RESUMEN
Engineered bacteria (synthetic biotics) represent a new class of therapeutics that leverage the tools of synthetic biology. Translational testing strategies are required to predict synthetic biotic function in the human body. Gut-on-a-chip microfluidics technology presents an opportunity to characterize strain function within a simulated human gastrointestinal tract. Here, we apply a human gut-chip model and a synthetic biotic designed for the treatment of phenylketonuria to demonstrate dose-dependent production of a strain-specific biomarker, to describe human tissue responses to the engineered strain, and to show reduced blood phenylalanine accumulation after administration of the engineered strain. Lastly, we show how in vitro gut-chip models can be used to construct mechanistic models of strain activity and recapitulate the behavior of the engineered strain in a non-human primate model. These data demonstrate that gut-chip models, together with mechanistic models, provide a framework to predict the function of candidate strains in vivo.
Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Terapia Biológica/métodos , Microbioma Gastrointestinal , Dispositivos Laboratorio en un Chip , Modelos Biológicos , Fenilcetonurias/terapia , Animales , Células CACO-2 , Simulación por Computador , Escherichia coli/metabolismo , Ingeniería Genética , Células HT29 , Humanos , Técnicas In Vitro , Microfluídica , Fenilalanina/metabolismo , Fenilcetonurias/metabolismo , Fenilcetonurias/microbiología , Primates , Biología SintéticaAsunto(s)
Bacterias/genética , Bacterias/metabolismo , Terapia Biológica/métodos , Animales , Bacteroides/genética , Bacteroides/metabolismo , Terapia Biológica/efectos adversos , Ensayos Clínicos como Asunto , Colitis/microbiología , Colitis/terapia , Escherichia coli/genética , Escherichia coli/metabolismo , Transferencia de Gen Horizontal/ética , Infecciones por VIH/microbiología , Infecciones por VIH/prevención & control , Humanos , Lactobacillus/genética , Lactobacillus/metabolismo , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Ratones , Fenilalanina/metabolismo , Fenilcetonurias/microbiología , Fenilcetonurias/terapiaRESUMEN
BACKGROUND AND AIMS: Phenylalanine (Phe) restricted diet, combined with Phe-free l-amino acid supplementation, is the mainstay of treatment for phenylketonuria (PKU). Being the diet a key factor modulating gut microbiota composition, the aim of the present paper was to compare dietary intakes, gut microbiota biodiversity and short chain fatty acids (SCFAs) production in children with PKU, on low-Phe diet, and in children with mild hyperphenylalaninemia (MHP), on unrestricted diet. METHODS AND RESULTS: We enrolled 21 PKU and 21 MHP children matched for gender, age and body mass index z-score. Dietary intakes, including glycemic index (GI) and glycemic load (GL), and fecal microbiota analyses, by means of denaturing gradient gel electrophoresis (DGGE) and Real-time PCR were assessed. Fecal SCFAs were quantified by gas chromatographic analysis. RESULTS: We observed an increased carbohydrate (% of total energy), fiber and vegetables intakes (g/day) in PKU compared with MHP children (p = 0.047), as well a higher daily GI and GL (maximum p < 0.001). Compared with MHP, PKU showed a lower degree of microbial diversity and a decrease in fecal butyrate content (p = 0.02). Accordingly, two of the most abundant butyrate-producing genera, Faecalibacterium spp. and Roseburia spp., were found significantly depleted in PKU children (p = 0.02 and p = 0.03, respectively). CONCLUSION: The low-Phe diet, characterized by a higher carbohydrate intake, increases GI and GL, resulting in a different quality of substrates for microbial fermentation. Further analyses, thoroughly evaluating microbial species altered by PKU diet are needed to better investigate gut microbiota in PKU children and to eventually pave the way for pre/probiotic supplementations.