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Islet Transplantation in Type 1 Diabetes: Stem Cell Research and Therapy
Published in Debarshi Kar Mahapatra, Sanjay Kumar Bharti, Medicinal Chemistry with Pharmaceutical Product Development, 2019
After the pancreatic epithelium growth and proliferation, Notch signaling is inhibited in some epithelial cells, allowing the expression of pro-endocrine gene Neurogenin-3 (Ngn3) [35]. Ngn3 is expressed in all endocrine progenitor cells, which initiates a cascade of transcription factor expression which, in turn, initiates differentiation of endocrine cells. This cascade includes Nkx2-2, Neurod–1, Nkx6-1, Pax6, Pax4, and Isl1.
Cell Populations Isolated from Amnion, Chorion, and Wharton’s Jelly of Human Placenta
Published in Ornella Parolini, Antonietta Silini, Placenta, 2016
Francesco Alviano, Roberta Costa, Laura Bonsi
hAECs are also able to differentiate into pancreatic cells. Wei et al. (2003) demonstrated that amniotic epithelial cells, cultured in presence of specific molecules, expressed insulin and were also able to normalize levels of serum glucose in diabetic mice for several months. Later, other research groups demonstrated that hAECs, when cultured in pancreatic differentiation medium, expressed pancreatic α and β cell markers, including transcription factors PDX1 (pancreatic duodenum homeobox 1), PAX6 (paired box homeotic gene 6), and NKX2.2 (NK2 transcription factor-related locus 2), and markers of pancreatic endocrine cells such as insulin and glucagon (Miki et al. 2005). Ilancheran et al. (2007) also investigated ultrastructural organization of differentiated hAECs, similar to exocrine beta-acinar cells.
Endocrine Glands
Published in Pritam S. Sahota, James A. Popp, Jerry F. Hardisty, Chirukandath Gopinath, Page R. Bouchard, Toxicologic Pathology, 2018
Richard A. Peterson, Sundeep Chandra, Mark J. Hoenerhoff
The multiple cell types of the pancreatic islets of Langerhans (pancreatic islets) are incorporated into a “sea” of exocrine pancreatic tissue. In mammals, the endocrine tissue (islets) comprises <5% and the exocrine tissue comprises the remaining >95% of the pancreas. In all mammals, the pancreas is located on the left side of the peritoneal cavity, between the spleen and the pyloric region of the stomach. The pancreas runs along the duodenum and terminates within the mesentery/omentum. The pancreas generally consists of poorly demarcated areas referred to as the body and tail, but there is substantial interspecies variation, and the anatomic terminology varies as well. The distribution and number of islets differ between the areas of the pancreas and between species. During embryonal development, the pancreas arises from the duodenal endoderm (develops into the dorsal that then fuses to form the developing pancreas). The mature pancreas consists primarily of the acinar tissue, which is discussed elsewhere in this book, and the pancreatic islets (Islets of Langerhans), which arise multifocally by budding off of the developing acini and undergo a genetic switch to synthesizing certain protein hormones such as insulin, glucagon, pancreatic polypeptide, ghrelin, and somatostatin (Carlson 1988). The pancreatic islet cells develop through a series of differentiation steps, from primary multipotential progenitor cells that divide to form secondary multipotential precursor cells, which can then differentiate into acinar and bipotential progenitor cells. The bipotential progenitor cells differentiate into ductular cells and endocrine precursor cells. The endocrine precursor cells then undergo a series of cellular divisions and differentiation steps to an endocrine precursor cell, which, depending on the presence of certain transcription factors, will differentiate into α-, δ-, ε-, pancreatic peptide (PP)-, or immature β-cells. Immature β-cells will then differentiate into mature β-cells in the presence of the following transcription factors: Pdx1HI, Mnx1, Nkx6.1, NeuroD, Nkx2.2, MafA, Pax4, Foxa1, and Foxa2 (Pan and Wright 2011).
Ewing Sarcoma Displaying Extensive Well Differentiated Neuroblastomatous Differentiation: A Case Report
Published in Fetal and Pediatric Pathology, 2023
Nil Çomunoğlu, Cem Çomunoğlu, Rahşan Özcan, Süheyla Ocak
There are few reports of neurophil with varying degrees of ganglionic differentiation. In this presented case this component was prominent. Historically these tumors were named as “Peripheral neuroepithelioma/Malignant peripheral neuroectodermal tumor” including the so-called “Askin Tumor”. It has been claimed that the origin of these tumors might have been the migrating neural crest cells during embryogenesis [12]. This theory may explain the existence of ganglion cells in these tumors. As one of the two major neuroectodermal tumor group, ESs can be included in the same family with the other tumor group, neuroblastomas, which differentiate along the autonomic nerve cell lineage [7]. Well differentiated neuroblastomatous differentiation in ES cases may pose important diagnostic problems as in this case. Recognition of such feature may prevent a possible misinterpretation and a failure in oncologic treatment. Immunohistochemical markers are important in differential diagnosis. NKX2.2 is sensitive and moderately specific for ES [15]. CD99 is almost always immunopositive in diffuse and strong membranous staining pattern. FLI-1 and ERG are other positive staining helpful immunohistochemical markers. ES cases have FET::ETS fusion. t(11;22)(q24;q12) translocation resulting in EWSR1::FLI1 fusion and the t(21;22)(q22;q12) translocation resulting in EWSR1::ERG fusion are detected in most ES cases [6]. Detecting these rearrangements is often required for the diagnosis of ES and accepted as a desirable diagnostic criterion [6]. In our case, we have confirmed EWSR1/FLI fusion in both 1st and 2nd biopsy materials.
Human placental trophoblast progenitor cells (hTPCs) promote angiogenesis and neurogenesis after focal cerebral ischemia in rats
Published in International Journal of Neuroscience, 2022
Muge Molbay, Eylem Özaydın-Goksu, Dijle Kipmen-Korgun, Ali Unal, Murat Ozekinci, Erhan Cebeci, Emin Maltepe, Emin Turkay Korgun
Western Blot analysis was performed to detect quantities of neurogenic markers in brain tissues before and after hTPC transplantation. According to these results, on the 10th day of transplantation of hTPCs, there was a statistically significant increase in the amounts of DLX5 protein (Figure 6(B)) that plays role in neuronal differentiation, migration and major angiogenic factor VEGF expression (Figure 6(J)) (p < .05). Moreover, a statistically significant increase in the amount of NKX2.2 expression was noted, which is an important transcription factor of oligodendrocyte genesis on Days 3 and 11 after transplantation of hTPC was detected (Figure 6(F)). In addition, not statistically significant, a trend toward increased expression of LHX6, Olig1, PDGFRα, VEGFR1 and VEGFR2 was also noted in animals treated with hTPC transplantation (Figure 6(C,G,I,K,L)) .
Myoepithelioma of bone: ultrastructural, immunohistochemical and molecular study of three cases
Published in Ultrastructural Pathology, 2019
Paweł Kurzawa, Martin K. Selig, Patryk Kraiński, Michał Dopierała, G. Petur Nielsen
The myoepithelial cells themselves contain intermediate filaments: vimentin, the contractile filaments actin, and myosin, as well as tropomyosin and S100 protein.38,39 Immunohistochemically, myoepithelial tumors stain positively for S100 protein, vimentin, calponin, and GFAP along with positive reaction for different epithelial markers like keratins, EMA.2,10–12 Muscle-specific actin and myofilaments are expressed only in a proportion of cases of benign and malignant myoepitheliomas.2,13 Hence, the absence or presence of these markers does not exclude a diagnosis of myoepithelial tumors. Recent studies revealed a widespread SOX10 positivity in cutaneous myoepitheliomas, with negative reaction for MiTF.12 A small subset of myoepithelial tumors shows NKX2-2 expression.40