Probiotic and postbiotic activity in health and disease: comparison on a novel polarised ex-vivo organ culture model

Abstract

Background and aims Probiotics and their metabolic products, here called postbiotics, have been proposed as food supplements for a healthier intestinal homeostasis, but also as therapeutic aids in inflammatory bowel disease (IBD) with, however, very little clinical benefit. This may be due to the lack of reliable preclinical models for testing the efficacy of different strains. Methods The activity of three probiotic strains of Lactobacillus (or a postbiotic) was analysed and compared with a pathogenic strain of Salmonella on a novel organ culture system of human healthy and IBD intestinal mucosa developed in our laboratory. The system maintains an apical to basolateral polarity during stimulation due to the presence of a glued cave cylinder. The cylinder is detached at the end of the experiment and the tissue is processed for histology and immunohistochemistry. Cytokines released from the basolateral side are analysed. Results The model system provides several physiological characteristics typical of a mucosal microenvironment including the presence of an organised mucus layer and an apical to basolateral polarity.

A microfluidic chip based model for the study of full thickness human intestinal tissue using dual flow

“…[4][5][6] When either FITC-dextran species was added to the luminal media they passed through the tissue within 25 min (data not shown). Biopsies from five independent patients were studied, and no obvious differences were observed in perfusion kinetics.…”

“…This local reaction leads to an increased influx of intestinal material into the cell wall creating an inflammatory response within the gut. [4][5][6] IBD is a chronic disease without medical cure and requires lifetime care with a possibility of surgery, as well as the increased risk of colorectal cancer. [7][8][9][10] Current research models into IBD either require inducing the disease in murine models or using cell culture, both which fail to fully replicate the extent of the disease seen in humans.…”

Increased Proportions of Bifidobacterium and the Lactobacillus Group and Loss of Butyrate-Producing Bacteria in Inflammatory Bowel Disease

“…Mileti et al (37) found that Lactobacillus paracasei displayed a delay in the development of colitis and a decreased severity of disease but that L. plantarum and L. rhamnosus GG exacerbated the development of dextran sodium sulfate (DSS)-induced colitis. In contrast, Tsilingiri et al (39) found that L. plantarum induced an inflammatory response in the healthy tissue cultured ex vivo at the end of incubation that resembled the response induced by Salmonella. Moreover, L. paracasei, L. plantarum, and L. rhamnosus GG were detrimental in the inflamed tissue derived from IBD patients cultured ex vivo, whereas the supernatant from the culture system of L. paracasei directly acted on the tissue and downregulated the proinflammatory activities of the existing leukocytes (39).…”

A systems biology approach to studying the role of microbes in human health

“…Numerous model systems exist to study the links between gut microbiota and host metabolism, including in vitro cell culture models [4], in vitro gut models [5], ex vivo organ models [6], animal models [7 ,8 ], human in patient studies [9], and cohort studies (e.g. [10,11]).…”