Reflecting the human lip in vitro: Cleft lip skin and mucosa keratinocytes keep their identities.

OBJECTIVES: Cell models have shown great promise as tools for research, potentially providing intriguing alternatives to animal models. However, the original tissue characteristics must be maintained in culture, a fact that is often assumed, but seldom assessed. We aimed to follow the retention of the original tissue identities of cleft lip-derived skin and mucosa keratinocytes in vitro. METHODS: Cleft lip-derived keratinocytes were isolated from discarded tissue along the cleft margins during cheiloplasty. Cell identities were assessed by immunohistochemistry and quantitative real-time PCR for tissue-specific markers and compared with native lip tissue. Moreover, keratinocytes were regularly analyzed for the retention of the original tissue characteristics by the aforementioned methods as well as by differentiation assays. RESULTS: The various anatomical zones of the human lip could be distinguished using a panel of differentiation and functional-based markers. Using these markers, retention of the original tissue identities could be followed and confirmed in the corresponding primary keratinocytes in culture. CONCLUSIONS: Our findings promote patient-derived cells retaining their original identities as astonishing and clinically relevant in vitro tools. Such cells allow a better molecular understanding of various lip-associated pathologies as well as their modeling in vitro, including but not restricted to orofacial clefts.

Postoperative Dysnatremia in Pediatric Patients Undergoing Palatoplasty.

OBJECTIVE: Identifying predisposing factors to dysnatremia to improve perioperative care after cleft surgery. DESIGN: Retrospective case series. Patient data were obtained through the electronic medical records of the hospital. SETTING: Tertiary care university hospital. PATIENTS: The inclusion criterion was the measurement of an abnormal natremia value, defined as Na >150 or <130 mmol/l after a cleft lip or cleft palate repair procedure. The exclusion criterion was natremia between 131 and 149 mmol/l. RESULTS: Natremia measurements were available for 215 patients born between 1995 and 2018. Five patients presented with postoperative dysnatremia. Several predisposing factors to dysnatremia have been identified: drugs, infection, administration of intravenous fluids, and postoperative syndrome of inappropriate antidiuretic hormone secretion. Although the hospital environment contributes to dysnatremia development, the fact that only patients undergoing cleft palate repair develop natremia anomalies suggests that this surgery may be itself a risk factor. CONCLUSION: Children undergoing palatoplasty may be at higher risk to develop postoperative dysnatremia. Early recognition of symptoms and risk factors, postoperative monitoring, and prompt treatment of dysnatremia diminish the risk of neurological complications.

Discovery and characterization of heterogeneous and multipotent fibroblast populations isolated from excised cleft lip tissue.

BACKGROUND: Regularly discarded lip tissue obtained from corrective surgeries to close the cleft lip represents an easily accessible and rich source for the isolation of primary fibroblasts. Primary fibroblasts have been described to show compelling similarities to mesenchymal stem cells (MSCs). Hence, cleft lip and palate (CLP) lip-derived fibroblasts could be thought as an intriguing cell source for personalized regenerative therapies in CLP-affected patients. METHODS: Initially, we thoroughly characterized the fibroblastic nature of the lip-derived mesenchymal outgrowths by molecular and functional assays. Next, we compared their phenotype and genotype to that of bone marrow-mesenchymal stem cells (BM-MSCs) and of human lung-derived fibroblasts WI38, by assessing their morphology, surface marker expression, trilineage differentiation potential, colony-forming (CFU) capacity, and immunomodulation property. Finally, to better decipher the heterogeneity of our CLP cultures, we performed a single cell clonal analysis and tested expanded clones for surface marker expression, as well as osteogenic and CFU potential. RESULTS: We identified intriguingly similar phenotypic and genotypic properties between CLP lip fibroblasts and BM-MSCs, which makes them distinct from WI38. Furthermore, our own data in combination with the complex anatomy of the lip tissue indicated heterogeneity in our CLP cultures. Using a clonal analysis, we discovered single cell-derived clones with increased levels of the MSC markers CD106 and CD146 and clones with variabilities in their commitment to differentiate into bone-forming cells and in their potential to form single cell-derived colonies. However, we were not able to gain clones possessing superior MSC-like capacities when compared to the heterogeneous parental CLP population. Additionally, all clones could still generate contractile forces and retained robust levels of the fibroblast specific marker FSP1, which was not detectable in BM-MSCs. CONCLUSIONS: Our results suggest that we isolate heterogeneous populations of fibroblasts from discarded CLP lip tissue, which show a prominently multipotent character in their entirety avoiding the need for elaborate subpopulation selections in vitro. These findings suggest that CLP lip fibroblasts might be a novel potential cell source for personalized regenerative medicine of clinical benefit for CLP patients.

A Living Cell Repository of the Cranio-/Orofacial Region to Advance Research and Promote Personalized Medicine.

The prevalence of congenital anomalies in newborns is estimated to be as high as 6%, many of which involving the cranio-/orofacial region. Such malformations, including several syndromes, are usually identified prenatally, at birth, or rarely later in life. The lack of clinically relevant human cell models of these often very rare conditions, the societal pressure to avoid the use of animal models and the fact that the biological mechanisms between rodents and human are not necessarily identical, makes studying cranio-/orofacial anomalies challenging. To overcome these limitations, we are developing a living cell repository of healthy and diseased cells derived from the cranio-/orofacial region. Ultimately, we aim to make patient-derived cells, which retain the molecular and genetic characteristics of the original anomaly or disease in vitro, available for the scientific community. We report our efforts in establishing a human living cell bank derived from the cranio-/orofacial region of otherwise discarded tissue samples, detail our strategy, processes and quality checks. Such specific cell models have a great potential for discovery and translational research and might lead to a better understanding and management of craniofacial anomalies for the benefit of all affected individuals.

A Novel Van der Woude Syndrome-Causing IRF6 Variant Is Subject to Incomplete Non-sense-Mediated mRNA Decay Affecting the Phenotype of Keratinocytes.

Van der Woude syndrome (VWS) is a genetic syndrome that leads to typical phenotypic traits, including lower lip pits and cleft lip/palate (CLP). The majority of VWS-affected patients harbor a pathogenic variant in the gene encoding for the transcription factor interferon regulatory factor 6 (IRF6), a crucial regulator of orofacial development, epidermal differentiation and tissue repair. However, most of the underlying mechanisms leading from pathogenic IRF6 gene variants to phenotypes observed in VWS remain poorly understood and elusive. The availability of one VWS individual within our cohort of CLP patients allowed us to identify a novel VWS-causing IRF6 variant and to functionally characterize it. Using VWS patient-derived keratinocytes, we reveal that most of the mutated IRF6_VWS transcripts are subject to a non-sense-mediated mRNA decay mechanism, resulting in IRF6 haploinsufficiency. While moderate levels of IRF6_VWS remain detectable in the VWS keratinocytes, our data illustrate that the IRF6_VWS protein, which lacks part of its protein-binding domain and its whole C-terminus, is noticeably less stable than its wild-type counterpart. Still, it maintains transcription factor function. As we report and characterize a so far undescribed VWS-causing IRF6 variant, our results shed light on the physiological as well as pathological role of IRF6 in keratinocytes. This acquired knowledge is essential for a better understanding of the molecular mechanisms leading to VWS and CLP.

Sella turcica morphometrics in children with unilateral cleft lip and palate.

OBJECTIVE: To use morphometric methods to investigate the size and shape of the sella turcica in children with unilateral cleft lip and palate (UCLP). SETTING AND SAMPLE POPULATION: Fifty-six healthy children with non-syndromic UCLP, from a major paediatric teaching hospital, with lateral cephalograms taken prior to alveolar bone grafting, were compared with an age- and sex-matched control group of healthy children without orofacial clefts, with lateral cephalograms taken prior to orthodontic treatment. MATERIALS AND METHODS: In this cross-sectional study, conventional measurements were performed on the sella turcica to measure width, height and area on lateral cephalograms. Sella shape was also analysed using 11 points defining the sella turcica contours, using geometric morphometrics. Procrustes superimposition was used to register all sella contour tracings to calculate average sella shape. Principal component analysis was applied to the residuals of the point coordinates, and principal components (PCs) of shape were extracted. RESULTS: Statistically significant differences between the UCLP and control groups were found for sella posterior height, midpoint height, maximum height and area, where all of these were smaller in children with UCLP. Principal component analysis revealed that the first two PCs accounted for 84.7% of total shape variance. There was a statistically significant difference in sella shape between children with UCLP and control children. CONCLUSIONS: In children with UCLP, the sella turcica is shorter and with a smaller surface area when compared to matched non-cleft children. Moreover, sella turcica shape, when disregarding size, seems to differ to that of non-cleft children.

Prevalence of bifid uvula in primary school children.

BACKGROUND: A bifid uvula is an anatomic variation that can be predictive of sub-mucous cleft palate, which may cause velopharyngeal insufficiency (VPI). Bifid uvula prevalence in the literature ranges from 0.18% to 10.3%, depending on the population studied. The aim of this study is to determine the prevalence of bifid uvula in the Geneva's school children population. METHODS: A cross-sectional study was conducted in Geneva's primary school children, from September 2014 to June 2015. An examination of the uvula was performed by dentists working for the Scholastic Dental Service, after a specific training in diagnosing bifid uvulas. The dentists recorded their findings on a standardized form. RESULTS: The total number of school children in Geneva in the school year 2014-2015 was 30,375. 23,961 children had their uvula examined, representing 79% of the total population of school children. Among them, a hundred school children had a cleft uvula. One schoolgirl had no uvula. The prevalence of bifid uvula is 0.42%. Sex ratio (M/F) is 0.96. DISCUSSION: This large study, the second in literature for number of patients examined, identified a prevalence of bifid uvula of 0.42%. This result is in agreement with previous studies.

Multiple arteriovenous malformations caused by RASA1 gene mutation presenting during pregnancy - a case report and review of the literature.

Pregnancy can influence the development and progression of congenital arteriovenous malformations (AVM) and thus lead to life-threatening complications for the mother and fetus like high output cardiac failure and premature delivery. The simultaneous presence of a capillary malformation and AVM strongly suggests a RASA1 related disorder. Keywords: Arteriovenous malformations, capillary malformation-arteriovenous malformation, capillaries/abnormalities, port-wine stain, pregnancy, RASA1 protein.

Keratinocytes Isolated From Individual Cleft Lip/Palate Patients Display Variations in Their Differentiation Potential in vitro.

To gain more understanding of the complex molecular processes underlying cleft lip/palate (CLP), we established a unique human cell bank, consisting of keratinocytes and corresponding fibroblasts from individual CLP patients as a new study tool. After their careful characterization, we used such patient-derived cell cultures as well as control keratinocytes for in vitro differentiation and proliferation assays. Foreskin-derived control cells as a group showed significant higher induction of the late differentiation markers Loricrin and Filaggrin than the group of CLP patients-derived keratinocytes. Additionally, we detected great variations between individual CLP keratinocyte cell cultures in regard to their potential to terminally differentiate as assessed by the induction of Loricrin and Filaggrin. Primary patient cell cultures that did not properly differentiate, exhibited high proliferation rates. Moreover, we could correlate the expression levels of transcription factor IRF6 to the ability of individual cell cultures to terminally differentiate. Using clinically relevant, patient-derived cells, our results suggest that some of the genetic predispositions causing CLP might also lead to deficiencies in keratinocyte differentiation manifested in in vitro assays.

Skin-Sparing Débridement for Necrotizing Fasciitis in Children.

BACKGROUND: Necrotizing fasciitis is a serious soft-tissue infection associated with sepsis and tissue destruction. Surgical management usually requires extensive débridement of necrotic fascia and overlying skin, with significant aesthetic and functional consequences. The authors review the outcome of all recent cases of necrotizing fasciitis treated with skin-sparing débridement at their institution. METHODS: The authors conducted a retrospective review of all of their cases of necrotizing fasciitis treated with skin-sparing débridement. Medical records were evaluated with a standard form gathering relevant demographic and clinical data. All cases were confirmed as necrotizing fasciitis histologically. RESULTS: Ten patients were admitted with a diagnosis of necrotizing fasciitis. The median age of the patients was 4.9 years (range, 1.7 to 15.1 years). The majority of initial lesions were caused by chickenpox, mostly on the trunk. Interval from admission to surgery was 6 hours (range, 1 to 27.5 hours), with a median hospital stay of 11 days (range, 5 to 43 days). Median fasciectomy was 2.5 percent (range, 1 to 15 percent) of total body surface area, with a median skin excision of 0.25 percent of total body surface area (range, 0.1 to 3 percent). All patients received intravenous amoxicillin/clavulanic acid plus clindamycin. Delayed direct closure was possible for all patients. Median follow-up was 17 months (range, 3 to 79 months). There was no death in this series. CONCLUSION: This surgical management restricts skin excision to the area of definite skin necrosis, limiting skin excision to one-tenth of excised fascia, with long-term favorable cosmetic and functional results. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Local hemodynamic effects of radiation on the rabbit orbitozygomatic complex with and without cytoprotection.

BACKGROUND: The authors have previously demonstrated that radiation-induced craniofacial bone growth inhibition may be ameliorated using the known cytoprotectant amifostine in the infant rabbit orbitozygomatic complex. The authors' hypothesis is that reduction in blood supply plays an important role in inhibiting craniofacial bone growth following radiotherapy and that cytoprotective pretreatment exerts its protective effect by maintaining blood supply. METHODS: Seven-week-old New Zealand male infant rabbits underwent single-dose orthovoltage irradiation to the right orbitozygomatic complex using established protocols: 0 Gy (sham), 35 Gy, and 35 Gy following pretreatment with amifostine (300 mg/kg administered intravenously). Blood flow to the orbitozygomatic complex, orbitozygomatic complex periosteum, masseter, hemimandible, and overlying skin was measured 1, 14, and 63 days after irradiation, using the modified 15-µm radioactive microsphere technique (n = 18 per group, n = 6 per time point). Orbitozygomatic complex bone specimens were harvested for blood vessel morphometry using safranin O stains at days 1 and 100 after irradiation (n = 20 per group, n = 10 per time point). RESULTS: Blood flow to the irradiated orbitozygomatic complex was significantly (p < 0.05) greater 1 day after single-dose orthovoltage irradiation compared with nonirradiated controls. This increase was not observed in the amifostine-pretreated animals and was also not seen 14 and 63 days after irradiation. No histomorphometric vessel changes were detected at any time point after irradiation in this study. CONCLUSIONS: Single-dose orthovoltage irradiation results in a temporary elevation in regional blood flow to the orbitozygomatic complex, returning to control levels within 14 days. Although pretreatment with amifostine attenuates this response, radiation-induced craniofacial bone growth inhibition in this model does not appear to be secondary to hemodynamic alterations.

Radiation-induced craniofacial bone growth inhibition: acute and long-term effects on bone histopathology with and without cytoprotection.

BACKGROUND: The authors previously established an animal model of radiation-induced craniofacial bone growth inhibition and demonstrated the effectiveness of cytoprotection in preserving growth using amifostine, but the mechanism is unclear. The objective of this study was to investigate the acute and long-term histopathologic effects of single-dose orthovoltage irradiation on craniofacial bone with and without cytoprotection. METHODS: Sixty infant New Zealand White rabbits (7-week-old) were randomized into three groups (n = 20 per group): group 1, 0-Gy, sham irradiation; group 2, 35-Gy single-dose orthovoltage irradiation; and group 3, cytoprotection with amifostine before irradiation. Orbitozygomatic complex bone was harvested from animals 12 hours after irradiation and at skeletal maturity (21 weeks of age). Histologic parameters measured included native bone cell (osteoblast, osteoclast, and osteocyte) populations, periosteal proliferation indices (MIB-1 stains), bone turnover rates [triple fluorochromes: tetracycline administered at 7 weeks of age (before irradiation), alizarin complexone at 12 weeks, and calcein at 16 weeks of age], and endosteal space fibrosis levels. RESULTS: Orthovoltage irradiation significantly (p < 0.05) reduced osteoblast and osteoclast counts 12 hours after irradiation (age, 7 weeks) with or without pretreatment with amifostine but had no effect on osteocyte populations. Long-term analysis at age 21 weeks demonstrated significantly (p < 0.05) increased osteoblast counts, reduced endosteal space fibrosis, reduced periosteal proliferation indices, and improved bone turnover (fluorochrome stains) in amifostine-treated animals. CONCLUSION: This study suggests that amifostine cytoprotection is mediated through a combination of reduced cellular injury with enhanced promotion of cellular bone rebuilding potential.

Infected urocolpos and generalized peritonitis secondary to labia minora adhesions.

INTRODUCTION: Labia minora adhesions (LMA) are a common finding in young girls. Usually, this condition is asymptomatic and spontaneously disappears during adolescence. We report on a case revealed by infected urocolpos and peritonitis and whose treatment finally required surgical reduction labioplasty. CASE REPORT: A 9-year-old girl presented with a 2-day history of abdominal pain and fever. Urinary continence had never been obtained, with diurnal leaks. Physical examination showed signs of peritoneal irritation and a subtotal vulvar obstruction due to LMA. At surgery, after LMA lysis, a large amount of cloudy urine-like fluid emptied under pressure from the vagina. Laparoscopy showed generalized peritonitis without any intraabdominal cause. The same Escherichia coli was identified in the infected urocolpos and the abdominal fluid. Postoperative course was uneventful. Because of recurrent LMA, the patient underwent several courses of local estrogen therapy. Labia minora hypertrophy with LMA developed 2 years after peritonitis, requiring surgical reduction labioplasty. We used a new technique with interposition of skin flaps. The girl is now well, without LMA or infection, 4 years after labioplasty. CONCLUSION: Although rare, subtotal vulvar obstruction because of LMA may lead to infected hydrocolpos and peritonitis. Recurrent LMA may necessitate surgical labioplasty.

Radiation-induced craniofacial bone growth inhibition: in vitro cytoprotection in the rabbit orbitozygomatic complex periosteum-derived cell culture.

BACKGROUND: Radiotherapy for the management of head and neck cancer in pediatric patients results in severe inhibition of craniofacial bone growth. Previously, the infant rabbit orbitozygomatic complex was established as an experimental model. Amifostine, a cytoprotective agent, was found effective in preventing radiation-induced bone growth inhibition. This study was designed to investigate the effects radiation on osteogenic cells from infant rabbit orbitozygomatic complex periostea and to assess the effects of cytoprotection in vitro. METHODS: Infant New Zealand White rabbits (n = 18) were randomized into three groups and received radiation (0, 10, or 15 Gy) to both orbitozygomatic complexes. Cell cultures were developed from orbitozygomatic complex periostea, and cell numbers, proliferation, alkaline phosphatase, and collagen type I expression and mineralization were assessed. Subsequently, rabbits (n = 18) were randomized into three groups to receive either radiation at the effective dose, pretreatment with amifostine (300 mg/kg, intravenously, 20 minutes before irradiation) with the effective radiation dose, or no treatment. Cell cultures were developed and tested for proliferation and alkaline phosphatase expression. RESULTS: Irradiation resulted in a significant inhibition of cell numbers (p < 0.001) and proliferation (p < 0.01) at the 15-Gy dose and no statistically significant changes in alkaline phosphatase activity. Collagen type I expression and mineralization were also significantly reduced at the 15-Gy dose. Pretreatment with amifostine significantly (p < 0.05) enhanced the number of surviving cells. CONCLUSIONS: Amifostine is capable of protecting orbitozygomatic complex periosteum-derived osteogenic cells from the deleterious effects of radiation. This study provides the basis for understanding the cellular mechanisms of radiation-induced craniofacial bone growth inhibition and cytoprotection by amifostine.

Radioprotection of craniofacial bone growth.

In this review, the potential of pharmacologic therapy for prevention of radiation-induced bone growth inhibition is discussed. Significant radioprotection using the radioprotector Amifostine has been achieved in animal models of radiation-induced retardation of long and craniofacial bone growth. Moreover, radioprotection in vitro has been achieved in a number of cell lines, including osteoblast-like, endothelial, and fibroblastic. This evidence may support future clinical investigations of radioprotector Amifostine or similar substances for radioprotection of the growing craniofacial skeleton.

Radiation-induced craniofacial bone growth disturbances.

Multimodality treatment, including radiotherapy, chemotherapy, and surgery, is required for the management of head and neck cancer in pediatric patients. Despite the modern advances in radiation dosing and targeting techniques, the radiation damage to the growing craniofacial skeleton in children remains a significant clinical problem. The first part of this review summarizes the clinical effects of radiotherapy on craniofacial bone growth in children. Experimental evidence on therapeutic radiation effects on bone growth in in vivo and in vitro models is reviewed. The second part of this review focuses on prevention of radiation-induced craniofacial bone growth inhibition using radioprotective agents.

An in vitro model of radiation-induced craniofacial bone growth inhibition.

Radiation-induced craniofacial bone growth inhibition is a consequence of therapeutic radiation in the survivors of pediatric head and neck cancer. Previously, the infant rabbit orbitozygomatic complex (OZC) was established as a reliable animal model. The purpose of this study was to develop a cell culture model from the rabbit OZC to study the effects of radiation in the craniofacial skeleton. Infant (7-week-old) New Zealand white rabbits were used in this study. Periostea from both OZC were harvested in sterile conditions, introduced into cell culture by way of sequential digestion, and subcultured at confluence. Cultures were analyzed for cellular proliferation (methylthiazoletetrazolium assay), alkaline phosphatase activity, collagen type I expression, and mineralization. Electron microscopy was performed to reveal the in vitro ultrastructure. Subsequently, rabbits were irradiated with sham or 15 Gy radiation, and cell cultures were developed and analyzed for cell numbers. Cell cultures, grown from OZC periostea, expressed osteoblast-like phenotype, with high alkaline phosphatase activity, collagen type 1 expression, and mineralization in an osteogenic environment. Electron microscopy confirmed the characteristic ultrastructural features of osteogenesis in vitro. Finally, significantly (P < 0.01) fewer cells were obtained from animals treated with 15 Gy radiation compared with those from control animals.A primary cell culture with osteoblast-like cellular phenotype was developed from infant rabbit OZC periosteum. This cell culture system responded to in vivo administered radiation by a significant decrease in cell numbers. This in vitro model will be subsequently used to study the cellular mechanisms of radiation and radioprotection in craniofacial osteoblast-like cells.