2.79j/3.96j/be.441/hst522j cell-matrix interactions m
TRANSCRIPT
Massachusetts Institute of TechnologyMassachusetts Institute of TechnologyHarvard Medical SchoolHarvard Medical School
Brigham and Women’s/Massachusetts General Hosp. Brigham and Women’s/Massachusetts General Hosp. VA Boston Healthcare SystemVA Boston Healthcare System
2.79J/3.96J/BE.441/HST522J2.79J/3.96J/BE.441/HST522J
CELLCELL--MATRIX INTERACTIONSMATRIX INTERACTIONS
M. Spector, Ph.D.M. Spector, Ph.D.
Cell
ExtracellularMatrix
4 mm 10 µm
Articular Cartilage
Chondrocytes (P2 Canine) in a Type I Collagen-GAG Scaffold
Image removed due to copyright considerations.
“Control Volume”
B. Kinner
UNIT CELL PROCESSESUNIT CELL PROCESSESConcept of a “Control Volume” around a CellConcept of a “Control Volume” around a Cell
Cell + Matrix Product + SolubleCell + Matrix Product + Soluble(Regulator) (Regulator) Regulator BRegulator B
“Control Volume”“Control Volume”
SolubleSolubleRegulatorRegulatorAA
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
Image removed due to copyright considerations.
1mm Image removed due to copyright considerations.
• Freeze-dried• Dehydrothermally cross-linked• Additional cross-linking 500µmIV Yannas, et al. PNAS, 1989
CELL CELL ––MATRIX INTERACTIONS WITH MATRIX INTERACTIONS WITH COLLAGENCOLLAGEN--GAG MATRICES GAG MATRICES IN VITROIN VITRO
•• Cell interactions with the scaffoldCell interactions with the scaffold–– Mitosis, migration, synthesis, and Mitosis, migration, synthesis, and
contraction, and their interrelationshipscontraction, and their interrelationships•• Can provide insights into scaffold Can provide insights into scaffold
composition and structure for improved composition and structure for improved performance in regenerative medicineperformance in regenerative medicine
•• Can provide insights into cell behavior Can provide insights into cell behavior in vivoin vivo
Chondrocytes (Passage 2 Canine) in a Type I Collagen-GAG Matrix
Live cell imaging for a period of 5 hours.
Image removed due to copyright considerations.
J. Cheng
CELL CELL ––MATRIX INTERACTIONSMATRIX INTERACTIONS
•• MitosisMitosis•• MigrationMigration•• SynthesisSynthesis•• ContractionContraction
Chondrocyte (P2 Canine) in a Type I Collagen-GAG Matrix:Mitosis
Image removed due to copyright considerations.
J. Cheng
DNA Content
0
10
20
30
40
50
60
0 10 20 30Day
DN
A (u
g)
DHTUVGTAEDAC
CR Lee, et al., Biomat. 2001;22:3145
Mean ± SEM
Effects of CrossEffects of Cross--Linking on Chondrocyte Proliferation Linking on Chondrocyte Proliferation in Type I Collagenin Type I Collagen--GAG MatricesGAG Matrices
Inc. xInc. x--linkinglinking
CELL CELL ––MATRIX INTERACTIONSMATRIX INTERACTIONS
•• MitosisMitosis•• MigrationMigration•• SynthesisSynthesis•• ContractionContraction
Chondrocytes (P2 Canine) in a Type I Collagen-GAG Matrix: Migration and Contraction
Image removed due to copyright considerations.
B. Kinner
CELL CELL ––MATRIX INTERACTIONSMATRIX INTERACTIONS
•• MitosisMitosis•• MigrationMigration•• SynthesisSynthesis•• ContractionContraction
nmol
nmol
/hou
r//h
our/ µµ
g D
NA
g D
NA Protein Synthesis;Protein Synthesis;
ProlineProline IncorporationIncorporation
00
0.050.05
0.10.1
0.150.15
22 77 1515 2929DayDay
ProteoglycanProteoglycan Synthesis;Synthesis;SulfateSulfate IncorporationIncorporation
00
0.010.01
0.020.02
0.030.03
22 77 1515 2929DayDay
UVUVGTAGTAEDCEDC
Effects of CrossEffects of Cross--Linking on Chondrocyte Biosynthesis Linking on Chondrocyte Biosynthesis in Collagenin Collagen--GAG MatricesGAG Matrices
DHTDHT
CR Lee, et al., Biomat. 2001;22:3145
CELL CELL ––MATRIX INTERACTIONSMATRIX INTERACTIONS
•• MitosisMitosis•• MigrationMigration•• SynthesisSynthesis•• ContractionContraction
Chondrocytes (P2 Canine) in a Type I Collagen-GAG Matrix: Contraction
Image removed due to copyright considerations.
40 min B Kinner
Non-Seeded: 8 days21 days
Image removed due to copyright considerations.
Image removed due to copyright considerations.
Non-Seeded and Cell-SeededCollagen-GAG Scaffolds
S. Vickers
Cell-Mediated Contraction
30
40
50
60
70
80
90
100
0 10 20 30Day
% O
rigin
al D
iam
eter
DHTUVGTAEDAC
Mean ± SEM
CR Lee, et al., Biomat. 2001;22:3145
Adult canine articular chondrocytes (passage 3) contract a type I collagen-GAG matrix, reflected in the decrease in diameter
Little x-link., low modulus
Highly x-link., high modulus
CELL CELL ––MATRIX INTERACTIONSMATRIX INTERACTIONS
•• What are the interrelationships What are the interrelationships among among UCPsUCPs: mitosis, synthesis : mitosis, synthesis and contraction?and contraction?
BIOMATERIALSBIOMATERIALS--TISSUE TISSUE INTERACTIONSINTERACTIONS
Cell Cell + Matrix+ MatrixConnectiveConnective
TissueTissueEpitheliaEpitheliaMuscleMuscleNerveNerve
BIOMATERIALSBIOMATERIALS--TISSUE TISSUE INTERACTIONSINTERACTIONS
Cell + Cell + MatrixMatrixConnectiveConnective
TissueTissueEpitheliaEpitheliaMuscleMuscleNerveNerve
AdhesionAdhesionProteinProtein
CollagenCollagenBiomaterialBiomaterial
BIOMATERIALSBIOMATERIALS--TISSUE TISSUE INTERACTIONSINTERACTIONS
Cell Cell ++ MatrixMatrixConnectiveConnective
TissueTissueEpitheliaEpitheliaMuscleMuscleNerveNerve
AdhesionAdhesionProteinProtein
CollagenCollagenBiomaterialBiomaterial
IntegrinIntegrin
“UNIT CELL PROCESSES”“UNIT CELL PROCESSES”
Cell + MatrixCell + MatrixMitosisMitosisSynthesisSynthesisMigrationMigrationContractionContractionEndocytosisEndocytosisExocytosisExocytosis
UCPUCP
ConnectiveConnectiveTissueTissue
EpitheliaEpitheliaMuscleMuscleNerveNerve