Recent findings in cord blood described by researchers from University of Tsukuba
2009 JUL 13 - (NewsRx.com) -- According to recent research from Tsukuba, Japan, "The development of NK cells from hematopoietic stem cells is thought to be dependent on IL-15. In this study, we demonstrate that stimulation of human cord blood CD34(+) cells by a Notch ligand, Delta4, along with IL-7, stem cell factor, and Fms-like tyrosine kinase 3 ligand, but no IL-15, in a stroma-free culture induced the generation of cells with characteristics of functional NK cells, including CD56 and CD161 Ag expression, IFN-gamma secretion, and cytotoxic activity against K562 and Jurkat cells." "Addition of gamma-secretase inhibitor and anti-human Notchl Ab to the culture medium almost completely blocked NK cell emergence. Addition of anti-human IL-15-neutralizing Ab did not affect NK cell development in these culture conditions. The presence of IL-15, however, augmented cytotoxicity and was required for a more mature NK cell phenotype. CD56(+) cells generated by culture with IL-15, but without Notch stimulation, were negative for CD7 and cytoplasmic CD3, whereas CD56(+) cells generated by culture with both Delta4 and IL-15 Were CD7(+) and cytoplasmic CD3(+) from the beginning and therefore more similar to in vivo human NK cell progenitors. Together, these results suggest that Notch signaling is important for the physiologic development of NK cells at differentiation stages beyond those previously postulated," wrote K. Haraguchi and colleagues, University of Tsukuba. The researchers concluded: "Journal of Immunology, 2009, 182:6168-6178." Haraguchi and colleagues published their study in the Journal of Immunology (Notch Activation Induces the Generation of Functional NK Cells from Human Cord Blood CD34-Positive Cells Devoid of IL-15. Journal of Immunology, 2009;182(10):6168-6178). For additional information, contact S. Chiba, University of Tsukuba, Dept. of Clinic & Experimental Hematology, Graduate School Comprehensive Human Science, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan. Publisher contact information for the Journal of Immunology is: American Association Immunologists, 9650 Rockville Pike, Bethesda, MD 20814, USA. Keywords: Japan, Tsukuba, Blood Transfusion, Cord Blood, Cytotoxic Activity, Drug Development, Enzyme Research, Hematology, Hematopoietic, Immunology, Kinase, Medical Device, Proteins, Proteomics, Secretase, Stem Cell Research, Therapy, Transfusion Medicine, Treatment, Tyrosine Kinase, University of Tsukuba. This article was prepared by Stem Cell Week editors from staff and other reports. Copyright 2009, Stem Cell Week via NewsRx.com.
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