The ins and outs of CCR7 in the thymus.
Although it is widely supposed that chemokines play a role in the thymus, most existing evidence is circumstantial. In this issue, two groups provide direct evidence that the chemokine receptor CCR7 is required for normal thymocyte migration (Ueno, T., F. Saito, D. Gray, S. Kuse, K. Hieshima, H. Nakano, T. Kakiuchi, M. Lipp, R. Boyd, and Y. Takahama. 2004. J. Exp. Med. 200:493-505; Misslitz, A., O. Pabst, G. Hintzen, L. Ohl, E. Kremmer, H. T. Petrie, and R. Forster. 2004. J. Exp. Med. 200:481-491). The two papers focus on distinct and opposite migration events, an early outward migration and a later inward migration. Together these papers provide a fascinating picture of the complex role of CCR7 in orchestrating thymocyte migration.
Witt
Colleen M
CM
Department of Molecular and Cell Biology, 471 Life Sciences Addition, University of California, Berkeley 94720, USA. cwitt@uclink.berkeley.edu
Robey
Ellen A
EA
D002465:Cell Movement / Q000502:physiology*; D006801:Humans; D008954:Models, Biological; D054400:Receptors, CCR7; D019707:Receptors, Chemokine / Q000378:metabolism* / Q000502:physiology; D013950:Thymus Gland / Q000502:physiology*
C515370:CCR7 protein, human; D054400:Receptors, CCR7; D019707:Receptors, Chemokine