Fig. 5

Gut-homing CD8⁺ T-cell responses. Percentage of activated gut-homing CD8⁺ T cells baseline and on day 6 after starting the 3-day gluten challenge is shown in subjects from each study group: a patients with celiac disease, b patients with suspected gluten-related functional bowel disease symptoms (SGRS), c healthy controls, and d individuals with uncertain diagnosis. In patients with a response at day 6 exceeding the cut-off (dotted red line), the percentage of CD8⁺ CD103⁺ β7^hi CD38⁺ CCR9⁺ cells/total CD8⁺ cells is also shown. Note that including CCR9 eliminates the two false positives (green dots) in the group of uncertain diagnosis. Red dots represent subjects with positive fecal GIP