Calprotectin-sensing EcN can differentiate stool samples from patients with active IBD and those in remission. (A) Stool samples were collected from patients with active IBD (n = 6), IBD in remission (n = 5), and no IBD (n = 6). CS EcN-GFP was cocultured with stool samples and GFP was quantified using the TECAN infinite plate reader after 12 h. (B) GFP/OD600 of CS EcN-GFP cocultured with fecal samples of patients with active IBD (n = 6), IBD in remission (n = 5), and no IBD (n = 6). GFP/OD600 was quantified by the TECAN infinite plate reader immediately after coculturing and 12 h after coculturing. (C) Laboratory-measured calprotectin values obtained from electronic medical records retrospectively of patients with active IBD (n = 6), IBD in remission (n = 5), and no IBD (n = 6) plotted with their respective GFP/OD600 intensities. (D) Representative flow cytometry images quantifying GFP positive cell populations in CS EcN-GFP that were cocultured with fecal samples of patients with no IBD, IBD in remission, and active IBD after 3 h. (E) %GFP-positive cells from flow cytometry time course of CS EcN-GFP after coculturing with patient samples. *P < 0.05 for Student’s unpaired t test for indicated comparisons. Data are represented as mean ± SEM.