Explants-isolated human placenta and umbilical cord cells share characteristics of both epithelial and mesenchymal stem cells

Vol. 57 No. 2 Suppl., 2016
This supplement was not sponsored by Outside Organizations.

ROMANIAN JOURNAL of MORPHOLOGY and EMBRYOLOGY

Diana Maria Anastasiu, Ada Cean, Maria Florina Bojin, Adrian Gluhovschi, Carmen Panaitescu, Virgil Paunescu, Gabriela Tanasie

In recent years, identification of new sources of adult stem cells developed rapidly, pursuing to find easily available tissues, which will give rise to homogenous stem cells populations. Up to present, bone marrow-derived mesenchymal stem cells (BM-MSCs) are unanimously considered to fulfill the criteria for being used in clinical settings, but adipose stem cells, placental and umbilical cord stem cells, and other tissue-derived stem cells are making their way to being used at least in autologous transplantation. We isolated cellular populations from placental tissue and umbilical cord using the explants method. The placental (PL) and umbilical cord (UC)-derived cells were cultured and expanded in appropriate conditions for generation of stem cells. We assessed the stemness characteristics of the tissue-isolated cells and compared them to an established MSCs line. For this purpose, we determined the immunophenotype, morphological and ultrastructural characteristics, as well as functional abilities of PL- and UC-derived cells. Flow cytometric evaluation of cells revealed presence of CD90, CD73, and CD105 stem cells markers, while the cells were negative for CD34, CD45 and HLA-DR. Immunocytochemical staining showed that 100% of PL- and UC-derived cells are positive for vimentin and CD105 expression, while cytokeratin was revealed in less than 10% in both tissue-isolated cells. Morphological and ultrastructural characteristics of cells exposed analogous cellular size and intracellular organization, similar to MSCs, but detailed view of UC-derived cells by transmission electron microscopy (TEM) demonstrated presence of intercellular junctions-desmosomes, similar to epithelial cells. Both PL- and UC-derived cells confirmed their trilineage potential, being able to differentiate into adipocytes, osteoblasts, and chondrocytes in different proportions. Flow chamber in vitro assay was used to determine to what extent PL- and UC-derived cells are able to adhere to substrates (VCAM and ICAM) and we showed progressively decreased adhesion of both cellular types, inversely proportional to the generated shear stress. We may conclude that explants-isolated placental and umbilical cord cells are endowed with characteristics of both epithelial and mesenchymal stem cells, and purification procedures are additionally required for safe use of these cells in diverse clinical applications.

Corresponding author: Ada Cean, Biotech Engineer, PhD; e-mail: teleaada@gmail.com

Download PDF

ROMANIAN JOURNAL of MORPHOLOGY and EMBRYOLOGY

Nora Lupsan, Liliana Resiga, Adina Bianca Bosca, Carmen Georgiu, Doinita Crisan, Claudiu Mirescu, Anne-Marie Constantin, Ioan Simon, Alina Simona Sovrea

A rare neuroendocrine tumor, the pheochromocytoma (PCC) raises problems due both the limited experience of the researchers in this field and its pathogenic mechanisms, still not fully elucidated. The malignant potential of this tumor cannot be predicted based on its macro- or microscopic aspects, but on the presence of metastases. The aims of this study were: (1) the reevaluation of data for a pertinent and complete tumor diagnostic and prognostic pattern; (2) the statistical correlation of all investigated parameters with the malignant form and the survival rate in order to obtain a possible predictor of malignancy; (3) the potential identification of initially diagnosed benign tumors that become malignant in time. The retrospective study was conducted on 17 patients diagnosed with pheochromocytoma. We investigated: the personal data, the associated neuroendocrine syndromes, the clinical, the laboratory, the macro- and microscopic data [location, size, Hematoxylin-Eosin (HE) pheochromocytoma of the adrenal gland scaled score (PASS score), and immunohistochemical aspects] and the survival rate (analyzed by Kaplan-Meier method and Log-Rank test). The influence of diagnostic parameters on malignancy was calculated taking into consideration the survival rate. By reevaluation of the 17 cases, we tried to emphasize the value of a complex diagnosis pattern for PCCs, based on the correlation between clinical data, laboratory findings and microscopic features. A significant statistical difference between benign and malignant forms was not registered, but there were parameters as age, association with neuroendocrine syndromes, PASS score and specifically Ki-67 mitotic index that had a powerful impact on the survival rate and could be consider as possible predictors of malignancy. The potential of PCC malignant transformation was revealed in our study, by two cases that have metastasized in time.

Corresponding author: Alina Simona Sovrea, Associate Professor, MD, PhD; e-mail: a_sovrea@yahoo.com

Download PDF