Programmable cells of monocytic origin (PCMO): a source of peripheral blood stem cells that generate collagen type II-producing chondrocytes.
The focus of this study was a new adult pluripotent cell derived from human peripheral blood monocytes identified as a "programmable cell of monocytic origin" (PCMO). In contrast to bone marrow-derived stem cells, these cells can be harvested from peripheral venous blood without aspiration of the bone marrow and have multilineage potential comparable to that of mesenchymal stem cells (MSC). The aim of this study was to evaluate the potential of PCMOs to differentiate into collagen type II-producing chondrocytes using various extrinsic cues (TGFbeta-1, IGF-1, BMP-2, and BMP-7). Collagen type I and II proteins were localized using immunohistochemistry and quantified by enzyme-linked immunosorbent assays (ELISA). The shape of the differentiating PCMOs was monitored with electron microscopy. Collagen type I and II messenger RNA expression was analyzed using real-time reverse transcriptase-polymerase chain reaction (RT PCR) and regular RT PCR. Immunohistochemistry revealed a strong accumulation of collagen type II after a 6-week incubation period with BMP-2, BMP-7, TGF-beta, IGF-I, and TGF-beta, and IGF-1. Collagen type I was only mildly induced by the applied stimulants. Electron microscopy findings showed a shift from a monocyte-like structure to a chondrocyte-like structure after 2 weeks of stimulation. Stimulation of PCMOs with BMP-2, BMP-7, TGF-beta, IGF-I, and TGF-beta, and IGF-1 induced a chondrogenic differentiation with continuous expression of collagen type II mRNA and protein over several weeks time. Collagen type I and II expression in undifferentiated PCMOs or in control cells incubated without any stimulant was not detected. PCMOs have the potential to differentiate into collagen type II synthesizing chondrocytes. The ability to reprogram and differentiate PCMOs from peripheral blood into sizable quantities might enable their clinical application in cartilage repair after mechanical injury or in cases of osteoarthritis.
Pufe
Thomas
T
Institute for Anatomy, Faculty of Medicine RWTH Aachen, Wendlingweg 2, 52057 Aachen, Germany. tpufe@ukaachen.de
Petersen
Wolf
W
Fändrich
Fred
F
Varoga
Deike
D
Wruck
Christoph J
CJ
Mentlein
Rolf
R
Helfenstein
Andreas
A
Hoseas
Daniela
D
Dressel
Stefanie
S
Tillmann
Bernhard
B
Ruhnke
Maren
M
D001773:Blood Cells / Q000187:drug effects; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology; D054337:Cell Dedifferentiation; D002454:Cell Differentiation; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism*; D024043:Collagen Type II / Q000096:biosynthesis* / Q000235:genetics; D004357:Drug Synergism; D006801:Humans; D007150:Immunohistochemistry; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology; D007377:Interleukin-3 / Q000494:pharmacology; D016173:Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D008854:Microscopy, Electron; D009000:Monocytes / Q000187:drug effects; D039904:Pluripotent Stem Cells / Q000166:cytology* / Q000187:drug effects; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D023822:Tissue Engineering / Q000379:methods; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014680:Veins
C525718:BMP2 protein, human; C525819:BMP7 protein, human; D055396:Bone Morphogenetic Protein 2; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D024043:Collagen Type II; D007377:Interleukin-3; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta; D007334:Insulin-Like Growth Factor I; D016173:Macrophage Colony-Stimulating Factor