Medical Immunology

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Medical Immunology
??????????? Terminology of Medical Immunology
?????????? 2003.6.1
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Antigen
Antigen. A molecule which reacts with preformed
???? antibody and the specific receptors on T
and B cells. Antigens Substances that are
recognized by the immune system and induce an
immune reaction.
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Epitopes
Epitopes??. The parts of an antigen which
contact the antigen-binding sites of an antibody
or the T-cell receptor. Epitopes or Antigenic
Determinants Sites on an antigen that interact
with specific antibodies.
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Superantigens

• Superantigens. Antigens which stimulate clones of
  T cells which have different antigen specificity,
  but which use the same TCR V genes.
• Superantigens Microbial antigens that have in
  common an extremely potent??? activating effect
  on T-cells that bear a specific variable region.
  Superantigens cross-link the variable region with
  class II MHC proteins regardless of the peptide
  binding in the T-cell receptor's pocket. The
  result is a transient?? expansion and
  subsequent death and anergy??? of the T-cells
  with the appropriate variable regions.

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T-dependent/T-independent Antigens
T-dependent antigens require immune recognition
by both T and B cells to produce an immune
response. T-independent antigens can directly
stimulate B cells to produce specific antibody.
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Antibody
Antibody. A molecule produced by animals in
response to antigen which has the particular
property of combining specifically with the
antigen which induced its formation. Antibodies
Immunoglobulin molecules having a specific amino
acid sequence by virtue of ?? which they
interact only with the antigen that induced their
synthesis in cells of the lymphoid series
(especially PLASMA CELLS), or with an antigen
closely related to it.
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Allotype
Allotype????. The protein of an allele????
which may be detectable as an antigen by another
member of the same species?. Immunoglobulin
Allotypes Hereditary serologic types based on
antigenic differences in the light and heavy
chains of immunoglobulins due to allelic genes in
the gene loci ?? coding ?? the chains. The
Inv system applies to the kappa light chains, the
Gm system applies to the heavy chains of IgG.
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Antibody Diversity
Antibody Diversity??? The phenomenon of
immense variability characteristic of antibodies,
which enables the immune system to react
specifically against the essentially unlimited
kinds of ANTIGENS it encounters??.
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C domains
C domains??. The constant domains of antibody
and the T-cell receptor. These domains do not
contribute to the antigen-binding site and show
relatively little variability between receptor
molecules. Constant?? regions. The relatively
invariant?? parts of immunoglobulin heavy and
light chains, and the alpha, beta, gamma and
delta chains of The T-cell receptor.
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Hypervariable region
Hypervariable region. The most variable areas of
the V domains of immunoglobulin and T-cell
receptor chains. These regions are clustered at
the distal portion of the V domain and contribute
to the antigen-binding site.
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Idiotype
Idiotype. The antigenic characteristic of the V
region of an antibody. Immunoglobulin Idiotypes
Unique, genetically controlled determinants
present on antibodies whose specificity is
limited to a single group of proteins (e.g.,
another antibody molecule or an individual
myeloma protein). The idiotype appears to
represent the antigenicity of the antigen-binding
site of the antibody and to be genetically
codetermined with it. The idiotypic determinants
have been precisely located to the immunoglobin
VARIABLE REGION of both immunoglobin polypeptide
chains.
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Immune Sera
Serum that contains antibodies. It is obtained
from an animal that has been immunized either by
antigen injection or infection with
microorganisms containing the antigen.
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Immunoglobulin supergene family (IgSF)
Molecules which have domains homologous?? to
those seen in immunoglobulins, including MHC
class I and II molecules, the T-cell receptor,
CD2, CD3, CD4, CD5, ICAMs, VCAM and some of the
Fc receptors.
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Monoclonal Antibodies
Antibodies produced by clones of cells such as
those isolated after hybridization?? of
activated B lymphocytes with neoplastic? cells.
These hybrids??? are often referred to as
hybridomas.??? Hybridoma. Cell line created in
vitro by fusing two different cell types, usually
lymphocytes, one of which is a tumour cell.
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Opsonization
A process by which phagocytosis???? is
facilitated?? by the deposition?? of opsonins
(???,e.g. antibody and C3b) on the antigen.
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Complement
A heat-sensitive complex system in fresh human
and other sera which, in combination with
antibodies, is important in the host defense
mechanism against invading organisms. At least 20
distinct?? serum proteins operate within the
complement system.
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Alternative pathway
The activation pathways of the complement system
involving C3 and factors B, D, P, H and I, which
interact in the vicinity?? of an activator
surface to form an alternative pathway C3
convertase???. The complement activation
sequence initiated by the activation of
complement factor C3, which is triggered?? by
the interaction of microbial polysaccharides??
and properdin??? without participation of an
antigen-antibody reaction.
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Amplification loop
The alternative complement activation pathway,
which acts as a positive feedback loop when C3 is
split?? in the presence of an activator
surface.  
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C3 convertases
The enzyme complexes C3b, 3b and C4b2a that
cleave complement C3. The enzyme which in both
the classical and alternate complement pathways
cleaves?? complement 3 into anaphylatoxin
????(C3a) and C3b.
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MBL pathway Lectin???pathway.
A pathway of complement activation, initiated by
mannan????-binding lectin (MBL), which
intersects?? the classical pathway.
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Membrane attack complex (MAC)
The assembled?? terminal complement components
C5b-C9 of the lytic??? pathway which becomes
inserted into cell membranes.
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Cytokines
A generic term for soluble molecules which
mediate interactions between cells. Non-antibody
proteins secreted by inflammatory ?? leukocytes
and some non-leukocytic cells, that act as
intercellular mediators??. They differ from
classical hormones in that they are produced by a
number of tissue or cell types rather than by
specialized glands. They generally act locally in
a paracrine??? or autocrine??? rather than
endocrine??? manner.
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CSF
CSFs (colony stimulating factors). A group of
cytokines which control The differentiation of
hemopoietic stem cells ?????. CSFs
Glycoproteins??? found in a subfraction??? of
normal mammalian plasma and urine. They stimulate
the proliferation?? of bone marrow cells in
agar?? cultures and the formation of colonies
of granulocytes??? and/or macrophages. The
factors include IL-3 G-CSF and GM-CSF.
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IFN
Interferons (IFNs). A group of molecules involved
in signalling between cells of the immune system,
and in protection against viral infections.
Interferons Proteins secreted by vertebrate
cells in response to a wide variety of inducers.
They confer resistance against many different
viruses, inhibit proliferation of normal and
malignant??? cells, impede?? multiplication
of intracellular parasites, enhance macrophage
and granulocyte phagocytosis, augment natural
killer cell activity, and show several other
immunomodulatory functions.
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IL
Interleukins (IL-l to IL-22). A group of
molecules involved in signaling??? between
cells of the immune system. Interleukins
Soluble factors which stimulate growth-related
activities of leukocytes as well as other cell
types. They enhance cell proliferation and
differentiation, DNA synthesis, secretion of
other biologically active molecules and responses
to immune and inflammatory stimuli????.
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LKs
Lymphokines. A generic term for molecules other
than antibodies which are involved in signalling
between cells of the immune system and are
produced by lymphocytes (cf. interleukins).
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tumour necrosis factor
TNF. A cytokine released by activated macrophages
that is structurally related to lymphotoxin????
released by activated T cells. TNFs. A group of
proinflammatory?? cytokines encoded?? within
the MHC. TNF Serum glycoprotein produced by
activated macrophages and other mammalian
mononuclear leukocytes. It has necrotizing???
activity against tumor cell lines??? and
increases ability to reject tumor transplants.
Also known as TNF-alpha, it is only 30
homologous?? to TNF-beta (Lymphotoxin), but
they share two receptors.
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CD

• CD Antigens Differentiation antigens????
  residing?? on mammalian leukocytes. CD stands
  for cluster? of differentiation, which refers
  to groups of monoclonal antibodies that show
  similar reactivity with certain
  subpopulations?? of antigens of a particular
  lineage or differentiation stage. The
  subpopulations of antigens are also known by the
  same CD designation??.
• CD markers. Cell surface molecules of leucocytes
  and platelets??? that are distinguishable????
  with monoclonal antibodies and may be used to
  differentiate?? different cell populations.

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AM

• Adhesion molecules. Cell surface molecules
  involved in the binding of cells to extracellular
  matrix?? or to neighbouring cells, where the
  principal function is adhesion, rather than cell
  activation, e.g. integrins??? and
  selectins???.
• Cell adhesion molecules (CAMs). A group of
  proteins of the immunoglobulin supergene family
  involved in intercellular adhesion, including
  ICAM-1, ICAM-2, ICAM-3, VCAM-1, MAdCAM-1 and
  PECAM.
• Cell Adhesion Molecules Surface ligands??,
  usually glycoproteins, that mediate cell-to-cell
  adhesion??. Their functions include the
  assembly?? and interconnection of various
  vertebrate???? systems, as well as maintenance
  of tissue integration, wound healing, morphogenic
  movements, cellular migrations, and metastasis.

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B7

• B7-1 (CD80) and B7-2 (CD86). Two molecules which
  are present on antigen-presenting cells. They
  ligate?? CD28 on T cells and act as powerful
  co-stimulatory signals.

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CD2

• CD2 Antigens Glycoprotein??? members of the
  immunoglobulin superfamily which participate in
  T-cell adhesion?? and activation??. They are
  expressed on most peripheral T-lymphocytes,
  natural killer cells, and thymocytes????, and
  function as co-receptors or accessory??
  molecules in the T-cell receptor complex.

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FcR

• Fc receptors. Surface molecules on a variety of
  cells that bind to the Fc regions of
  immunoglobulins. They are antibody class specific
  and isotype ??? selective.
• Fc Receptors Molecules found on the surface of
  some, but not all, B-lymphocytes, T-lymphocytes,
  and macrophages, which recognize and combine with
  the Fc (crystallizable,???) portion of
  immunoglobulin molecules.

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MHC

• MHC (major histocompatibility complex). A genetic
  region found in all mammals???? whose products
  are primarily responsible for the rapid rejection
  of grafts??? between individuals, and function
  in signalling between lymphocytes and cells
  expressing antigen.
• MHC or Major Histocompatibility Complex The
  genetic region which contains the loci of genes
  which determine the structure of the
  serologically defined (SD) and lymphocyte-defined
  (LD) transplantation antigens, genes which
  control the structure of the immune
  response-associated antigens, the IMMUNE RESPONSE
  GENES which control the ability of an animal to
  respond immunologically to antigenic stimuli, and
  genes which determine the structure and/or level
  of the first four components of complement.

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HLA

• HLA The human major histocompatibility complex
• HLA Antigens Antigens determined by leukocyte
  loci found on chromosome 6, the major
  histocompatibility loci in humans. They are
  polypeptides?? or glycoproteins??? found on
  most nucleated cells and platelets, determine
  tissue types for transplantation, and are
  associated with certain diseases.

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HLA-I

• Histocompatibility Antigens Class I Large
  transmembrane??, polymorphic?? glycoproteins
  noncovalently??? associated with nonpolymorphic
  beta 2-microglobulin ????. In humans, three
  structural genes on chromosome 6 6???? code for
  the HLA-A HLA-B and HLA-C antigens. Class I
  antigens are found on most nucleated?? cells
  and are generally detected by their reactivity
  with alloantisera???????. These antigens are
  recognized during graft rejection and restrict
  cell-mediated lysis?? of virus-infected cells.
  They are primarily associated with
  rheumatologic?? diseases and certain malignant
  ??? disorders.

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HLA-II

• Histocompatibility Antigens Class II Large,
  transmembrane, non-covalently linked
  glycoproteins (alpha and beta). Both chains can
  be polymorphic although there is more structural
  variation?? in the beta chains. The class II
  antigens in humans are called HLA-D ANTIGENS and
  are coded by a gene on chromosome 6. The antigens
  are found on B-lymphocytes, macrophages,
  epidermal?? cells, and sperm?? and are
  thought to mediate the competence?? of and
  cellular cooperation in the immune response.

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Ir gene

• Ir gene. A group of immune response (Ir) genes
  determining the level of an immune response to a
  particular antigen or foreign stimulus. A number
  of them are found in the major histocompatibility
  complex.

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MHC-II

• MHC Class II Genes Genetic loci in the
  vertebrate major histocompatibility complex that
  encode polymorphic products which control the
  immune response to specific antigens. The genes
  are found in the HLA-D region in humans and in
  the I region in mice.

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ADCC

• ADCC (antibody-dependent cell-mediated
  cytotoxicity). A cytotoxic reaction in which Fc
  receptor- bearing killer cells recognize target
  cells via??,?? specific antibodies.
• ADCC The phenomenon of antibody-mediated target
  cell destruction?? by non-sensitized effector
  cells ????. The identity of the target cell
  varies, but it must possess surface IgG whose Fc
  portion is intact??. The effector cell is a
  "killer" cell possessing Fc receptors. It may be
  a lymphocyte lacking conventional ?? B- or
  T-cell markers??, or a monocyte, macrophage, or
  polynuclear??? leukocyte, depending on the
  identity of the target cell. The reaction is
  complement-independent.

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Antigen Receptors

• Antigen receptors. The lymphocyte receptors for
  antigens including the T-cell receptor (TCR) and
  surface immunoglobulin on B cells which acts as
  the B cell's antigen receptor (BCR).

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Antigen presentation

• Antigen presentation. The process by which
  certain cells in the body (antigen-presenting
  cells) express antigen on their cell surface in a
  form recognizable by lymphocytes.

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Antigen processing

• Antigen processing. The conversion?? of an
  antigen into a form in which it can be recognized
  by lymphocytes.

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APCs

• APCs (antigen-presenting cells). A variety of
  cell types which carry antigen in a form that can
  stimulate lymphocytes.
• Antigen-Presenting Cells Heterogeneous???
  group of immunocompetent ???? cells that
  mediates the cellular immune response by
  processing and presenting antigens to the T-cell
  receptor. Traditional antigen-presenting cells
  include MACROPHAGES DENDRITIC CELLS LANGERHANS
  CELLS and B-LYMPHOCYTES.

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BCR

• B-cell-co-receptor complex. A group of cell
  surface molecules consisting of complement
  receptor type 2 (CD21), CD81 and CD19, which act
  as a co-stimulatory receptor on mature B cells.  
• B-cell-receptor complex (BCR). B-cell surface
  immunoglobulin and its associated signalling
  molecules, CD79a and CD79b.

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CDRs

• CDRs (complementary-determining regions). The
  sections of an antibody or T-cell receptor V
  region responsible for antigen or antigen-MHC
  binding.
• CDR or Complementarity?? Determining Regions
  Three regions (CDR1, CDR2 and CDR3) of amino acid
  sequence in the Ig VARIABLE REGION ??? that are
  highly divergent ???. Together the CDRs from
  the light and heavy immunoglobulin chains form a
  surface that is complementary to the antigen.
  These regions are also present in other members
  of the immunoglobulin superfamily, for example,
  T-cell receptors.

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Tc

• Cytotoxic T cells. Cells which can kill virally
  infected targets expressing antigenic peptides
  presented by MHC class I molecules.

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DC

• Dendritic cells. A set of cells present in
  tissues, which capture antigens and migrate??
  to The lymph nodes and spleen, where they are
  particularly active in presenting The processed
  antigen to T cells. Dendritic cells can be
  derived from ?? either the lymphoid or
  mononuclear phagocyte lineages??.
• Dendritic Cells Immunocompetent cells of the
  lymphoid and hemopoietic?? systems and skin.
  They are also called interdigitating??,
  reticular??, and veiled?? cells. They
  function morphologically?? and
  phenotypically??? by processing antigens or
  presenting them to T-cells, thereby stimulating
  cellular immunity.

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TH

• Helper (TH) cells. A functional subclass?? of T
  cells which can help to generate cytotoxic T
  cells and cooperate with B cells in the
  production of antibody responses. Helper cells
  recognize antigen in association with class II
  MHC molecules.
• Helper-Inducer T-Lymphocytes Subpopulation of
  CD4 lymphocytes that cooperate with other
  lymphocytes (either T or B) to initiate a variety
  of immune functions. For example, helper-inducer
  T-cells cooperate with B-cells to produce
  antibodies to thymus-dependent antigens and with
  other subpopulations of T-cells to initiate?? a
  variety of cell-mediated immune functions.

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LAK

• Lymphokine activated killer cells (LAKs).
  Cytotoxic cells generated ex vivo??, by
  stimulation with IL-2, and possibly other
  cytokines.
• LAK cells (Lymphokine-Activated Killer Cells)
  Cytolytic lymphocytes with the unique capacity of
  killing natural killer (NK)-resistant fresh tumor
  cells. They are interleukin-2-activated NK cells
  that have no MHC restriction or need for antigen
  stimulation. LAK cells are used for adoptive
  immunotherapy in cancer patients.

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NK

• NK (natural killer) cells. A group of lymphocytes
  which have the intrinsic?? ability to recognize
  and destroy some vitally infected cells and some
  tumour cells.

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SC

• Stem Cells??? Relatively undifferentiated
  ??? cells that retain?? the ability to divide
  and proliferate?? throughout postnatal???
  life to provide progenitor?? cells that can
  differentiate into specialized cells.

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TC(R)

• T cells. Lymphocytes that differentiate primarily
  in the thymus?? and are central?? to the
  control and development of immune responses. The
  principal subgroups are cytotoxic T cells (Tc)
  and T-helper cells (TH0, TH1 and TH2).  
• T-cell receptor (TCR). The T-cell antigen
  receptor consisting of either an alpha beta
  dimmer ??? (TCR-2) or a gamma delta dimer
  (TCR-1) associated with the CD3 molecular complex.

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Immunity

• Immunity Nonsusceptibility to the invasive or
  pathogenic effects of foreign microorganisms or
  to the toxic effect of antigenic substances.

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Apopotosis

• Apoptosis??. Programmed cell death, which
  involves nuclear fragmentation ?? and
  condensation ?? of cytoplasm ???, plasma
  membranes and organelles ??? to apoptotic
  bodies ????.
• Apoptosis One of the two mechanisms by which
  CELL DEATH occurs (the other being the
  pathological process of NECROSIS ??). Apoptosis
  is the mechanism responsible for the
  physiological deletion of cells and appears to be
  intrinsically??? programmed. It is
  characterized by distinctive morphologic????
  changes in the nucleus and cytoplasm,
  chromatin??? cleavage ?? at regularly spaced
  sites, and the endonucleolytic cleavage of
  genomic DNA (DNA FRAGMENTATION) at
  internucleosomal sites. This mode of cell death
  serves as a balance to mitosis in regulating the
  size of animal tissues and in mediating
  pathologic processes associated with tumor
  growth.

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Class I/II restricition

• Class I/II restriction. The observation that
  immunologically active cells will only cooperate
  effectively when they share MHC haplotypes???
  at either the class I or class II loci.
• Genetic restriction. The term used to describe
  the observation that lymphocytes and
  antigen-presenting cells cooperate most
  effectively when they share particular MHC
  haplotypes???.
• MHC restriction. A characteristic of many immune
  reactions in which cells cooperate most
  effectively with other cells that share an MHC
  haplotype???,???.

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Co-stimulation

• Co-stimulation. The signals required for the
  activation of a lymphocyte, in addition to The
  antigen-specific signal delivered via their
  antigen receptors. CD28 is an important
  co-stimulatory molecule for T cells and CD40 for
  B cells.
•  

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Granzymes

• Granzymes???. Granule-associated enzymes of
  cytotoxic T cells and large granular lymphocytes.

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NF-kapaB

• NF-kapaB. A transcription?? factor which is
  widely used by different leukocyte populations to
  signal activation- sometimes called the
  master-switch??? of the immune system.

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Perforin

• Perforin ???. A granule-associated molecule of
  cytotoxic cells, homologous to complement C9. It
  can form pores on the membrane of a target cell.

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Primary response

• Primary response. The immune response (cellular
  or humoral) following an initial??
  encounter?? with a particular antigen.

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Secondary response

• Secondary response. The immune response which
  follows a second or subsequent?? encounter with
  a particular antigen.

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Immune Tolerance

• Immune Tolerance The specific failure of a
  normally responsive individual to make an immune
  response to a known antigen. It results from
  previous contact with the antigen by an
  immunologically immature individual (fetus or
  neonate) or by an adult exposed to extreme
  high-dose or low-dose antigen, or by exposure to
  radiation, antimetabolites, antilymphocytic
  serum, etc.
• Tolerance. A state?? of specific immunological
  unresponsiveness.

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Central tolerance

• Central tolerance ????. Tolerance of T cells or
  B cells induced during their development in the
  thymus or bone marrow ??.

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Clonal Deletion

• Clonal Deletion ??,?? Removal, via CELL DEATH,
  of immature??? lymphocytes that interact with
  antigens during maturation. For T-lymphocytes
  this occurs in the thymus and ensures that mature
  T-lymphocytes are self tolerant. B-lymphocytes
  may also undergo clonal deletion.

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Hypersensitivity

• Hypersensitivity. An inordinately?? strong
  immune response, which causes more damage than
  the antigen or pathogen ??? which induced the
  response.
• Hypersensitivity or allergy Altered reactivity
  to an antigen, which can result in pathologic
  reactions upon subsequent exposure to that
  particular antigen.

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Allergy

• Allergy????,???. Originally defined as altered
  reactivity on second contact with antigen now
  usually refers to a Type I hypersensitivity
  reaction.
• Hypersensitivity or allergy Altered reactivity
  to an antigen, which can result in pathologic
  reactions upon subsequent exposure to that
  particular antigen.

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Anaphylaxis

• Anaphylaxis???. An antigen-specific immune
  reaction mediated primarily by IgE which results
  in vasodilation???? and constriction?? of
  smooth muscle, including those of the
  bronchus???, and which may result in death.
• Anaphylaxis An acute hypersensitivity reaction
  due to exposure to a previously encountered
  antigen. The reaction may include rapidly
  progressing urticaria???, respiratory
  distress??, vascular collapse??, systemic
  shock, and death.

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Immediate Hypersensitivity

• Immediate?? Hypersensitivity Hypersensitivity
  reactions which occur within minutes of exposure
  to challenging??,?? antigen due to the release
  of histamine?? which follows the
  antigen-antibody reaction and causes smooth
  muscle contraction and increased vascular
  permeability?????.

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Cell Degranulation

• Cell Degranulation??? The process of losing
  secretory granules (SECRETORY VESICLES,?????).
  This occurs, for example, in mast cells ????,
  basophils??????, neutrophils??????,
  eosinophils??????, and platelets??? when
  secretory products are released from the granules
  by EXOCYTOSIS????.

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DTH

• DTH (delayed type hypersensitivity). This term
  includes the delayed skin reactions associated
  with Type IV hypersensitivity.

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Autoimmunity

• Autoimmunity. Immune recognition and reaction
  against the individual's own tissue.
• Autoimmunity Process whereby the immune system
  reacts against the body's own tissues.
  Autoimmunity may produce or be caused by
  AUTOIMMUNE DISEASES.

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Immune-complex

• Immune-complex. The product of an
  antigen-antibody reaction which may also contain
  components?? of the complement system.
• Antigen-Antibody Complex The complex formed by
  the binding of antigen and antibody molecules.
  The deposition?? of large antigen-antibody
  complexes leading to tissue damage causes IMMUNE
  COMPLEX DISEASES.

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Rheumatoid Factor

• Rheumatoid Factor ????? Antibodies directed
  against antigenic determinants, i.e., Gm (gamma
  chain), in the Fc region of Ig G, found in the
  serum of about 80 of patients with classical or
  definite rheumatoid arthritis, but in only about
  20 of patients with juvenile rheumatoid
  arthritis. Rheumatoid factors may be IgM, IgG, or
  IgA antibodies, although other serological tests
  measure only IgM. Rheumatoid factors also occur
  in other connective tissue diseases and
  infectious diseases.

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SLE

• SLE (systemic lupus erythematosus,???????). An
  autoimmune disease (non-organ specific) of humans
  usually involving anti-nuclear antibodies ????.
  
• SLE or Systemic Lupus Erythematosus A
  chronic??, relapsing???, inflammatory, and
  often febrile??? multisystemic disorder of
  connective tissue ????, characterized
  principally by involvement?? of the skin,
  joints, kidneys, and serosal membranes ??.

77
AIDS

• Acquired immune deficiency syndrome (AIDS). A
  progressive immune deficiency caused by infection
  of CD4 T cells with the human retrovirus?????
  HIV????????.
• Acquired Immunodeficiency Syndrome??????????
  An acquired defect of cellular immunity
  associated with infection by the human
  immunodeficiency virus (HIV), a CD4-positive
  T-lymphocyte count under 200 cells/microliter or
  less than 14 of total lymphocytes, and increased
  susceptibility??? to opportunistic infections
  and malignant neoplasms ????. Clinical
  manifestations also include emaciation
  (wasting,??) and dementia??,????.

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SCID

• SCID (severe combined immunodeficiency). A group
  of genetic conditions leading to major
  deficiencies or absence of both B cells and T
  cells.
• Severe Combined Immunodeficiency Group of rare
  congenital?? disorders characterized by
  impairment?? of both humoral?? and
  cell-mediated immunity, leukopenia??????, and
  low or absent antibody levels. It is
  inherited?? as an X-linked or autosomal????
  recessive?? defect.

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Tumor Antigens

• Tumor Antigens Generic term for both
  Tumor-Specific Antigens and Tumor-Associated
  Antigens.

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Tumor Specific Antigens

• Tumor Specific Antigens Antigens expressed
  exclusively by tumor cells. Few of them are
  identified because of the immune responses they
  induce are hardly detectable.

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Tumor-Associated Antigens

• Tumor-Associated Antigens Tumor non-specific
  antigens expressed by malignant tissue. They may
  also exist in normal cells and other tissues but
  markedly increase in cell canceration??. They
  are useful as tumor markers and are measured in
  the serum by means of a radioimmunoassay??????
  employing monoclonal antibodies. Fetal antigens
  such as alpha-fetoproteins (AFP) and
  carcinoembryonic antigen (CEA) are the typical
  representative members of this category.

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AFP

• alpha-Fetoproteins or AFP (????) The first
  alpha-globulins to appear in mammalian sera
  during development of the embryo ???? and the
  dominant???? serum proteins in early embryonic
  life. They reappear in the adult serum during
  certain pathologic states, primarily
  hepatocellular carcinoma.

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Adoptive Immunotherapy

• Adoptive?? Immunotherapy Form of adoptive
  transfer where cells with antitumor activity are
  transferred to the tumor-bearing host in order to
  mediate tumor regression??. The lymphoid cells
  commonly used are lymphokine-activated killer
  (LAK) cells and tumor-infiltrating??
  lymphocytes(TIL). This is usually considered a
  form of passive immunotherapy.

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Allograft

• Allograft ??????? or Homologous
  Transplantation Transplantation between
  individuals of the same species. Usually refers
  to genetically disparate???? individuals in
  contradistinction to ??? isogeneic
  ???,syngenic transplantation for genetically
  identical?? individuals.

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HVGR

• Host vs Graft Reaction (HVGR, ????????) The
  immune responses of a host to a graft. A specific
  response is GRAFT REJECTION.
• Graft Rejection An immune response with both
  cellular and humoral components, directed against
  an allogeneic???? transplant???, whose tissue
  antigens are not compatible with those of the
  recipient??.

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GVH

• GVH (graft versus host) disease.
• A condition caused by allogeneic donor ??
  lymphocytes reacting against host tissue in an
  immunologically compromised?? recipient.

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Histocompatibility

• Histocompatibility????? antigens The antigens
  primarily responsible for rejection of
  genetically different tissues are know as
  histocompatibility (i.e., tissue compatibility)
  antigen and the genes encoding these antigens are
  referred to as histocompatibility genes.
• ??????????????????????????????????????????????????

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Direct Recognition

• Direct Recognition ????Unique antigen
  recognition by T cells in transplantation.
  Conventional T-cell responses against foreign
  proteins require that such antigens are processed
  into peptides and presented on the surface of the
  recipient's APCs in association with MHC
  molecules. The transplant situation is unique in
  that foreign MHC molecules can directly activate
  T cells. Via their T-cell receptors (TCRs), the
  recipient's T cells involved in rejection
  recognize donor-derived peptides in association
  with the MHC antigens expressed on the graft.
• ??T???????????????????????????MHC?????
  ????APC????????????,???MHC????????T??????????T????
  ?TCRs??????????????????MHC???

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Indirect Recognition

• Indirect Recognition ????Normal physiological
  route??,manner?? of antigen recognition in
  transplantation. In this case, the recipient's
  APCs take in, process and present the deciduous
  departed, shedding ??? graft peptides in a form
  of self-MHCgraft peptide complex for the
  recognition of recipient's T cells.

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ELISA

• ELISA or Enzyme-Linked Immunosorbent Assay An
  sensitive immunoassay utilizing an antibody
  labeled?? with an enzyme? marker such as
  horseradish peroxidaseHRP,???????. While either
  the enzyme or the antibody is bound to an
  immunosorbent substrate??????, they both
  retain?? their biologic activity the change in
  enzyme activity as a result of the
  enzyme-antibody-antigen reaction is proportional
  to the concentration of the antigen and can be
  measured spectrophotometrically??? or with the
  naked eye. Many variations of the method have
  been developed.

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Immunoenzyme Techniques

• Immunoenzyme Techniques Immunologic techniques
  based on the use of (1) enzyme-antibody
  conjugates (2) enzyme-antigen conjugates (3)
  antienzyme antibody followed by its homologous
  enzyme or (4) enzyme-antienzyme complexes. These
  are used histologically for visualizing or
  labeling tissue specimens.

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Rosetting

• Rosetting????. A technique for identifying or
  isolating cells by mixing them with particles or
  cells to which they bind (e.g. sheep erythrocytes
  to human T cells). The rosettes consist of a
  central cell surrounded by bound cells.

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Vaccination

• Vaccination????. A general term for
  immunization against infectious disease,
  originally derived from immunization against
  smallpox?? which uses the Vaccinia virus????.

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Western blotting

• Western blottingSynonymous?? with
  immunoblotting
• Western Blotting Identification of proteins or
  peptides that have been electrophoretically??
  separated by blot transferring from the
  electrophoresis gel???? to strips of
  nitrocellulose????? paper, followed by labeling
  with antibody probes??.
• Immunoblotting???? Immunologic method used for
  detecting or quantifying?? immunoreactive
  substances. The substance is identified?? by
  first immobilizing it by blotting onto a membrane
  and then tagging?? it with labeled antibodies.

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Thank you !