Vedolizumab staining of colonic biopsies detected by CLE at inclusion and response to vedolizumab at week 22.

Vedolizumab staining of colonic biopsies detected by CLE at inclusion and response to vedolizumab at week 22.</p

Adalimumab staining of colonic biopsies detected by CLE and response to adalimumab at week 30.

Adalimumab staining of colonic biopsies detected by CLE and response to adalimumab at week 30.</p

S2 Fig -

Absolute counts of T cells (panel A), B cells (panel B) and NK cells (panel D) as determined by flow cytometry in responders (R) and non-responders (NR) to vedolizumab at week 0 (W0) and week 22 (W22). The monocyte blood count (panel C) was measured using the Sysmex XS-800i analyzer. There was no difference of absolute counts of the different cells between responders and non-responders to vedolizumab. In responder patients, the absolute count of monocytes (panel C) decreased significantly between week 0 and 22 and monocytes were also significantly fewer at week 22 in responders compared to non-responders. α4β7 expression was analyzed by flow cytometry using a FITC-conjugated vedolizumab antibody in T cells (panel E), B cells (panel F), NK cells, monocytes (panel G) and NK cells (panel H). There was no difference between responders and non-responders to vedolizumab at week 0 before the initiation of the treatment. At week 22, the number of vedolizumab positive B cells decreased significantly in both responders and non-responders (panel F). (TIF)</p

Patient demographic and disease characteristics at baseline.

Patient demographic and disease characteristics at baseline.</p

Comparison of FITC-labelled vedolizumab and Alexa fluor- labelled adalimumab staining detected by CLE in inflamed and non-inflamed mucosa.

Comparison of FITC-labelled vedolizumab and Alexa fluor- labelled adalimumab staining detected by CLE in inflamed and non-inflamed mucosa.</p

Adalimumab staining of colonic biopsies detected by CLE at inclusion and response to vedolizumab at week 22.

Adalimumab staining of colonic biopsies detected by CLE at inclusion and response to vedolizumab at week 22.</p

DETECT study flow chart.

A total of 23 patients were screened for eligibility and 19 were enrolled in the study and received at least one dose of vedolizumab. Three patients did not meet the inclusion criteria and one patient declined its participation. All patients received vedolizumab at day 0 and week 2, 6 and 14 and were evaluated at week 22. One patient who discontinued vedolizumab between day 0 and week 22 and, who received prematurely adalimumab was considered as a failure of vedolizumab and was analyzed at week 30.</p

Fig 2 -

Representative CLE pictures obtained from the same colonic biopsy after staining with vedolizumab-FITC (panel A, green) and adalimumab-Alexa fluor (panel B, red). Arrows identified positive vedolizumab -FITC positive cells and solid arrows, adalimumab-Alexa fluor positive cells in each panel. CLE images were merged (panel C) and showed an overlay of 80%.</p

S1 Fig -

Representative IFI pictures of slides from formalin-fixed, paraffin-embedded (FFPE) sections of UC colon stained with mAbs against α4β7 (red) and DAPI (blue). Original magnification x 200 (A) & (C). Higher magnification of α4β7+ cells in the colon (B). (TIF)</p

B cell subpopulations analysis for α4β7 expression by flow cytometry using a FITC-conjugated vedolizumab antibody in responders (R) and non-responders (NR) patients at weeks 0 (W0) and 22 (W22).

Plasmablasts and switch B cells decreased between inclusion and week 22 in both groups and the difference was only significant in responder patients. (TIF)</p