P0117Fibroblast activation protein is selectively expressed by CD90+ fibroblasts in inflammatory bowel disease-associated intestinal fibrosis

Abstract Background Intestinal fibrosis is a common complication in inflammatory bowel disease (IBD), and diagnostic modalities to detect and determine the degree of fibrosis are limited. Fibroblast activation protein (FAP) is virtually absent in healthy tissues, but is increased in malignancies, and in immune-mediated inflammatory diseases. Here, we investigated the presence of FAP in fibrostenotic and inflamed resection specimens from Crohn’s disease (CD) and ulcerative colitis (UC) patients and defined its cellular and spatial distribution. Methods FAP mRNA (not shown) and protein levels were determined in tissue samples from CD, UC and (non-IBD) controls using quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC). Immunohistochemical stainings (H134. Conflict of interest: Ms. Lartey, Dalia: no COI Van Os, Bram: No conflict of interest Ke, Bo-Jun: No conflict of interest Van Wijnbergen, Kelly: No conflict of interest De Hertogh, Gert: Other: Fees to my institution KULeuven for my activities as central pathology reviewer for: Centocor and Eli Lilly Barnhoorn, Marieke: No conflicts of interest. Matteoli, Gianluca: Grant: We are recipient of the opnMe research grant from Boehringer Ingelheim. Buskens, Christianne J.: Grant: C. Buskens has received an unrestricted grant from Boehringer Ingelheim and Roche Personal Fees: C. Buskens has received consultancy fees and/or speaker’s honoraria from Tillotts, Takeda, MSD and Janssen jarmilla, van der bilt: No conflict of interest D’Haens, Geert: Grant: Pfizer, BMS, Johnson and Johnson, Abbvie, Alimentiv BV, Eli Lilly, Takeda, Prometheus Laboratories Personal Fees: Abbvie, Abivax, Agomab, Alimentiv, Anaptys Bio, AstraZeneca, Bristol Meiers Squibb, Boehringer Ingelheim, Celltrion, Eli Lilly, Exeliom Biosciences, Galapagos, Glaxo Smith Kline, Dr Falk Pharma, Pfizer, Johnson and Johnson, Merck, Mirador, Polpharma, Procise Diagnostics, Prometheus Biosciences, Sorriso Pharma, Spyre, Takeda, Ventyx Grootjans, Joep: No conflict of interest Wildenberg, Manon: Received research grant support from Hoffman-La Roche, Boehringer-Ingelheim Löwenberg, Mark: No relevant CoI to disclose