The Smallest Intestine (TSI) – a low volumein vitromodel of the small intestine with increased throughput

Aims To develop a low volume in vitro model with increased throughput simulating the human small intestine, incorporating the presence of ileal microbiota, to study microbial behaviour in the small intestine. Methods and Results The Smallest Intestine in vitro model (TSI) was developed. During the simulated passage of the small intestine bile is absorbed by dialysis and pH adjusted to physiologically relevant level. A consortium of seven representative bacterial members of the ileum microbiota is included in the ileal stage of the model. It was found that the model can be applied for the testing of survival of probiotic bacteria in upper intestine. Moreover, it was found, that the presence of the ileal microbiota significantly impacted probiotic survival. Conclusions TSI allows testing a substantial number of samples, at low cost and short time, and is thus suitable as an in vitro screening platform. Multiples of five reactors can be added to increase the number of biological and technical replicates. Significance and Impact of the Study TSI serves as an alternative for costly and low throughput in vitro models currently existing on the market. Above that, significance of small intestine bacteria presence on survival of probiotic bacteria in the upper intestine was proved.