Chondrogenic and adipogenic potential of microvascular pericytes.
BACKGROUND
Previous studies have shown that pericytes can differentiate into osteoblasts and form bone. This study investigated whether pericytes can also differentiate into chondrocytes and adipocytes.


RESULTS
Reverse transcription-polymerase chain reaction demonstrated that pericytes express mRNA for the chondrocyte markers Sox9, aggrecan, and type II collagen. Furthermore, when cultured at high density in the presence of a defined chondrogenic medium, pericytes formed well-defined pellets comprising cells embedded in an extracellular matrix rich in sulfated proteoglycans and type II collagen. In contrast, when endothelial cells were cultured under the same conditions, the pellets disintegrated after 48 hours. In the presence of adipogenic medium, pericytes but not endothelial cells expressed mRNA for peroxisome proliferator-activated receptor-gamma2 (an adipocyte-specific transcription factor) and incorporated lipid droplets that stained with oil red O. To confirm that pericytes can differentiate along the chondrocytic and adipocytic lineages in vivo, these cells were inoculated into diffusion chambers and implanted into athymic mice for 56 days. Accordingly, mineralized cartilage, fibrocartilage, and a nonmineralized cartilaginous matrix with lacunae containing chondrocytes were observed within these chambers. Small clusters of cells that morphologically resembled adipocytes were also identified.


CONCLUSIONS
These data demonstrate that pericytes are multipotent cells that may contribute to growth, wound healing, repair, and/or the development and progression of various pathological states.
Farrington-Rock
C
C
Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester M13 9PT, UK.
Crofts
N J
NJ
Doherty
M J
MJ
Ashton
B A
BA
Griffin-Jones
C
C
Canfield
A E
AE
D017667:Adipocytes / Q000166:cytology* / Q000378:metabolism; D053674:Aggrecans; D000818:Animals; D015415:Biomarkers; D002356:Cartilage / Q000166:cytology; D002417:Cattle; D002454:Cell Differentiation; D002478:Cells, Cultured / Q000166:cytology / Q000378:metabolism; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D024043:Collagen Type II / Q000096:biosynthesis / Q000235:genetics; D015194:Diffusion Chambers, Culture; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000235:genetics; D020869:Gene Expression Profiling; D006609:High Mobility Group Proteins / Q000096:biosynthesis / Q000235:genetics; D037181:Lectins, C-Type; D051379:Mice; D008819:Mice, Nude; D047495:PPAR gamma / Q000096:biosynthesis / Q000235:genetics; D020286:Pericytes / Q000166:cytology* / Q000378:metabolism; D011509:Proteoglycans / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D055758:SOX9 Transcription Factor; D014157:Transcription Factors / Q000096:biosynthesis / Q000235:genetics
C508320:Acan protein, mouse; D053674:Aggrecans; D015415:Biomarkers; D024043:Collagen Type II; D016326:Extracellular Matrix Proteins; D006609:High Mobility Group Proteins; D037181:Lectins, C-Type; D047495:PPAR gamma; D011509:Proteoglycans; D055758:SOX9 Transcription Factor; C527933:Sox9 protein, mouse; D014157:Transcription Factors