20.109(F11): MLD

WF Team Pink/Purple

• Michelle Fung
• Luis Juarez
• Dorma Flemister

Project Overview

• Fibrin and its uses as scaffold in tissue engineering and gene delivery.
• Curing a Heart Disease through the use of Fibrin scaffolds.

Background Information

Title: Strategies for Tissue Engineering Cardiac Constructs to Affect Functional Repair Following Myocardial Infarction Ye, K. Y., & Black, L. D.,3rd. (2011). Strategies for tissue engineering cardiac constructs to affect functional repair following myocardial infarction. Journal of Cardiovascular Translational Research, 4(5), 575-591.

• http://www.springerlink.com/content/k028661713380485/fulltext.html

Fibrin is an attractive alternative biopolymer for cardiac tissue engineering because:

• it can be easily formed into fibrillar networks, similar to type I collagen
• it can be autologous, since fibrin can be extracted from the patient’s blood, which reduces the chances of the body rejecting the scaffold as a foreign object
• fibrin gel is very bioactive, stimulating the cells
• it has been FDA-approved as a surgical sealant

Title: Fibrin gel – advantages of a new scaffold in cardiovascular tissue engineering

• http://ejcts.ctsnetjournals.org/cgi/content/abstract/19/4/424

The field of tissue engineering deals with the creation of tissue structures based on patient cells. The scaffold plays a central role in the creation of 3-D structures in cardiovascular tissue engineering like small vessels or heart valve prosthesis. An ideal scaffold should have tissue-like mechanical properties and a complete immunologic integrity. As an alternative scaffold the use of fibrin gel was investigated.

• Yuan Ye, K., Sullivan, K. E., & Black, L. D. (2011). Encapsulation of cardiomyocytes in a fibrin hydrogel for cardiac tissue engineering. Journal of Visualized Experiments : JoVE, (55). pii: 3251. doi(55), 10.3791/3251.

Cardiomyocytes were cultured in a three dimensional hydrogel and studied Fibrin is a naturally occurring blood clotting protein. The paper describes the isolation of neonatal cardiomyocytes form three day old rat pups and their preparation for encapsulation in the fibrin gel constructs. Immunohistological staining was performed to examine the expression and morphology of some essential proteins.

• Barsotti, M. C., Felice, F., Balbarini, A., & Di Stefano, R. (2011). Fibrin as a scaffold for cardiac tissue engineering. Biotechnology and Applied Biochemistry, 58(5), 301-310.

http://www.ncbi.nlm.nih.gov/pubmed?term=Barsotti%2C%20M.%20C.%2C%20Felice%2C%20F.%2C%20Balbarini%2C%20A.%2C%20%26%20Di%20Stefano%2C%20R.%20(2011).%20Fibrin%20as%20a%20scaffold%20for%20cardiac%20tissue%20engineering.%20Biotechnology%20and%20Applied%20Biochemistry%2C%2058(5)%2C%20301-310

This review shows some cardiac bioengineering uses of fibrin as a cell delivery vehicle and as an implantable biomaterial. Fibrin is great to be used since it is a natural biopolymer that has properties like biocompatibility, ease of processing, and a potential for incorporation of cells and cell mediators. Fibrin has found many applications in tissue engineering because it can be combined with cells, growth factors, or drugs.

Tissue Engineering Strategies for Cardiac Regeneration

• Amandine F. G. Godier-Furnémont, Yi Duan, Robert Maidhof and Gordana Vunjak-Novakovic
• http://www.springerlink.com/content/t60q875248r8w377/fulltext.html

"Functional vascularization – with the establishment of blood supply – remains a major unsolved problem of cardiac tissue engineering, and tissue engineering in general. Several different approaches are currently under investigation, ranging from the engineering of prevascularized tissues with capability for connection to the blood supply of the host, to the induction of vascularization by host cells using bioactive materials"

Title: Fibrin: A Versatile Scaffold for Tissue Engineering Applications

• TAMER A.E. AHMED, M.Sc., EMMA V. DARE, B.Sc., and MAX HINCKE, Ph.D.
• http://www.liebertonline.com/doi/abs/10.1089/ten.teb.2007.0435

"Fibrin as an ideal scaffold has a significant disadvantage: the gradual disintegration of the gel with subsequent loss of shape and volume before the proper formation of tissue-engineered constructs. This disadvantage can be overcome by optimizing the concentrations of fibrinogen, calcium ion (Ca2þ), and pH, by using a lower cell density or by adding specific protease inhibitors. Stability can also be enhanced by using highly denatured densely cross-linked FMBs or by combining fibrin with an artificial supporting polymer. Fibrin gel shrinkage and its low mechanical stiffness represent other disadvantages of fibrin scaffolds in some tissue engineering applications, which can be controlled by cross-linking or by combining fibrin with other artificial scaffolding material."

Tissue response to poly(ether)urethane-polydimethylsiloxane-fibrin composite scaffolds for controlled delivery of pro-angiogenic growth factors

• Paola Losia, Enrica Brigantia, Angela Magerab, Dario Spillera, Chiara Ristorib, Barbara Battollab, Michela Balderia, Silvia Kulla, Alberto Balbarinib, Rossella Di Stefanob, Giorgio Soldani
• http://www.sciencedirect.com/science/article/pii/S0142961210003893

"IHA of subcutaneously implanted samples showed that at 7 and 14 days the PEtU–PDMS/Fibrin + GFs scaffold induced a statistically significant increase in number of capillaries compared to bare PEtU–PDMS scaffold. IHA of ischemic hind limb showed that at 14 days the capillary number induced by PEtU–PDMS/Fibrin + GFs scaffolds was higher than that of PEtU–PDMS/Fibrin scaffolds. Moreover, at both time-points PEtU–PDMS/Fibrin scaffolds induced a significant increase in number of capillaries compared to bare PEtU–PDMS scaffolds."

Composite scaffold provides a cell delivery platform for cardiovascular repair

• http://www.pnas.org/content/early/2011/04/19/1104619108.full.pdf

Composite scaffold provides a cell delivery platform for cardiovascular repair

• http://onlinelibrary.wiley.com/doi/10.1002/jbm.b.31146/pdf

Research Ideas on Problem and Goals

• Identify a currently unsolved problem for fibrin as scaffold for use to treat cardiac disease and try to fix it.
• Fibrin gels are ideal for use as a scaffold but they have two disadvantages. They shrink in size due to fibrin degradation and initially have low mechanical stiffness which do not allow for direct implantation of the new formed structures.
  • It is possible to use a combination of high porous biodegradable scaffolds with the fibrin gel as a cell carrier.
• Composite/hybrid scaffold of fibrin + synthetic (or other) material?
  • Chitosan?
  • Polyurethane?

[LAJ/02 December 2011].

These four papers have a great idea. Let's explore and adjust to fit our needs. Please read one or more of these papers and post a summary as it relates to what we want to do.

I found a great paragraph explaining the use of Chitosan as the scaffold and Fibrin as a kind of glue to attach the heart cells to the scaffold. Assays at 3 weeks were: 1) survival, 2) vascularization, 3) organization, 4) functionality, 5) stability, 6) precondition to modulate contractile properties of transplanted myocardial cells.

EHT is Engineered Heart Tissue (a patch of cells). This is the paragraph I found in "Fibrin as a scaffold for cardiac tissue engineering."

"An EHT was also obtained with a miniaturized and automated method, by mixing neonatal rat heart cells, fibrin, and Matrigel [14]. This method may provide advanced in vitro models for drug testing and disease modeling. Cardiac tissue has also been successfully engineered using cardiac myocytes both in vitro and in vivo [47]. Engineering 3D cardiac tissue is usually limited by the difficulty of nourishment supply to cells in the center of the construct. In these articles, an intrinsic vascular supply was incorporated in a contractile 3D cardiac tissue, using a suspension of neonatal cardiac myocytes in fibrin gel. The suspension was used to cellularize porous scaffolds made of chitosan and opportunely molded. Fibrin gel was required to retain the cells within the constructs and resulted in the formation of contractile constructs. At 3 weeks, survival, vascularization, organization, and functionality of transplanted myocardial cells was demonstrated. The same authors further developed the engineering of this 3D heart muscle, demonstrating its stability in response to stretch protocols and engineering a functional cellbased cardiac pressure-generating construct [85]. The bioengineered heart muscle containing fibrin was also preconditioned, modulating its contractile properties for possible implantation onto injured hearts without cell shock [86]."

Paper 1: http://www.ncbi.nlm.nih.gov/pubmed?term=hansen%2C%20A.%2C%20Eder%2C%20A.%2C%20Bonstrup%2C%20M.%2C%20Flato%2C%20M.%2C%20Mewe%2C%20M.%2C

Paper 2:

Paper 3:

Paper 4:

Project Details and Methods

• Immunofluorescence

Predicted Outcomes

• If all goes well, we’ll have increased efficacy in Cardiac Cell Therapy
• If nothing goes well, we’ll end up knowing more potential uses of Fibrin, and more of its properties for use in Tissue Engineering.

Necessary Resources

• $$
• Cells, materials, knowledge of assays
• Eventually animal trials (Heart Surgeons)
• Eventually Human trials (more $)