title: Multiple intestinal atresia with combined immune deficiency related to TTC7A defect is a multiorgan pathology: study of a French-Canadian-based cohort.
abstract: Hereditary multiple intestinal atresia (HMIA) is a rare cause of intestinal obstruction in humans associated with a profound combined immune deficiency. Deleterious mutations of the tetratricopeptide repeat domain-7A (TTC7A) gene lead to HMIA, although the mechanism(s) causing the disease in TTC7A deficiency has (have) not yet been clearly identified. To evaluate the consequences of TTC7A deficiency, we studied the morphology of several organs from HMIA patients at different developmental stages, as well as the expression of the TTC7A protein. We performed histological and immunohistochemical analyses on biopsies and autopsies of 6 patients and 1 fetus with HMIA. Moreover, we characterized for the first time the expression of the TTC7A protein by immunostaining it in several organs from control (including fetal samples), infants, and 1 fetus with HMIA. Besides the gastrointestinal tract, HMIA disease was associated with morphological alterations in multiple organs: thymus, lung, spleen, and liver. Moreover, we demonstrated that normal TTC7A protein was expressed in the cytoplasm of epithelial cells of the intestine, thymus, and pancreas. Surprisingly, altered TTC7A protein was highly expressed in tissues from patients, mainly in the epithelial cells. We have established that HMIA associated with a TTC7A defect is characterized by multiorgan impairments. Overall, this report suggests that TTC7A protein is critical for the proper development, preservation, and/or function of thymic and gastrointestinal epithelium.
authors.affiliation: From the Department of Microbiology, Infectiology and Immunology, University of Montreal, Montreal, Canada (IF, EH, FLD); Department of Microbiology and Immunology, CHU Sainte-Justine, Montreal, Canada (IF, FLD); CHU Sainte-Justine Research Center, Montreal, Canada (IF, NP, EH, HD, FLD); Department of Pathology and Cell Biology, CHU Sainte-Justine and University of Montreal, Montreal, Canada (NP); Department of Paediatrics, University of Montreal, Montreal, Canada (VM, EH, HD, FLD); Division of Gastroenterology, Hepatology and Nutrition, CHU Sainte-Justine, Montreal, Canada (VM); Histology Facility, IRIC, University of Montreal, Montreal, Montreal, Canada (MB); Medical Genetics Service, University of Sherbrooke, Sherbrooke, Canada (BM); and Division of Rheumatology, Immunology and Allergology, CHU Sainte-Justine Montreal, Canada (EH, HD, FLD).
authors.forename: Isabel
authors.initials: I
authors.lastname: Fernandez
authors.forename: Natalie
authors.initials: N
authors.lastname: Patey
authors.forename: Valérie
authors.initials: V
authors.lastname: Marchand
authors.forename: Mirela
authors.initials: M
authors.lastname: Birlea
authors.forename: Bruno
authors.initials: B
authors.lastname: Maranda
authors.forename: Elie
authors.initials: E
authors.lastname: Haddad
authors.forename: Hélène
authors.initials: H
authors.lastname: Decaluwe
authors.forename: Françoise
authors.initials: F
authors.lastname: Le Deist
mesh_terms: D017209:Apoptosis; D001284:Atrophy; D002114:Calcinosis; D002170:Canada; D016022:Case-Control Studies; D015331:Cohort Studies; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D005333:Fetus; D006801:Humans; D007150:Immunohistochemistry; D007153:Immunologic Deficiency Syndromes / Q000235:genetics*; D007223:Infant; D007231:Infant, Newborn; D007409:Intestinal Atresia / Q000235:genetics*; D007413:Intestinal Mucosa / Q000473:pathology; D007415:Intestinal Obstruction / Q000209:etiology; D007422:Intestines / Q000002:abnormalities; D008099:Liver / Q000473:pathology; D008168:Lung / Q000473:pathology; D008264:Macrophages / Q000378:metabolism; D008297:Male; D009102:Multiple Organ Failure / Q000209:etiology; D009154:Mutation; D011506:Proteins / Q000235:genetics* / Q000378:metabolism; D013154:Spleen / Q000473:pathology; D013950:Thymus Gland / Q000473:pathology
chemical_list: D011506:Proteins; C583818:TTC7A protein, human