U5A2-13, an antigen originally found on mouse NK-like T cells, is an early inducible cell surface antigen during lymphoid activation.
We have previously reported a monoclonal antibody (mAb), U5A2-13 mAb, which originally recognizes a phenotypically and functionally similar population of natural killer (NK)-like T cells. In this study, we found that U5A2-13 antigen (U5A2-13) was expressed not only on NK-like T cells but also on T and B cells during activation. In contrast to the low levels of U5A2-13 on freshly harvested T and B cells, the activation of these cells by various stimuli resulted in high levels of expression of U5A2-13 in vitro and in vivo. Similar to CD69, U5A2-13 is also expressed in most mouse lymphoid cell lines but not in nonhematopoietic cells. U5A2-13 on T cells reached maximal expression by 24h after stimulation and returned to baseline levels after 3 days. However, U5A2-13 differed from CD69 since its expression profile was different on CD4(+)- and CD8(+)-activated T cells, phorbol ester-activated EL-4 cells, and activated splenocytes in CD69-deficient mice. In addition, immunoprecipitation study indicated that U5A2-13 is not identical to CD69. Importantly, the U5A2-13-positive population of CD4(+) T cells exhibited significant levels of cytokine producing activity upon stimulation. Overall, U5A2-13 is an early inducible cell surface antigen that could be involved in lymphocyte activation.
Pharmacology Division, National Cancer Center Research Institute, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan. kakazu@sapmed.ac.jp
Kazunori
K
Kato
Yoshinori
Y
Ikarashi
Toshiaki
T
Sugahara
Atsushi
A
Yasumoto
David
D
Sancho
Mitsuzi
M
Yoshida
Yoichi
Y
Takaue
Yoshiro
Y
Kobayashi
Francisco
F
Sánchez-Madrid
Hiro
H
Wakasugi
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015703:Antigens, CD / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism; D000954:Antigens, Surface / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D002460:Cell Line; D002478:Cells, Cultured; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D007694:Killer Cells, Natural / Q000276:immunology; D007700:Kinetics; D037181:Lectins, C-Type; D008213:Lymphocyte Activation; D051379:Mice; D008810:Mice, Inbred C57BL; D019463:Mice, Inbred MRL lpr; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014407:Tumor Cells, Cultured; D000099192:CD69 Antigens
D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D016207:Cytokines; D037181:Lectins, C-Type; D000099192:CD69 Antigens