The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Melvin L Depamphilis - One of the best experts on this subject based on the ideXlab platform.
-
geminin is essential for pluripotent Cell viability during teratoma formation but not for Differentiated Cell viability during teratoma expansion
Stem Cells and Development, 2017Co-Authors: Diane C Adlerwailes, Joshua A Kramer, Melvin L DepamphilisAbstract:Pluripotent embryonic stem Cells (ESCs) are unusual in that geminin has been reported to be essential either to prevent differentiation by maintaining expression of pluripotency genes or to prevent DNA rereplication-dependent apoptosis. To distinguish between these two incompatible hypotheses, immune-compromised mice were inoculated subcutaneously with ESCs harboring conditional Gmnn alleles alone or together with a tamoxifen-dependent Cre recombinase gene. Mice were then injected with tamoxifen at various times during which the ESCs proliferated and Differentiated into a teratoma. For comparison, the same ESCs were cultured in vitro in the presence of monohydroxytamoxifen. The results revealed that geminin is a haplosufficient gene that is essential for ESC viability before they differentiate into a teratoma, but once a teratoma is established, the Differentiated Cells can continue to proliferate in the absence of Gmnn alleles, geminin protein, and pluripotent stem Cells. Thus, Differentiated Cells did not require geminin for efficient proliferation within the context of a solid tissue, although they did when teratoma Cells were cultured in vitro. These results provide proof-of-principle that preventing geminin function could prevent malignancy in tumors derived from pluripotent Cells by selectively eliminating the progenitor Cells with little harm to normal Cells.
Diane C Adlerwailes - One of the best experts on this subject based on the ideXlab platform.
-
geminin is essential for pluripotent Cell viability during teratoma formation but not for Differentiated Cell viability during teratoma expansion
Stem Cells and Development, 2017Co-Authors: Diane C Adlerwailes, Joshua A Kramer, Melvin L DepamphilisAbstract:Pluripotent embryonic stem Cells (ESCs) are unusual in that geminin has been reported to be essential either to prevent differentiation by maintaining expression of pluripotency genes or to prevent DNA rereplication-dependent apoptosis. To distinguish between these two incompatible hypotheses, immune-compromised mice were inoculated subcutaneously with ESCs harboring conditional Gmnn alleles alone or together with a tamoxifen-dependent Cre recombinase gene. Mice were then injected with tamoxifen at various times during which the ESCs proliferated and Differentiated into a teratoma. For comparison, the same ESCs were cultured in vitro in the presence of monohydroxytamoxifen. The results revealed that geminin is a haplosufficient gene that is essential for ESC viability before they differentiate into a teratoma, but once a teratoma is established, the Differentiated Cells can continue to proliferate in the absence of Gmnn alleles, geminin protein, and pluripotent stem Cells. Thus, Differentiated Cells did not require geminin for efficient proliferation within the context of a solid tissue, although they did when teratoma Cells were cultured in vitro. These results provide proof-of-principle that preventing geminin function could prevent malignancy in tumors derived from pluripotent Cells by selectively eliminating the progenitor Cells with little harm to normal Cells.
A. Vandewalle - One of the best experts on this subject based on the ideXlab platform.
-
Immortalized renal proximal and collecting duct Cell lines derived from transgenic mice harboring L-type pyruvate kinase promoters as tools for pharmacological and toxicological studies
Cell Biology and Toxicology, 2002Co-Authors: A. VandewalleAbstract:Targeted oncogenesis in transgenic mice, where an oncogene is placed under the control of the regulatory sequences of a Cell-specific gene, has been used to derive lines of Differentiated kidney epithelial Cells derived from proximal or distal tubules or from the collecting duct. These renal Cell lines were obtained from kidneys of transgenic mice harboring the large-T and little-t antigens placed under the control of regulatory sequences of the L-type pyruvate kinase gene. This review summarizes the main properties of these Differentiated Cell lines, which are useful ex vivo Cell systems for pharmacological and toxicological studies.
Omar Bagasra - One of the best experts on this subject based on the ideXlab platform.
-
infectivity of immature neurons to zika virus a link to congenital zika syndrome
EBioMedicine, 2016Co-Authors: Brandon W Hughes, Krishna C Addanki, Ahila Sriskanda, E Mclean, Omar BagasraAbstract:Abstract Background Epidemiological data strongly suggest that microcephaly cases in Brazil are associated with the ongoing epidemic of Zika virus (ZIKV). In order to further solidify the possible link, we investigated the infectivity of ZIKV using various neuroblastoma (NB) Cell lines. Methods Six unDifferentiated, two terminally Differentiated and two retinoic acid (RA) –induced, partially Differentiated Cell lines were exposed to ZIKV strain PRVABC59, which is genetically similar to the French Polynesia strain, with 97–100% genetic homology to the current ZIKV strain found in Brazil. All infections were confirmed by real-time PCR (RT-qPCR), immunofluorescence assay (IFA) probing with anti-flavivirus E antibody, and evaluation of cytopathic effects. Findings ZIKV infected all six unDifferentiated NB Cell lines. In five out of six NB Cell lines, between 90 and 70% Cells were positive by IFA whereas for one Cell line, CCL-127, ~80% of Cells were positive for ZIKV as determined by IFA but showed persistent infection. Two Differentiated Cell lines, JFEN and T-268, were highly resistant to ZIKV with Interpretation These findings strengthen the reported association between high incidences of microcephaly and ZIKV infection in newborns in Brazil. Our results suggest that the unDifferentiated neurons are highly permissive to ZIKV infection, as one would expect during the early stages of neurogenesis in fetal brains; whereas Differentiated neurons, representative of adult brain neurons, are relatively resistant to the virus, which explains the rare occurrence of neurological complications in adults infected with ZIKV. Our studies confirm the neurotropism of the ZIKV strain closely related to the current epidemic in Latin America.
Staffan Kjelleberg - One of the best experts on this subject based on the ideXlab platform.
-
Quorum Sensing-Controlled Biofilm Development in Serratia liquefaciens MG1
Journal of bacteriology, 2004Co-Authors: Maurizio Labbate, Michael Givskov, Scott A. Rice, Shu Yeong Queck, Kai Shyang Koh, Staffan KjellebergAbstract:Serratia liquefaciens MG1 contains an N-acylhomoserine lactone-mediated quorum-sensing system that is known to regulate swarming motility colonization. In this study, we describe for S. liquefaciens MG1 the development of a novel biofilm consisting of Cell aggregates and Differentiated Cell types, such as Cell chains and long filamentous Cells. Furthermore, quorum sensing is shown to be crucial for normal biofilm development and for elaborate differentiation. A mutant of S. liquefaciens MG1 that was incapable of synthesizing extraCellular signal formed a thin and nonmature biofilm lacking Cell aggregates and Differentiated Cell chains. Signal-based complementation of this mutant resulted in a biofilm with the wild-type architecture. Two quorum-sensing-regulated genes (bsmA and bsmB) involved in biofilm development were identified, and we propose that these genes are engaged in fine-tuning the formation of Cell aggregates at a specific point in biofilm development.