Profiling of the human intestinal microbiome and bile acids under physiologic conditions using an ingestible sampling device

Shalon, D.; Culver, R. N.; Grembi, J. A.; Folz, J.; Treit, P.; Dethlefsen, L.; Meng, X.; Yaffe, E.; Spencer, S.; Shi, H.; Aranda-Diaz, A.; Patterson, A. D.; Triadafilopoulos, G.; Holmes, S. P.; Mann, M.; Fiehn, O.; Relman, D.; Huang, K.

doi:10.1101/2022.01.19.476920

bioRxiv · 10.1101/2022.01.19.476920

Profiling of the human intestinal microbiome and bile acids under physiologic conditions using an ingestible sampling device

Shalon, D.·Culver, R. N.·Grembi, J. A.·Folz, J.·Treit, P.·Dethlefsen, L.·Meng, X.·Yaffe, E.·Spencer, S.·Shi, H.·Aranda-Diaz, A.·Patterson, A. D.·Triadafilopoulos, G.·Holmes, S. P.·Mann, M.·Fiehn, O.·Relman, D.·Huang, K.

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Abstract

The spatiotemporal structure of the human microbiome and metabolome reflects and determines regional intestinal physiology and may have implications for disease. Yet, we know little about the distribution of microbes and their products in the gut because of reliance on stool samples and limited access only to some regions of the gut using endoscopy in fasting or sedated individuals. To address these deficiencies, we developed and evaluated a safe, ingestible device that collects samples from multiple regions of the human intestinal tract during normal digestion. The collection of 240 intestinal samples from 15 healthy individuals using the device revealed significant differences between microbes and metabolites present in the intestines versus stool. Certain microbial taxa were differentially enriched, and bile acid profiles varied along the intestines and were highly distinct from those of stool. Correlations between gradients in bile acid concentrations and microbial abundance predicted species that altered the bile acid pool through deconjugation. Overall, we identified heterogeneous intestinal profiles of bacterial taxa and metabolites indicating that non-invasive multi-regional sampling of the intestinal tract under physiological conditions can help elucidate the roles of the gut microbiome and metabolome in human physiology and disease.

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Shalon, D., Culver, R. N., Grembi, J. A., Folz, J., Treit, P., Dethlefsen, L., Meng, X., Yaffe, E., Spencer, S., Shi, H., Aranda-Diaz, A., Patterson, A. D., Triadafilopoulos, G., Holmes, S. P., Mann, M., Fiehn, O., Relman, D., Huang, K.. 2022-01-20. Profiling of the human intestinal microbiome and bile acids under physiologic conditions using an ingestible sampling device. https://doi.org/10.1101/2022.01.19.476920

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