Experimental Study of Fibrin/Fibrin-Specific Molecular Interactions Using a Sphere/Plane Adhesion Model

Abstract

Fibrin, the biopolymer produced in the final step of the coagulation cascade, is involved in the resistance of arterial thrombi to fragmentation under shear flow. However, the nature and strength of specific interactions between fibrin monomers are unknown. Thus, the shear-induced detachment of spherical monodispersed fibrin-coated latex particles in adhesive contact with a plane fibrin-coated glass surface has been experimentally studied, using an especially designed shear stress flow chamber. A complete series of experiments for measuring the shear stress necessary to release individual particles under various conditions (various number of fibrin layers involved in the adhesive contact, absence or presence of plasmin, the main physiological fibrinolytic enzyme) has been performed. The nonspecific DLVO interactions have been shown to be negligible compared to the interactions between fibrin monomers. A simple adhesion model based on the balance of forces and torque on particles, assuming an elastic behavior of the fibrin polymer bonds, to analyze the experimental data in terms of elastic force at rupture of an elementary intermonomeric fibrin bond has been used. The results suggested that this force (of order 400 pN) is an intrinsic quantity, independent of the number of fibrin layers involved in the adhesive contact. Copyright 2001 Academic Press.

Polymerization of fibrin: specificity, strength, and stability of knob-hole interactions studied at the single-molecule level

“…39 Because a fibrin molecule is bivalent and has an A-knob and an a-hole reacting in each of 2 interacting partners (Figure 1), the measured binding strength may be doubled to 250 to 260 pN for bimolecular fibrin-fibrin interactions. To our knowledge, the only work attempting to quantify the singlemolecule fibrin monomer-monomer binding strength reported a value on the order of 400 pN, 40 which was calculated indirectly from the parameters of shear-induced detachment of fibrin-coated beads from the fibrin-coated surfaces. Although this value has the same order of magnitude, it may not be comparable because rupture forces are dependent on the loading rate, which was not reported in this earlier study.…”

Measuring the force of adhesion between multiple kinesins and a microtubule using the fluid force produced by microfluidic flow

“…However, we could not use this equation because of the strong wall effect caused by the underlying glass surface. The drag force acting on micro/nano scale objects adjacent to a solid surface and subjected to a shearing flow has been examined both experimentally and theoretically (Lorthois et al 2001). …”

“…The lengths of the kinesins that link the microtubules to the beads are expressed by percentage of the extended kinesin length (see Results and Discussion for details). The adhesion force, F Adh , and the torque, C Adh , associated with the kinesin springs are expressed as: (Lorthois et al 2001)…”

“…The adhesion force between a kinesin/bead and a microtubule was calculated using a mechanical model that included the fluid force, which is the flow rate required to release the kinesin/ bead from the microtubule. Such a model was initially used by Lorthois et al for a system that incorporated beads bound to a stainless surface by fibrin fibers (Lorthois et al 2001), although they used the shear stress on the glass surface to calculate the adhesion force. Therefore, we derived the adhesion force directly from the fluid drag force and the torque, and accounted for the distance between the bead and the underlying microtubules.…”

Determination of the Shear Force at the Balance between Bacterial Attachment and Detachment in Weak-Adherence Systems, Using a Flow Displacement Chamber

“…In order to characterize the attachment and detachment of bacteria with respect to wall shear, notions such as "shear to prevent adhesion" and "shear to remove adhered bacteria" are used (1,3,5,6,9,10). Shear stresses in the range of 12 to 54 Pa have been reported to be necessary for the removal of different bacterial strains from regular surfaces, and usually a lower shear stress is required to prevent adhesion (17).…”