Marianna Parlato, Fabienne Charbit-Henrion, Jie Pan, Claudio Romano, Rémi Duclaux-Loras, Marie-Helene Le Du, Neil Warner, Paola Francalanci, Julie Bruneau, Marc Bras, Mohammed Zarhrate, Bernadette Bègue, Nicolas Guegan, Sabine Rakotobe, Nathalie Kapel, Paola De Angelis, Anne M Griffiths, Karoline Fiedler, Eileen Crowley, Frank Ruemmele, Aleixo M Muise, Nadine Cerf-Bensussan
Herein, we report the first identification of biallelic-inherited mutations in ALPI as a Mendelian cause of inflammatory bowel disease in two unrelated patients. ALPI encodes for intestinal phosphatase alkaline, a brush border metalloenzyme that hydrolyses phosphate from the lipid A moiety of lipopolysaccharides and thereby drastically reduces Toll-like receptor 4 agonist activity. Prediction tools and structural modelling indicate that all mutations affect critical residues or inter-subunit interactions, and heterologous expression in HEK293T cells demonstrated that all ALPI mutations were loss of function...
March 22, 2018: EMBO Molecular Medicine