Tumorigenic and tumoricidal properties of exosomes in cancers; a forward look.

In recent decades, emerging data have highlighted the critical role of extracellular vesicles (EVs), especially (exosomes) Exos, in the progression and development of several cancer types. These nano-sized vesicles are released by different cell lineages within the cancer niche and maintain a suitable platform for the interchange of various signaling molecules in a paracrine manner. Based on several studies, Exos can transfer oncogenic factors to other cells, and alter the activity of immune cells, and tumor microenvironment, leading to the expansion of tumor cells and metastasis to the remote sites. It has been indicated that the cell-to-cell crosstalk is so complicated and a wide array of factors are involved in this process. How and by which mechanisms Exos can regulate the behavior of tumor cells and non-cancer cells is at the center of debate. Here, we scrutinize the molecular mechanisms involved in the oncogenic behavior of Exos released by different cell lineages of tumor parenchyma. Besides, tumoricidal properties of Exos from various stem cell (SC) types are discussed in detail.

Leukocyte Reduction Filters Are Reliable and Economic Source for Natural Killer Cell Preparation.

Background: An issue that hinders researchers' access to Natural Killer (NK) cells is their low proportion in peripheral blood leukocytes. This issue is currently addressed by methods involving a series of differentiation and expansions that are time-consuming and expensive. Objective: We have investigated whether the used leukocyte reduction filters, a by-product in the blood transfusion practice that currently is considered waste, can be utilized as a source of the NK cells. Methods: Following the blood donation of 46 donors based on the Iranian Blood Transfusion Organization's protocols, a sample of peripheral blood of each donor and the leukocyte reduction filter used in their donation procedure have been obtained. The entrapped cells were flushed back from the leukocyte reduction filters. Both groups of samples were analyzed using an automatic hematological analyzer. NK cell isolation was done by the MACS negative selection method. The samples have been comparatively analyzed utilizing flow cytometry data of NK cells' subpopulation compositions, viability, degranulation patterns, and cytotoxic capacity against the K562 cell line. Results: Every major leukocyte population was abundant in the samples extracted from the used leukocyte reduction filters. The NK cells extracted from leukocyte reduction filters did not show any statistically meaningful differences (P<0.5) from peripheral blood samples in terms of subpopulation composition, viability, degranulation potency, and cytotoxic capacity. Conclusion: Used leukocyte reduction filters can be considered an economic, easy to obtain, and robust source of abundant research-grade NK cells.

Investigation of the potential of leukoreduction filters in the creation of anti-inflammatory compound.

BACKGROUND: Some viruses such as SARS, SARS-CoV-2, and MERS cause an imbalance in immune responses and leads to an acute inflammatory reaction named cytokine storm. In this situation, an anti-inflammatory component can modulate the immune system and decrease mortality. The aim of this study was investigate the potential of leukoreduction filters (LRFs) in creating an anti-inflammatory compound. MATERIALS AND METHODS: In this experimental study, firstly optimal dose of the anti-inflammatory drug was obtained through LRFs treatment with 0.1 mg, 0.4 mg, 0.6 mg of Betamethasone. Then inflammatory and anti-inflammatory cytokine in gene and protein level was evaluated. In the next step, LRFs were categorized into treatment 1, treatment 2, control assay, and control groups and treated with the optimal dose of the drug. Finally, the obtained compound was investigated for the concentration of IL1, IL6, and TNF-α as inflammatory and IL4, IL1Ra, and IL10 as anti-inflammatory cytokines. RESULTS: The results of the current study showed that the concentration of 0.4 mg of Betamethasone lead to a significant increase of anti-inflammatory cytokine in gene and protein levels. The results also showed that the Betamethasone treated groups (treatment1) causes a significant increase in the secretion of anti-inflammatory cytokine compares to the control while inflammatory cytokine remained at the control level. CONCLUSION: The results showed that under influence of anti-inflammatory drug treatments the production and secretion of anti-inflammatory cytokines can be induced in LRFs.

Long-term Effects of Regular Whole Blood Donation on Peripheral Blood CD34+ Cells Population with using Leukoreduction Filters.

Background & Objective: Trapped cell population in leukoreduction filters (LRFs) contains such a significant number of CD34+ hematopoietic stem cells that can be recovered to be used in research studies. Methods: Samples (n=20) were obtained from 10 first-time donors and 10 regular blood donors with more than 30 times blood donation. After separating leukocytes from LRFs by backflushing, total leukocyte number and differential count were determined in both groups using an automated haemocytometer. Then cell viability and CD34+ cell quantification were assessed using 7- amino-actinomycin D and fluorescent-labeled monoclonal antibodies using flow cytometry, respectively. Results: Total leukocyte count was 665±164.92×106 in the first-time blood donors and 883±233.89×106 in the regular donors, which were not significantly different (P=0.08). While the number of CD34+ cells was significantly reduced in the regular donors compared to the first-time donors (0.58±0.20×106/µL vs. 0.36±0.22×106/µL; P=0.034). There was no significant difference in terms of absolute neutrophil count (10.58±3.66×06 vs. 13.17±6.45×106/µL; P=0.349), lymphocytes (7.75±3.11×106 vs. 10.38±3.77×106 /µL; P=0.917), and monocytes (2.31±0.88×106 vs. 2.59±1.09×106/µL; P=0.591) between the first-time and regular donor groups, respectively. Based on the correlation coefficients, the participants' age had no significant effect on these variables. Conclusion: The results of this study depicted that regular blood donation reduces the number of CD34+ cells in the peripheral blood (PB) of regular donors while it has no significant effect on the ratio of myeloid to lymphoid cells of the two groups.

Leukocyte reduction filters as an alternative source of peripheral blood leukocytes for research

ABSTRACT Introduction: Peripheral blood leukocytes are a suitable cell model for science research. However, blood samples from healthy volunteers are limited in volume and difficult to obtain due to the complexity of volunteer recruitment. Objective: Therefore, it is urgent to find an alternative source of peripheral blood leukocytes. Method: One of the possibilities is the use of leukocyte reduction filters (LRFs) in blood banks that is used for preparation of leukoreduced blood products. More than 90% of the leukocytes are trapped in the leukofilters allowing the desired blood product to pass through. Results: It has been reported that the biological function of leukocytes collected from the filters are no different from those isolated from buffy coats, leukapheresis products and whole blood (WB) cells. Moreover, LRFs are waste products that are discarded after leukoreduction. Conclusion: Thus, leukofilters represent an economic source of human cell populations that can be used for a variety of investigative purposes, with no cost. In the present study, we reviewed the different usage of LRFs in the research, clinical and commercial applications.

Leukocyte reduction filters as an alternative source of peripheral blood leukocytes for research.

INTRODUCTION: Peripheral blood leukocytes are a suitable cell model for science research. However, blood samples from healthy volunteers are limited in volume and difficult to obtain due to the complexity of volunteer recruitment. OBJECTIVE: Therefore, it is urgent to find an alternative source of peripheral blood leukocytes. METHOD: One of the possibilities is the use of leukocyte reduction filters (LRFs) in blood banks that is used for preparation of leukoreduced blood products. More than 90% of the leukocytes are trapped in the leukofilters allowing the desired blood product to pass through. RESULTS: It has been reported that the biological function of leukocytes collected from the filters are no different from those isolated from buffy coats, leukapheresis products and whole blood (WB) cells. Moreover, LRFs are waste products that are discarded after leukoreduction. CONCLUSION: Thus, leukofilters represent an economic source of human cell populations that can be used for a variety of investigative purposes, with no cost. In the present study, we reviewed the different usage of LRFs in the research, clinical and commercial applications.

HEK293 Cells Overexpressing Nuclear Factor E2-Related Factor-2 Improve Expression of Recombinant Coagulation Factor VII.

The mammalian expression system plays a key central role in the production of therapeutic recombinant proteins. Conspicuously, any improvements in the expression system which lead to a higher expression level would have an impact especially in bio-pharmaceutical industries. In the current study, to take steps toward the improvement of expression of recombinant protein, first, we established a stable HEK293 cell line to overexpress a well-known cytoprotective and antioxidant gene, Nrf2. Next, we transiently expressed human recombinant coagulation factor VII, as an example of human recombinant protein, in the engineered-HEK293 cell line. Our results revealed that the established cells had a higher growth rate and were able to endure to UV-induced oxidative stress. Furthermore, within our expectation, our results revealed that the expression level of recombinant FVII in Nrf2-engineered HEK293 cells (315 ng/ml) was higher than the HEK293 (198 ng/ml) cells and it was functional in a coagulation test assay. Moreover, our new cell line could be a suitable cell to express other recombinant proteins especially for large-scale production of recombinant protein under other culture condition such as lower serum and suspension culture that imposed advantages especially in terms of cost benefits in bio-pharmaceutical industries.

Mesenchymal Stem Cells on Horizon: A New Arsenal of Therapeutic Agents.

Over 10 years, mesenchymal stem cells (MSCs) have been considered as valuable and suitable cells for cell-based therapy applications, particularly in clinical trials. In any case, they are as yet not utilized routinely in clinics. At first, it was believed that MSCs play their roles, especially in regenerative medicine due to their differentiation and cell replacement properties. Interestingly, it is well-known that MSCs mainly exert their therapeutic effects through their vast bioactive factors. These findings turned scientists' consideration toward cell-free therapy concepts. From this point of view, MSCs can be considered as an arsenal of natural bioreactors in variety of therapeutic agents. MSCs inherently express various important therapeutic agents such as growth factors and cytokines that can be manufactured, handled and stored as a prepared-to-go biologic product. In this review, we provide a vision, highlight as well as discuss in order to introduce competitive natural robust bioreactor MSCs on the horizon.

Lipocalin 2 enhances mesenchymal stem cell-based cell therapy in acute kidney injury rat model.

Acute kidney injury (AKI) is one of the most common health-threatening diseases in the world. There is still no effective medical treatment for AKI. Recently, Mesenchymal stem cell (MSC)-based therapy has been proposed for treatment of AKI. However, the microenvironment of damaged kidney tissue is not favorable for survival of MSCs which would be used for therapeutic intervention. In this study, we genetically manipulated MSCs to up-regulate lipocalin-2 (Lcn2) and investigated whether the engineered MSCs (MSC-Lcn2) could improve cisplatin-induced AKI in a rat model. Our results revealed that up-regulation of Lcn2 in MSCs efficiently enhanced renal function. MSC Lcn2 up-regulates expression of HGF, IGF, FGF and VEGF growth factors. In addition, they reduced molecular biomarkers of kidney injury such as KIM-1 and Cystatin C, while increased the markers of proximal tubular epithelium such as AQP-1 and CK18 following cisplatin-induced AKI. Overall, here we over-expressed Lcn2, a well-known cytoprotective factor against acute ischemic renal injury, in MSCs. This not only potentiated beneficial roles of MSCs for cell therapy purposes but also suggested a new modality for treatment of AKI.