Ex vivo immunological evaluation of stable mixed chimeric patients after matched related donor allogeneic transplantation in sickle cell disease

Background aimsAllogeneic hematopoietic stem cell transplantation is curative for sickle cell disease, and the use of matched related donors, non-myeloablative conditioning and sirolimus immunosuppression results in stable mixed chimerism without graft-versus-host disease (GVHD). However, the time to terminate sirolimus while maintaining mixed chimerism is unclear.MethodsIn this study, we developed a two-way mixed lymphocyte reaction (MLR) to evaluate ex vivo immunoreaction in mixed chimeric patients.ResultsIn co-culture of peripheral blood mononuclear cells (PBMCs) from two healthy controls (without irradiation), we detected proliferation at various ratios of PBMC mixtures (1:9 to 9:1) as well as various concentrations of sirolimus, suggesting that two-way MLR is applicable to patients (having >10% chimerism) undergoing sirolimus treatment. In two-way MLR using PBMCs (including donor and recipient cells) from mixed chimeric patients (n = 28), greater ex vivo proliferation was observed <6 months compared with >6 months post-transplant and healthy control PBMC monoculture. Robust ex vivo proliferation was observed in a patient with acute GVHD, and persistent ex vivo proliferation (until 2 years) was observed in a patient with decreasing donor chimerism.ConclusionsIn summary, we demonstrated that in two-way MLR, ex vivo immunoreaction decreases to low levels ~6 months post-transplant. These findings suggest a rationale to continue immunosuppression for 6 months.     

Condensin-Dependent Chromatin Compaction Represses Transcription Globally during Quiescence

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Molecular mechanism of therapeutic approaches for human gastric cancer stem cells

Gastric cancer(GC)is a primary cause of cancer-related mortality worldwide,and even after therapeutic gastrectomy,survival rates remain poor.The presence of gastric cancer stem cells(GCSCs)is thought to be the major reason for resistance to anticancer treatment(chemotherapy or radiotherapy),and for the development of tumor recurrence,epithelial–mesenchymal transition,and metastases.Additionally,GCSCs have the capacity for self-renewal,differentiation,and tumor initiation.They also synthesize antiapoptotic factors,demonstrate higher performance of drug efflux pumps,and display cell plasticity abilities.Moreover,the tumor microenvironment(TME;tumor niche)that surrounds GCSCs contains secreted growth factors and supports angiogenesis and is thus responsible for the maintenance of the growing tumor.However,the genesis of GCSCs is unclear and exploration of the source of GCSCs is essential.In this review,we provide up-todate information about GCSC-surface/intracellular markers and GCSC-mediated pathways and their role in tumor development.This information will support improved diagnosis,novel therapeutic approaches,and better prognosis using GCSC-targeting agents as a potentially effective treatment choice following surgical resection or in combination with chemotherapy and radiotherapy.To date,most anti-GCSC blockers when used alone have been reported as unsatisfactory anticancer agents.However,when used in combination with adjuvant therapy,treatment can improve.By providing insights into the molecular mechanisms of GCSCs associated with tumors in GC,the aim is to optimize anti-GCSCs molecular approaches for GC therapy in combination with chemotherapy,radiotherapy,or other adjuvant treatment.     

The effects of immersive garden experience on the health care to elderly residents with mild-to-moderate cognitive impairment living in nursing homes after the COVID-19 pandemic

Elderly patients living in long-term care facilities have been restricted from leaving to comply with social distancing guidelines during the COVID-19 pandemic. This has led to a worsening of disorders, such as anxiety and depression. This study aims to understand the health benefits of an immersive garden experience to elderly nursing home residents with mild-to-moderate cognitive impairments. Virtual reality devices were used to provide immersive garden experiences for the residents who were unable to go outside. The heart rate and heart rate variability (HRV) data of the participants of the participants were collected using biofeedback instruments, and changes in the low frequency/high frequency (LF/HF) and the standard deviation of the NN interval (SDNN) values caused by immersive garden experiences were discussed. The results show that the immersive garden experiences were beneficial to these elderly residents. Within 6 min of completing the experiment, we found that the heart rates of participants had dropped slightly, while SDNN and HF values continued to rise. SDNN values before and after the experiment demonstrated a statistically significant improvement. Furthermore, participants expressed their satisfaction with the video intervention program. The results indicated that nursing homes can provide immersive landscape experiences to help increase HRV and SDNN of their elderly residents. This will not only help these residents recall beautiful memories of their past, but will also improve their quality of life.

     

Development and validation of a liquid chromatography-tandem mass spectrometry for the determination of BPR0L075, a novel antimicrotuble agent, in rat plasma: application to a pharmacokinetic study

A rapid and sensitive liquid chromatography-tandem mass spectrometric method (LC-MS/MS) had been developed and validated to determine the concentrations of BPR0L075 in rat plasma. After a simple protein precipitation of plasma samples by acetonitrile, BPR0L075 was analyzed on a C(8) column at a flow rate of 0.5 mL/min. The mobile phase consisted of a mixture of 10 mM ammonium acetate containing 0.1% formic acid and acetonitrile (20:80, v/v). Both BPR0L075 (analyte) and the internal standard (BPR0L092) were determined using electro-spray ionization and the MS data acquisition was via multiple reactions monitoring (MRM) in positive scanning model. The MS/MS ion transitions monitored are m/z 342.2/195.2 and 312.5/165.2 for BPR0L075 and BPR0L092, respectively. The low limit of quantitation was 0.5 ng/mL. Each plasma sample was chromatographed within 5 min. The method was validated with respect to linearity, accuracy, precision, recovery, and stability. A good linear relationship was observed over the concentration range of 0.5-1000 ng/mL (r>0.9994). Absolute recoveries ranged from 63.45 to 68.34% in plasma at the concentrations of 2, 40, 400, and 800 ng/mL. The intra- and inter-day accuracy ranged from 92.04 to 111.80%. Intra- and inter-day relative standard deviations were 1.08-3.29% and 1.96-5.46%, respectively. This developed and validated assay method had been successfully applied to a pharmacokinetic study after intravenous injection of BPR0L075 in rats at a dose of 5mg/kg.     

Aggregation of human dental pulp cells into 3D spheroids enhances their migration ability after reseeding

Multicellular three-dimensional (3D) spheroids allow intimate cell–cell communication and cell–extracellular matrix interaction. Thus, 3D cell spheroids better mimic microenvironment in vivo than two-dimensional (2D) monolayer cultures. The purpose of this study was to evaluate the behaviors of human dental pulp cells (DPCs) cultured on chitosan and polyvinyl alcohol (PVA) membranes. The protein expression of hypoxia-inducible factor 1-α (HIF-1α) and vascular endothelial growth factor (VEGF), and the migration ability of the DPCs from 2D versus 3D environments were investigated. The results showed that both chitosan and PVA membranes support DPCs aggregation to form multicellular spheroids. In comparison to 2D cultures on tissue culture polystyrene, DPC spheroids exhibited higher protein expression of HIF-1α and VEGF. The treatment with YC-1 (inhibitor to HIF-1α) blocked the upregulation of VEGF, indicating a downstream event to HIF-1α expression. When DPC spheroids were collected and subjected to the transwell assay, the cells growing outward from 3D spheroids showed greater migration ability than those from 2D cultures. Moreover, DPCs aggregation and spheroid formation on chitosan membrane were abolished by Y-27632 (inhibitor to Rho-associated kinases), whereas the inhibitory effect did not exist on PVA membrane. This suggests that the mechanism regulating DPCs aggregation and spheroid formation on chitosan membrane is involved with the Rho-associated kinase signaling pathway. In summary, the multicellular spheroid structure was beneficial to the protein expression of HIF-1α and VEGF in DPCs and enhanced the migration ability of the cells climbing from spheroids. This study showed a new perspective in exploring novel strategies for DPC-based research and application.