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.