title: Bifidobacteria Enhance Antigen Sampling and Processing by Dendritic Cells in Pediatric Inflammatory Bowel Disease.
abstract: Bifidobacteria have been reported to reduce inflammation and contribute to intestinal homeostasis. However, the interaction between these bacteria and the gut immune system remains largely unknown. Because of the central role played by dendritic cells (DCs) in immune responses, we examined in vitro the effects of a Bifidobacteria mixture (probiotic) on DC functionality from children with inflammatory bowel disease. DCs obtained from peripheral blood monocytes of patients with Crohn's disease (CD), ulcerative colitis, and noninflammatory bowel disease controls (HC) were incubated with fluorochrome-conjugated particles of Escherichia coli or DQ-Ovalbumin (DQ-OVA) after a pretreatment with the probiotic, to evaluate DC phenotype, antigen sampling and processing. Moreover, cell supernatants were collected to measure tumor necrosis factor alpha, interferon gamma, interleukin 17, and interleukin 10 production by enzyme-linked immunosorbent assay. DCs from CD children showed a higher bacteria particles uptake and DQ-OVA processing after incubation with the probiotic; in contrast, DC from both ulcerative colitis and HC showed no significant changes. Moreover, a marked tumor necrosis factor alpha release was observed in DC from CD after exposure to E. coli particles, whereas the probiotic did not affect the production of this proinflammatory cytokine. In conclusion, the Bifidobacteria significantly improved the antigen uptake and processing by DCs from patients with CD, which are known to present an impaired autophagic functionality, whereas, in DCs from ulcerative colitis and HC, no prominent effect of probiotic mixture was observed. This improvement of antigen sampling and processing could partially solve the impairment of intestinal innate immunity and reduce uncontrolled microorganism growth in the intestine of children with inflammatory bowel disease.
authors.affiliation: *Department of Translational Medical Science, Section of Pediatrics, University of Naples "Federico II," Naples, Italy; †Department of Biomedicine, Institute of Protein Biochemistry, CNR, Naples, Italy; and ‡Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II," Naples, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Strisciuglio
authors.forename: Erasmo
authors.initials: E
authors.lastname: Miele
authors.forename: Francesca P
authors.initials: FP
authors.lastname: Giugliano
authors.forename: Serena
authors.initials: S
authors.lastname: Vitale
authors.forename: Marialuisa
authors.initials: M
authors.lastname: Andreozzi
authors.forename: Alessandra
authors.initials: A
authors.lastname: Vitale
authors.forename: Maria R
authors.initials: MR
authors.lastname: Catania
authors.forename: Annamaria
authors.initials: A
authors.lastname: Staiano
authors.forename: Riccardo
authors.initials: R
authors.lastname: Troncone
authors.forename: Carmen
authors.initials: C
authors.lastname: Gianfrani
mesh_terms: D000293:Adolescent; D001644:Bifidobacterium; D002648:Child; D002675:Child, Preschool; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007223:Infant; D015212:Inflammatory Bowel Diseases / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D008297:Male; D018613:Microscopy, Confocal; D019936:Probiotics / Q000494:pharmacology*
chemical_list: D016207:Cytokines