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Tibboel, D.

Publications and source records attributed to Tibboel, D..

4 recordsLinked to original sources

Distinct roles for SOX2 and SOX21 in differentiation, distribution and maturation of pulmonary neuroendocrine cells

Pulmonary neuroendocrine (NE) cells represent a small population in the airway epithelium, but despite this, hyperplasia of NE cells is associated with several lung diseases, such as congenital diaphragmatic hernia and bronchopulmonary dysplasia. The molecular mechanisms causing the development of NE cell hyperplasia remains poorly understood. Previously, we showed that the SOX21 modulates the SOX2-initiated differentiation of epithelial cells in the airways (Eenjes, 2021). Here, we show that precursor NE cells start to develop in the SOX2+SOX21+ airway region and that SOX21 suppresses the differentiation of airway progenitors to precursor NE cells. During development, clusters of NE cells start to form and NE cells mature by expressing neuropeptide proteins, such as CGRP. Deficiency in SOX2 resulted in decreased clustering, while deficiency in SOX21 increased both the numbers of NE ASCL1+ precursor cells early in development, and the number of cell clusters at E18.5. In addition, at the end of gestation (E18.5), a number of NE cells in Sox2 heterozygous mice, did not yet express CGRP suggesting a delay in maturation. In conclusion, SOX2 and SOX21 function in the initiation, migration and maturation of NE cells.

developmental biology↗

SOX21 modulates SOX2-initiated differentiation of epithelial cells in the extrapulmonary airways

SOX2 expression levels are crucial for the balance between maintenance and differentiation of airway progenitor cells during development and regeneration. Here, we describe SOX21 patterning of the proximal airway epithelium which coincides with high levels of SOX2. Airway progenitor cells in this SOX2+/SOX21+ zone show differentiation to basal cells, specifying cells for the extrapulmonary airways. We show that loss of SOX21 results in increased differentiation of progenitor cells during murine lung development. SOX21 inhibits SOX2-induced differentiation by antagonizing SOX2 binding on different promotors. SOX21 remains expressed in adult tracheal epithelium and submucosal glands, where SOX21 modulates SOX2-induced differentiation in a similar fashion. Using fetal lung organoids and adult bronchial epithelial cells, we show that SOX2+SOX21+ regionalization is conserved in human. Thus SOX21 modulates SOX2-initiated differentiation in extrapulmonary epithelial cells during development and regeneration after injury.

cell biology↗

Abnormal vertebral patterns in genetically heterogeneous deceased fetuses and neonates: evidence of selection against variations

ObjectiveTo assess the vertebral pattern in a cohort of deceased fetuses and neonates, and to study the possible impact of DNA Copy Number Variations (CNVs) in coding regions and/or disturbing enhancers on the development of the vertebral pattern.\n\nMethodRadiographs of 445 fetuses and infants, deceased between 2009 and 2015, were assessed. Terminations of pregnancies, stillbirths and neonatal deaths were included. Patients were excluded if the vertebral pattern could not be determined. Copy number profiles of 265 patients were determined using single nucleotide polymorphism array.\n\nResults274/374 patients (73.3%) had an abnormal vertebral pattern. Cervical ribs were present in 188/374 (50.3%) and were significantly more common in stillbirths (69/128 (53.9%)) and terminations of pregnancies (101/188 (53.7%)), compared to live births (18/58, 31.0%, p = 0.006). None of the rare CNVs were recurrent or overlapped candidate genes for vertebral patterning.\n\nConclusionThe presence of an abnormal vertebral pattern, particularly in the cervical region, could be a sign of disruption at critical, highly interactive and conserved stages of embryogenesis. The vertebral pattern might provide valuable information regarding fetal and neonatal outcome. CNV analyses did not identify a mutual genetic cause for the occurrence of vertebral patterning abnormalities, indicating genetic heterogeneity.

evolutionary biology↗

Models for infantile hypertrophic pyloric stenosis development in patients with esophageal atresia

Patients born with esophageal atresia (EA) have a 30 times higher prevalence of infantile hypertrophic pyloric stenosis (IHPS). This makes sense from a developmental perspective as both the esophagus and the pyloric sphincter are foregut derived structures. EA and IHPS are variable features in several (monogenetic) syndromes. This, and twin and familial studies, indicates a genetic component for both conditions as single entities. We hypothesized that genetic defects, disturbing foregut morphogenesis, are responsible for this combination of malformations. Non-genetic factors could also contribute, as mice exposed to Adriamycin develop EA and in utero diethylstilbestrol exposure is associated with EA.\n\nWe investigated the copy number profiles and protein coding variants of 15 patients with both EA and IHPS. As all parents were unaffected, we first considered dominant (de novo) or recessive inheritance models but could not identify putatively deleterious mutations or recessive variants. We did identify inherited variants in genes either known to be involved in EA or IHPS or important in foregut morphogenesis in all patients. Unfortunately, variant burden analysis did not show a significant difference with unaffected controls. However, the IHPS associated risk SNP rs1933683 had a significantly higher incidence (OR 3.29, p=0.009).\n\nAlthough the genetic variation in likely candidate genes as well as the predisposing locus near BARX1 (rs1933683) suggest a genetic component, it does not fully explain the abnormalities seen in these patients. Therefore, we hypothesize that a combination of high impact genetic, mechanical and environmental factors together can shift the balance to abnormal development.\n\nSummary statementInstead of one affected gene, the higher incidence of IHPS in EA patients is more likely the result of multiple (epi)genetic and environmental factors together shifting the balance to disease development.

genetics↗