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Several investigations are being done to increase the short lifetime of mesenchymal stem cells (MSCs). One of the crucial genes involved in the immortalization of MSCs, hTERT (human telomerase reverse transcriptase), is activated in most publications using viral-based techniques. In this work, we investigated the use of platelet-derived (PMPs) and B cell precursor leukemia-derived microparticles as a nonviral method to trigger and compare the expression of the hTERT gene in MSCs. MSCs were extracted from the umbilical cord for the current investigation and identified using a flow cytometry approach and an inverted microscope. The Nalm-6 cell line and platelet concentrate were used to isolate microparticles (MPs). MSCs and MPs were cocultured for 14 days at 25-, 50-, and 100 μg/ml concentrations. qRT-PCR was used to research the expression of the hTERT gene. SPSS 26.0's t test was used to compare the outcomes. After coculture with platelet MPs, MSCs had higher levels of hTERT gene expression than the control group. In contrast, this gene's expression was concurrently decreased in MSCs exposed to MPs generated from Nalm-6. We demonstrated that following 14-day treatment, PMP significantly boosted the hTERT gene expression in MSCs, while the Nalm-6 MPs lowered the gene expression. However, additional studies are necessary due to the stability of hTERT gene expression and the immortalization of MSCs following exposure., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Cell-derived microparticles (MPs) are membrane vesicles that have emerged as a potential biomarker for various diseases and their clinical complications. This study investigates the role of MPs as a risk factor for blood transfusion in patients with valve heart disease undergoing cardiac surgery., Methods: Forty adult patients undergoing heart valve surgery with cardiopulmonary bypass (CPB) were enrolled, and venous blood samples were collected prior to surgical incision. Plasma rich in MPs was prepared by double centrifugation, and the concentration of MPs was determined using the Bradford method. Flow cytometry analysis was performed to determine MPs count and phenotype. Patients were divided into "with transfusion" (n = 18) and "without transfusion" (n = 22) groups based on red blood cell (RBC) transfusion., Results: There was no significant difference in MPs concentration between the "with transfusion" and "without transfusion" groups. Although the count of preoperative platelet-derived MPs (PMPs), monocyte-derived MPs (MMPs), and red cell-derived MPs (RMPs) was higher in "without transfusion" group, these differences were not statistically significant. The preoperative PMPs count was negatively correlated with RBC transfusion (P = 0.005, r = -0.65). Multivariate logistic regression analysis revealed that the count of CD41 + PMPs, Hemoglobin (Hb), and RBC count were risk factors for RBC transfusion., Conclusion: This study suggests that the presurgical levels of PMPs, Hb, and RBC count can serve as risk factors of RBC transfusion in patients with valve heart disease undergoing cardiac surgery. The findings provide insights into the potential use of MPs as biomarkers for blood transfusion prediction in cardiac surgery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Société française de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.)

Background: Cell-derived microparticles (MPs) as membrane vesicles are procoagulant. They play a role in surgical hemostasis. In this study, the correlations between the circulating level of cell-derived MPs and surgical variables in heart valve surgery were investigated. Methods: The present prospective case-series study was conducted in Rajaie Cardiovascular Medical and Research Center from January through March 2021. Forty patients undergoing heart valve surgery with cardiopulmonary bypass (CPB) were enrolled. Before the induction of anesthesia and 30 minutes after the administration of protamine sulfate, venous blood samples were collected. After MP isolation, the concentration of MPs was determined via the Bradford method. Flow cytometry analysis was performed to determine the MP count and phenotype. Intraoperative variables and postoperative routine coagulation tests were defined as surgical variables. Postoperative coagulopathy was defined as an activated partial thromboplastin time (aPTT) ≥48 seconds or an international normalized ratio (INR) >1.5. Results: The total concentration of MPs and the MP count increased significantly after surgery compared with before surgery. The postoperative concentration of MPs was positively correlated with the CPB time (P=0.030, ρ=0.40). The preoperative concentration of MPs was significantly lower in patients with higher postoperative aPTT and INR (P=0.003, P= -0.50 and P=0.020, P= -0.40, respectively). In multivariate logistic regression analysis, the preoperative MP concentration (OR, 1.00; 95% CI, 1.00 to 1.01; P=0.017) was considered a risk factor for postoperative coagulopathy. Conclusion: The levels of MPs, especially platelet-derived MPs, rose after surgery, in correlation with the CPB time. Given the role of MPs in the induction of coagulation and inflammation, they can be considered therapeutic goals for preventing postoperative complications. In addition, the preoperative levels of MPs are a risk factor for predicting the occurrence of postoperative coagulopathy in heart valve surgery. [ABSTRACT FROM AUTHOR]

Background: Microparticles (MPs) are small vesicles released from the cell membrane. Accordingly, these contain active molecules to mediate biological processes, including cell proliferation and cell cycle progression. The fusion of myeloma cell lines with immunized B lymphocytes is a critical step of hybridoma technology. MPs modulate lymphoproliferation, thereby facilitating B cell expansion and successful immortalization. Human alloimmune B cells are considered valuable sources of monoclonal antibodies, and peripheral blood is a pool of B lymphocytes. The present study aimed to investigate the role of myeloma-derived MPs in the proliferation of alloimmune peripheral blood mononuclear cells (PBMCs). Materilas and Methods: In the current experimental study, ultracentrifugation isolated MPs from three different myeloma cell lines, including U266, P3x63Ag8, and SP2/0. PBMCs were extracted from the whole blood of a patient with thalassemia alloimmune exposed to MPs. Thereafter, both the proliferation and cell viability were evaluated using inverted microscopy and the trypan blue staining method. Results: MPs derived from the P3X63Ag8 myeloma cell line were shown to have the most effects on cell proliferation and viability (p=0.0005). MPs of the SP2/0 cell line initially increased the proliferation of PBMCs, but viable cells were drastically reduced in the following weeks. As well, U266 cell-derived MPs increased the proliferation of PBMCs (p=0.0001), but it was half of the group receiving P3x63Ag8 derived MPs. However, the viability of treated cells remained almost constant for 5-weeks. Conclusion: Altogether, the obtained data indicated that P3X63Ag8 and U266 derived MPs could increase the viability of PBMCs. If the complimentary examination is confirmed, these MPs could also be used as the potential agents in B lymphocyte proliferation, thereby helping in immortalization and antibody production. [ABSTRACT FROM AUTHOR]