P0752 - Preterm infants fed B. infantis EVC001 Demonstrate Significant Reduction in Intestinal Inflammation via Modulation of Gut Microbiome Composition

Gut microbiome dysbiosis negatively affects the health of premature infants and increases risk for infection and diminished growth. Preterm infants are colonized with nosocomially acquired gut microbes, including pathogens, and experience enteric inflammation, which has been related to adverse clinical outcomes. There have been limited probiotic interventions that show meaningful improvement of quantifiable health indicators. Therefore, we hypothesized colonizing the preterm infant gut microbiome with an infant-adapted organism, Bifidobacterium longum subsp. infantis (B. infantis) EVC001, that can utilize the full concentration of HMOs in human milk would increase overall microbiome function and could provide a meaningful application to reduce carriage of antibiotic resistant microbes and decrease enteric inflammation as a proactive measure to address morbidities associated with premature birth.

Here we prospectively and longitudinally followed a cohort of preterm infants in two Kaiser Permanente Southern California neonatal intensive care units (Anaheim and Irvine, CA). All infants in the hospital born at less than 32 weeks gestational age OR less than 1500 g received 8 x 109 CFU activated B. infantis EVC001 suspended in MCT oil daily as standard of care. Fecal samples (n = 298) were collected during routine diaper changes and were subjected to shotgun metagenomics and cytokine profiling.

Our results demonstrated that feeding B. infantis EVC001to preterm infants resulted in significant beneficial impacts on enteric inflammatory profile, human milk utilization, and that human milk feeding facilitates colonization by B. infantis EVC001. Specifically, preterm infants fed EVC001 had significantly lower levels of calprotectin, IL-4, IL-8, IL-17A, and TNF- compared to similar aged infants that were not fed a probiotic (P = 0.034, 0.039, 0.039, 0.034, and 0.0008, respectively). Further, preterm infants fed B. infantis EVC001 required fewer antibiotic exposures and had a significant reduction in antibiotic resistance gene load (P < 0.05). Importantly, we also observed a significant reduction of diaper rash in the infants that were fed B. infantis EVC001 compared to infants that were not fed probiotics (P = 0.024).

Our findings indicate gut dysbiosis (i.e. the absence of Bifidobacterium) is associated with increased intestinal inflammation and antibiotic resistance gene carriage in preterm infants. Early feeding of B. infantis EVC001 along with human milk represents a novel strategy for controlling the composition of the premature infant gut microbiome, as well as preventing dysbiosis-driven enteric inflammation, dissemination of antibiotic resistant bacteria, and incidence of diaper rash. These data show feeding B. infantis EVC001 to premature infants provides a meaningful strategy to reduce gut dysbiosis and antibiotic resistant gene abundance, as well as decrease enteric inflammation and may reduce the risk of morbidity and mortality in hospitalized infants.