The heterogeneity of human mesenchymal stem cell preparations--evidence from simultaneous analysis of proteomes and transcriptomes.
OBJECTIVE
Mesenchymal stem cells (MSC) raise high hopes in clinical applications. However, the lack of common standards and a precise definition of MSC preparations remains a major obstacle in research and application of MSC. Whereas surface antigen markers have failed to precisely define this population, a combination of proteomic data and microarray data provides a new dimension for the definition of MSC preparations.


METHODS
In our continuing effort to characterize MSC, we have analyzed the differential transcriptome and proteome expression profiles of MSC preparations isolated from human bone marrow under two different expansion media (BM-MSC-M1 and BM-MSC-M2).


RESULTS
In proteomics, 136 protein spots were unambiguously identified by MALDI-TOF-MS and corresponding cDNA spots were selected on our "Human Transcriptome cDNA Microarray." Combination of datasets revealed a correlation in differential gene expression and protein expression of BM-MSC-M1 vs BM-MSC-M2. Genes involved in metabolism were more highly expressed in BM-MSC-M1, whereas genes involved in development, morphogenesis, extracellular matrix, and differentiation were more highly expressed in BM-MSC-M2. Interchanging culture conditions for 8 days revealed that differential expression was retained in several genes whereas it was altered in others.


CONCLUSIONS
Our results have provided evidence that homogeneous BM-MSC preparations can reproducibly be isolated under standardized conditions, whereas culture conditions exert a prominent impact on transcriptome, proteome, and cellular organization of BM-MSC.
Department of Medicine V, University of Heidelberg, Germany.
Wolfgang
W
Wagner
Robert E
RE
Feldmann
Anja
A
Seckinger
Martin H
MH
Maurer
Frederik
F
Wein
Jonathon
J
Blake
Ulf
U
Krause
Armin
A
Kalenka
Heinrich F
HF
Bürgers
Rainer
R
Saffrich
Patrick
P
Wuchter
Wolfgang
W
Kuschinsky
Anthony D
AD
Ho
D018929:Cell Culture Techniques / Q000379:methods / Q000592:standards; D002469:Cell Separation / Q000379:methods / Q000592:standards; D002478:Cells, Cultured; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D020543:Proteome / Q000235:genetics / Q000378:metabolism* / Q000592:standards; D015203:Reproducibility of Results; D014158:Transcription, Genetic / Q000502:physiology*
D020543:Proteome