Peripheral CD4+ T cell maturation recognized by increased expression of Thy-1/CD90 bearing the 6C10 carbohydrate epitope.
The SM6C10 IgM autoantibody recognizes a surface determinant, 6C10, that is highly expressed on all immature thymocytes. In contrast, its expression on peripheral T cells appears developmentally regulated, i.e., absent from most naive T cells in spleen of neonatal mice, but expressed on 40-80% of naive CD4+ T cells in adult. In this paper, we demonstrate that SM6C10 recognizes a carbohydrate epitope on the Thy-1 glycoprotein using immunoprecipitation analysis, by binding to affinity-purified Thy-1 in an ELISA, and by sensitivity to N-glycosidase-F treatment. Retroviral Thy-1 gene transduction experiments into Thy-1- variant T cell lines and a pro-B cell line provide evidence that 6C10 glycosylated Thy-1 expression is not restricted to T cells but depends on the recipient cell. Therefore, differences in 6C10 levels among Thy-1+ T cells in mice likely reflect developmental regulation of posttranslational modification of the Thy-1 glycoprotein. The ability of naive CD4+ T cells to respond to anti-Thy-1 stimulation increases from neonate to adult, and 6C10- naive cells from adult mice respond poorly compared with 6C10+ cells, similar to the cells in neonatal mice. These results suggest that there is functional maturation by peripheral CD4+ T cells that coincides with 6C10 glycosylated Thy-1 up-regulation, and natural autoantibody recognizes this 6C10 carbohydrate epitope.
Gui
M
M
Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
Wiest
D L
DL
Li
J
J
Kappes
D
D
Hardy
R R
RR
Hayakawa
K
K
D000818:Animals; D001323:Autoantibodies / Q000378:metabolism; D001666:Binding Sites, Antibody; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology / Q000378:metabolism*; D002241:Carbohydrates / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D002460:Cell Line; D004591:Electrophoresis, Polyacrylamide Gel; D018984:Epitopes, T-Lymphocyte / Q000096:biosynthesis*; D006023:Glycoproteins / Q000096:biosynthesis; D016130:Immunophenotyping; D051379:Mice; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008970:Molecular Weight; D011233:Precipitin Tests; D020033:Protein Isoforms / Q000096:biosynthesis; D018800:Thy-1 Antigens / Q000096:biosynthesis* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D014162:Transfection; D015854:Up-Regulation / Q000276:immunology
D001323:Autoantibodies; D002241:Carbohydrates; D018984:Epitopes, T-Lymphocyte; D006023:Glycoproteins; D020033:Protein Isoforms; D018800:Thy-1 Antigens