Bifidobacteria from human origin: interaction with phagocytic cells

ASSAD, S.E.; ROLNY, I.S.; MINNAARD, J.; PÉREZ, P.F.

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2020 vol. 130 p. 1357 - 1367

1364-5072

AbstractAim of the study: Given that phagocytic cells are main players of the hostimmune response, we studied the interaction of bifidobacteria with monocyticTHP-1 cells in nonopsonic conditions.Methods and Results: Association/internalization, cell response (expression ofHLA-DR and TLR2), M1/M2 macrophage polarization and colocalization ofmicro-organisms with Lysotracker or transferrin were evaluated. Screening witheight Bifidobacterium strains showed two patterns of interactions with THP-1cells: high and low association and phagocytosis. Two strains with differentsurface properties were further studied: B. bifidum CIDCA 5310 and B.adolescentis CIDCA 5317. Strain CIDCA 5310 showed higher levels ofcolocalization in lysosome than strain CIDCA 5317. Both strains stimulatedTLR2 expression. Strain CIDCA 5317 significantly increases HLA-DRexpression, however, when cells are stimulated with IFN-c, strain CIDCA 5310induces the highest value of expression. Noteworthy, strain CIDCA 5310 wasable to upregulate both M1 and M2 markers of macrophage polarization.Conclusions: Our results demonstrate that bifidobacteria from human originshow different patterns of interaction with phagocytic cells thus leading todifferent cell responses. These findings add further insight on the mechanismsinvolved in the biologic effects of probiotics.Significance and Impact of the Study: Knowledge of the interaction ofbifidobacteria with key players of the host immune response is paramount forthe understanding of the mechanisms involved in the beneficial effects.