirect immunofluorescence was used to identify the cells producing cytokines and inflammatory mediators by using specific antibodies against mouse IFN-g, TNF-a, IL-10 (R&D Systems, Minneapolis, MN, USA), IL-12B, IL-15, COX-1 and COX-2 (Santa Cruz Biotechnology). 14 The number of positive cells was counted in 10 randomly chosen fields, and an average for each mouse was considered for statistical analysis.…”

“…All lactobacilli were stored at À801C in MRS broth with 25% glycerol, and KK1 cultures were maintained at 41C in a YEGP agar slope. 14,15 Yeast or lactobacilli were harvested at 18-24 h of culturing and resuspended at the appropriate concentration (CFU/ml) according to the McFarland standard.…”

An inulin-based dressing emulsion as a potential probiotic food carrier

“…Also, very recently, L. paracasei subsp. paracasei DC412 has been demonstrated to possess the in vitro and in vivo characteristics of a probiotic micro-organism (Kourelis et al, 2010). Response surface methodology (RSM) was the main tool for achieving this goal.…”