18 research outputs found
Is it Time for Reviewer 3 to Request Human Organ Chip Experiments Instead of Animal Validation Studies?
Duodenum intestine-chip for preclinical drug assessment in a human relevant model
Induction of intestinal drug metabolizing enzymes can complicate the development of new drugs, owing to the potential to cause drug-drug interactions (DDIs) leading to changes in pharmacokinetics, safety and efficacy. The development of a human-relevant model of the adult intestine that accurately predicts CYP450 induction could help address this challenge as species differences preclude extrapolation from animals. Here, we combined organoids and Organs-on-Chips technology to create a human Duodenum Intestine-Chip that emulates intestinal tissue architecture and functions, that are relevant for the study of drug transport, metabolism, and DDI. Duodenum Intestine-Chip demonstrates the polarized cell architecture, intestinal barrier function, presence of specialized cell subpopulations, and in vivo relevant expression, localization, and function of major intestinal drug transporters. Notably, in comparison to Caco-2, it displays improved CYP3A4 expression and induction capability. This model could enable improved in vitro to in vivo extrapolation for better predictions of human pharmacokinetics and risk of DDIs. © Kasendra et al
Species-specific enhancement of enterohemorrhagic E. coli pathogenesis mediated by microbiome metabolites
Abstract Background Species-specific differences in tolerance to infection are exemplified by the high susceptibility of humans to enterohemorrhagic Escherichia coli (EHEC) infection, whereas mice are relatively resistant to this pathogen. This intrinsic species-specific difference in EHEC infection limits the translation of murine research to human. Furthermore, studying the mechanisms underlying this differential susceptibility is a difficult problem due to complex in vivo interactions between the host, pathogen, and disparate commensal microbial communities. Results We utilize organ-on-a-chip (Organ Chip) microfluidic culture technology to model damage of the human colonic epithelium induced by EHEC infection, and show that epithelial injury is greater when exposed to metabolites derived from the human gut microbiome compared to mouse. Using a multi-omics approach, we discovered four human microbiome metabolites—4-methyl benzoic acid, 3,4-dimethylbenzoic acid, hexanoic acid, and heptanoic acid—that are sufficient to mediate this effect. The active human microbiome metabolites preferentially induce expression of flagellin, a bacterial protein associated with motility of EHEC and increased epithelial injury. Thus, the decreased tolerance to infection observed in humans versus other species may be due in part to the presence of compounds produced by the human intestinal microbiome that actively promote bacterial pathogenicity. Conclusion Organ-on-chip technology allowed the identification of specific human microbiome metabolites modulating EHEC pathogenesis. These identified metabolites are sufficient to increase susceptibility to EHEC in our human Colon Chip model and they contribute to species-specific tolerance. This work suggests that higher concentrations of these metabolites could be the reason for higher susceptibility to EHEC infection in certain human populations, such as children. Furthermore, this research lays the foundation for therapeutic-modulation of microbe products in order to prevent and treat human bacterial infection
Clostridium difficile flagella induce a pro-inflammatory response in intestinal epithelium of mice in cooperation with toxins
3D Bioelectronic Model of the Human Intestine
Organ on chip (OoC) technologies have the potential to improve the translation
of promising therapies currently failing in clinical trials at great expense and
time due to dissimilarities between animal and human biology. Successful OoC
models integrate human cells within 3D tissues with surrounding biomolecular
components, and have benefited from the use of inert 3D gels and scaffolds
used as templates, prompting tissue formation. However, monitoring technologies used to assess tissue integrity and drug effects are ill adapted to 3D
biology. Here, a tubular electroactive scaffold serves as a template for a 3D
human intestine, and enables dynamic electrical monitoring of tissue formation
over 1 month. Cell- and extracellular matrix component-invoked changes in the
properties of the scaffold alleviate the need for posthoc placement of invasive
metallic electrodes or downstream analyses. Formation of in vivo-like stratified
and polarized intestinal tissue compete with lumen contrasts with other quasi3D models of the intestine using rigid porous membrane to separate cell types.
These results provide unprecedented real-time information on tissue formation with highly sensitive multimodal operation, thanks to dual electrode and
transistor operation. This device and the methodology for tissue growth within
it represents a paradigm shift for disease modeling and drug discover