Fecal Microbiota Transplantation and Other Gut Microbiota Manipulation Strategies

Abstract

The gut microbiota is composed of bacteria, archaea, phages, and protozoa. It is now well known that their mutual interactions and metabolism influence host organism pathophysiology. Over the years, there has been growing interest in the composition of the gut microbiota and intervention strategies in order to modulate it. Characterizing the gut microbial populations represents the first step to clarifying the impact on the health/illness equilibrium, and then developing potential tools suited for each clinical disorder. In this review, we discuss the current gut microbiota manipulation strategies available and their clinical applications in personalized medicine. Among them, FMT represents the most widely explored therapeutic tools as recent guidelines and standardization protocols, not only for intestinal disorders. On the other hand, the use of prebiotics and probiotics has evidence of encouraging findings on their safety, patient compliance, and inter-individual effectiveness. In recent years, avant-garde approaches have emerged, including engineered bacterial strains, phage therapy, and genome editing (CRISPR-Cas9), which require further investigation through clinical trials.

Keywords: FMT; diet; engineered bacteria; eubiosis; gut microbiota modulation; personalized medicine; phages; prebiotics; probiotics.

Figure 1

Microbiota diversity and richness are strongly influenced by the host and environmental factors.

Figure 2

Impact of diet on intestinal microbiota and health outcomes. SCFA = short chain fatty acids; PYY = peptide YY; GLP-1 = glucagon-like peptide 1; LPS = lipopolysaccharide; TMAO = trimethylamine N-oxide.

Figure 3

Engineering steps for a candidate chassis wild-type bacterium.

Figure 4

Strengths and weaknesses of phage therapy.