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Li J, Sun H, Guan J, Li B, Jin C, Xie S, Liu Y. Immunogenicity of chondrocyte sheets: a review. Front Immunol 2025; 16:1529384. [PMID: 40124370 PMCID: PMC11926542 DOI: 10.3389/fimmu.2025.1529384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2024] [Accepted: 02/21/2025] [Indexed: 03/25/2025] Open
Abstract
The chondrocyte sheet is a sheet-like cell structure obtained by separating in vitro expanded and fused autologous chondrocytes from the bottom of the culture dish by physical means. The cell sheet contains autologous chondrocytes, extracellular matrix secreted by chondrocytes, and connective structures established between cells and matrix, and between cells and cells. In cartilage tissue engineering, chondrocyte sheets technology has great potential for the treatment of cartilage defects. Chondrocyte sheets have a low immunogenicity because they avoid the immune reaction caused by scaffolding materials. However, chondrocyte sheets can still cause severe local tissue swelling in the short term after implantation, resulting in a poor patient experience. In individual cases, an inflammatory reaction may even occur, leading to resorption of the chondrocyte sheet. This may be immunogenetically related to chondrocyte membrane surface-associated antigens, components of the extracellular matrix secreted by chondrocytes, and various bioactive components in the culture medium used during in vitro chondrocyte culture. Therefore, in order to investigate the causes of local tissue swelling and immune-inflammatory reactions induced by the implantation of chondrocyte sheets, this article reviews the immunogenicity of chondrocyte-associated antigens, components of the extracellular matrix of cartilage, and the active components of the cell culture medium.
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Affiliation(s)
- Juncen Li
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Huilin Sun
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Jiaqi Guan
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Bohui Li
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Chen Jin
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Shanhong Xie
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
| | - Yu Liu
- College of Clinical Medicine, Shandong Second Medical University, Weifang, China
- Department of Plastic and Reconstructive Surgery, Shanghai 9th People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Tissue Engineering, Shanghai, China
- National Tissue Engineering Center of China, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Resthetic Biotechnology. Co., Ltd, Shanghai, China
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Abstract
The collagen-induced arthritis mouse model is a widely studied autoimmune model of rheumatoid arthritis. In this model, autoimmune arthritis is induced by immunization of genetically susceptible strains of mice with type II collagen emulsified in complete Freund's adjuvant. This article describes the steps necessary for the acquisition, handling, and preparation of CII, in addition to the selection of mouse strains, proper immunization technique, and methods for evaluation of the incidence and severity of the autoimmune arthritis. In this model, the first signs of arthritis appear approximately 21 to 28 days after immunization. The protocols in this article should provide the investigator with all the necessary information required to reproducibly induce a high incidence of CIA in genetically susceptible strains of mice, and to critically evaluate the pathology of the disease. Published 2021. This article is a U.S. Government work and is in the public domain in the USA. Basic Protocol: Induction of collagen-induced arthritis Support Protocol 1: Purification of type II collagen Support Protocol 2: Purification of type II collagen α1(II) chains Support Protocol 3: Assessment of arthritis incidence and severity Support Protocol 4: Measurement of CII specific antibody by indirect ELISA Support Protocol 5: Coupling CII to magnetic beads Support Protocol 6: Measuring CII-specific antibody by magnetic-bead based ELISA Support Protocol 7: Measurement of T cell responses to CII in CIA.
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Affiliation(s)
- Edward F Rosloniec
- Veterans Affairs Medical Center, Memphis, Tennessee
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
- Department of Pathology, University of Tennessee Health Science Center, Memphis, Tennessee
| | | | | | - David D Brand
- Veterans Affairs Medical Center, Memphis, Tennessee
- Department of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee
- Departments of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee
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Susukida T, Aoki S, Shirayanagi T, Yamada Y, Kuwahara S, Ito K. HLA transgenic mice: application in reproducing idiosyncratic drug toxicity. Drug Metab Rev 2020; 52:540-567. [PMID: 32847422 DOI: 10.1080/03602532.2020.1800725] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Various types of transgenic mice carrying either class I or II human leukocyte antigen (HLA) molecules are readily available, and reports describing their use in a variety of studies have been published for more than 30 years. Examples of their use include the discovery of HLA-specific antigens against viral infection as well as the reproduction of HLA-mediated autoimmune diseases for the development of therapeutic strategies. Recently, HLA transgenic mice have been used to reproduce HLA-mediated idiosyncratic drug toxicity (IDT), a rare and unpredictable adverse drug reaction that can result in death. For example, abacavir-induced IDT has successfully been reproduced in HLA-B*57:01 transgenic mice. Several reports using HLA transgenic mice for IDT have proven the utility of this concept for the evaluation of IDT using various HLA allele combinations and drugs. It has become apparent that such models may be a valuable tool to investigate the mechanisms underlying HLA-mediated IDT. This review summarizes the latest findings in the area of HLA transgenic mouse models and discusses the current challenges that must be overcome to maximize the potential of this unique animal model.
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Affiliation(s)
- Takeshi Susukida
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan.,Laboratory of Cancer Biology and Immunology, Section of Host Defenses, Institute of Natural Medicine, University of Toyama, Toyama, Japan
| | - Shigeki Aoki
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Tomohiro Shirayanagi
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Yushiro Yamada
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Saki Kuwahara
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Kousei Ito
- Laboratory of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan
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Rosloniec EF, Cremer M, Kang AH, Myers LK, Brand DD. Collagen-induced arthritis. CURRENT PROTOCOLS IN IMMUNOLOGY 2010; Chapter 15:15.5.1-15.5.25. [PMID: 20376842 DOI: 10.1002/0471142735.im1505s89] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The mouse model collagen-induced arthritis (CIA) is a widely studied autoimmune model of rheumatoid arthritis. In this model, autoimmune arthritis is induced by immunization with type II collagen (CII) emulsified in complete Freund's adjuvant. This unit describes the steps necessary for the acquisition, handling, and preparation of CII, in addition to the selection of mouse strains, proper immunization technique, and methods for evaluation of the incidence and severity of arthritis. In this model, the first signs of arthritis appear approximately 21 to 28 days after immunization. The protocols in this unit should provide the investigator with all the necessary information required to reproducibly induce a high incidence of CIA in genetically susceptible strains of mice, and to critically evaluate the pathology of the disease.
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Affiliation(s)
- Edward F Rosloniec
- Veterans Affairs Medical Center, and University of Tennessee Health Science Center, Memphis, Tennessee
| | - Michael Cremer
- Veterans Affairs Medical Center, and University of Tennessee Health Science Center, Memphis, Tennessee
| | - Andrew H Kang
- Veterans Affairs Medical Center, and University of Tennessee Health Science Center, Memphis, Tennessee
| | - Linda K Myers
- Veterans Affairs Medical Center, and University of Tennessee Health Science Center, Memphis, Tennessee
| | - David D Brand
- Veterans Affairs Medical Center, and University of Tennessee Health Science Center, Memphis, Tennessee
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Greidinger EL, Zang Y, Fernandez I, Berho M, Nassiri M, Martinez L, Hoffman RW. Tissue targeting of anti-RNP autoimmunity: effects of T cells and myeloid dendritic cells in a murine model. ARTHRITIS AND RHEUMATISM 2009; 60:534-42. [PMID: 19180485 PMCID: PMC3059848 DOI: 10.1002/art.24256] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To explore the role of immune cells in anti-RNP autoimmunity in a murine model of pneumonitis or glomerulonephritis, using adoptive transfer techniques. METHODS Donor mice were immunized with 50 mug of U1-70-kd small nuclear RNP fusion protein and 50 mug of U1 RNA adjuvant. Whole splenocytes as well as CD4+ cell and dendritic cell (DC) subsets from the immunized mice were infused into naive syngeneic recipients. Anti-RNP and T cell responses were assessed by immunoblotting, enzyme-linked immunosorbent assay, and flow cytometry. Development of renal or lung disease was assessed by histology and urinalysis. RESULTS Unfractionated splenocytes from donor mice without proteinuria induced predominantly lung disease in recipients (8 [57%] of 14 versus 2 [14%] of 14 developing renal disease; P = 0.046). However, infusion of CD4+ cells from donors without proteinuria induced renal disease more frequently than lung disease (7 [70%] of 10 versus 2 [20%] of 10; P = 0.01); adoptive transfer of RNP+CD4+ T cells from short-term culture yielded similar results (renal disease in 8 [73%] of 11 recipients versus lung disease in 3 [27%] of 11). Cotransfer of splenic myeloid DCs and CD4+ T cells from immunized donors prevented induction of renal disease in all 5 recipients (P = 0.026 versus recipients of fresh CD4+ cells alone), although lung disease was still observed in 1 of 5 mice. Transfer of myeloid DCs alone from immunized donors induced lung disease in 3 (60%) of 5 recipients, without evidence of nephritis. Cotransfer of splenocytes from mice with and those without nephritis led to renal disease in 4 of 5 recipients, without evidence of lung disease. CONCLUSION These findings indicate that RNP+CD4+ T cells are sufficient to induce anti-RNP autoimmunity, tissue targeting in anti-RNP autoimmunity can be deviated to either a renal or pulmonary phenotype depending on the presence of accessory cells such as myeloid DCs, and DC subsets can play a role in both propagation of autoimmunity and end-organ targeting.
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Affiliation(s)
- Eric L Greidinger
- Miami VA Medical Center, and University of Miami Miller School of Medicine, Miami, Florida, USA.
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Kawamura K, Yao K, Shukaliak-Quandt JA, Huh J, Baig M, Quigley L, Ito N, Necker A, McFarland HF, Muraro PA, Martin R, Ito K. Different development of myelin basic protein agonist- and antagonist-specific human TCR transgenic T cells in the thymus and periphery. THE JOURNAL OF IMMUNOLOGY 2008; 181:5462-72. [PMID: 18832703 DOI: 10.4049/jimmunol.181.8.5462] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Myelin basic protein (MBP)-specific T cells are thought to play a role in the development of multiple sclerosis. MBP residues 111-129 compose an immunodominant epitope cluster restricted by HLA-DRB1*0401. The sequence of residues 111-129 of MBP (MBP(111-129)) differs in humans (MBP122:Arg) and mice (MBP122:Lys) at aa 122. We previously found that approximately 50% of human MBP(111-129) (MBP122:Arg)-specific T cell clones, including MS2-3C8 can proliferate in response to mouse MBP(111-129) (MBP122:Lys). However, the other half of T cell clones, including HD4-1C2, cannot proliferate in response to MBP(111-129) (MBP122:Lys). We found that MBP(111-129) (MBP122:Lys) is an antagonist for HD4-1C2 TCR, therefore, MS2-3C8 and HD4-1C2 TCRs are agonist- and antagonist-specific TCRs in mice, respectively. Therefore, we examined the development of HD4-1C2 TCR and MS2-3C8 TCR transgenic (Tg) T cells in the thymus and periphery. We found that dual TCR expression exclusively facilitates the development of MBP(111-129) TCR Tg T cells in the periphery of HD4-1C2 TCR/HLA-DRB1*0401 Tg mice although it is not required for their development in the thymus. We also found that MS2-3C8 TCR Tg CD8(+) T cells develop along with MS2-3C8 TCR Tg CD4(+) T cells, and that dual TCR expression was crucial for the development of MS2-3C8 TCR Tg CD4(+) and CD8(+) T cells in the thymus and periphery, respectively. These results suggest that thymic and peripheral development of MBP-specific T cells are different; however, dual TCR expression can facilitate their development.
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Affiliation(s)
- Kazuyuki Kawamura
- Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, Bethesda, MD 20892, USA
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Brintnell W, Bell DA, Hill JA, Jevnikar AM, Sette A, Sidney J, Doege K, Cairns E. The Influence of MHC Class II Molecules Containing the Rheumatoid Arthritis Shared Epitope on the Immune Response to Aggrecan G1 and Its Peptides. Scand J Immunol 2007; 65:444-52. [PMID: 17444955 DOI: 10.1111/j.1365-3083.2007.01931.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Aggrecan has been implied as an autoantigen in rheumatoid arthritis (RA). Immunization with aggrecan induces arthritis in BALB/c (H-2(d)) mice but not in other strains of mice [e.g. C57BL/6 (H-2(b))]. In humans, the strongest genetic association with RA is to the shared epitope (SE), and aggrecan peptides are predicted to bind to the SE. Therefore, we hypothesized that C57BL/6 mice transgenic (tg) for the RA SE (DR4 tg mice) may be susceptible to aggrecan-induced arthritis. C57BL/6 and DR4 tg mice were immunized with a mixture of SE-binding aggrecan peptides and tested for immune responses to the corresponding peptides as well as aggrecan. Sustained T- and B-cell immune responses to aggrecan and several of its peptides were detected in DR4 tg mice. C57BL/6 mice showed only transient T-cell responses to different immunizing peptides and little B-cell response. Therefore, an immune response to peptides of aggrecan can be induced experimentally in DR4 tg mice as anticipated from the predicted and actual binding affinities of these peptides for the RA SE. Failure to induce arthritis in these DR4 tg mice may be due to a lack of appropriate non-MHC genes.
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Affiliation(s)
- W Brintnell
- Department of Medicine, University of Western Ontario, London, ON, Canada
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Liu Z, Xu X, Hsu HC, Tousson A, Yang PA, Wu Q, Liu C, Yu S, Zhang HG, Mountz JD. CII-DC-AdTRAIL cell gene therapy inhibits infiltration of CII-reactive T cells and CII-induced arthritis. J Clin Invest 2003; 112:1332-41. [PMID: 14597760 PMCID: PMC228459 DOI: 10.1172/jci19209] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Previously, we described an APC-adenovirus (APC-Ad) FasL cell gene therapy method which could be used to deplete autoreactive T cells in vivo. FasL was toxic, however, and controlled regulation of FasL was not achieved. Here we describe an improved approach to delivering TNF-related apoptosis-inducing ligand (TRAIL) in vivo in which collagen II-induced (CII-induced) arthritis-susceptible (CIA-susceptible) DBA/1j mice were treated with CII-pulsed DCs that had been transfected with a novel Ad system. The Ad was engineered to exhibit inducible TRAIL under the control of the doxycycline-inducible (DOX-inducible) tetracycline response element (TRE). Four groups of mice were treated with CII-DC-AdTRAIL+DOX, CII-DC-AdTRAIL (no DOX), CII-DC-AdGFP+DOX, or DC-AdTRAIL+DOX (no CII), beginning 2 weeks after priming with CII in CFA. The incidence of arthritis and infiltration of T cells in the joint was significantly decreased in CII-DC-AdTRAIL+DOX-treated mice. The in vitro splenic T cell proliferative response and induction of IFN-gamma to bovine CII stimulation were also significantly reduced in mice treated with CII-DC-AdTRAIL+DOX. AdTRAIL+DOX was not toxic to DCs or mice but could induce activated T cells to undergo apoptosis in the spleen. Our results suggest that CII-DC-AdTRAIL+DOX cell gene therapy is a safe and effective method for inhibiting the development of CIA.
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Affiliation(s)
- Zhongyu Liu
- Department of Medicine, Division of Clinical Immunology and Rheumatology, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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Liu Z, Xu X, Hsu HC, Tousson A, Yang PA, Wu Q, Liu C, Yu S, Zhang HG, Mountz JD. CII-DC-AdTRAIL cell gene therapy inhibits infiltration of CII-reactive T cells and CII-induced arthritis. J Clin Invest 2003. [DOI: 10.1172/jci200319209] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Bäcklund J, Nandakumar KS, Bockermann R, Mori L, Holmdahl R. Genetic Control of Tolerance to Type II Collagen and Development of Arthritis in an Autologous Collagen-Induced Arthritis Model. THE JOURNAL OF IMMUNOLOGY 2003; 171:3493-9. [PMID: 14500645 DOI: 10.4049/jimmunol.171.7.3493] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
T cell recognition of the type II collagen (CII) 260-270 peptide is a bottleneck for the development of collagen-induced arthritis (CIA), an animal model of rheumatoid arthritis. We have earlier made C3H.Q mice expressing CII with glutamic acid instead of aspartic acid at position 266 (the MMC-C3H.Q mouse), similar to the rat and human CII epitope, which increases binding to MHC class II and leads to effective presentation of the peptide in vivo. These mice show T cell tolerance to CII, but also develop severe arthritis. The present investigation shows that non-MHC genes play a decisive role in determining tolerance and arthritis susceptibility. We bred MMC into B10.Q mice, which display similar susceptibility to CIA induced with rat CII as the C3H.Q mice. In contrast to MMC-C3H.Q mice, MMC-B10.Q mice were completely resistant to arthritis. Nontransgenic (B10.Q x C3H.Q)F(1) mice were more susceptible to CIA than either of the parental strains, but introduction of the MMC transgene leads to CIA resistance, showing that the protection is dominantly inherited from B10.Q. In an attempt to break the B10-mediated CIA protection in MMC-transgenic mice, we introduced a transgenic, CII-specific, TCR beta-chain specific for the CII(260-270) glycopeptide, in the highly CIA-susceptible (B10.Q x DBA/1)F(1) mice. The magnification of the autoreactive CII-specific T cell repertoire led to increased CIA susceptibility, but the disease was less severe than in mice lacking the MMC transgene. This finding is important for understanding CIA and perhaps also rheumatoid arthritis, as in both diseases MHC class II-restricted T cell recognition of the glycosylated CII peptide occurs.
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Affiliation(s)
- Johan Bäcklund
- Section of Medical Inflammation Research, Lund University, Lund, Sweden
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Zhou H, Iida-Klein A, Lu SS, Ducayen-Knowles M, Levine LR, Dempster DW, Lindsay R. Anabolic action of parathyroid hormone on cortical and cancellous bone differs between axial and appendicular skeletal sites in mice. Bone 2003; 32:513-20. [PMID: 12753867 DOI: 10.1016/s8756-3282(03)00057-7] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The mouse is being increasingly used to study the anabolic action of parathyroid hormone (PTH) on the skeleton. The efficacy of intermittent PTH treatment on bone varies widely among tested strains of mice with differences in peak bone mass and structure. We have therefore examined the responses of skeletal sites with high or low cancellous bone mass to PTH treatment in a single strain with genetically low bone mass. Mature C57BL/6 mice were ovariectomized (ovx) or sham operated and, after 4 weeks, treated with PTH(1-34) (40 microg/kg/day, 5 days/week sc) or vehicle for 3 or 7 weeks. Two doses of fluorescent labels were given to the animals 9 and 3 days before euthanasia. Histomorphometry was performed on sections of the proximal tibia, tibial diaphysis, and vertebral body. The results indicate that 4 to 11 weeks of ovx induced a approximately 44% loss of cancellous bone in the proximal tibia and a approximately 25% loss of cancellous bone in the vertebra with impaired trabecular architecture and high bone turnover. In the intact animals, PTH increased cancellous bone volume to a greater extent in the vertebral body than in the proximal tibia, a site with lower cancellous bone volume at the outset. In the ovx mice, PTH increased cancellous bone volume to a greater extent in the vertebral body, a site displaying moderate cancellous bone loss, than in the proximal tibia, a site with severe cancellous bone loss. Conversely, the treatment added a little cortical bone to the tibia, a highly loaded site, but did not significantly increase cortical width of the vertebral body, a less loaded site. We conclude that, for intermittent PTH treatment to be maximally effective, there must be an adequate number of trabeculae present at the beginning of treatment, regardless of estrogen status. Our results also support an interaction between PTH anabolic action and mechanical loading.
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Affiliation(s)
- H Zhou
- Regional Bone Center, Helen Hayes Hospital, New York State Department of Health, West Haverstraw, NY 10993-1195, USA
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