Details

Autor(en) / Beteiligte

• Dreger, Sally Anne

Titel

Matrix remodelling: a requirement for heart valve tissue engineering

Ort / Verlag

ProQuest Dissertations & Theses

Erscheinungsjahr

2008

Quelle

ProQuest Dissertations & Theses A&I

Beschreibungen/Notizen

• This thesis has begun to address the developmental stages of a tissue engineered heart valve construct by observing and demonstrating the properties required to not only anatomically and histologically resemble the native valve but also to attain the cellular milieu and function as the native valve. In the first set of studies, the profile of matrix metalloproteinases (MMPs) and their inhibitors, the tissue inhibitors of metalloproteinases (TIMPS) was assessed in all four â normalâ native valve leaflets (aortic, valve, pulmonary valve, mitral valve and tricuspid valve). This profile was compared with the MMP profile observed in diseased valve leaflets. Extrapolating this data, valve ICs were then seeded onto a biological scaffold (bovine type I collagen) to assess their matrix remodelling potential by looking at the matrix metalloproteinases (collagenases, gelatinase, stromolysin-1 and membrane-type 1 MMP) and the expression of collagen I, III and elastin mRNA. These results provided the basis to test the mechanical properties of seeded scaffolds and compare them with those of the native valve. Although the stiffness (Youngâ Modulus) and the fracture point (ultimate tensile strength) of the seeded scaffolds were less than native valve leaflets, the strain to failure (elasticity) of the scaffolds far exceeded those of the native leaflet thus showing the importance of studying these properties. The work undergone in this thesis has began to address the requirement for assessing a tissue engineered valve construct at the cellular level (required matrix remodelling) and the mechanical level to aid in the development of a fully functional tissue engineered valve.