Intestinal microbiota regulates tryptophan metabolism following oral infection with Toxoplasma gondii

SANTOS, LILIANE M.; COMMODARO, ALESSANDRA G.; VASQUEZ, ALICIA R. R.; KOHLHOFF, MARKUS; DE PAULA GUERRA, DANIEL A.; COIMBRA, RONEY S.; MARTINS FILHO, OLINDO A.; TEIXEIRA CARVALHO, ANDREA; RIZZO, LUIZ V.; VIEIRA, LEDA Q.; SERRA, HORACIO M.

PARASITE IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020

0141-9838

troduction: The intestinal microbiota plays an important role in modulating host immune responses. Oral Toxop/asma gondii infection can promote intestinal inflam­mation in certain mice strains. The 1DO-AhR axis may control tryptophan (Trp) me­tabolism constituting an important immune regulatory mechanism in inflammatory settings. Aims: In the present study, we investigated the role of the intestinal microbiota on Trp metabolism during oral infection with T gondii. Methods and results: Mice were treated with antibiotics for four weeks and then infected with T gondii by gavage. Histopathology and immune responses were eval­uated 8 days after infection. We found that depletion of intestinal microbiota by antibiotics contributed to resistance against T gondii infection and led to reduced expression of AhR on dendritic and Treg cells. Mice depleted of Gram-negative bac­teria presented higher levels of systemic Trp, downregulation of AhR expression and increased resistance to in