Adhesion Molecules Concept Naming Roles Classification Slide 2
Concept Cell adhesion molecules (CAMs): proteins which exist in
cell surface involve in the binding of cells to each other or to
extracellular matrix. Exist as couples( receptor-ligand) Co-effect
with many couples Slide 3 Slide 4 TCR complex, Co receptor,
Co-stimulator receptor, immunological synapse Slide 5 Interactions
between B cell and Th cell B cell activation B cell Th cell Ag
processing Th cell activation Slide 6 Naming Functions ICAM-1
(intercellular adhesion molecules), LFA-1 (lymphocyte function
associated antigen-1) VCAM (vascular cell adhesion molecules),
PECAM1(platelet-endothelial-cell adhesion molecule), CD CD58, CD152
Slide 7 Leukocyte differentiation antigen: Cell surface molecules
expressed (or disappeared) on different developmental and
differential phases of blood cells. CD: cluster of differentiation
(uses of McAb) CD molecules: The same differentiation antigen
recognized by different monoclone antibodies from different labs is
called CD molecule. Naming by method of identification CD molecules
have a variety of functions Slide 8 Classification Most of the CAMs
can be grouped by structure into five families: Immunoglobulin (Ig)
superfamily Integrin family Selectin family Cadherin family
Mucin-like family Others Slide 9 Ig superfamily CAMs The structure
of these adhesion molecules resemble that of Ig. Members of the Ig
superfamily include the intercellular adhesion molecules (ICAMs),
vascular cell adhesion molecule (VCAM-1), platelet-endothelial-cell
adhesion molecule (PECAM-1), and neural cell adhesion molecule
(NCAM). Slide 10 Slide 11 Back Slide 12 Integrins Integrins consist
of alpha(1-16) and beta(1 - 8) chains VLA-4 (very late antigen-4) 4
1 ------VCAM-1, LFA-1 1 2 -----ICAM-1, ICAM-2, ICAM-3 Slide 13
LFA-1 lymphocyte function associated antigen-1) thymocyte, T cell,
macrophage ICAM-1 2 3 APC Slide 14 Selectins The molecule consists
of one peptide chain which has carbohydrate-binding domain. Bing to
Sialyl-Lewis (sialyl Louis) oligosaccharides three family members:
endothelial (E)-selectin, leukocyte (L)-selectin, and platelet
(P)-selectin. Slide 15 Roles functions of cell adhesion molecules
To mediate the contact and adhesion between cell and cell, or
between cell and extracellular matrix resulting to various biologic
effects. Cell surface adhesion molecules play vital roles in
numerous cellular processes. 1 Involvement in lymphocyte formation
and differentiation 2 Involvement in immune response and immune
regulation 3 Involvement in inflammation 4 Involvement in
lymphocyte homing 5 Involvement in regulation of apoptosis Slide 16
1 Involvement in lymphocyte formation and differentiation Thymocyte
Epithelial cell CD2---------------IFA-3 IFA-1-------------- ICAM-1
Slide 17 2 Involvement in immune response and immune regulation
Take part in recognition of immnocytes Slide 18 3 Involvement in
inflammation mediate the adhesion of leukocytes with endothelial
cells during inflammation. Slide 19 Transendothelial migration of
leukocytes Transendothelial migration demonstrates cooperativity
between leukocyte and endothelial cell adhesion molecules. Slide 20
(1) rolling, Initial rolling is mediated by binding of E-selectin
molecules on the vascular endothelium to sialylated carbohydrate
moieties on mucinlike CAMs. (2) activation by chemoattractant
stimulus, A chemokine such as IL-8 then binds to its receptor on
the neutrophil, triggering an activating signal. This signal
induces a conformational change in the integrin molecules, enabling
them to adhere firmly to Ig- superfamily molecules on the
endothelium (3) arrest and adhesion, The interaction between
integrins and Ig-superfamily CAMs stabilizes adhesion of the
neutrophil to the endothelial cell, enabling the cell to adhere
firmly to the endothelial cell. (4) transendothelial migration
Transmigration of the leukocyte through adjacent endothelial cells
in a process called diapedesis. PECAM-1 is a crucial player in this
step. This step is largely unknown.. Slide 21 Slide 22 Slide 23 4
Involvement in lymphocyte homing take part in lymphocyte homing and
recirculation Homing receptor on lymphocyte: L-selectin, LFA-1,
vascular addressin on HEVs: GlyCAM-1(glycosylation dependent cell
adhesion molecules), CD34; ICAM-1 L-selectin ----- GlyCAM-1, CD34
LFA-1 ----- ICAM-1 Slide 24 Slide 25 HEV are specialized venules
found in lymphoid tissues. Lymphocytes migrate from blood into
lymphoid tissues by attaching to and migrating across the high
endothelial cells of the vessels. High endothelial venule HEV Slide
26 Clinical application of CD and adhesion molecules Elucidating
pathological mechanism of disease Application during diagonosis of
disease Application during prevention and treatment of disease
