INTRODUÇÃO: Culture-independent microbiota analysis has allowed characterizing the microbiota of bacterial diversity in CF and is increasingly being used to examine fungal communities.
OBJETIVO: To analyze the effects of CF and its management on the gut microbiota and mycobiota comparing these communities in stool samples from a CF cohort and healthy infants.
METODOLOGIA: This is a prospective observational cohort study, with cross-sectional and longitudinal components for sample acquisition and data analysis.Ten 3-month-old CF infants diagnosed by neonatal screening, sweat chloride test, and confirmatory genetic testing (6 homozygotes and 4 heterozygotes for the delF508 mutation), and five healthy infants, were included in the study. Each study participant collected a stool sample every three months, during 12 months, totaling four samples (3, 6, 9 and 12 months, respectively). Microbial composition was determined using 16S rRNA and ITS1 based sequencing.The libraries were sequenced using the MiSeq Sequencing System equipment (Illumina Inc., USA). The sequences were analyzed using a proprietary pipeline (Sentinel, Neoprospecta Microbiome Technologies, Brazil).
RESULTADOS: Overall, 60 stool samples of CF and healthy infants were collected regularly during the first 12 months of life. Infant fecal mycobiota was characterized by a low relative abundance of fungi composition and richness. Only two phyla (Ascomycota and Basidiomycota) were identified in the gut mycobiota of CF and healthy infants. Ascomycota was the most abundant fungi phylum. A total of 15 fungi genera and 19 differentially abundant species were identified between CF and healthy infants. At phylum level of gut microbiota, there was a significant decrease in Bacteroidetes and Actinobacteria, with an increase in Proteobacteria in all collection periods. Fusobacteria was increased in CF infants from the 6-month collection and there was an increase in Firmicutes in the periods of 3 and 9 months. At the genus level, 46 genera were differentially abundant between CF and health controls samples. This included the decrease in Bifdobacterium spp., Rothia spp., Bacteroides spp., Prevotella spp. and Parabacterioides spp. and increase in Clostridium spp., Veillonella spp., Blautia spp., E. coli spp., Citrobacter spp., and Haemophilus spp. Alpha and beta diversity analysis was performed to determine the gut microbiota diversity of CF samples compared to healthy controls. The alpha diversity was significantly different over samples of three months of life but no clear difference of the beta diversity was observed.
CONCLUSÃO: We observed significant differences in overall microbiota composition diversity and dynamics development between infants with CF and healthy infants beginning in the first months of life. The role of inter-kingdom crosstalks in the intestinal microbiome needs further studies and new therapeutic targets for maintaining homeostasis and halt CF progression.
