Cancer Immune Therapy Edited by G. Stuhler and P. Walden ...

duce variably inhibitory or activating signals after binding to MHC class I or Ib molecules.
The absence of MHC expression may trigger NK cell activation.
Neutrophil
A phagocytic polymorphonuclear leukocyte that can ingest and kill invading microorganisms.
They play important parts in inflammatory reactions both in the removal
of microorganisms and aged and damaged cells, and as a source for inflammatory
agents such as chemokines, cytokines, leukotrienes and other lipid mediators of inflammation.
Suicide gene
Inducible gene that codes for a protein which mediates cell death. One of the bestknown
examples is the herpes simplex virus thymidine kinase (HSV-tk) which converts
the non-toxic prodrug gancyclovir into its cytotoxic phosphorylated form.
Programmed cell death
see Apoptosis.
Glossary
T cell receptor (TCR)
Antigen receptor of T lymphocytes. The TCR consists of a disulfide-bonded ab or gd
heterodimer expressed at the cell surface in association with the CD3 molecular
complex as the signal-transducing unit of the receptor. The genes for the TCR are rearranged
from the germline V, D, and J elements during the ontology of the T lymphocyte
to form the clonotypic genes and gene products. The ligands of the TCR are
MHC/peptide complexes.
T lymphocyte (T cell)
Lymphocyte of the thymic linage which are subdivided into CD8-expressing cytolytic
T lymphocytes (CTL) and CD4-expressing regulatory helper T cells. The precursors of T
cells originate in the bone marrow and migrate as CD4/CD8 double-positive cells
into the thymus where they differentiate into the mature T lymphocyte types. During
thymic differentiation, the T cell receptor (TCR) genes are rearranged. T cells are
selected to propagate whose TCR are MHC-restricted (positive selection) and are
eliminated by apoptosis when they bind MHC/peptide complexes with high affinity;
thus, they are potentially autoreactive (negative selection, see Central tolerance). T
cells as regulator and effector T cells are key instruments of the adaptive immune
system. Unlike B lymphocytes, T lymphocytes recognize their epitopes as complexes
with MHC class I or I molecules.
T body
Cytotoxic T lymphocyte genetically engineered to express a chimeric antibody/receptor
surface molecule with specificity for an antigen on the surface of tumor cells.
Usually the chimeric receptor consists of single-chain antibody fragments with the
desired specificity fused to CD3z or Fc receptor g as signal transduction domains.
T bodies have been developed with a number of different specificities. Anti-G250
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