On Monday, June 2, SIVB’s In Vitro Animal Cell Sciences Section (IVACS) held a Student and Post-Doctoral Oral Presentation Competition. Many abstracts have been submitted to this competition and the top contestants were chosen to present their research work based on the quality of their abstracts and accomplishments. All the presentations were highly professional and the level of the presented research work was impressive. Each of the participants received many questions from both the audience and the judges. The panel of judges including Dr. Michael J. Fay, Dr. Brad L. Upham, Dr. John Harbell, Dr. Barbara Doonan, Dr. Magnolia Ariza-Nieto, Dr. Cynthia L. Goodman, Dr. Lia H. Campbell, Ms. Kathryn M. Houk and Dr. Addy Alt-Holland deliberated for quite a while at the end of the competition. We chose Michael Goblirsch from University of Minnesota as the 1st place winner, Jana Koo from St. John’s University as the 2nd place winner and Chunyan Wu from Cornel University as the 3rd place winner. Certificates and cash awards were presented to these students at the IVACS Business Meeting. We highly encourage all qualified students and Post-Doctoral candidates to submit their abstracts to the 2015 competition.
Addy Alt-Holland, IVACS Chair
First Place
Development and Characterization of a Honey Bee (Apis mellifera) Cell Line
The relationship that humans have with honey bees is multi-facetted. For example, growers and beekeepers realize economic gains through pollination services that honey bees provide to over 100 commercial crops. Honey bees are the subject of broad studies in development, aging, and the evolution of complex traits such as social behavior. Moreover, beekeeping for leisure has increased in popularity, especially in urban settings where minimal space is needed to set one or two hives. Unfortunately, the future of our longstanding relationship with honey bees is uncertain. Annual levels of colony death are well-above normal attrition, and there remains to be identified a definitive cause(s) to explain these atypical losses. Hindering investigation into widespread colony death is the lack of in vitro systems derived from honey bee cells to provide a controlled, homogenous environment for the input of factors suspected to have a negative impact on bee health. Here, we report the establishment of the first continuous honey bee cell line, which we have named AME-711. AME-711 was isolated from embryonic tissues, and is characterized as adherent, fibroblast-type cells according to morphology. Cells from the line are mainly diploid (2n = 32) by karyology, and sequence analysis of the mitochondrial-encoded cytochrome c oxidase subunit I gene confirms that it is of Apis mellifera origin. The population doubling time is approximately 4 days and the line is passaged every 10-14 days. The AME-711 line has remained in continuous culture for at least 2.5 years and survives cryopreservation in liquid nitrogen. As a demonstration of the utility of the line, we also show that AME-711 cells are susceptible to infection with the emerging fungal pathogen, Nosema ceranae, a contributing factor to honey bee decline. The AME-711 honey bee cell line will serve as a powerful tool for future studies in transgenesis, host-pathogen interactions, toxicology, and nutrition.
Mike Goblirsch, University of Minnesota, 219 Hodson Hall, 1980 Folwell Ave., St. Paul, MN 55108. In Vitro Cellular and Developmental Biology, 50:S26, 2014
Second Place
Regulation of RNA Polymerase III Transcription by Daidzein in MCF-7 Cells
RNA polymerase III (RNA pol III) synthesizes small untranslated RNAs involved in metabolic processes such as translation (tRNA, 5SrRNA) and mRNA splicing (U6 snRNA). Also, deregulation of RNA pol III activity has been directly linked to cancer cell transformation. In particular a subunit of TFIIIB, termed Brf2 required for a proper initiation by RNA pol III, behaves as an oncogene in certain lung cancers. Polyphenols, including EGCG and daidzein have been shown to possess a number of chemopreventive properties. Our lab has previously demonstrated that EGCG negatively regulates RNA pol III transcription in cancer cells via the TFIIIB subunit Brf2. We hypothesized that daidzein also regulates RNA pol III transcription. MCF-7 cells were treated with increasing concentrations of daizein (0, 1, 3 and 10 mM) and analyzed for its effect on RNA pol III transcription. Low daidzein concentrations decrease the activity on the RNA pol III promoters U6 and tMet. Interestingly, treatment of MCF-7 cells with a 10 mM dose of daidzein leads to an increase in the U6 and tRNA transcription. Additionally, daidzein treatment alters Brf1 and Brf2 expression levels in a dose dependent manner. This data suggests that Brf2 and Brf1 could be the targets for regulation of RNA pol III transcription by daidzein. Subsequently, we investigated possible mechanisms by which daidzein regulates the expression of the Brf2 and Brf1. Using methylation sensitive restriction enzymes, we demonstrate that daidzein alters the Brf2 promoter methylation profile. Our data indicate that daidzein regulates RNA pol III transcription by regulating the expression of TFIIIB subunits. Mechanistically, changes in Brf2 expression levels may involve epigenetic regulation of the Brf2 promoter.
Jana Koo, St. John’s University, 7150 260th Street, 2nd Floor, 7150 260th Street, Glen Oaks, NY 11004. In Vitro Cellular and Developmental Biology, 50:S26, 2014
Third Place
Profiles of Secretory Mature hsa-miR-22-3p and DNMT1 Transcript Abundance During Hepatogenic Differentiation of Mesenchymal Stem Cells (MSCs)
Background Studies have shown a direct relationship between obesity and the incidence of cancer,and the dysregulation of adipokines is a common abnormality in both conditions. Adiponectin is an antiangiogenic, antiatherogenic, anti-inflammatory, insulin sensitizing and anticancer biomarker (Barb D, et al 2006). Irisin is a newly discovered peptide hormone, mainly expressed in response to exercised and physical activity. MicroRNAs are non-coding important regulatory molecules that target specific mRNAs. Adiponectin, irisin and microRNAs are secretory biomarkers useful both in vivo and in vitro. The goal is to develop a human in vitro model using differentiated mesenchymal stem cells (MSCs) to study regulatory signaling. Methods This in vitro work is complemented with a clinical prospective observational study (IRB number 1207-27). Donors (ongoing n=38 and n=24 controls) undergoing weight lost surgery sign consent prior joining the study. Total adiponectin, irisin and secretory microRNAs are assayed on fasting plasma, collected at baseline and 12 weeks post-op. Bone marrow, omental adipose tissue and mononuclear cells in circulation are used for the isolation, expansion and differentiation of MSCs. Hepatogenic differentiation is achieved following the protocol by Stock P et al 2010. Time course demethylation with 5’- azacytidine is monitored with qPCR for DNMT1, adiponectin and FNDC5. Additionally profiles of adiponectin, irisin and hsa-miR-22 3p, are done on media. Results Our observations suggest that MSCs isolated from bone marrow, omental adipose tissue or mononuclear cells are consistent. Hypoadiponectinemia, insulin sensitivity and T2D are resolved 12 weeks post-op; however, the profiles of mature secretory microRNAs as well as the levels of irisin and the qPCR transcript abundance are donor dependent as well as the microRNA profiles assayed on the isolated MSCs. Conclusion These results suggest the interactions between hsa-miR-22-3p and DNMT1 could hold clues in understanding adipokine dysregulation and the outcome of weight lost interventions.
Chunyan Wu, Cornell University, 526 Campus Road, 305 Weill Hall, Cornell University, Ithaca, NY 14850. In Vitro Cellular and Developmental Biology, 50:S27, 2014
