T cell lineage determination precedes the initiation of TCR beta gene rearrangement |
| |
Authors: | Masuda Kyoko Kakugawa Kiyokazu Nakayama Toshinori Minato Nagahiro Katsura Yoshimoto Kawamoto Hiroshi |
| |
Institution: | Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, Japan. |
| |
Abstract: | Loss of dendritic cell potential is one of the major events in intrathymic T cell development, during which the progenitors become determined to the T cell lineage. However, it remains unclear whether this event occurs in synchrony with another important event, TCRbeta chain gene rearrangement, which has been considered the definitive sign of irreversible T cell lineage commitment. To address this issue, we used transgenic mice in which GFP expression is controlled by the lck proximal promoter. We found that the double-negative (DN) 2 stage can be subdivided into GFP- and GFP+ populations, representing functionally different developmental stages in that the GFP-DN2, but not GFP+DN2, cells retain dendritic cell potential. The GFP+DN2 cells were found to undergo several rounds of proliferation before the initiation of TCRbeta rearrangement as evidenced by the diversity of D-Jbeta rearrangements seen in T cells derived from a single GFP+DN2 progenitor. These results indicated that the determination step of progenitors to the T cell lineage is a separable event from TCRbeta rearrangement. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|