The Journal of Immunology, Vol 151, Issue 11 5984-5992, Copyright © 1993 by American Association of Immunologists

ARTICLES

Identification of a novel population of CD8 alpha+ beta- bone marrow- derived dendritic epidermal cells. This unique population is subsequently outnumbered by thymus-independent expansion of the CD8 alpha+ beta+ dendritic epidermal cells

J Hayakawa, T Shiohara, N Moriya, K Arahari, M Nagashima, H Yagita and H Ishikawa
Department of Dermatology, Kyorin University School of Medicine, Tokyo, Japan.

Maturation of some T cell populations has been suggested to occur in epithelial tissues. The CD8 molecule, which is expressed as heterodimers made of alpha/beta-chains on virtually all peripheral T cells, is preferentially expressed as homodimers made only of alpha- chains on a subset of CD8+ mouse gut intraepithelial lymphocytes, which arise from bone marrow (BM) precursors in a thymus-independent mechanism. This unique population of CD8 alpha+ beta- T cells, however, has not been identified in other lymphoid tissues in normal adult mice. Because our previous study demonstrated that reconstitution of thymectomized irradiated mice with T cell-depleted BM cells resulted in the appearance of CD8+, TCR-alpha beta+ dendritic epidermal cells (DEC) and suggested that a proportion of the BM-derived DEC may mature within the epidermis, we asked whether the unique phenotype of CD8 alpha+ beta- could be detected among the CD8+ BM-derived DEC. In this report for the first time we identified this unique population of CD8 alpha+ beta- cells among the DEC. Although this population comprised the predominant fraction of the BM-derived DEC in the early post-transfer period (2 to 3 mo), gradual shift from the CD8 alpha+ beta+ phenotypes occurred during the late post-transfer period (4 to 6 mo) independently of the presence of the thymus. Kinetic studies on the BM-derived DEC revealed that this phenotypic shift could be caused by the subsequent expansion of the CD8 alpha+ beta+ DEC. In contrast, the CD8 alpha+ beta- population was the major subset of the BM-derived intraepithelial lymphocytes throughout the entire observation period and the phenotypic shift with age was never observed. These results indicate that CD8 alpha+ beta- cells are preferentially detected on T cells that home to the epithelial tissues and that in the epidermis, but not in the gut epithelia, the subsequent expansion of the CD8 alpha+ beta+ DEC would dilute the high number of the CD8 alpha+ beta- cells.

This article has been cited by other articles:

				S. Takeuchi and S. I. Katz Use of interleukin 7 receptor-{alpha} knockout donor cells demonstrates the lymphoid independence of dendritic cells Blood, January 1, 2006; 107(1): 184 - 186. [Abstract] [Full Text] [PDF]

				H. Kitagaki, M. Kimishima, Y. Teraki, J. Hayakawa, K. Hayakawa, S. Fujisawa, and T. Shiohara Distinct In Vivo and In Vitro Cytokine Profiles of Draining Lymph Node Cells in Acute and Chronic Phases of Contact Hypersensitivity: Importance of a Type 2 Cytokine-Rich Cutaneous Milieu for the Development of an Early-Type Response in the Chronic Phase J. Immunol., August 1, 1999; 163(3): 1265 - 1273. [Abstract] [Full Text] [PDF]