Helicobacter pylori modulates host cell responses by CagT4SS-dependent translocation of an intermediate metabolite of LPS inner core heptose biosynthesis
Fig 3
H. pylori core heptose mutants are able to induce the hummingbird phenotype in human gastric AGS cells (wild type and CRISPR/Cas9 TIFA k/o) independently of IL-8 and TIFA.
A) mock-coincubated AGS wild type (wt) cells; B) AGS wt cells coincubated with strain N6 wt bacteria; C) AGS wt cells coincubated with strain N6 HP0858 (hldE) mutant bacteria; D) AGS wt cells coincubated with N6 HP0858 complemented strain; E) mock-coincubated AGS TIFA CRISPR/Cas9 k/o cells; F) AGS TIFA k/o cells coincubated with N6 wt. Bacteria were coincubated with the cells for 4 h after centrifugation, fixed and microscopic images acquired. Black arrowheads designate some hummingbird phenotype cells for clarity. Size bars (white) represent 50 μm. G), H) Quantitation of hummingbird phenotype in bacteria-coincubated AGS wt cells (G) or AGS TIFA k/o cells (H) as shown in panels A) through F). 1,000 cells for each condition were quantitated for cell length using ImageJ (as detailed in Methods). Mutants (of strain N6) coincubated with the cells shown in panels G) and H) are indicated by the respective gene numbers. Statistically significant differences between mock-coincubated and bacteria-coincubated cells are shown above the graphs (*p<0.05, **p<0.01, **** p< 0.001, calculated by non-parametric Kruskal-Wallis test; ns = non-significant).