摘要
While murine B- and T-Iymphopoiesis require overlapping molecules, they occur in separate organs: the bone marrow (BM) and the thymus, respectively. The BM microenvironment is incapable of supporting T-Iymphopoiesis because of insufficient interactions of Notch1 with delta-like ligand (DII). Notch1/DII interactions also play a role in the suppression of B-lymphopoiesis in the thymus. However, it is still unclear whether the Notch1/DII interaction alone explains why the thymus does not support B-lymphopoiesis. In this study, we compared the precursor population colonizing the thymus with that in the BM by culturing them on stromal cells expressing abundant DII1. We demonstrated that Flt3(+) I17r(+) B220(+) Cd19(+) BM cells gave rise to B cells under this condition. We defined them as resistant to DII1. In the thymus, DII1-resistant cells were undetectable. This suggested that the absence of DII1-resistant cells might explain the absence of B-lymphopoiesis in the thymus.
- 出版日期2012-1-6