Analysis of SHIP1 expression and activity in Crohn’s disease patients

BACKGROUND SH2 domain containing inositol-5-phosphatase (SHIP1) is an important modulator of innate and adaptive immunity. In mice, loss of SHIP1 provokes severe ileitis resembling Crohn's disease (CD), as a result of deregulated immune responses, altered cytokine production and intestinal fibrosis. Recently, SHIP1 activity was shown to be correlated to the presence of a CD-associated single nucleotide polymorphism in ATG16L1. Here, we studied SHIP1 activity and expression in an adult cohort of CD patients. METHODS SHIP1 activity, protein and mRNA expression in peripheral blood mononuclear cells from CD patients in clinical remission were determined by Malachite green assay, Western blotting and qRT-PCR respectively. Genomic DNA was genotyped for ATG16L1 rs2241880. RESULTS SHIP1 protein levels are profoundly diminished in a subset of patients; however, SHIP1 activity and expression are not correlated to ATG16L1 SNP status in this adult cohort. CONCLUSIONS Aberrant SHIP1 activity can contribute to disease in a subset of adult CD patients, and warrants further investigation.