Human bone tissue formation in diffusion chamber culture in vivo by bone-derived cells and marrow stromal fibroblastic cells

OBJECTIVE: Osteoprotegerin (OPG) and its ligand 'receptor activator of NF-kB ligand' (RANKL) are important regulators of bone metabolism. RANKL, expressed in osteoblasts, activates osteoclast differentiation and osteoclast function by binding the 'receptor activator of NF-kB' (RANK), expressed in ostoclast precursors and mature osteoclasts. The effect is prevented by OPG, a soluble receptor of RANKL. In vitro studies have suggested that estrogen stimulates OPG, whereas parathyroid hormone (PTH) inhibits OPG expression and stimulates the expression of RANKL. DESIGN: In the present study, we examined the relationship between the menopause, serum PTH and the expression of OPG and RANKL in human bone tissue in vivo. METHODS: To address this question, we established a 5'-nuclease assay to quantify the mRNA copies of human OPG and RANKL, normalized to the number of copies of beta-actin mRNA in 169 women (mean age: 52.4+/-11.6 years), who underwent surgery for early breast cancer. Intact serum PTH was measured by chemoluminescence in 61 women. RESULTS: We found no significant difference in the expression of OPG and RANKL between postmenopausal women and premenopausal women. Also, the ratio of RANKL to OPG was unchanged in relation to the menopausal status. Serum PTH was negatively associated with the expression of OPG (r=-0.33, P=0.01), but also, surprisingly, with the expression of RANKL (r=-0.28, P=0.03). CONCLUSION: We failed to observe the expected changes in the expression of OPG and RANKL in human bone samples at menopause. High in vivo levels of circulating PTH are accompanied by low levels of expression of the two transcripts in human bone tissue.

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In Vivo Bone Tissue Formation Induced by Caclium Phosphate Paste Composite with Demineralized Bone Matrix

Key Engineering Materials - Bioceramics 19 ◽

10.4028/0-87849-422-7.1091 ◽

2007 ◽

pp. 1091-1094

Author(s):

H. Kim ◽

M. Park ◽

Su Young Lee ◽

Kang Yong Lee ◽

Hyun Min Kim ◽

...

Keyword(s):

Bone Tissue ◽

Demineralized Bone Matrix ◽

Bone Matrix ◽

Tissue Formation ◽

Bone Tissue Formation ◽

Demineralized Bone

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Antigenic Profile of Osteoblasts Present in Human Bone Tissue Sections

Bioscience Reports ◽

10.1007/s10540-006-9006-z ◽

2006 ◽

Vol 26 (1) ◽

pp. 39-43 ◽

Cited By ~ 16

Author(s):

O. García-Martínez ◽

C. Reyes-Botella ◽

O. Aguilera-Castillo ◽

M.F. Vallecillo-Capilla ◽

C. Ruiz

Keyword(s):

Bone Tissue ◽

Primary Cultures ◽

Human Bone ◽

Immunoperoxidase Technique ◽

Tissue Sections ◽

Hla Dr ◽

Human Bone Tissue ◽

Fetal Bovine ◽

Antigenic Profile

The antigenic profile of human osteoblasts was previously analyzed by our group using primary cultures as study samples. These studies suggested a novel functional approach to this cell population. Osteoblasts have a characteristic antigenic profile and share antigens in common with other cell populations that also originate in the bone marrow. Some of the detected antigens are constitutively expressed, while others are modulated by different factors and/or cytokines. The aim of the present study was to analyze the antigens present in osteoblasts in vivo, since the presence of certain biomolecules in fetal bovine serum may modulate the antigenic expression, compromising the results. For this purpose, human bone tissue sections were analyzed with a wide panel of mAbs and using the immunoperoxidase technique. CD10, CD44 and alkaline phosphatase antigens and IL-12, IL-18 and IFNγ cytokines were detected in osteoblasts in the bone tissue. However, CD80 and HLA-DR antigens were not found in all samples and when present their expression was weak. The expression of CD54 antigen was moderate or weak. These results allow data obtained by the primary culture of osteoblast-like cells to be endorsed.

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In vivo tissue response and antibacterial efficacy of minocycline delivery system based on polymethylmethacrylate bone cement

Journal of Biomaterials Applications ◽

10.1177/0885328218795290 ◽

2018 ◽

Vol 33 (3) ◽

pp. 380-391 ◽

Cited By ~ 2

Author(s):

Tiago Silva ◽

Jose C Silva ◽

Bruno Colaco ◽

Adelina Gama ◽

Margarida Duarte-Araújo ◽

...

Keyword(s):

Antibacterial Activity ◽

Bone Cement ◽

Bone Tissue ◽

Delivery System ◽

Biological Evaluation ◽

Release Profile ◽

Tissue Formation ◽

Tissue Implantation ◽

Bone Tissue Formation

This study aims the in vivo biological characterization of an innovative minocycline delivery system, based on polymethylmethacrylate bone cement. Bone cements containing 1% or 2.5% (w/w) minocycline were formulated and evaluated through solid-state characterization. Biological evaluation was conducted in vivo, within a rat model, following the subcutaneous and bone tissue implantation, and tissue implantation associated with Staphylococcus aureus is challenging. The assessment of the tissue/biomaterial interaction was conducted by histologic, histomorphometric and microtomographic techniques. Minocycline addition to the composition of the polymethylmethacrylate bone cement did not modify significantly the cement properties. Drug release profile was marked by an initial burst release followed by a low-dosage sustained release. Following the subcutaneous tissue implantation, a reduced immune-inflammatory reaction was verified, with diminished cell recruitment and a thinner fibro-connective capsule formation. Minocycline-releasing cements were found to enhance the bone-to-implant contact and bone tissue formation, following the tibial implantation. Lastly, an effective antibacterial activity was mediated by the implanted cement following the tissue challenging with S. aureus. Kinetic minocycline release profile, attained with the developed polymethylmethacrylate system, modulated adequately the in vivo biological response, lessening the immune-inflammatory activation and enhancing bone tissue formation. Also, an effective in vivo antibacterial activity was established. These findings highlight the adequacy and putative application of the developed system for orthopedic applications.

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