Massachusetts Institute of Technology Harvard Medical School Brigham and Womens Hospital VA Boston Healthcare System 2.79J/3.96J/BE44I/HST522J BIOMATERIALS-TISSUE INTERACTIONS Tools"for Understanding the Molecular, Cellular, and Physiological, Bases of the Tissue Response to Implants M. Spector, Ph D. and I.V. Yannas, Ph. D BIOMATERIALS-TISSUE INTERACTIONS Tissue* Biomaterials Cell Matrix* Structure comprising cells of the same type 会 Solid surface Page 1
2.79J/3.96J/BE.441/HST522J BIOMATERIALS-TISSUE INTERACTIONS: “Tools” for Understanding the Molecular, Cellular, and Physiological, Bases of the Tissue Response to Implants M. Spector, Ph.D. and I.V. M. Spector, Ph.D. and I.V. Yannas, Ph.D. Massachusetts Institute of Technology Harvard Medical School Brigham and Women’s Hospital VA Boston Healthcare System BIOMATERIALS BIOMATERIALS-TISSUE INTERACTIONS INTERACTIONS Tissue* + Biomaterial** Tissue* + Biomaterial** Cell+Matrix** Matrix** * Structure comprising cells of the same type ** Solid surface Page 1
CELL-MATRIX INTERACTIONS In Tissue Cell Extracellular Matrix In Tissue Engineering Scaffolds Cell Biomaterial Scaffold CONCEPTS FOR UNDERSTANDING BIOMATERIALS-TISSUE INTERACTIONS Control volume Unit cell Processes Types of Ti Issues Tissue formation and remodeling in vitro Wound healing in vivo Page 2
In Tissue In Tissue Cell + Extracellular Extracellular Matrix In Tissue Engineering Scaffolds In Tissue Engineering Scaffolds Cell + Biomaterial Scaffold Cell + Biomaterial Scaffold CELL-MATRIX INTERACTIONS MATRIX INTERACTIONS CONCEPTS FOR UNDERSTANDING CONCEPTS FOR UNDERSTANDING BIOMATERIALS-TISSUE INTERACTIONS • Control Volume • Unit Cell Processes • Types of Tissues • Tissue Formation and Remodeling Tissue Formation and Remodeling In Vitro • Wound Healing Wound Healing In Vivo Page 2
Articular Cartilage A Cell Chondrocytes(P2 Canine)in a Type I Collagen-GAGScaffold Image removed due to copyright considerations. “ Control volun Source:B. Kinner Page 3
2 Cell Matrix Extracellular Articular Cartilage 5 3 1 4 6 40min Chondrocytes (P2 Canine) in a . Source: B. Kinner Type I Collagen-GAG Scaffold B. Kinner “Control Volume” Image removed due to copyright considerations Page 3
UNIT CELL PROCESSES Concept of a“ Control Volume” around a Cell Soluble Regulator Cell+ Matrix Product+Soluble (Regulator) Regulator b Control volume UNIT CELL PROCESSES Concept of a“ Control volume” around a cel Soluble Regulator Mechanical oading(Strain) Cell Matrix Product+ Soluble (Regulator) Regulator B “ Control volume” Page 4
UNIT CELL PROCESSES Concept of a “Control Volume” around a Cell Cell + Matrix Product Product + Soluble (Regulator) (Regulator) Regulator B “Control Volume” Soluble Regulator A UNIT CELL PROCESSES Concept of a “Control Volume” around a Cell Cell + Matrix Product Product + Soluble (Regulator) (Regulator) Regulator B “Control Volume” Soluble Regulator A Mechanical Loading (Strain) Page 4
CONCEPTS FOR UNDERSTANDING BIOMATERIALS-TISSUE INTERACTIONS Control volume Unit cell processes Types of Tissues Tissue formation and remodeling n vitro Wound Healing In vivo UNIT CELL PROCESSES Mitosis Migration Synthesis Contraction Endocytosis Exocytosis Page 5
CONCEPTS FOR UNDERSTANDING CONCEPTS FOR UNDERSTANDING BIOMATERIALS-TISSUE INTERACTIONS • Control Volume • Unit Cell Processes • Types of Tissues • Tissue Formation and Remodeling Tissue Formation and Remodeling In Vitro • Wound Healing Wound Healing In Vivo UNIT CELL PROCESSES UNIT CELL PROCESSES • Mitosis • Migration • Synthesis • Contraction • Endocytosis • Exocytosis Page 5
COLLAGEN-GAG MATRICES: MODEL BIOMATERIALS (ANALOGS OF EXTRACELLULAR MATRIX) Investigation of cell interactions(UCPs)in vitro Type I (bovine and porcine) ype II( e) Chondroitin 6-sulfate copyright considerations Image removed due to opyright considerations Imm · Freeze- dried Dehydrothermally cross-linked Additional cross-linking 500um CELL-MATRIX INTERACTIONS WITH COLLAGEN-GAG MATRICES IN VITRO an provide insights into interrelationships among cell processes How do mitosis and synthesis interrelate? How do mitosis and synthesis relate to contraction? How does migration relate to contraction? an provide insights into cell behavior in vivo Can provide insights into scaffold composition and structure for improved performance in regenerative medicine Page 6
1mm 500mm COLLAGEN-GAG MATRICES: MODEL BIOMATERIALS (ANALOGS OF EXTRACELLULAR MATRIX) Investigation of cell interactions (UCPs ) in vitro • Type I (bovine and porcine) • Type II (porcine) • Chondroitin 6-sulfate • Freeze -dried • Dehydrothermally cross-linked • Additional cross-linking IV Yannas, et al. PNAS, 1989 Image removed due to copyright considerations. Image removed due to copyright considerations. CELL –MATRIX INTERACTIONS WITH MATRIX INTERACTIONS WITH COLLAGEN-GAG MATRICES GAG MATRICES IN VITRO • Can provide insights into interrelationships Can provide insights into interrelationships among cell processes. – How do mitosis and synthesis interrelate? – How do mitosis and synthesis relate to How do mitosis and synthesis relate to contraction? – How does migration relate to contraction? • Can provide insights into cell behavior Can provide insights into cell behavior in vivo. • Can provide insights into scaffold composition Can provide insights into scaffold composition and structure for improved performance in and structure for improved performance in regenerative medicine. Page 6
Chondrocytes(Passage 2 Canine) in a Type I Collagen-GAG Matrix ve cell imaging for a period of 5 hour mage removed due to copyright considerations J. Cheng CELL-MATRIX INTERACTIONS Mitosis Migration Contraction Page 7
Chondrocytes (Passage 2 Canine) in a Type I Collagen-GAG Matrix J. Cheng Live cell imaging for a period of 5 hours. Image removed due to copyright considerations. CELL–MATRIX INTERACTIONS MATRIX INTERACTIONS • Mitosis • Migration • Synthesis • Contraction Page 7
Chondrocyte(P2 Canine) in a Type I Collagen GAG matrix Mitosis J. Cheng Effects of Cross-Linking on Chondrocyte Proliferation in Collagen-GAG Matrices Mean±SEM - DHT GTA EDAC 0 10 20 30 Day Page 8
DNA Content Chondrocyte (P2 Canine) in a Type I Collagen-GAG Matrix: Mitosis J. Cheng 0 10 20 30 40 50 60 0 10 20 30 Day DNA (ug) DHT UV GTA EDAC CR Lee, et al., Biomat. 2001;22:3145 Mean – SEM Effects of Cross-Linking on Chondrocyte Proliferation Linking on Chondrocyte Proliferation in Collagen-GAG Matrices Page 8
CELL-MATRIX INTERACTIONS Mitosis Migration Contraction 40min Chondrocytes(P2 Canine) in a Type I Collagen GAG Matrix: Migration and Contraction B. Kinner Page 9
CELL–MATRIX INTERACTIONS MATRIX INTERACTIONS • Mitosis • Migration • Synthesis • Contraction 40min Chondrocytes (P2 Canine) in a Type I Collagen GAG Matrix: Migration and Contraction B. Kinner Page 9
CELL-MATRIX INTERACTIONS Mitosis Migration Synthesis Contraction Effects of Cross-Linking on Chondrocyte Biosynthesis in Collagen-GAG Matrices Protein Synthesis; Proteoglycan Synthesis Proline Incorporation 0.03 ulfate Incorporation 0.02 0.05 0.01 Day Da ■ DHT UV■ GTA EDO CR Lee, et al. Biomat. 2001;22:3145 Page 11
CELL–MATRIX INTERACTIONS MATRIX INTERACTIONS • Mitosis • Migration • Synthesis • Contraction Protein Synthesis; Proline Incorporation 0 0.05 0.1 0.15 2 7 15 29 Day nmol/hour/ mg DNA Proteoglycan Synthesis; Sulfate Incorporation 0 0.01 0.02 0.03 2 7 15 29 Day DHT UV GTA EDC Effects of Cross-Linking on Chondrocyte Biosynthesis Linking on Chondrocyte Biosynthesis in Collagen-GAG Matrices CR Lee, et al., Biomat. 2001;22:3145 Page 11
