Soluble factors from ASCs effectively direct control of chondrogenic fate.
OBJECTIVE
Adipose tissue-derived stem cells (ASCs) have great potential for regenerative medicine. For molecular understanding of specific functional molecules present in ASCs, we analysed 756 proteins including specific chondrogenic functional factors, using high-throughput nano reverse-phase liquid chromatography-electrospray ionization-tandem mass spectrometry.


RESULTS
Of these proteins, 33 were identified as chondrogenic factors or proteins including type 2 collagen, biglycan, insulin-like growth factor-binding protein and transforming growth factor-beta 1 (TGF-beta1). ASCs are a possible cell source for cartilage regeneration as they are able to secrete a number of functional cytokines including chondrogenesis-inducing molecules such as TGF-beta1 and bone morphogenetic protein 4 (BMP4). The chondrogenic phenotype of cultured ASCs was effectively induced by ASC-culture media (CM) containing BMP4 and TGF-beta1, and maintained after pre-treatment for 14 days in vitro and subcutaneous implantation in vivo. Chondrogenic differentiation efficiency of cultured ASCs and cultured mouse skin-derived progenitor cells (SPCs) depended absolutely on ASC CM-fold concentration. Cell density was also a very important factor for chondrogenic behaviour development during differentiation of ASCs and SPCs.


CONCLUSIONS
ASC CM-derived TGF-beta1-induced chondrogenic differentiation of ASCs resulted in significant reduction in chondrogenic activity after inhibition of the p38 pathway, revealing involvement of this MAPK pathway in TGF-beta1 signalling. On the other hand, TGF-beta1 signalling also led to SMAD activation that could directly increase chondrogenic activity of ASCs.
Kim
B-S
BS
Department of Veterinary Biotechnology, College of Veterinary Medicine, Seoul National University, Seoul, Korea.
Kang
K-S
KS
Kang
S-K
SK
D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D019070:Cell Lineage / Q000187:drug effects / Q000502:physiology*; D020219:Chondrogenesis / Q000187:drug effects / Q000502:physiology*; D002853:Chromatography, Liquid; D017077:Culture Media, Conditioned / Q000494:pharmacology; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000502:physiology; D013058:Mass Spectrometry; D051379:Mice; D008813:Mice, Inbred ICR; D040901:Proteomics; D033581:Stem Cell Transplantation / Q000379:methods; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism / Q000494:pharmacology
D017077:Culture Media, Conditioned; D016207:Cytokines; D036341:Intercellular Signaling Peptides and Proteins; D053773:Transforming Growth Factor beta1