Effect of IL-21 on NK cells derived from different umbilical cord blood populations.

IL-21 plays a role in the proliferation and maturation of NK cells developed from hematopoietic stem cells. In this study, we found that IL-21, in the presence of physiological concentration of hydrocortisone (HC), has a significant impact on the functions of NK cells derived from umbilical cord blood (CB) populations. We demonstrate that IL-21, in combination with Flt3-ligand, IL-15 and HC, induces high proliferative responses and, apart from enhancing NK-mediated cytotoxicity, it also induces a significant increase in lymphokine-activated killer activity of CB/CD34+-derived CD56+ cells.

First-trimester NRBC count in maternal circulation: correlation with doppler ultrasound studies.

This study aimed to determine whether the number of nucleated red blood cells (NRBCs) in maternal circulation during the first trimester of pregnancy could identify pregnancies that will have an anomalous Doppler in the second trimester. A total of 85 blood samples were obtained at 11-14 weeks of gestation with mean uterine arterial perfusion index >1.6, as noted by Doppler ultrasonography.