Summary
This study analysed 65 children who were prospectively registered between 1999 and 2008 and fulfilled the World Health Organization 2008 criteria of refractory cytopenia of childhood (RCC). First‐line therapy was determined by the treating physicians: 25 patients received immunosuppressive therapy (IST), 12 patients received haematopoietic stem cell transplantation (HSCT) and one patient received intensive chemotherapy. The remaining 27 patients were followed without treatment for more than 2 years (watch and wait; WW). In the WW group, 18 patients had stable disease without further intervention. Thirteen of 29 patients (45%) who ended up receiving IST showed response. The combination of ciclosporin and antithymocyte globulin was not shown to be superior to ciclosporin alone with regard to response rate or survival. Of 28 patients who ended up undergoing HSCT, 17 patients are alive in complete remission, whereas nine patients died mostly due to transplantation‐related mortality. The 5‐year overall survival for all patients was 82 ± 5%. Eight patients suffered from disease progression. Patients with monosomy 7 or multilineage‐dysplasia had a significantly higher incidence of disease progression. This analysis revealed heterogeneity in the clinical course of RCC, varying from those who remained stable for long periods to those who progressed to advanced disease.
The morphological discrimination of leukemic from non-leukemic T cells is often difficult in adult T-cell leukemia (ATL) as ATL cells show morphological diversity, with the exception of typical ''flower cells.'' Because defects in the expression of CD3 as well as CD7 are common in ATL cells, we applied multi-color flow cytometry to detect a putative leukemia-specific cell population in the peripheral blood from ATL patients. CD4 + CD14) cells subjected to two-color analysis based on a CD3 vs CD7 plot clearly demonstrated the presence of a CD3 dim CD7 low subpopulation in each of nine patients with acute-type ATL. The majority of sorted cells from this fraction showed a flower cell-like morphology and carried a high proviral load for the human T-cell leukemia virus type 1 (HTLV-I). Genomic integration site analysis (inverse long-range PCR) and analysis of the T cell receptor Vb repertoire by flow cytometry indicated that the majority of leukemia cells were included in the CD3 dim CD7 low subpopulation. These results suggest that leukemic T cells are specifically enriched in a unique CD3 dim CD7 low subpopulation of CD4 + T cells in acute-type ATL. (Cancer Sci 2011; 102: 569-577)
We propose a novel method for the efficient production of hematopoietic progenitors from human embryonic stem cells (hESC) via coculture with murine fetal liver-derived stromal cells, in which embryonic hematopoiesis dramatically expands at midgestation. We generated various hematopoietic progenitors in coculture, and this hematopoietic activity was concentrated in cobblestone-like cells derived from differentiated hESC. The cobblestone-like cells mostly expressed CD34 and retained an endothelial cell potential. They also contained hematopoietic colony-forming cells, especially erythroid and multilineage colony-forming cells at high frequency. The multipotential hematopoietic progenitors abundant among the cobblestone-like cells produced almost all types of mature blood cells, including adult-type alpha-globin-expressing erythrocytes and tryptase/chymase double-positive mast cells. These progenitors showed neither the immature properties of ESC nor the potential to differentiate into endoderm and ectoderm at a clonal level. The coculture system developed for hESC can provide a novel source of hematopoietic and blood cells for applications in cellular therapy and drug screening.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.