• Applied Microscopy
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• v.25 no.1
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• pp.48-64
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• 1995

Ultrastructure of nerves and their associated cells in the bronchiolar epithelium of the human fetal lung were studied with ultrastructural and immunohistochemical methods. The neuroendocrine cells were scattered along the basal part of non-ciliated respiratory epithelium and appeared as single cell (solitary neuroendocrine cell) or groups (neuroepithelial bodies). The solitary neuroendocrine cells were devoid of any detectable innervation, while the neuroepithelial bodies were associated with nerve ending containing morphologically afferent (sensory) and efferent (motor) intraepithelial terminals. The afferent nerve endings contained abundant mitochondria with long cristae. The efferent nerve endings were characterized by the presence of synaptic vesicles. Both types of nerve endings formed synaptic junction between nerve endings and neuroepithelial bodies cells. Serial sections of the intraepithelial nerves revealed that both morphologically afferent and efferent types of nerve endings may be formed by the same nerve fiber. By immunohistochemistry, bombesin and serotonin were localized in solitary neuroendocrine cells and neuroepithelial bodies of human fetal lung from various prenatal age groups. These results suggest that the neuroepithelial bodies cells of the human fetal lung have neuroreceptor function.

• Applied Microscopy
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• v.29 no.1
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• pp.105-124
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• 1999

Histological and ultrastructural differentiations of the neuroepithelial cells in the mouse embryo during neurulation were observed. The neural plates and grooves consisted of pseudostratified columnar epithelium in the embryonic day (ED) 8 embryo were developed. In the ED 9 embryo, the neural tube was developed in all body length of embryo except both the cephalic and caudal ends. Secondary neurulation was shown at the tail bud of the ED 10 embryo. In the ED 8 embryo, the primitive streak was shown in the posterior end of the embryonic disc. The neuroepithelium, notochord and mesenchyme were well differentiated in the cephalic and cervical portions. In the ED 9 and 10 embryos, the roof plates of neural tubes were constituted of the closing of the surface ectodermal cells in the hindbrain and the neuroepithelial cells in the spinal cord. The floor plate of neural tube were consisted of the low pseudostratified columnar epithelium. The spinal motor nerve fibers were initially differentiated in the ED 10 embryo. According to the electron density of the cell and the differentiation of tell organelles, the neuroepithelial cells in the ED 9 and 10 embryos were classified into three types: dark, intermediate and light types. All types in the ED 9 embryo were observed but the dark cell in the ED 10 embryo was not done. The free ribosomes and polysomes in all neuroepithelial cells were developed. The RER and lipid droplets in the dark cell and the Golgi complex in the intermediate and light cells were observed. Many microfilaments in the cytoplasmic processes of intermediate cell and the microfilaments and microtubules in the light cell processes were observed to be well differentiated.

• International Journal of Stem Cells
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• v.17 no.1
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• pp.91-98
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• 2024

The development of in vitro models is essential in modern science due to the need for experiments using human material and the reduction in the number of laboratory animals. The complexity of the interactions that occur in living organisms requires improvements in the monolayer cultures. In the work presented here, neuroepithelial stem (NES) cells were differentiated into peripheral-like neurons (PLN) and the phenotype of the cells was confirmed at the genetic and protein levels. Then RNA-seq method was used to investigate how stimulation with pro-inflammatory factors such as LPS and IFN𝛾 affects the expression of genes involved in the immune response in human fibroblast-like synoviocytes (HFLS). HFLS were then cultured on semi-permeable membrane inserts, and after 24 hours of pro-inflammatory stimulation, the levels of cytokines secretion into the medium were checked. Inserts with stimulated HFLS were introduced into the PLN culture, and by measuring secreted ATP, an increase in cell activity was found in the system. The method used mimics the condition that occurs in the joint during inflammation, as observed in the development of diseases such as rheumatoid arthritis (RA) or osteoarthritis (OA). In addition, the system used can be easily modified to simulate the interaction of peripheral neurons with other cell types.

• Applied Microscopy
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• v.23 no.1
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• pp.109-124
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• 1993

The prenatal development of thoracic spinal cord was studied by electron microscope in human embryos and fetuses ranging from 9mm to 260mm crown-rump length (5-30 weeks of gestational age). Ependymal cells in all fetal ages had conspicuous junctional complexes close to the lumen of the central canal into which microvilli and cilia projected. The ependymal cells contained numerous longitudinally arranged mitochondria, flattened cisternae of endoplasmic reticulum and Golgi complex. At 20 mm embryo, the floor and roof plates were composed of ependymoglial cells and undifferentiated neuroepithelial cells. The neuroepithelia of the sacral spinal cord were delineated from central medullary cord. By 100 mm fetus few undifferentiated neuroepithelial cells remained in the floor and roof plates. At 150 mm fetus, the whole central canal was formed by ciliated columnar epithelial cells containing cilia with basal bodies. The microvilli became tangled and club-shaped and formed a matted surface. The canal was filled with areas of dark and pale amorphous materials bounded by membrane-like structure. These two types of material were found throughout the whole central canal from 100 mm fetus onwards. By 260 mm fetus, microfibrils were first observed in the ependymal cells. In conclusion, it seems that early development and differentiation of central canal ependyma are simlar to that in other part of the brain ventricular system although ependymoglial cells are more prominent.

• Molecules and Cells
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• v.41 no.4
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• pp.257-263
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• 2018

Vertebrate organ development is accompanied by demarcation of tissue compartments, which grow coordinately with their neighbors. Hence, perturbing the coordinative growth of neighboring tissue compartments frequently results in organ malformation. The growth of tissue compartments is regulated by multiple intercellular and intracellular signaling pathways, including the Hippo signaling pathway that limits the growth of various organs. In the optic neuroepithelial continuum, which is partitioned into the retina, retinal pigment epithelium (RPE) and ciliary margin (CM) during eye development, the Hippo signaling activity operates differentially, as it does in many tissues. In this review, we summarize recent studies that have explored the relationship between the Hippo signaling pathway and growth of optic neuroepithelial compartments. We will focus particularly on the roles of a tumor suppressor, neurofibromin 2 (NF2), whose expression is not only dependent on compartment-specific transcription factors, but is also subject to regulation by a Hippo-Yap feedback signaling circuit.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.9-17
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• 2001

It has been demonstrated that multipotent neuronal progenitor cells can be isolated from the developing or adult CNS and proliferated in vitro in response to epidermal growth factor. The present study was undertaken to investigate the differentiation of neuronal progenitor cells after transplantation into the neonatal rat forebrain striatum. Primary cultured progenitor cells were labeled with 3,3'-dioctadecycloxacarbonyl- amine perchlorate (DiO). DiO labeled progenitor cells were implanted into neonatal rat striatum. Implanted DiO labeled progenitor cells were differentiated into astrocytes and GABAergic neurons. These results suggest that implanted progenitor cells can be differentiated into neurons in host forebrain striatum. In addition, our data show that DiO labeling is a useful technique for tracing implanted progenitor cells.

• Journal of Chest Surgery
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• v.25 no.8
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• pp.806-811
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• 1992

The primary neuroendocrine carcinomas[NEC] of the lung are relatively rare. There are classified histologically into the following groups. 1] bronchial carcinoid, 2] well differentiated neuroendocrine carcinoma[WDNC], 3] intermediate cell neuroendocrine carci-noma[ICNC], 4] small cell neuroendocrie carcinoma[SCNC]. The NE cells can be found throughout the mucosa of the bronchial tree by the electron microscopy. By the immunocytochemistry, Neuron-specific enolase[NSE], serotonin, born-csin, and calcitonin are found in normal solitary NE cells and neuroepithelial bodies. The immunohistochemistry has the advantage that it can be applied on routine pathology specimens. The NSE was localized in all of the NE granule bearing tumors but also present in 57 per cent of the non NE carcinomas. Together the combination of chromogranin A, bombesin and NSE should provide an exellent signature for tumor cells expressing NE features, such as carcinoids and other NE carcinomas. We have experienced two cases of primary pulmonary NEC in 59 and 29 years old men. The former was admitted due to exertional dyspnea and left chest pain, the latter, newly developed mass on chest X-ray. They were treated by Lt pneumonectomy with LN dissection and RLL resection with LN dissection The postoperative diagnoses were could be confirmed by NSE study as NEC which were SCNEC and INEC in subgroups. The postoperative courses were uneventful.

• Molecules and Cells
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• v.37 no.1
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• pp.59-65
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• 2014

Eph receptors and their ligands ephrins have been implicated in guiding the directed migration of neural crest cells (NCCs). In this study, we found that Wnt1-Cre-mediated expression of ephrinA5-Fc along the dorsal midline of the dien- and mesencephalon resulted in severe craniofacial malformation of mouse embryo. Interestingly, expression of cephalic NCC markers decreased significantly in the frontonasal process and branchial arches 1 and 2, which are target areas for the migratory cephalic NCCs originating in the dien- and mesencephalon. In addition, these craniofacial tissues were much smaller in mutant embryos expressing ephrinA5-Fc. Importantly, EphA7-positive cephalic NCCs were absent along the dorsal dien- and mesencephalon of mutant embryos expressing ephrinA5-Fc, suggesting that the generation of cephalic NCCs is disrupted due to ephrinA5-Fc expression. NCC explant experiments suggested that ephrinA5-Fc perturbed survival of cephalic NCC precursors in the dorsal midline tissue rather than affecting their migratory capacity, which was consistent with our previous report that expression of ephrinA5-Fc in the dorsal midline is responsible for severe neuroepithelial cell apoptotic death. Taken together, our findings strongly suggest that expression of ephrinA5-Fc decreases a population of cephalic NCC precursors in the dorsal midline of the dien- and mesencephalon, thereby disrupting craniofacial development in the mouse embryos.

• Advances in pediatric surgery
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• v.9 no.2
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• pp.94-97
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• 2003

The teratoma is a unique complex neoplasm and is one of the most frequent pediatric tumors originated from the extragonadal germ cells. Mature teratoma is composed of mature differentiated tissues, while immature teratoma always contains embryonic tissues of variable degrees of immaturity, especially in the neuroepithelial elements. Diagnosis of teratoma is relatively easy by conventional radiologic study, but the immaturity can be identified only by histopathological examination. Between January 1993 to December 2002, 63 cases of teratoma were operated and analysed retrospectively at the Chonnam University Hospital Female to male ratio was about 3:1 and age distribution was relatively even. Among 63 cases, gonadal teratoma was the most common (52.4%), followed by sacrococcygeal (25.4%), retroperitoneal (9.5%) and mediastinal teratoma (9.5%). Fifty-six cases were mature teratomas and seven were immature teratomas. Alpha-fetoprotein (AFP) was elevated in 4 of 6 immature cases, but in 2 of 51 mature ones Elevated AFP progressively returned to normal range by 1 month after operation in all. Complete excision of the mass was performed, and major complication was not noticed. In five immature cases, PEB chemotherapy (Cisplatin, Etoposide, Bleomycin) was performed. Two of 2 cases in histological grade II were well tolerated to the aggressive chemotherapy. One of three cases in grade III expired due to severe bone marrow depression, and two of them expired by tumor recurrences. In conclusion, immature teratoma in histological grade III showed high potentiality of recurrence. Therefore, postoperative chemotherapy has to be applied to the high graded immature tumors.