A Microfluidic Approach for Investigating Thrombosis and Hemostasis / Yue Liu.

Format:

Book

Thesis/Dissertation

Author/Creator:

Liu, Yue, author.

Contributor:

University of Pennsylvania. Chemical and Biomolecular Engineering, degree granting institution.

Language:

English

Subjects (All):

Molecular biology.

Biochemistry.

Bioengineering.

Chemical and Biomolecular Engineering--Penn dissertations.

Penn dissertations--Chemical and Biomolecular Engineering.

Local Subjects:

Molecular biology.

Biochemistry.

Bioengineering.

Chemical and Biomolecular Engineering--Penn dissertations.

Penn dissertations--Chemical and Biomolecular Engineering.

Physical Description:

1 online resource (71 pages)

Contained In:

Dissertations Abstracts International 85-03B.

Place of Publication:

[Philadelphia, Pennsylvania] : University of Pennsylvania, 2022.

Ann Arbor : ProQuest Dissertations & Theses, 2023

Language Note:

English

Summary:

Previously, studies on cardiovascular biology in vitro were predominantly conducted using static assays with plasma or isolated blood cells. However, microfluidic technologies present a distinctive opportunity to investigate the mechanisms of hemostasis and thrombosis in conditions that mimic physiological settings. This thesis outlines the utilization of a microfluidic method to simulate cardiovascular ailments and assess potential treatments. In our studies, platelet deposition on collagen was measured using thrombin-inhibited anticoagulated treated whole blood with various TLR agonists. It was observed that most of the tested TLR agonists reduced platelet deposition, except for TLR4 agonist LPS which increased deposition. TLR-7 agonists caused an immediate blockade of platelet deposition. Inhibitors of the IKK/NF-ΚB pathway also strongly inhibited platelet deposition under flow. Addition of Pam3CSK4 (TLR1/2 ligand), MALP-2 (TLR2/6 ligand) and Imquimod (TLR7 ligand) reduced phosphotidylserine (PS) exposure. Activation of TLR1/2, TLR2/6, TLR3, TLR7, TLR9 in whole blood reduced platelet deposition under flow on collagen, however LPS activation of TLR4 was clearly pro-thrombotic. We also used our microfluidic clotting assays to monitor Factor XIIIa activity and fibrin in whole blood clots forming under flow. We tested a fluorescent peptide derived from alpha-2 antiplasmin sequence to monitor the location of transglutaminase activity and fibrin during whole blood clotting under microfluidic flow. The peptide rapidly appeared in the same location as accumulating fibrin, as expected for a transglutaminase activity bound to fibrin. The thrombin inhibitor PPACK ablated fibrin generation and concomitant peptide labeling of fibrin. The FXIIIa inhibitor T101 had no effect on fibrin generation but ablated the labeling of fibrin by the peptide. Similarly, Gly-Pro-Arg-Pro abated fibrin formation and thus strongly attenuated the peptide signal. At arterial wall shear rate, less fibrin was formed and consequently less peptide labeling of fibrin was detected as compared to venous conditions. Addition of tissue plasminogen activator caused a reduction of both fibrin and peptide signal. Also, the peptide strongly colocalized with fibrin in clots from laser-injured mouse cremaster arterioles. The synthetic peptide provided a strong and sustained labeling of fibrin as it formed under flow.

Notes:

Source: Dissertations Abstracts International, Volume: 85-03, Section: B.

Advisors: Diamond, Scott L.; Committee members: Brass, Lawrence F.; Sinno, Talid R.; Lim, Bomyi.

Department: Chemical and Biomolecular Engineering.

Ph.D. University of Pennsylvania 2023.

Local Notes:

School code: 0175

ISBN:

9798380388528

Access Restriction:

Restricted for use by site license.

This item is not available from ProQuest Dissertations & Theses.