[Rheologic and biophysical aspects of cellular adhesion and aggregation: importance in hemorheology].
Interactions between blood cells in the form of cellular aggregates or adhesion are observed in a variety of normal and pathological conditions. Aggregation of erythrocytes or platelets, adhesion of platelets and leucocytes and immune agglutination of RBC are examples of interactions involving blood cells. Cell adhesion and aggregation are modulated by specific interactions (antigen-antibodies reactions, adhesive macromolecules interactions...) or non-specific (van der Waals forces, electrostatic interactions, molecular bridgings...). These interactions may result in morphological and structural changes, or polarization phenomena. At the dynamic level, cellular adhesion (or aggregation) can divided in 4 main steps: transport, cellular activation (endogenous or exogenous), morphological, physical or steric rearrangements, contact (intercellular or on an artificial surfaces). It will be the nature of the interactions involved in these steps that will determine the binding cohesion and kinetic. In this paper, different types of interactions and the regulation mechanisms of adhesion and aggregation phenomena involved in blood hemodynamics will be summarized and some examples (RBC or platelets aggregation; platelets or leucocytes adhesion) will illustrate the importance of these phenomena in clinical hemorheology.
Stoltz
J F
JF
U 424 INSERM, Faculté Odontologie, Strasbourg.
Senger
B
B
Voegel
J C
JC
Delamaire
M
M
Schaaf
P
P
Boisseau
M
M
D055592:Biophysical Phenomena; D001703:Biophysics; D001773:Blood Cells / Q000166:cytology*; D002448:Cell Adhesion / Q000502:physiology; D002449:Cell Aggregation / Q000502:physiology; D004903:Erythrocyte Aggregation / Q000502:physiology; D018056:Hemorheology; D006801:Humans; D010974:Platelet Aggregation / Q000502:physiology; D013601:T-Lymphocytes / Q000166:cytology