Peptide targeted imaging of neutrophil invasion in cardiac tissue

Melhem, Molly

Permalink

https://hdl.handle.net/2142/44227 Copy

Description

Title

Peptide targeted imaging of neutrophil invasion in cardiac tissue

Author(s)

Melhem, Molly

Issue Date

2013-05-24T21:54:49Z

Director of Research (if dissertation) or Advisor (if thesis)

Schook, Lawrence B.

Department of Study

Bioengineering

Discipline

Bioengineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

M.S.

Degree Level

Thesis

Keyword(s)

• Peptide targeting
• reperfusion
• neutrophil blocking

Abstract

The goal of this project is to engineer a benchtop model to test the efficacy of neutrophil blocking peptides, and provide a foundation for in vivo studies of peptide blocking. Current medical practices address the initial occlusion of heart flow by a surgical technique that re-opens the affected artery. If done early enough, this intervention can save what would otherwise be necrotic tissue; however, if sufficient time has elapsed, the reintroduction of blood flow to a now hypoxic environment may further harm otherwise healthy tissue. When deprived of oxygen for an extended period of time, the environment of the occluded vessel is primed for neutrophil invasion that results in damage to the surrounding tissue. The introduction of blocking peptides that interrupt the neutrophil-endothelial cell interactions are promising as a therapy for decreasing the damage following reperfusion. Through disruption of neutrophil invasion, the tissue damage mediated by ICAM-1 and VCAM-1 endothelial cell membrane proteins can be minimized. In this project, we paired ICAM-1 and VCAM-1 blocking peptides with fluorophores to allow for physical and quantitative analysis of peptide binding. To test the specific efficacy of the peptide on endothelial cell proteins, we created ICAM-1 and VCAM-1 expressing cell lines to use as an in vitro test platform for both peptide and neutrophil binding. In future studies, our test platform will be paired with fluorescent microscopy and microfluidic flow chambers to test the binding efficiency of the peptide blockers and inhibition of neutrophil interactions. By doing so we have created an in vitro model to visualize the physical binding properties of peptide blockers and assess the impact of competitive binding on neutrophil interaction. In addition, we developed a myocardial infarction and reperfusion model to pair visualization of peptide bonding with functional studies that test the beneficial effect. In this way we can correlate the amount of neutrophil blocking necessary to significantly improve heart function following the reperfusion treatment that accompanies myocardial infarctions. Anticipated outcomes of this project were to engineer an in vitro testing platform to monitor neutrophil infiltration blocking, and to establish an in vivo model to analyze targeting peptides and their therapeutic outcomes. This was done through the utilization of peptides that target inflammation associated with cardiac disease, the pairing of said peptides with fluorophores that enable us to visualize the peptide interaction, and the use of microfluidic chambers to observe and quantify neutrophil binding and infiltration.

Graduation Semester

2013-05

Permalink

http://hdl.handle.net/2142/44227

Copyright and License Information

Copyright 2013 Molly Melhem

Owning Collections