CD38 expression on mouse T cells: CD38 defines functionally distinct subsets of alpha beta TCR+CD4-CD8- thymocytes.
We have examined CD38 expression on mouse lymphocytes using the rat mAb NIM-R5 and demonstrate that CD38 expression is restricted to approximately 8% of thymocytes. Although CD38 is absent from the majority of CD4+CD8- and CD4-CD8+ T cells, we detected a strong correlation between CD38 expression and alpha beta+CD4-CD8- T cells in the thymus, with nearly 80% of alpha beta TCR+CD4-CD8- thymocytes being CD38+. Using heat stable antigen (HSA) and CD38, we divided alpha beta+CD4-CD8- thymocytes into four subsets: HSA+CD38-, HSA-CD38hi, HSA-CD38low and HSA-CD38-. Two established characteristics of alpha beta TCR+CD4-CD8- cells, bias towards V beta 8.2 TCR expression and high levels of IL-4 production, were used to establish a possible relationship between the above thymocyte subsets. Our present data show that the HSA+CD38- subset is not biased towards V beta 8.2 TCR expression whereas the HSA-CD38- subset does show this bias (approximately 47%). Neither of these subsets make IL-4 upon CD3 mediated stimulation. In contrast, the CD38+ subsets are heavily biased toward V beta 8.2 expression and produce large amounts of IL-4 upon stimulation, particularly the CD38low cells. Taken together, these data suggest that these four subsets represent various stages of a possible differentiation pathway for alpha beta TCR+CD4-CD8- cells, with the HSA+CD38- subset being the most immature while the HSA-CD38low subset is the most functionally mature. These characteristics support the view that alpha beta TCR+CD4-CD8- T cells represent an independent lineage with a distinct, but as yet obscure, role in immunity.
Bean
A G
AG
DNAX Research Institute of Molecular and Cellular Biology, Inc., Palo Alto, CA 94304, USA.
Godfrey
D I
DI
Ferlin
W G
WG
Santos-Argumedo
L
L
Parkhouse
M E
ME
Howard
M C
MC
Zlotnik
A
A
D036541:ADP-ribosyl Cyclase; D051997:ADP-ribosyl Cyclase 1; D000818:Animals; D015703:Antigens, CD / Q000096:biosynthesis* / Q000276:immunology; D000943:Antigens, Differentiation / Q000096:biosynthesis* / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D002478:Cells, Cultured; D005434:Flow Cytometry; D008297:Male; D008562:Membrane Glycoproteins; D051379:Mice; D008807:Mice, Inbred BALB C; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000145:classification*; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology
D015703:Antigens, CD; D000943:Antigens, Differentiation; D017252:CD3 Complex; D008562:Membrane Glycoproteins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D036541:ADP-ribosyl Cyclase; C498155:Cd38 protein, mouse; D051997:ADP-ribosyl Cyclase 1