Although bone marrow (BM) is the main site of natural killer (NK)-cell development in adult mice, recent studies have identified a distinct thymic-dependent NK pathway, implicating a possible close link between NK- and T-cell development in adult hematopoiesis. To investigate whether a potential NK-/T-lineage restriction of multipotent progenitors might take place already in the BM, we tested t...

Background & Objective: Although the antigen expression patterns of acute lymphoblastic leukemia (ALL) are well known, this study attempted to evaluate commonly used immune markers for immunophenotyping of acute leukemia to set the minimum of necessary diagnostic panels by flow cytometry. Methods: This study evaluated 89 patients referred from all over th...

Neonatal T cell-B cell collaboration was investigated utilizing a system of T cell-dependent polyclonal B cell activation and Ig secretion. In this system, T cells activated by immobilized anti-CD3 provide a potent stimulus for Ig production by adult lymphocytes. By contrast, anti-CD3 stimulation of cord blood lymphocytes generated minimal numbers of Ig-secreting cells. Ig production by neonata...

T-cell development depends upon interactions between thymocytes and thymic epithelial cells (TECs). The engagement of delta-like 4 (DL4) on TECs by Notch1 expressed by blood-borne BM-derived precursors is essential for T-cell commitment in the adult thymus. In contrast to the adult, the earliest T-cell progenitors in the embryo originate in the fetal liver and migrate to the nonvascularized fet...