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chapter 35
Molecular Immunology
T A B L E
3 5 - 1
Components of the Immune System (continued)
Protein Components
Principal Functions
Structural Characteristics
Related
Figure(s) or
Tables
Immunoglobulins
Ig’s confer humoral immunity,
Four chains, two heavy and two
Figure 7
react with epitopes on antigens
light chains, charateristic fold
Table 35-2
Cytokines
when bound to antigens initiate
complement activation
Proteins that can communicate
between /3-sheet domains,
“immunoglobulin” fold
Table 35-4
CD3 Complex
with and stimulate immune and
other cells to proliferate,
synthesize specific proteins
T-cell surface glycoprotein
Heterodimer of either:
all3
or
CD3D(delta)
found on all T-cells
Sly
chains
CD3E(epsilon)
CD3G(gamma)
CD3H(eta)
CD3Z(zeta)
CD4
Forms a complex with TcR
Mediates signal transduction
across the cell membrane
T-cell surface glycoprotein,
Structure:
Figure 4
Interacts with
IL-16,
corecep-
tor with
TcR
in recognizing
Single polypeptide chain,
3 domains,
Figure 16
MHC Class II
presented
1) extracellular, (-370 res);
Figure 17
CD
8
peptides, identifier of
T-helper cells
T-cell surface glycoprotein,
2) transmembrane, (-25 res)
3) intracellular (-38 res)
Heterodimer of
a/fi
chains, can
Figure 3
Interleukins
Interacts with
MHC Class I
Identifier of cytotoxic or
suppressor T-cells
See Table 35-4
form homodimers
Table 35-4
Perforin
B cell receptors
Permeability induction for
ADCC cell destruction
Specific to individual antigen
IgM molecules anchored to
Figure 1
(epitope)
B-cell membrane
Table 35-2
T cell receptors (TcR)
T-cell surface glycoprotein,
Structure: 2 o:/3-polypeptide
Figures 1 and 3
(Many copies of each
with CD4 or CD
8
binds to
chains with immunoglobulin
Figure 14
TcR
on each cell, all
MHC proteins on surface of
folds; VaCa and V^C^
directed for the same
antigen presenting cells
OR 2
Sy
polypeptide chains
epitope (antigen))
(less prevalent form)
(c o n tin u e d )
