Novel heterozygous pathogenic variants in CHUK in a patient with AEC-like phenotype, immune deficiencies and 1q21.1 microdeletion syndrome: a case report
BMC MEDICAL GENETICS
Authors: Cadieux-Dion, Maxime; Safina, Nicole P.; Engleman, Kendra; Saunders, Carol; Repnikova, Elena; Raje, Nikita; Canty, Kristi; Farrow, Emily; Miller, Neil; Zellmer, Lee; Thiffault, Isabelle
Abstract
Background: Ectodermal dysplasias (ED) are a group of diseases that affects the development or function of the teeth, hair, nails and exocrine and sebaceous glands. One type of ED, ankyloblepharon-ectodermal defects-cleft lip/palate syndrome (AEC or Hay-Wells syndrome), is an autosomal dominant disease characterized by the presence of skin erosions affecting the palms, soles and scalp. Other clinical manifestations include ankyloblepharon filiforme adnatum, cleft lip, cleft palate, craniofacial abnormalities and ectodermal defects such as sparse wiry hair, nail changes, dental changes, and subjective hypohydrosis. Case presentation: We describe a patient presenting clinical features reminiscent of AEC syndrome in addition to recurrent infections suggestive of immune deficiency. Genetic testing for TP63, IRF6 and RIPK4 was negative. Microarray analysis revealed a 2 MB deletion on chromosome 1 (1q21.1q21.2). Clinical exome sequencing uncovered compound heterozygous variants in CHUK; a maternally-inherited frameshift variant (c.1365del, p.Arg457Aspfs*6) and a de novo missense variant (c.1388C > A, p.Thr463Lys) on the paternal allele. Conclusions: To our knowledge, this is the fourth family reported with CHUK-deficiency and the second patient with immune abnormalities. This is the first case of CHUK-deficiency with compound heterozygous pathogenic variants, including one variant that arose de novo. In comparison to cases found in the literature, this patient demonstrates a less severe phenotype than previously described.
Characterization of Human Dental Pulp Cells-Derived Spheroids in Serum-Free Medium: Stem Cells in the Core
JOURNAL OF CELLULAR BIOCHEMISTRY
Authors: Xiao, Li; Tsutsui, Takeki
Abstract
Spheroid models have led to an increased understanding of differentiation, tissue organization and homeostasis. In the present study, we have observed that under a serum-free medium, human dental pulp cells (DPCs) spontaneously formed spheroids, and could survive over 15 weeks. To characterize these spheroids, we investigated their dynamics, microenvironment, cell distribution, molecular profiles, and neuronal/osteogenic potential. Cell tracking assay showed that cells inside the spheroids have very slow cycling. Although the spheroids had hypoxia microenvironments, there were not any massive cell die-offs even after long-term cultivation. Whole mount immunofluorescence staining and histological analysis showed a distribution of stem cells in the central/intermediate zones of spheroids. qRT-PCR analysis demonstrated that the expression of stemness markers NANOG, TP63, and CD44 in the spheroids were much higher than within the monolayer cultures. Gene expression levels of neural markers CDH2, NFM, TUBB3, and CD24 in the spheroids were much higher than the monolayer DPCs and increased in a culture time-dependent manner. Without any neural induction, spheroid-derived cells spontaneously converted into neuron-like cells with positive staining of neural markers HuC/D and P75 under the serum-free medium for about 2 weeks. When the spheroids were transferred into osteogenic medium, they rapidly differentiated into osteo/odontogenic cells, especially the central original cells. Compared to the monolayer DPCs, mineralization in spheroids were significantly increased. This spheroid model offers a study tool to explore the molecular bases of stem cell homeostasis and tissue organization, and can be wildly used for nerve tissue and bone regeneration. J. Cell. Biochem. 114: 2624-2636, 2013. (c) 2013 Wiley Periodicals, Inc.