Apoptosis mediated through CD45 is independent of its phosphatase activity and association with leukocyte phosphatase-associated phosphoprotein.
J Immunol
; 168(12): 6084-9, 2002 Jun 15.
Article
em En
| MEDLINE
| ID: mdl-12055218
ABSTRACT
Besides the well-recognized role of CD45 as a major player in TCR signaling, we and others have demonstrated that cross-linking of CD45 with mAbs can induce cell death in T lymphocytes. To investigate the role of CD45 phosphatase activity in apoptosis induction, we expressed either wild-type or phosphatase-dead CD45 molecules in a CD45-deficient BW5147 T cell line. We show here that the phosphatase activity of CD45 was not required for apoptosis triggering after cross-linking of the molecule. It is noteworthy that a revertant of the CD45-negative BW5147 cell line, expressing a truncated form of CD45 lacking most of the cytoplasmic domain, was also susceptible to CD45-mediated death. Moreover, we also demonstrate that leukocyte phosphatase-associated phosphoprotein expression is totally dispensable for CD45-mediated apoptosis to occur. Taken together, these results strongly suggest a role for the extracellular and/or the transmembrane portion of CD45 in apoptosis signaling, which contrasts with the previously reported functions for CD45 in T lymphocytes.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fosfoproteínas
/
Proteínas Tirosina Fosfatases
/
Apoptose
/
Antígenos Comuns de Leucócito
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Revista:
J Immunol
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Canadá