학술논문

TTC7A mutations disrupt intestinal epithelial apicobasal polarity
Document Type
Report
Source
Journal of Clinical Investigation. January 1, 2014, Vol. 124 Issue 1, p328, 10 p.
Subject
France
Language
English
ISSN
0021-9738
Abstract
Multiple intestinal atresia (MIA) is a rare cause of bowel obstruction that is sometimes associated with a combined immunodeficiency (CID), leading to increased susceptibility to infections. The factors underlying this rare disease are poorly understood. We characterized the immunological and intestinal features of 6 unrelated MIA-CID patients. All patients displayed a profound, generalized lymphocytopenia, with few lymphocytes present in the lymph nodes. The thymus was hypoplastic and exhibited an abnormal distribution of epithelial cells. Patients also had profound disruption of the epithelial barrier along the entire gastrointestinal tract. Using linkage analysis and whole-exome sequencing, we identified 10 mutations in tetratricopeptide repeat domain-7A (TTC7A), all of which potentially abrogate TTC7A expression. Intestinal organoid cultures from patient biopsies displayed an inversion of apicobasal polarity of the epithelial cells that was normalized by pharmacological inhibition of Rho kinase. Our data indicate that TTC7A deficiency results in increased Rho kinase activity, which disrupts polarity, growth, and differentiation of intestinal epithelial cells, and which impairs immune cell homeostasis, thereby promoting MIA-CID development.
Introduction Multiple intestinal atresia (MIA) is characterized by widespread atresia, extending from the stomach to the rectum, and homogenous calcifications in the abdominal cavity (1). Patients with MIA can develop [...]