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FSL Constructs: A Simple Method for Modifying Cell/Virion Surfaces with a Range of Biological Markers Without Affecting their Viability
Published on: August 5, 2011
FasL expression and reverse signalling
M Lettau1, M Paulsen, D Kabelitz
1Institute of Immunology, University Hospital Schleswig-Holstein Campus Kiel, Michaelisstr. 5, D-24105 Kiel, Germany.
Abstract:
FasL plays a central role in the induction of apoptosis within the immune system. It mediates activation-induced cell death (AICD) of T lymphocytes and contributes to the cytotoxic effector function of T and NK cells. Moreover, FasL is discussed as direct effector molecule for the establishment of immune privilege and tumour survival. Besides its death-promoting activity, FasL has been implicated in reverse signalling and might thus also play a role in T cell development and selection and the modulation of T cell activation. Considering these diverse functions, the overall FasL expression has to be tightly controlled to avoid unwanted damage. Based on an activation-associated transcriptional control, several post-transcriptional processes ensure a safe storage, a rapid mobilisation, a target-directed activity and a subsequent inactivation. Over the past years, the identification and characterisation of FasL-interacting proteins provided novel insight into the mechanisms of FasL transport, processing and reverse signalling, which might be exemplary also for the other members of the TNF family.
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