Optimization of human umbilical cord blood-derived mesenchymal stem cell isolation and culture methods in serum- and xeno-free conditions.

BACKGROUND: Although umbilical cord blood (UCB) is identified as a source of mesenchymal stem cells (MSCs) with various advantages, the success in cell isolation is volatile. Therefore, it is necessary to optimize methods of cord blood-derived MSC (UCB-MSC) isolation and culture. In this study, we evaluated the efficiency of UCB-MSC isolation and expansion using different commercially available serum- and xeno-free media and investigated the capacity of autologous serum and plasma as a supplement to support cell proliferation. Additionally, we defined the presence of multilineage-differentiating stress-enduring (Muse) cells in the UCB-MSC population. Functions of UCB-MSC in in vitro angiogenesis processes and anti-cancer were also verified. METHODS: Mononuclear cells were isolated using density gradient separation and cultured in four commercial media kits, as well as four surface coating solutions. UCB-MSCs were characterized and tested on tube formation assay, and co-cultured with SK-MEL cells in a transwell system. RESULTS: The results showed that only StemMACS™ MSC Expansion Media is more appropriate to isolate and culture UCB-MSCs. The cells exhibited a high cell proliferation rate, CFU forming capability, MSC surface marker expression, trilineage differentiate potential, and chromosome stability. In addition, the culture conditions with autologous serum coating and autologous plasma supplement enhanced cell growth and colony forming. This cell population contained Muse cells at rate of 0.3%. Moreover, UCB-MSCs could induce the tube formation of human umbilical vein endothelial cells and inhibit more than 50% of SK-MEL cell growth. CONCLUSIONS: UCB-MSCs could be high-yield isolated and expanded under serum- and xeno-free conditions by using the StemMACS™ MSC Expansion Media kit. Autologous serum coating and plasma supplement enhanced cell proliferation. These UCB-MSCs had effected the tube formation process and an anti-cancer impact.

Induction of Antitumor Immunity by Exosomes Isolated from Cryopreserved Cord Blood Monocyte-Derived Dendritic Cells.

(1) Background: Dendritic cell (DC) vaccination has shown outstanding achievements in cancer treatment, although it still has some adverse side effects. Vaccination with DC-derived exosomes has been thought to overcome the side effects of the parental DCs. (2) Method: We performed the experiments to check the ability of cryopreserved umbilical cord blood mononuclear cell-derived DCs (cryo CBMDCs) and their exosomes to prime allogeneic T cell proliferation and allogeneic peripheral blood mononuclear cell (alloPBMCs) cytotoxicity against A549 lung cancer cells. (3) Results: We found that both lung tumor cell lysate-pulsed DCs and their exosomes could induce allogeneic T cell proliferation. Moreover, alloPBMCs primed with tumor cell lysate-pulsed DCs and their exosomes have a greater cytotoxic activity against A549 cells compared to unprimed cells and cells primed with unpulsed DCs and their exosomes. (4) Conclusion: Tumor cell lysate-pulsed DCs and their exosomes should be considered to develop into a novel immunotherapeutic strategy-e.g., vaccines-for patients with lung cancer. Our results also suggested that cryo umbilical cord blood mononuclear cells source, which is a readily and available source, is effective for generation of allogeneic DCs and their exosomes will be material for vaccinating against cancer.

Factors Affecting Human Umbilical Cord Blood Quality Before Cryopreservation: The Importance of Birth Weight and Gestational Age.

Background: Umbilical cord blood (UCB) is a rich source of hematopoietic stem cells and is useful for the treatment of blood diseases. The cost of UCB storage is high; thus, it is necessary to evaluate the quality of UCB before collection and cryopreservation. Aim: This study aimed to determine the maternal and neonatal factors that influence UCB before selection for cryopreservation. Materials and Methods: The analysis included 403 processed UCB units. The effects of maternal characteristics including maternal age and delivery method and neonatal factors such as birth weight, gestation duration, and sex on UCB quality were determined based on the collected blood volume, total nucleated cell (TNC) count, and CD34+ cell count. Results: The neonatal birth weight influenced the collected blood volume, TNC count, and CD34+ cell count. Neonates with higher birth weights produced better quality UCB units because of increased collected blood volumes, TNC counts, and CD34+ cell counts. However, an increase in the gestational age from 35 to 41 weeks led to decreases in the collected blood volume and CD34+ cell count. Conclusion: These data may be useful for determining the optimal cord blood units for collection and cryopreservation and for advising pregnant women using private banking services.

Directed Evolution of Alcohol Dehydrogenase for Improved Stereoselective Redox Transformations of 1-Phenylethane-1,2-diol and Its Corresponding Acyloin.

Laboratory evolution of alcohol dehydrogenase produced enzyme variants with improved turnover numbers with a vicinal 1,2-diol and its corresponding hydroxyketone. Crystal structure and transient kinetics analysis aids in rationalizing the new functions of these variants.