Effect of human child or adult digestion reproduced in a dynamic in vitro gastrointestinal model on Cryptosporidium parvum transcriptome

The impact of digestive physicochemical parameters on Cryptosporidium parvum transcriptome was analysed in a human and age-dependent context using a dynamic in vitro gastrointestinal model. The sophisticated TIM-1 in vitro model was used for a comparative analysis of C. parvum gene expression under the digestive conditions encountered in young children (from 6 months to 2 years) or in adults following the simulated ingestion of a glass of water contaminated with C. parvum oocysts. The C. parvum gene expression profile was analysed by RNA-sequencing in the inoculum, as well as the gastric and ileal effluents collected from the TIM-1 system. Results showed that time and compartment of digestion lead to the strongest modification of parasite transcriptome. Accordingly, the highest number of differentially expressed genes was observed in parasite samples collected in child or adult ileal effluents between 120 and 180 min of digestion, where invasive stages (sporozoites) are predominant. Five samples, three replicates per sample. Oocyst inoculum sample (1); Gastric effluents collected from the TIM-1 between 0 and 20 min of child (2) or adult (3) digestion; Ileal effluents collected from the TIM-1 between 120 and 180 min of child (4) or adult (5) digestion.