Project description:After thawing, the mechanism of apoptosis advancing in human ES cells was invesitigated mainly by Gene conpath analysis. As time passed after thawing, nuclear fragmented cells increased more and more in cR-/mR- and cR+/mR-, but in cR+/mR+ and cR-/mR+, thawed cells formed cluster markedly, which was seen among three cell lines. Flow cytometry using TUNEL assay supported final colony formation ratio, which defined that such cell death was due to apoptosis. Gene map analysis 12 hours later after thawing of cR-/mR- showed activation of IL-1? & its receptor IL-1R and TGF-? & its receptor ACVR1C required for activation of caspase-8, initiation of caspase-8 and 10 and marked activation of ARHGDIB promoting actin reorganization comparing to cR+/mR+. Recovered cell lines in any condition did not lose proliferation and pluripotency regardless of ROCK inhibitor treatment.?These results showed apoptotic events after thawing were more marked in cR- and advanced through autoenhanced cascaded mechanism followed by initiation of self-cytokain activity, and were suppressed by ROCK inhibitor Y-27632. To investigate the protective mechanism caused by a novel cryo-technique of human embryonic stem (hES) cells using ROCK inhibitor Y-27632 against the cell death due to cryopreservation and thawing with Gene map analysis in addition to estimations of survival rate, apoptosis, undifferentiated states and pluripotency, the dissociated hES cells were cryopreserved in a freezing container in the following four conditions: addition of 10µM of Y-27632 to 1: cryoprotection solution and post-thawing medium (cR+/mR+), 2: only addition to cryoprotection (cR+/mR-), 3: only addition to post-thawing medium (cR-/mR+), 4: no addition to any medium (cR-/mR-).
Project description:Some biosamples obtained from biobanks may go through thawing before processing. We aim to evaluate the effects of thawing at room temperature for different time periods on gene expression analysis.
Project description:In this study, we assess technical differences between commonly used single-cell RNA-Sequencing (scRNA-Seq) methods. We perform scRNA-seq on a homogenous population of mouse embryonic stem cells along with two kinds of control spike-in molecules to assess sensitivity and accuracy of these specific methods. In this dataset, we assess the RNA-degradation and decay rates by subjecting both spike-in molecules to range of repeated freezing and thawing (freeze-thaw) cycles. We manually add spike-in molecules across a 96-well plate (containing cells and reagents), perform Smart-Seq2 method manually and generate single-cell libraries using Nextera XT kit
Project description:After thawing, the mechanism of apoptosis advancing in human ES cells was invesitigated mainly by Gene conpath analysis. As time passed after thawing, nuclear fragmented cells increased more and more in cR-/mR- and cR+/mR-, but in cR+/mR+ and cR-/mR+, thawed cells formed cluster markedly, which was seen among three cell lines. Flow cytometry using TUNEL assay supported final colony formation ratio, which defined that such cell death was due to apoptosis. Gene map analysis 12 hours later after thawing of cR-/mR- showed activation of IL-1β & its receptor IL-1R and TGF-β & its receptor ACVR1C required for activation of caspase-8, initiation of caspase-8 and 10 and marked activation of ARHGDIB promoting actin reorganization comparing to cR+/mR+. Recovered cell lines in any condition did not lose proliferation and pluripotency regardless of ROCK inhibitor treatment. These results showed apoptotic events after thawing were more marked in cR- and advanced through autoenhanced cascaded mechanism followed by initiation of self-cytokain activity, and were suppressed by ROCK inhibitor Y-27632.
Project description:Human breast milk (HBM) is the ideal source of nutrients for infants and is rich in microRNA (miRNA). In recent years, expressed breast milk feeding rather than direct breastfeeding is becoming increasingly prevalent for various reasons. HBM requires storage and processing, which can cause various changes in the ingredients. We investigated how the miRNAs in HBM change due to processes often used in real life. HBM samples collected from 10 participants were each divided into 7 groups according to the storage temperature, thawing method, and storage period. And we analyzed the miRNA changes in each group. Significant changes in expression of several miRNAs were confirmed when HBM were heated by microwave immediately after collection, stored at room temperature for 1 week, or frozen for 1 week. Changes in expression were also dependent on the frozen period or thawing method. However, there was no change in the miRNA expression in all samples refrigerated for 1 week. The expression of miRNA can change depending on the diverse processing, storage, and thawing methods of breast milk, and refrigerated storage may be an ideal method to maintain a state of miRNA.
Project description:Human primary granulosa cells (GCs) derived from women, undergoing oocyte retrieval, can be cultured and are a cellular model for the study of human ovarian functions. In vitro they change rapidly, resembling initially cells of the preovulatory follicle and then cells of the corpus luteum. They are derived from individual patients and their different medical history, lifestyle and age lead to heterogeneity. Thus, cells can rarely be ideally matched for cellular experiments or, if available, only in small quantities. We reasoned that cryopreservation of human GCs may be helpful. Previous studies indicated feasibility of such an approach, but low survival of GCs was reported and consequences on GC functionality were only partially evaluated. We tested a slow freezing protocol (employing FCS and DMSO) of GCs upon isolation from follicular fluid. We compared cryopreserved and subsequently thawed cells with fresh, not cryopreserved ones, from the same patients. About 80 % of human GCs survived freezing/thawing. Neither morphology, nor levels of cell-cell contact, mitochondrial and steroidogenic genes were different between the two groups in cells cultured for 1-5 days. A proteomic analysis revealed no statistical significance in the abundance of a total of 5962 proteins. Both groups produced comparable basal levels of progesterone and responded similarly to hCG with elevation of progesterone. Taken together, we describe a rapid and readily available method for the cryopreservation of human GCs. We anticipate that it will allow future large-scale experiments and may thereby improve cellular studies with human ovarian cells.