Therapeutic Cancer Vaccines-T Cell Responses and Epigenetic Modulation.

There is great interest in developing efficient therapeutic cancer vaccines, as this type of therapy allows targeted killing of tumor cells as well as long-lasting immune protection. High levels of tumor-infiltrating CD8+ T cells are associated with better prognosis in many cancers, and it is expected that new generation vaccines will induce effective production of these cells. Epigenetic mechanisms can promote changes in host immune responses, as well as mediate immune evasion by cancer cells. Here, we focus on epigenetic modifications involved in both vaccine-adjuvant-generated T cell immunity and cancer immune escape mechanisms. We propose that vaccine-adjuvant systems may be utilized to induce beneficial epigenetic modifications and discuss how epigenetic interventions could improve vaccine-based therapies. Additionally, we speculate on how, given the unique nature of individual epigenetic landscapes, epigenetic mapping of cancer progression and specific subsequent immune responses, could be harnessed to tailor therapeutic vaccines to each patient.

Influence of mode of birth and collection on WBC yields of umbilical cord blood units.

BACKGROUND: The aim of this study was to determine the influence of mode of birth and umbilical cord blood (CB) collection before (in utero) or after delivery of the placenta (ex utero) on total number of WBCs and CD34+ cells in CB units. STUDY DESIGN AND METHODS: Consecutively donated, banked CB units were assessed for net volume, WBC concentration, total number of WBCs, proportion of CD34+ cells, and total number of CD34+ cells. These parameters were then correlated with the mode of birth and the mode of CB collection relative to the delivery of the placenta. RESULTS: A significantly higher CB volume was seen following cesarean section (n = 61) than following vaginal delivery (n = 157; median volume, 76 vs. 63 mL, respectively; p < 0.0001). In contrast, CB from vaginal delivery had a significantly higher WBC concentration compared with CB from cesarean section (medians, 17.1 x 10(9) and 13.6 x 10(9) WBCs/L, respectively; p < 0.0001). The mode of birth did not influence the proportion of CD34+ cells. A correlation was demonstrated between the total number of CD34+ cells and the total number of WBCs. As a consequence of the opposing effects on volume and WBC counts by cesarean section and vaginal delivery, there were no significant differences in the total number of WBCs or CD34+ cells for the CB units with mode of delivery in this study. No significant differences were found in CB with mode of CB collection (in utero [n = 58] or ex utero [n = 99]) following vaginal delivery. CONCLUSIONS: The mode of birth influences the CB WBC concentration and volume collected and should be taken into consideration for establishing any acceptance limits for CB units to be banked. There were no differences in CB with in utero or ex utero collections.