esponse.

lymphocyterecirculation: Lymphocytes are continuously moving through the blood and lymphaticsbetween different lymphoid organs, and when activated, to specific inflammatorytissues.

immunologicsynapse:The highly ordered structures formed between APC and T lymphocytes, in which alarge cluster of TCR and MHC-peptide complexes are surrounded by a ring of celladhesion molecules.

Tcell epitope: Antigenic determinants recognized by T cells are called T cellepitope. They are mostly peptides with 8-23 amino acids and can appear anywherein the antigen, most of them are linear epitopes, and need MHC and APCpresentation to activate B cells.

Bcell epitope: Antigenic determinants recognized by B cells are called B cellepitope. They are mostly polysaccharides and lipids or peptides with 5-15 aminoacid residues, and most of them are conformational epitopes on the surface ofthe antigen.

CK:CK are low molecular weight proteins produced and secreted by many differentcell types, and play an important part in immune and inflammatory response,

ADCC:antigen-dependent cell-mediated cytotoxicity, The Fc fragment of the antibodyattached to the antigen can combine with the FcR on the NK cell and macrophageand induce the release of cytotoxic substances like perforin and granzyme.

TSA:tumor-specific antigen, antigens that are only expressed on tumor cells but noton normal cells.

lymphocytehoming: The directed migration of circulating lymphocytes into particulartissue sites It is regulated by the selective expression of endothelial adhesionmolecules and chemokines and is realized by the interaction of the addressinand lymphocyte homing receptor.

PAMP:pathogen-associated molecular pattern, the highly conserved structures sharedby particular groups of microbial pathogens, which can be recognized by theinnate immune cells, like LPS, LTA, etc.

idiotype:Different Igs produced by different B lymphocytes possess unique structuresrespectively in the hypervariable regions, these unique structures of the Igsare called isotypes.

MHC:major histocompatibility complex, are a group of linked genes in some of thechromosome in human and other mammals that encode for MHS and is associatedwith immune response, immune regulation, cell-cell adhesion and allograftrejection.

immuneignorance: is a form of lymphocyte unresponsiveness in which the self antigensare ignored by the immune system, but the lymphocytes specific for that antigenremain viable and functional.

AICD:activation-induced cell death.
T:Repeated challenge of the lymphocytes withconsistent antigens results in the death of that cell, by a process ofapoptosis.
B:B lymphocytes are actively eliminated through the interaction of FasL on Thcells and Fas on the activated B cells.

mAb:monoclonal antibody, are antibodies produced by a single B cell clone and bearunique specificity for antigen.

isotypicexclusion: In an individual B cells, only on of the two types of light chaingenes are expresses. This ensures that a single B cell has only one kind oflight chain.

granzyme:is a kind of cytotoxic substance produced by NK or Tc which can causehydrolysis of the intracellular proteins and lead to apoptosis.

peripheraltolerance: Mature lymphocytes in the peripheral lymphoid organs encounter selfor non-self antigens and form tolerance to tissue-specific antigens.

antigenicmodulation: The decrease or loss of tumor surface antigens caused by humoralimmune responses against tumors.

MHCrestriction: TCR can only recognize peptides presented by self MHC molecules.That is to say, the interaction between APC and T lymphocytes is restricted byself MHC molecules.

ITAM:is a conserved structure which has two repeated sequence tyr-X-X-leu in manymolecules in the immune system, and participate in the activation signaltransduction.