The fate of CD4-8- T cell receptor-alpha beta+ thymocytes.
CD4-8- TCR-alpha beta+ thymocytes represent a distinct population whose fate and function have remained a mystery. We show here that this thymocyte subset bears NK1, a surface Ag previously thought to be expressed exclusively by TCR- NK cells. Analysis of peripheral lymphocytes for the coexpression of TCR-alpha beta and NK1 revealed a subset with similar characteristics to the NK1+ thymocytes: a large fraction that are CD4-8- and a skewed TCR repertoire in which V beta 8 is overrepresented. Thymus transplant experiments into congenically marked athymic (nude) mice revealed that the NK1+TCR alpha beta+ subset was exclusively thymus derived and represented a distinct subset from the thymus-independent NK1+TCR- population. Finally, the NK1+TCR alpha beta+ population preferentially localizes to the bone marrow. These results demonstrate that this T cell subset is exported to the periphery after developing in the thymus. Their unique surface Ag expression and tissue localization suggest an immune function distinct from classical T cells.
Levitsky
H I
HI
Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Golumbek
P T
PT
Pardoll
D M
DM
D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D001854:Bone Marrow Cells; D051379:Mice; D008810:Mice, Inbred C57BL; D009928:Organ Specificity; D011948:Receptors, Antigen, T-Cell / Q000502:physiology*; D016693:Receptors, Antigen, T-Cell, alpha-beta; D013154:Spleen / Q000166:cytology; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology
D000954:Antigens, Surface; D011948:Receptors, Antigen, T-Cell; D016693:Receptors, Antigen, T-Cell, alpha-beta