Immune and Inflammatory Pathways are Involved in Inherent Bone Marrow Ossification
- 258 Downloads
Bone marrow plays a key role in bone formation and healing. Although a subset of marrow explants ossifies in vitro without excipient osteoinductive factors, some explants do not undergo ossification. The disparity of outcome suggests a significant heterogeneity in marrow tissue in terms of its capacity to undergo osteogenesis.
We sought to identify: (1) proteins and signaling pathways associated with osteogenesis by contrasting the proteomes of ossified and poorly ossified marrow explants; and (2) temporal changes in proteome and signaling pathways of marrow ossification in the early and late phases of bone formation.
Explants of marrow were cultured. Media conditioned by ossified (n = 4) and poorly ossified (n = 4) subsets were collected and proteins unique to each group were identified by proteomic analysis. Proteomic data were processed to assess proteins specific to the early phase (Days 1–14) and late phase (Days 15–28) of the culture period. Pathways involved in bone marrow ossification were identified through bioinformatics.
Twenty-eight proteins were unique to ossified samples and eight were unique to poorly ossified ones. Twelve proteins were expressed during the early phase and 15 proteins were specific to the late phase. Several identified pathways corroborated those reported for bone formation in the literature. Immune and inflammatory pathways were specific to ossified samples.
The marrow explant model indicates the inflammatory and immune pathways to be an integral part of the osteogenesis process.
These results align with the clinically reported negative effects of antiinflammatory agents on fracture healing.
KeywordsVascular Endothelial Growth Factor Notch Signaling Osteoinductive Factor Methyl Methanethiosulfonate Marrow Explants
We thank David VanSickle PhD, DVM for insightful discussions on bone marrow ossification model and Pamela Lachik for help with the μCT system.
- 11.Chiellini C, Cochet O, Negroni L, Samson M, Poggi M, Ailhaud G, Alessi MC, Dani C, Amri EZ. Characterization of human mesenchymal stem cell secretome at early steps of adipocyte and osteoblast differentiation. BMC Mol. Biol. 2008;9.Google Scholar
- 32.Ha BG, Hong JM, Park J-Y, Ha M-H, Kim T-H, Choi J-Y, Ryoo H-M, Choi J-Y, Shi, H-I, Chun SY, Kim S-Y, Park EK. Proteomic profile of osteoclast membrane proteins: identification of Na +/H + exchanger domain containing 2 and its role in osteoclast fusion. Proteomics. 2008;8:2625–2639.PubMedCrossRefGoogle Scholar
- 33.Hasegawa K, Wakino S, Tanaka T, Kimoto M, Tatematsu S, Kanda T, Yoshioka K, Homma K, Sugano N, Kurabayashi M, Saruta T, Hayashi K. Dimethylarginine dimethylaminohydrolase 2 increases vascular endothelial growth factor expression through Sp1 transcription factor in endothelial cells. Arterioscler Thromb Vasc Biol. 2006;26:1488–1494.PubMedCrossRefGoogle Scholar
- 57.Luria EA, Owen M, Friedenstein AJ, Morris J, Kuznetsow SA, Joyner C. Bone formation in organ culture of marrow pieces. Cell Tissue Res. 1986;7:313.Google Scholar
- 77.Oldershaw RA, Tew SR, Russell AM, Meade K, Hawkins R, McKay TR, Brennan KR, Hardingham TE. Notch signaling through jagged-1 is necessary to initiate chondrogenesis in human bone marrow stromal cells but must be switched off to complete chondrogenesis. Stem Cells. 2008;26:666–674.PubMedCrossRefGoogle Scholar
- 81.Pfister O, Oikonomopoulos A, Sereti K-I, Sohn RL, Cullen D, Fine GC, Mouquet F, Westerman K, Liao R. Role of the ATP-binding cassette transporter Abcg2 in the phenotype and function of cardiac side population cells. Circ Res. 2008;103:825-U110.Google Scholar
- 82.Pufe T, Wildemann B, Petersen W, Mentlein R, Raschke M, Schmidmaier G. Quantitative measurement of the splice variants 120 and 164 of the angiogenic peptide vascular endothelial growth factor in the time flow of fracture healing: a study in the rat. Cell Tissue Res. 2002;309:387–392.PubMedCrossRefGoogle Scholar
- 88.Styrkarsdottir U, Halldorsson BV, Gretarsdottir S, Gudbjartsson DF, Walters GB, Ingvarsson T, Jonsdottir T, Saemundsdottir J, Snorradottir S, Center JR, Nguyen TV, Alexandersen P, Gulcher JR, Eisman JA, Christiansen C, Sigurdsson G, Kong A, Thorsteinsdottir U, Stefansson K. New sequence variants associated with bone mineral density. Nat Genet. 2009;41:15–17.PubMedCrossRefGoogle Scholar
- 92.Toyosaki-Maeda T, Takano H, Tomita T, Tsuruta Y, Maeda-Tanimura M, Shimaoka Y, Takahashi T, Itoh T, Suzuki R, Ochi T. Differentiation of monocytes into multinucleated giant bone-resorbing cells: two-step differentiation induced by nurse-like cells and cytokines. Arthritis Res. 2001;3:306–310.PubMedCrossRefGoogle Scholar
- 103.Zhang AX, Yu WH, Ma BF, Yu XB, Mao FF, Liu W, Zhang, JQ, Zhang XM, Li SN, Li MT, Lahn BT, Xiang AP. Proteomic identification of differently expressed proteins responsible for osteoblast differentiation from human mesenchymal stem cells. Mol Cell Biochem. 2007;304:167–179.PubMedCrossRefGoogle Scholar