Comparative characteristics of integrin αDβ2 binding to native fibrinogen and fibrinogen modified by DHA oxidation during inflammation
Location
Culp Center Rm. 304
Start Date
4-25-2023 9:40 AM
End Date
4-25-2023 10:00 AM
Faculty Sponsor’s Department
Biomedical Sciences
Name of Project's Faculty Sponsor
Valentin Yakubenko
Competition Type
Competitive
Type
Oral Presentation
Project's Category
Molecular Biology, Cell Biology, Membrane Transport
Abstract or Artist's Statement
2-ω-carboxyethylpyrrole (CEP) is a product of Docosahexaenoic acid (DHA) oxidation, which forms covalent adducts with different proteins. CEP-modified proteins can interact with macrophage receptor, integrin αDβ2. This study aims to compare αDβ2 binding to its physiological ligand, fibrinogen, and CEP-modified fibrinogen, which is formed during inflammation. We hypothesize that modification of fibrinogen changes its ligand-binding properties to integrin αDβ2 which can affect macrophage migration and retention.
Recombinant αD I-domain and αDβ2-transfected HEK293 cells were used for the experiments. In biolayer interferometry (BLI) assays, fibrinogen was immobilized at pH 5.0 and fibrinogen-CEP at pH 3.5. Our results showed that the affinity of αD I-domain binding to fibrinogen-CEP was higher than fibrinogen, and the binding was inhibited by the anti-CEP antibody. The optimal expression of αD I-domain was found at 25°C.
In cell adhesion assays, optimal concentrations were used for the inhibition assay; fibrinogen at 2µg/ml and fibrinogen-CEP at 8µg/ml. αDβ2-transfected cells demonstrated stronger adhesion to fibrinogen-CEP, and this adhesion was significantly inhibited by polyglutamic acid, which mimics CEP-mediated binding.
These findings suggest that αDβ2's interaction with DHA-modified extracellular matrix (ECM) proteins significantly increases macrophage adhesion and may serve for macrophage retention during chronic inflammation. Developing small molecules that can inhibit αDβ2-CEP interaction could be a breakthrough in treating inflammatory diseases.
The main conclusions drawn from the study are that CEP-modified fibrinogen has a higher affinity for αD I-domain binding than native fibrinogen, and this interaction can be inhibited by targeting CEP. The study provides insights into the potential therapeutic applications of inhibiting αDβ2-CEP interactions in inflammatory diseases.
Comparative characteristics of integrin αDβ2 binding to native fibrinogen and fibrinogen modified by DHA oxidation during inflammation
Culp Center Rm. 304
2-ω-carboxyethylpyrrole (CEP) is a product of Docosahexaenoic acid (DHA) oxidation, which forms covalent adducts with different proteins. CEP-modified proteins can interact with macrophage receptor, integrin αDβ2. This study aims to compare αDβ2 binding to its physiological ligand, fibrinogen, and CEP-modified fibrinogen, which is formed during inflammation. We hypothesize that modification of fibrinogen changes its ligand-binding properties to integrin αDβ2 which can affect macrophage migration and retention.
Recombinant αD I-domain and αDβ2-transfected HEK293 cells were used for the experiments. In biolayer interferometry (BLI) assays, fibrinogen was immobilized at pH 5.0 and fibrinogen-CEP at pH 3.5. Our results showed that the affinity of αD I-domain binding to fibrinogen-CEP was higher than fibrinogen, and the binding was inhibited by the anti-CEP antibody. The optimal expression of αD I-domain was found at 25°C.
In cell adhesion assays, optimal concentrations were used for the inhibition assay; fibrinogen at 2µg/ml and fibrinogen-CEP at 8µg/ml. αDβ2-transfected cells demonstrated stronger adhesion to fibrinogen-CEP, and this adhesion was significantly inhibited by polyglutamic acid, which mimics CEP-mediated binding.
These findings suggest that αDβ2's interaction with DHA-modified extracellular matrix (ECM) proteins significantly increases macrophage adhesion and may serve for macrophage retention during chronic inflammation. Developing small molecules that can inhibit αDβ2-CEP interaction could be a breakthrough in treating inflammatory diseases.
The main conclusions drawn from the study are that CEP-modified fibrinogen has a higher affinity for αD I-domain binding than native fibrinogen, and this interaction can be inhibited by targeting CEP. The study provides insights into the potential therapeutic applications of inhibiting αDβ2-CEP interactions in inflammatory diseases.