In:
The Journal of Immunology, The American Association of Immunologists, Vol. 168, No. 11 ( 2002-06-01), p. 5434-5440
Abstract:
TCR internalization takes place both in resting T cells as part of constitutive TCR cycling, after PKC activation, and during TCR triggering. It is still a matter of debate whether these pathways represent distinct pathways. Thus, some studies have indicated that ligand-induced TCR internalization is regulated by mechanisms distinct from those involved in constitutive internalization, whereas other studies have suggested that the ligand-induced TCR internalization pathway is identical with the constitutive pathway. To resolve this question, we first identified requirements for constitutive TCR cycling. We found that in contrast to PKC-induced TCR internalization where both CD3γ-S126 and the CD3γ leucine-based internalization motif are required, constitutive TCR cycling required neither PKC nor CD3γ-S126 but only the CD3γ leucine-based motif. Having identified these requirements, we next studied ligand-induced internalization in cells with abolished constitutive TCR cycling. We found that ligand-induced TCR internalization was not dependent on constitutive TCR internalization. Likewise, constitutive internalization and recycling of the TCR were independent of an intact ligand-induced internalization of the TCR. In conclusion, ligand-induced TCR internalization and constitutive cycling of the TCR represents two independent pathways regulated by different mechanisms.
Type of Medium:
Online Resource
ISSN:
0022-1767
,
1550-6606
DOI:
10.4049/jimmunol.168.11.5434
Language:
English
Publisher:
The American Association of Immunologists
Publication Date:
2002
detail.hit.zdb_id:
1475085-5