Send to

Choose Destination
Immunity. 2008 Dec 19;29(6):888-98. doi: 10.1016/j.immuni.2008.10.008. Epub 2008 Nov 27.

PlexinD1 glycoprotein controls migration of positively selected thymocytes into the medulla.

Author information

Laboratory of Immunobiology, Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA 02115, USA.


Precise intrathymic cell migration is important for thymocyte maturation and organ architecture. The orchestration of thymocyte trafficking, however, is not well understood at a molecular level. Here, we described highly regulated plexinD1 expression on CD4+CD8+ double positive (DP) thymocytes. PlexinD1 expression was further affected by the engagement of T cell receptor complex. Activation of plexinD1 via the ligand, semaphorin 3E, repressed CCL25 chemokine signaling via its receptor CCR9 in CD69+ thymocytes. In the absence of plexinD1, CD69+ thymocytes remained in the cortex, maturing to form ectopic single positive (SP) thymocyte clusters in Plxnd1-deficient fetal liver cell-transplanted mice. As a consequence, the boundary between DP and SP thymocytes at corticomedullary junctions was disrupted and medullary structures formed under the thymic capsule. These results demonstrate the importance of plexinD1 in directing migration of maturing thymocytes via modulation of biological responses to chemokine gradients.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center