1
|
Søe K, Delaisse JM, Borggaard XG. Osteoclast formation at the bone marrow/bone surface interface: Importance of structural elements, matrix, and intercellular communication. Semin Cell Dev Biol 2020; 112:8-15. [PMID: 32563679 DOI: 10.1016/j.semcdb.2020.05.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/17/2020] [Accepted: 05/19/2020] [Indexed: 12/28/2022]
Abstract
Osteoclasts, the multinucleated cells responsible for bone resorption, have an enormous destructive power which demands to be kept under tight control. Accordingly, the identification of molecular signals directing osteoclastogenesis and switching on their resorptive activity have received much attention. Mandatory factors were identified, but a very essential aspect of the control mechanism of osteoclastic resorption, i.e. its spatial control, remains poorly understood. Under physiological conditions, multinucleated osteoclasts are only detected on the bone surface, while their mono-nucleated precursors are only in the bone marrow. How are pre-osteoclasts targeted to the bone surface? How is their progressive differentiation coordinated with their approach to the bone surface sites to be resorbed, which is where they finally fuse? Here we review the information on the bone marrow distribution of differentiating pre-osteoclasts relative to the position of the mandatory factors for their differentiation as well as relative to physical entities that may affect their access to the remodelling sites. This info allows recognizing an "osteoclastogenesis route" through the bone marrow and leading to the coincident fusion/resorption site - but also points to what still remains to be clarified regarding this route and regarding the restriction of fusion at the resorption site. Finally, we discuss the mechanism responsible for the start of resorption and its spatial extension. This review underscores that fully understanding the control of bone resorption requires to consider it in both space and time - which demands taking into account the context of bone tissue.
Collapse
Affiliation(s)
- Kent Søe
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
| | - Jean-Marie Delaisse
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
| | - Xenia Goldberg Borggaard
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
| |
Collapse
|
2
|
Wang F, Zhang C, Ge W, Zhang G. Up-regulated CST5 inhibits bone resorption and activation of osteoclasts in rat models of osteoporosis via suppression of the NF-κB pathway. J Cell Mol Med 2019; 23:6744-6754. [PMID: 31402549 PMCID: PMC6787459 DOI: 10.1111/jcmm.14552] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 06/24/2019] [Accepted: 06/30/2019] [Indexed: 12/13/2022] Open
Abstract
Here, we aim at exploring the effect of CST5 on bone resorption and activation of osteoclasts in osteoporosis (OP) rats through the NF‐κB pathway. Microarray analysis was used to screen the OP‐related differentially expressed genes. Osteoporosis was induced in rats by intragastric retinoic acid administration. The serum levels of tartrate‐resistant acid phosphatase (TRAP), bone alkaline phosphatase (BALP) and osteocalcin (OC) and the expression of CD61 on the surface of osteoclasts were examined. The number of osteoclasts and the number and area of resorption pits were detected. Besides, the pathological changes and bone mineral density in bone tissues of rats were assessed. Also, the relationship between CST5 and the NF‐κB pathway was identified through determining the expression of CST5, RANKL, RANK, OPG, p65 and IKB. Poorly expressed CST5 was indicated to affect the OP. CST5 elevation and inhibition of the NF‐κB pathway decreased serum levels of TRAP, BALP and OC and expression of CD61 in vivo and in vitro. In OP rats, CST5 overexpression increased trabecular bones and bone mineral density of bone tissues, but decreased trabecular separation, fat within the bone marrow cavities and the number of osteoclasts through inhibiting the NF‐κB pathway. In vivo experiments showed that CST5 elevation inhibited growth in number and area of osteoclastic resorption pits and restrained osteoclastic bone absorption by inhibiting the NF‐κB pathway. In summary, overexpression of CST5 suppresses the activation and bone resorption of osteoclasts by inhibiting the activation of the NF‐κB pathway.
Collapse
Affiliation(s)
- Fei Wang
- Department of Pain, Linyi People's Hospital, Linyi, China
| | - Chuanzhu Zhang
- Department of Anesthesiology, Linyi People's Hospital, Linyi, China
| | - Wei Ge
- Department of Orthopedics, Chinese Medicine Hospital in Linyi City, Linyi, China
| | - Guoqiang Zhang
- Department of Hand and Foot Surgery, Linyi People's Hospital, Linyi, China
| |
Collapse
|
3
|
Li J, Fukase Y, Shang Y, Zou W, Muñoz-Félix JM, Buitrago L, van Agthoven J, Zhang Y, Hara R, Tanaka Y, Okamoto R, Yasui T, Nakahata T, Imaeda T, Aso K, Zhou Y, Locuson C, Nesic D, Duggan M, Takagi J, Vaughan RD, Walz T, Hodivala-Dilke K, Teitelbaum SL, Arnaout MA, Filizola M, Foley MA, Coller BS. Novel Pure αVβ3 Integrin Antagonists That Do Not Induce Receptor Extension, Prime the Receptor, or Enhance Angiogenesis at Low Concentrations. ACS Pharmacol Transl Sci 2019; 2:387-401. [PMID: 32259072 DOI: 10.1021/acsptsci.9b00041] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Indexed: 01/12/2023]
Abstract
The integrin αVβ3 receptor has been implicated in several important diseases, but no antagonists are approved for human therapy. One possible limitation of current small-molecule antagonists is their ability to induce a major conformational change in the receptor that induces it to adopt a high-affinity ligand-binding state. In response, we used structural inferences from a pure peptide antagonist to design the small-molecule pure antagonists TDI-4161 and TDI-3761. Both compounds inhibit αVβ3-mediated cell adhesion to αVβ3 ligands, but do not induce the conformational change as judged by antibody binding, electron microscopy, X-ray crystallography, and receptor priming studies. Both compounds demonstrated the favorable property of inhibiting bone resorption in vitro, supporting potential value in treating osteoporosis. Neither, however, had the unfavorable property of the αVβ3 antagonist cilengitide of paradoxically enhancing aortic sprout angiogenesis at concentrations below its IC50, which correlates with cilengitide's enhancement of tumor growth in vivo.
Collapse
Affiliation(s)
- Jihong Li
- Allen and Frances Adler Laboratory of Blood and Vascular Biology, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| | - Yoshiyuki Fukase
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Yi Shang
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1677, New York, New York 10029-6574, United States
| | - Wei Zou
- Washington University School of Medicine, Campus Box 8118, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
| | - José M Muñoz-Félix
- Adhesion and Angiogenesis Laboratory, Centre for Tumour Biology, Barts Cancer Institute-a CR-UK Centre of Excellence, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London, EC1M 6BQ, United Kingdom
| | - Lorena Buitrago
- Allen and Frances Adler Laboratory of Blood and Vascular Biology, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| | - Johannes van Agthoven
- Leukocyte Biology and Inflammation and Structural Biology Programs, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, Massachusetts 02129, United States
| | - Yixiao Zhang
- Laboratory of Molecular Electron Microscopy, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| | - Ryoma Hara
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Yuta Tanaka
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Rei Okamoto
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Takeshi Yasui
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Takashi Nakahata
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Toshihiro Imaeda
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Kazuyoshi Aso
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Yuchen Zhou
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1677, New York, New York 10029-6574, United States
| | - Charles Locuson
- Agios Pharmaceuticals, 88 Sidney Street, Cambridge, Massachusetts 02139-4169, United States
| | - Dragana Nesic
- Allen and Frances Adler Laboratory of Blood and Vascular Biology, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| | - Mark Duggan
- LifeSci Consulting, LLC, 18243 SE Ridgeview Drive, Tequesta, Florida 33469, United States
| | - Junichi Takagi
- Laboratory of Protein Synthesis and Expression, Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Roger D Vaughan
- Rockefeller University Center for Clinical and Translational Science, Rockefeller University, 2130 York Avenue, New York, New York 10065, United States
| | - Thomas Walz
- Laboratory of Molecular Electron Microscopy, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| | - Kairbaan Hodivala-Dilke
- Adhesion and Angiogenesis Laboratory, Centre for Tumour Biology, Barts Cancer Institute-a CR-UK Centre of Excellence, Queen Mary University of London, John Vane Science Centre, Charterhouse Square, London, EC1M 6BQ, United Kingdom
| | - Steven L Teitelbaum
- Washington University School of Medicine, Campus Box 8118, 660 South Euclid Avenue, St. Louis, Missouri 63110, United States
| | - M Amin Arnaout
- Leukocyte Biology and Inflammation and Structural Biology Programs, Division of Nephrology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, Massachusetts 02129, United States
| | - Marta Filizola
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1677, New York, New York 10029-6574, United States
| | - Michael A Foley
- Tri-Institutional Therapeutics Discovery Institute, 413 East 69 Street, New York, New York 10021, United States
| | - Barry S Coller
- Allen and Frances Adler Laboratory of Blood and Vascular Biology, Rockefeller University, 1230 York Avenue, New York, New York 10065, United States
| |
Collapse
|
4
|
Bergsma A, Ganguly SS, Wiegand ME, Dick D, Williams BO, Miranti CK. Regulation of cytoskeleton and adhesion signaling in osteoclasts by tetraspanin CD82. Bone Rep 2019; 10:100196. [PMID: 30788390 PMCID: PMC6369370 DOI: 10.1016/j.bonr.2019.100196] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 01/18/2019] [Accepted: 01/28/2019] [Indexed: 12/11/2022] Open
Abstract
We used a myeloid-specific Cre to conditionally delete CD82 in mouse osteoclasts and their precursors. In contrast to global loss of CD82 (gKO), conditional loss of CD82 (cKO) in osteoclasts does not affect cortical bone, osteoblasts, or adipocytes. CD82 loss results in greater trabecular volume and trabecular number but reduced trabecular space in 6-month old male mice. Though this trend is present in females it did not reach significance; whereas there was an increase in osteoclast numbers and eroded surface area only in female cKO mice. In vitro, there is an increase in osteoclast fusion and defects in actin assembly in both gKO and cKO mice, irrespective of sex. This is accompanied by altered osteoclast morphology and decreased release of CTX in vitro. Integrin αvβ3 expression is reduced, while integrin β1 is increased. Signaling to Src, Syk, and Vav are also compromised. We further discovered that expression of Clec2 and its ligand, Podoplanin, molecules that also signal to Syk and Vav, are increased in differentiated osteoclasts. Loss of CD82 reduces their expression. Thus, CD82 is required for correct assembly of the cytoskeleton and to limit osteoclast fusion, both needed for normal osteoclast function.
Collapse
Affiliation(s)
- Alexis Bergsma
- Center for Cancer and Cell Biology, Program for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Sourik S Ganguly
- Center for Cancer and Cell Biology, Program for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA.,Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Mollie E Wiegand
- Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ, USA
| | - Daniel Dick
- Center for Cancer and Cell Biology, Program for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Bart O Williams
- Center for Cancer and Cell Biology, Program for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Cindy K Miranti
- Center for Cancer and Cell Biology, Program for Skeletal Disease and Tumor Microenvironment, Van Andel Research Institute, Grand Rapids, MI, USA.,Department of Cellular and Molecular Medicine, University of Arizona Cancer Center, University of Arizona, Tucson, AZ, USA
| |
Collapse
|
5
|
A novel miR17/protein tyrosine phosphatase-oc/EphA4 regulatory axis of osteoclast activity. Arch Biochem Biophys 2018; 650:30-38. [PMID: 29763590 PMCID: PMC5985224 DOI: 10.1016/j.abb.2018.05.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 05/08/2018] [Accepted: 05/11/2018] [Indexed: 12/17/2022]
Abstract
Information about the molecular mechanisms leading to the activation of the osteoclast is relatively limited. While there is compelling evidence that the signaling mechanisms of Src and integrin β3 are essential for osteoclast activation, the regulation of these two signaling mechanisms is not fully understood. In this review, evidence supporting a novel regulatory axis of osteoclast activation that plays an upstream regulatory role in both the Src and integrin β3 signaling during osteoclast activation is discussed. This regulatory axis contains three unique components: a structurally unique transmembrane protein-tyrosine phosphatase, PTP-oc, EphA4, and miR17. In the first component, PTP-oc activates the Src signaling through dephosphorylation of the inhibitory tyr-527 of Src. This in turn activates the integrin β3 signaling, enhances the JNK2/NFκB signaling, promotes the ITAM/Syk signaling, and suppresses the ITIM/Shp1 signaling; the consequence of which is activation of the osteoclast. In the second component, EphA4 inhibits osteoclast activity by suppressing the integrin β3 signaling. PTP-oc relieves the suppressive actions of EphA4 by directly dephosphorylating EphA4. In the third component, PTP-oc expression is negatively regulated by miR17. Accordingly, suppression of miR17 during osteoclast activation upregulates the PTP-oc signaling and suppresses the EphA4 signaling, resulting in the activation of the osteoclast. This regulatory axis is unique, in that each of the three components acts to exert suppressive action on their respective immediate downstream inhibitory step. Because the final downstream event is the EphA4-mediated inhibition of osteoclast activation, the overall effect of this mechanism is the stimulation of osteoclast activity.
Collapse
|
6
|
Nurden AT. Should studies on Glanzmann thrombasthenia not be telling us more about cardiovascular disease and other major illnesses? Blood Rev 2017; 31:287-299. [PMID: 28395882 DOI: 10.1016/j.blre.2017.03.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/23/2017] [Indexed: 12/17/2022]
Abstract
Glanzmann thrombasthenia (GT) is a rare inherited bleeding disorder caused by loss of αIIbβ3 integrin function in platelets. Most genetic variants of β3 also affect the widely expressed αvβ3 integrin. With brief mention of mouse models, I now look at the consequences of disease-causing ITGA2B and ITGB3 mutations on the non-hemostatic functions of platelets and other cells. Reports of arterial thrombosis in GT patients are rare, but other aspects of cardiovascular disease do occur including deep vein thrombosis and congenital heart defects. Thrombophilic and other risk factors for thrombosis and lessons from heterozygotes and variant forms of GT are discussed. Assessed for GT patients are reports of leukemia and cancer, loss of fertility, bone pathology, inflammation and wound repair, infections, kidney disease, autism and respiratory disease. This survey shows an urgent need for a concerted international effort to better determine how loss of αIIbβ3 and αvβ3 influences health and disease.
Collapse
Affiliation(s)
- Alan T Nurden
- Institut de Rhythmologie et de Modélisation Cardiaque, Plateforme Technologique d'Innovation Biomédicale, Hôpital Xavier Arnozan, Pessac, France.
| |
Collapse
|
7
|
Abstract
Bone metastasis is a common burden in many types of cancer and has a severe impact on the quality of life in patients. Hence, specific therapeutic strategies inhibiting tumor induced osteolysis are urgently needed. In this study, we aimed to interfere with integrin adhesion receptors, which are central players of the bone resorption process. For this purpose, we used cilengitide, a cyclic RGD peptide, which blocks integrin αVβ3 and αVβ5-ligand binding. Our results revealed that cilengitide blocked osteoclast maturation in a dose-dependent manner. In detail, pre-osteoclasts treated with cilengitide exhibited reduced cell spreading, cell migration and cell adhesion on RGD-containing matrix proteins, which are ligands of integrin αV. The activation of the most upstream signal transduction molecules of the integrin receptor-initiated pathway, FAK and c-Src, were consistently blocked by cilengitide. First evidence suggests that cilengitide might interfere with metastatic bone disease in vivo and this study describes a potential underlying mechanism of the inhibitory effect of cilengitide on αV-integrin expressing pre-osteoclasts by blocking integrin ligand binding and interfering with osteoclast maturation and cell behavior. In conclusion, our findings suggest that cilengitide, which interferes with αV-integrins on osteoclasts, may represent a novel therapeutic strategy in the treatment of malignant bone disease.
Collapse
|
8
|
Docheva D, Popov C, Alberton P, Aszodi A. Integrin signaling in skeletal development and function. ACTA ACUST UNITED AC 2014; 102:13-36. [DOI: 10.1002/bdrc.21059] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 01/14/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Denitsa Docheva
- Experimental Surgery and Regenerative Medicine, Department of Surgery; Ludwig-Maximilians-University; 80336 Munich Germany
| | - Cvetan Popov
- Experimental Surgery and Regenerative Medicine, Department of Surgery; Ludwig-Maximilians-University; 80336 Munich Germany
| | - Paolo Alberton
- Experimental Surgery and Regenerative Medicine, Department of Surgery; Ludwig-Maximilians-University; 80336 Munich Germany
| | - Attila Aszodi
- Experimental Surgery and Regenerative Medicine, Department of Surgery; Ludwig-Maximilians-University; 80336 Munich Germany
| |
Collapse
|
9
|
Abstract
Although much is known about how osteoclasts are formed, we know little about how they are activated, or how they recognize bone as the substrate appropriate for resorption. Bone mineral is considered to be essential to this recognition process, but a "mineral receptor" has never been identified. Recently, we found that resorptive behavior, as judged by the formation of ruffled borders and actin rings, occurs on ordinary tissue culture substrates if they are first coated with vitronectin. Similarly, vitronectin-coated substrates induce osteoclasts to secrete tartrate-resistant acid phosphatase and to form podosome belts, and to make resorption trails in the protein that coat the substrate. The same applies to bone mineral, which only induces resorptive behavior if coated with vitronectin. In contrast, fibronectin has none of these effects, despite inducing adhesion and spreading. It appears that osteoclasts recognize bone as the substrate appropriate for resorption through the high affinity of vitronectin-receptor ligands for bone mineral.
Collapse
Affiliation(s)
- T J Chambers
- Department of Cellular Pathology, St George's University of London, London, United Kingdom.
| | | |
Collapse
|
10
|
Nurden A, Nurden P. Advances in our understanding of the molecular basis of disorders of platelet function. J Thromb Haemost 2011; 9 Suppl 1:76-91. [PMID: 21781244 DOI: 10.1111/j.1538-7836.2011.04274.x] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Genetic defects of platelet function give rise to mucocutaneous bleeding of varying severity because platelets fail to fulfil their haemostatic role after vessel injury. Abnormalities of pathways involving glycoprotein (GP) mediators of adhesion (Bernard-Soulier syndrome, platelet-type von Willebrand disease) and aggregation (Glanzmann thrombasthenia) are the most studied and affect the GPIb-IX-V complex and integrin αIIbβ3, respectively. Leukocyte adhesion deficiency-III combines Glanzmann thrombasthenia with infections and defects of kindlin-3, a mediator of integrin activation. Agonist-specific deficiencies in platelet aggregation relate to mutations of primary receptors for ADP (P2Y(12)), thromboxane A(2) (TXA2R) and collagen (GPVI); however, selective abnormalities of intracellular signalling pathways remain better understood in mouse models. Defects of secretion from δ-granules are accompanied by pigment defects in the Hermansky-Pudlak and Chediak-Higashi syndromes; they concern multiple genes and protein complexes involved in secretory organelle biogenesis and function. Quebec syndrome is linked to a tandem duplication of the urokinase plasminogen activator (PLAU) gene while locus assignment to chromosome 3p has advanced the search for the gene(s) responsible for α-granule deficiency in the gray platelet syndrome. Defects of α-granule biosynthesis also involve germline VPS33B mutations in the ARC (arthrogryposis, renal dysfunction and cholestasis) syndrome. A mutation in transmembrane protein 16F (TMEM16F) has been linked to a defective procoagulant activity and phosphatidylserine expression in the Scott syndrome. Cytoskeletal dysfunction (with platelet anisotrophy) occurs not only in the Wiskott-Aldrich syndrome but also in filamin A deficiency or MYH9-related disease while GATA1 mutations or RUNX1 haploinsufficiency can affect expression of multiple platelet proteins.
Collapse
Affiliation(s)
- A Nurden
- Centre de Référence des Pathologies Plaquettaires, Plateforme Technologique d'Innovation Biomédicale, Hôpital Xavier Arnozan, Pessac, France.
| | | |
Collapse
|
11
|
Nurden AT, Fiore M, Nurden P, Heilig R, Pillois X. Are bone defects in rare patients with Glanzmann's thrombasthenia associated with ITGB3 or ITGA2B mutations? Platelets 2011; 22:547-51. [PMID: 21557682 DOI: 10.3109/09537104.2011.573600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The question as to whether Glanzmann thrombasthenia patients with ITGB3 defects and deficiencies of both αIIbβ3 and αvβ3 show phenotypic differences to those with abnormalities exclusive to αIIbβ3 is unresolved. Studies on β3-deficient mice have shown an increased bone mass. Here we review the literature on bone defects in thrombasthenia patients and report the molecular analysis of a patient associating a lifelong thrombasthenia-like syndrome with skeletal defects. We show that the patient is compound heterozygote for Arg327His and Gly391Arg mutations in αIIb, with one mutation inherited from each parent. Modelling strongly suggested that both mutations act by destabilizing the αIIb beta propeller. So it appears likely that this patient has a combination of co-expressed genetic defects.
Collapse
Affiliation(s)
- Alan T Nurden
- Centre de Référence des Pathologies Plaquettaires, Plateforme Technologique et d'Innovation Biomédicale, Hôpital Xavier Arnozan, Pessac, France.
| | | | | | | | | |
Collapse
|
12
|
Blair HC, Robinson LJ, Huang CLH, Sun L, Friedman PA, Schlesinger PH, Zaidi M. Calcium and bone disease. Biofactors 2011; 37:159-67. [PMID: 21674636 PMCID: PMC3608212 DOI: 10.1002/biof.143] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 12/18/2010] [Indexed: 11/12/2022]
Abstract
Calcium transport and calcium signaling are of basic importance in bone cells. Bone is the major store of calcium and a key regulatory organ for calcium homeostasis. Bone, in major part, responds to calcium-dependent signals from the parathyroids and via vitamin D metabolites, although bone retains direct response to extracellular calcium if parathyroid regulation is lost. Improved understanding of calcium transporters and calcium-regulated cellular processes has resulted from analysis of genetic defects, including several defects with low or high bone mass. Osteoblasts deposit calcium by mechanisms including phosphate and calcium transport with alkalinization to absorb acid created by mineral deposition; cartilage calcium mineralization occurs by passive diffusion and phosphate production. Calcium mobilization by osteoclasts is mediated by acid secretion. Both bone forming and bone resorbing cells use calcium signals as regulators of differentiation and activity. This has been studied in more detail in osteoclasts, where both osteoclast differentiation and motility are regulated by calcium.
Collapse
Affiliation(s)
- Harry C Blair
- Department of Pathology, University of Pittsburgh, Veterans Affairs Health System, PA, USA.
| | | | | | | | | | | | | |
Collapse
|
13
|
Novack DV, Faccio R. Osteoclast motility: putting the brakes on bone resorption. Ageing Res Rev 2011; 10:54-61. [PMID: 19788940 PMCID: PMC2888603 DOI: 10.1016/j.arr.2009.09.005] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 09/23/2009] [Accepted: 09/23/2009] [Indexed: 11/28/2022]
Abstract
As the skeleton ages, the balanced formation and resorption of normal bone remodeling is lost, and bone loss predominates. The osteoclast is the specialized cell that is responsible for bone resorption. It is a highly polarized cell that must adhere to the bone surface and migrate along it while resorbing, and cytoskeletal reorganization is critical. Podosomes, highly dynamic actin structures, mediate osteoclast motility. Resorbing osteoclasts form a related actin complex, the sealing zone, which provides the boundary for the resorptive microenvironment. Similar to podosomes, the sealing zone rearranges itself to allow continuous resorption while the cell is moving. The major adhesive protein controlling the cytoskeleton is αvβ3 integrin, which collaborates with the growth factor M-CSF and the ITAM receptor DAP12. In this review, we discuss the signaling complexes assembled by these molecules at the membrane, and their downstream mediators that control OC motility and function via the cytoskeleton.
Collapse
|
14
|
Abstract
Integrins are adhesive proteins that have evolved to mediate cell-cell and cell-matrix communication that is indispensable for development and postnatal physiology. Despite their widespread expression, the genetic deletion of specific integrin family members in lower organisms as well as mammals leads to relatively distinct abnormalities. Many of the processes in which integrins participate have a requirement for strong adhesion coincident with times of mechanical stress. In Drosophila, the absence of specific integrins leads to detachment of muscle from the gut and body wall and separation of the two epithelial layers in the wing. In mice and humans, a deletion of either subunit of the laminin-binding integrin, α6β4 leads to severe skin blistering and defects in other epithelial layers. In addition, integrins have also evolved to serve more subspecialized roles ranging from the establishment of a stem cell niche in Drosophila and mammals, to the regulation of pathogenic tumor vascularization, platelet adhesion, and leukocyte transmigration in mammalian systems. However, some cells seem to function normally in the absence of all integrins, as revealed by the very surprising finding that deletion of all the major integrin types on dendritic cells of mice has no effect on the ability of these cells to migrate within the interstitium of the skin and enter into lymphatics. In addition to serving as transmembrane mechanical links, integrins in vertebrates synergize with a number of receptors including growth factor receptors, to enhance responses. This leads to the activation of a large signaling network that affects cell proliferation and differentiation, as well as cell shape and migration. In vivo studies, in lower organisms, knockout mouse models as well as in inherited human diseases together have provided important insights into how this major, primordial family of adhesion receptors have remained true to their name "integrins" as their diverse functions have in common the ability to integrate extracellular stimuli into intracellular signals that affect cell behavior.
Collapse
|
15
|
Abstract
In vitro differentiated monocytes were used to characterize the cellular defect in a type of osteopetrosis with minimally functional osteoclasts, in which defects associated with common causes of osteopetrosis were excluded by gene sequencing. Monocytes from the blood of a 28-year-old patient were differentiated in media with RANKL and CSF-1. Cell fusion, acid compartments within cells, and tartrate resistant acid phosphatase (TRAP) activity were normal. However, the osteoclasts made abnormally small pits on the dentine. Phalloidin labeling showed that the cell attachments lacked the peripheral ring structure that supports lacunar resorption. Instead, the osteoclasts had clusters of podosomes near the center of cell attachments. Antibody to the alphavbeta3 integrin pair or to the C-terminal of beta3 did not label podosomes, but antibody to alphav labeled them. Western blots using antibody to the N-terminal of beta3 showed a protein of reduced size. Integrins beta1 and beta5 were upregulated, but, in contrast to observations in beta3 defects, alpha2 had not increased. The rho-GTP exchange protein Vav3, a key attachment organizing protein, did not localize normally with peripheral attachment structures. Vav3 forms of 70 kD and 90 kD were identified on western blots. However, the proteins beta3 integrin, Vav3, Plekhm1, and Src, implicated in attachment defects, had normal exon sequences. In this new type of osteopetrosis, the integrin-organizing complex is dysfunctional, and at least two attachment proteins may be partially degraded.
Collapse
|
16
|
Deletion of β1 Integrins from Cortical Osteocytes Reduces Load-Induced Bone Formation. Cell Mol Bioeng 2009. [DOI: 10.1007/s12195-009-0068-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
17
|
Advances in osteoclast biology resulting from the study of osteopetrotic mutations. Hum Genet 2008; 124:561-77. [DOI: 10.1007/s00439-008-0583-8] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Accepted: 10/28/2008] [Indexed: 02/05/2023]
|
18
|
Abstract
Bone is a dynamic organ constantly remodeled to support calcium homeostasis and structural needs. The osteoclast is the cell responsible for removing both the organic and inorganic components of bone. It is derived from hematopoietic progenitors in the macrophage lineage and differentiates in response to the tumor necrosis factor family cytokine receptor activator of NF kappa B ligand. alpha v beta 3 integrin mediates cell adhesion necessary for polarization and formation of an isolated, acidified resorptive microenvironment. Defects in osteoclast function, whether genetic or iatrogenic, may increase bone mass but lead to poor bone quality and a high fracture risk. Pathological stimulation of osteoclast formation and resorption occurs in postmenopausal osteoporosis, inflammatory arthritis, and metastasis of tumors to bone. In these diseases, osteoclast activity causes bone loss that leads to pain, deformity, and fracture. Thus, osteoclasts are critical for normal bone function, but their activity must be controlled.
Collapse
Affiliation(s)
- Deborah V Novack
- Department of Pathology and Immunology, Division of Bone and Mineral Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | |
Collapse
|
19
|
Sheng MHC, Wergedal JE, Mohan S, Lau KHW. Osteoactivin is a novel osteoclastic protein and plays a key role in osteoclast differentiation and activity. FEBS Lett 2008; 582:1451-8. [PMID: 18381073 DOI: 10.1016/j.febslet.2008.03.030] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 03/18/2008] [Accepted: 03/20/2008] [Indexed: 01/22/2023]
Abstract
This study presents gene expression, protein expression, and in situ immunohistochemical evidence that osteoclasts express high levels of osteoactivin (OA), which had previously been reported to be an osteoblast-specific protein in bone. OA expression in osteoclasts was up-regulated upon receptor activator of NFkappaB ligand-induced differentiation. Suppression of functional activity of OA with neutralizing antibody reduced cell size, number of nuclei, fusion, and bone resorption activity of osteoclasts. OA was co-immunoprecipitated with integrin beta3 and beta1, indicating that OA co-localizes with integrin beta3 and/or beta1 in a hetero-polymeric complex in osteoclasts. These findings indicate that OA is a novel osteoclastic protein and plays a role in osteoclast differentiation and/or activity.
Collapse
Affiliation(s)
- Matilda H-C Sheng
- Musculoskeletal Disease Center (151), Jerry L. Pettis Memorial VA Medical Center, Loma Linda, CA 92357, USA.
| | | | | | | |
Collapse
|
20
|
Globus RK. Extracellular Matrix and Integrin Interactions in the Skeletal Responses to Mechanical Loading and Unloading. Clin Rev Bone Miner Metab 2007. [DOI: 10.1007/s12018-008-9013-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
21
|
Muzylak M, Arnett TR, Price JS, Horton MA. The in vitro effect of pH on osteoclasts and bone resorption in the cat: implications for the pathogenesis of FORL. J Cell Physiol 2007; 213:144-50. [PMID: 17477347 PMCID: PMC7167146 DOI: 10.1002/jcp.21103] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Dental disease due to osteoclast over‐activity reaches epidemic proportions in older domestic cats and has also been reported in wild cats. Feline osteoclastic resorptive lesions (FORL) involve extensive resorption of the tooth leaving it liable to root fracture and subsequent tooth loss. The aetio‐pathogenesis of FORL is not known. Recent work has shown that systemic acidosis causes increased osteoclast activation and that loci of infection or inflammation in cat mouth are likely to be acidotic. To investigate this, we generated osteoclasts from cat blood and found that they formed in large numbers (∼400) in cultures on bovine cortical bone slices. Acidosis caused an increase in the size of cells—in cultures maintained up to 14 days at basal pH 7.25, mean osteoclast area was 0.01 ± 0.003 mm2, whereas an 8.6‐fold increase was observed in cells cultured between 11 and 14 days at pH 7.15 (0.086 ± 0.004 mm2). Acidosis caused a modest increase in the number of osteoclasts. Exposure to pH 6.92 exhibited a 5‐fold increase in the area of bone slices covered by resorption lacunae (∼70% bone slice resorbed). In line with this finding, significant increases were observed in the expression of cathepsin K and proton pump enzymes (both approximately 3‐fold) that are key enzymes reflective of resorptive activity in osteoclasts. These results demonstrate that acidosis is a major regulator of osteoclast formation and functional activation in the cat, and suggest that local pH changes may play a significant role in the pathogenesis of FORL. J. Cell. Physiol. 213: 144–150, 2007. © 2007 Wiley‐Liss, Inc.
Collapse
Affiliation(s)
- Mariusz Muzylak
- Department of Veterinary Basic Sciences, The Royal Veterinary College, London, UK
| | | | - Joanna S. Price
- Department of Veterinary Basic Sciences, The Royal Veterinary College, London, UK
| | - Michael A. Horton
- Department of Medicine, Rayne Building, University College London, London, UK
| |
Collapse
|
22
|
Armstrong VJ, Muzylak M, Sunters A, Zaman G, Saxon LK, Price JS, Lanyon LE. Wnt/beta-catenin signaling is a component of osteoblastic bone cell early responses to load-bearing and requires estrogen receptor alpha. J Biol Chem 2007; 282:20715-27. [PMID: 17491024 DOI: 10.1074/jbc.m703224200] [Citation(s) in RCA: 230] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The Wnt/beta-catenin pathway has been implicated in bone cell response to their mechanical environment. This response is the origin of the mechanism by which bone cells adjust bone architecture to maintain bone strength. Osteoporosis is the most widespread failure of this mechanism. The degree of osteoporotic bone loss in men and women is related to bio-available estrogen. Here we report that in osteoblastic ROS 17/2.8 cells and primary osteoblast cultures, a single short period of dynamic mechanical strain, as well as the glycogen synthase kinase-3beta (GSK-3beta) inhibitor LiCl, increased nuclear accumulation of activated beta-catenin and stimulated TCF/LEF reporter activity. This effect was blocked by the estrogen receptor (ER) modulators ICI 182,780 and tamoxifen and was absent in primary osteoblast cultures from mice lacking ERalpha. Microarray expression data for 25,000 genes from total RNA extracted from tibiae of wild-type mice within 24 h of being loaded in vivo showed differential gene regulation between loaded and contralateral non-loaded bones of 10 genes established to be involved in the Wnt pathway. Only 2 genes were involved in loaded tibiae from mice lacking ERalpha (ERalpha(-/-)). Together these data suggest that Wnt/beta-catenin signaling contributes to bone cell early responses to mechanical strain and that its effectiveness requires ERalpha. Reduced effectiveness of bone cell responses to bone loading, associated with estrogen-related decline in ERalpha, may contribute to the failure to maintain structurally appropriate bone mass in osteoporosis in both men and women.
Collapse
Affiliation(s)
- Victoria J Armstrong
- Department of Veterinary Basic Sciences, The Royal Veterinary College, Royal College Street, London, United Kingdom
| | | | | | | | | | | | | |
Collapse
|
23
|
Komano Y, Nanki T, Hayashida K, Taniguchi K, Miyasaka N. Identification of a human peripheral blood monocyte subset that differentiates into osteoclasts. Arthritis Res Ther 2007; 8:R152. [PMID: 16987426 PMCID: PMC1779441 DOI: 10.1186/ar2046] [Citation(s) in RCA: 110] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Revised: 08/25/2006] [Accepted: 09/21/2006] [Indexed: 11/10/2022] Open
Abstract
Increased bone resorption mediated by osteoclasts causes various diseases such as osteoporosis and bone erosion in rheumatoid arthritis (RA). Osteoclasts are derived from the monocyte/macrophage lineage, but the precise origin remains unclear. In the present study, we show that the purified CD16- human peripheral blood monocyte subset, but not the CD16+ monocyte subset, differentiates into osteoclast by stimulation with receptor activator of NF-κB ligand (RANKL) in combination with macrophage colony-stimulating factor (M-CSF). Integrin-β3 mRNA and the integrin-αvβ3 heterodimer were only expressed on CD16- monocytes, when they were stimulated with RANKL + M-CSF. Downregulation of β3-subunit expression by small interfering RNA targeting β3 abrogated osteoclastogenesis from the CD16- monocyte subset. In contrast, the CD16+ monocyte subset expressed larger amounts of tumor necrosis factor alpha and IL-6 than the CD16- subset, which was further enhanced by RANKL stimulation. Examination of RA synovial tissue showed accumulation of both CD16+ and CD16- macrophages. Our results suggest that peripheral blood monocytes consist of two functionally heterogeneous subsets with distinct responses to RANKL. Osteoclasts seem to originate from CD16- monocytes, and integrin β3 is necessary for osteoclastogenesis. Blockade of accumulation and activation of CD16- monocytes could therefore be a beneficial approach as an anti-bone resorptive therapy, especially for RA.
Collapse
MESH Headings
- Adaptor Proteins, Signal Transducing
- Antigens, CD/metabolism
- Arthritis, Rheumatoid/complications
- Arthritis, Rheumatoid/immunology
- Arthritis, Rheumatoid/pathology
- Cell Differentiation/drug effects
- Cells, Cultured
- Extracellular Signal-Regulated MAP Kinases/metabolism
- GPI-Linked Proteins
- Humans
- Integrin beta3/genetics
- Integrin beta3/metabolism
- Integrins/metabolism
- Interleukin-6/metabolism
- Macrophage Colony-Stimulating Factor/pharmacology
- Membrane Proteins
- Monocytes/classification
- Monocytes/cytology
- Monocytes/metabolism
- NF-kappa B/genetics
- NFATC Transcription Factors/genetics
- Osteoclasts/cytology
- Osteoporosis/complications
- Osteoporosis/immunology
- Osteoporosis/pathology
- Peptides, Cyclic/pharmacology
- RANK Ligand/pharmacology
- RNA, Small Interfering
- Receptor, Macrophage Colony-Stimulating Factor/genetics
- Receptors, Cell Surface/genetics
- Receptors, IgG/metabolism
- Receptors, Immunologic/genetics
- Receptors, Vitronectin/metabolism
- Synovial Membrane/immunology
- Synovial Membrane/pathology
- TNF Receptor-Associated Factor 6/genetics
- Tumor Necrosis Factor-alpha/metabolism
- p38 Mitogen-Activated Protein Kinases/metabolism
Collapse
Affiliation(s)
- Yukiko Komano
- Department of Medicine and Rheumatology, Graduate School, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
- The 21st Century Center of Excellence Program for the Frontier Research on Molecular Destruction and Reconstruction of Tooth and Bone, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| | - Toshihiro Nanki
- Department of Medicine and Rheumatology, Graduate School, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| | - Kenji Hayashida
- Department of Orthopedic Surgery, Hoshigaoka Koseinenkin Hospital, Osaka 573-8511, Japan
| | - Ken Taniguchi
- Division of Rheumatic Diseases, Tokyo Metropolitan Bokutoh Hospital, Tokyo 130-0022, Japan
| | - Nobuyuki Miyasaka
- Department of Medicine and Rheumatology, Graduate School, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
- The 21st Century Center of Excellence Program for the Frontier Research on Molecular Destruction and Reconstruction of Tooth and Bone, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
| |
Collapse
|
24
|
Muzylak M, Price JS, Horton MA. Hypoxia induces giant osteoclast formation and extensive bone resorption in the cat. Calcif Tissue Int 2006; 79:301-9. [PMID: 17048066 DOI: 10.1007/s00223-006-0082-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Accepted: 07/04/2006] [Indexed: 02/07/2023]
Abstract
Dental disease due to osteoclast (OC) overactivity reaches epidemic proportions in older domestic cats and has also been reported in wild cats. Feline odontoclastic resorptive lesions (FORL) involve extensive resorption of the tooth, leaving it liable to root fracture and subsequent loss. The etiopathogenesis of FORL remains unclear. Here, we explore the hypothesis that FORL is associated with hypoxia in the oral microenvironment, leading to increased OC activity. To investigate this, we developed a method of generating OCs from cat blood. Reducing O2 from 20% to 2% increased the mean area of OC eightfold from 0.01 to 0.08 mm2. In hypoxic cultures, very large OCs containing several hundred nuclei were evident (reaching a maximum size of approximately 14 mm2). Cultures exposed to 2% O2 exhibited an increase of approximately 13-fold in the area of bone slices covered by resorption lacunae. In line with this finding, there was a significant increase in cells differentiating under hypoxic conditions, reflected in increased expression of cathepsin K and proton pump enzymes. In conclusion, these results demonstrate that oxygen tension is a major regulator of OC formation in the cat. However, in this species, hypoxia induces the formation of "giant" OCs, which can be so large as to be visible with the naked eye and yet also actively resorb. This suggests that local hypoxia is likely to play a key role in the pathogenesis of FORL and other inflammatory conditions that are associated with bone resorption in cats.
Collapse
Affiliation(s)
- M Muzylak
- Department of Veterinary Basic Sciences, The Royal Veterinary College, Royal College Street, London, NW1 OTU, UK
| | | | | |
Collapse
|
25
|
Abstract
Glanzmann thrombasthenia (GT) is a rare autosomal recessive bleeding syndrome affecting the megakaryocyte lineage and characterized by lack of platelet aggregation. The molecular basis is linked to quantitative and/or qualitative abnormalities of alphaIIb beta3 integrin. This receptor mediates the binding of adhesive proteins that attach aggregating platelets and ensure thrombus formation at sites of injury in blood vessels. GT is associated with clinical variability: some patients have only minimal bruising while others have frequent, severe and potentially fatal hemorrhages. The site of bleeding in GT is clearly defined: purpura, epistaxis, gingival hemorrhage, and menorrhagia are nearly constant features; gastrointestinal bleeding and hematuria are less common. In most cases, bleeding symptoms manifest rapidly after birth, even if GT is occasionally only diagnosed in later life. Diagnosis should be suspected in patients with mucocutaneous bleeding with absent platelet aggregation in response to all physiologic stimuli, and a normal platelet count and morphology. Platelet alphaIIb beta3 deficiency or nonfunction should always be confirmed, for example by flow cytometry. In order to avoid platelet alloimmunisation, therapeutic management must include, if possible, local hemostatic procedures and/or desmopressin (DDAVP) administration. Transfusion of HLA-compatible platelet concentrates may be necessary if these measures are ineffective, or to prevent bleeding during surgery. Administration of recombinant factor VIIa is an increasingly used therapeutic alternative. GT can be a severe hemorrhagic disease, however the prognosis is excellent with careful supportive care.
Collapse
Affiliation(s)
- Alan T Nurden
- IFR No4/CRPP, Laboratoire d'Hématologie, Hôpital Cardiologique, 33604 Pessac, France.
| |
Collapse
|
26
|
Ross FP, Teitelbaum SL. alphavbeta3 and macrophage colony-stimulating factor: partners in osteoclast biology. Immunol Rev 2005; 208:88-105. [PMID: 16313343 DOI: 10.1111/j.0105-2896.2005.00331.x] [Citation(s) in RCA: 239] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Osteoclasts, the sole bone-resorbing cells, arise by fusion and differentiation of monocyte/macrophage precursors. Matrix degradation requires adhesion of the osteoclast to bone, an integrin alphavbeta3-mediated event that also stimulates signals which polarize the cell and secrete resorptive molecules such as hydrochloric acid and acidic proteases. Two cytokines are necessary and sufficient for osteoclastogenesis, receptor activator of nuclear factor kappaB ligand (RANKL) and macrophage colony-stimulating factor (M-CSF), both produced by mesenchymal cells in the bone marrow environment. M-CSF promotes survival and proliferation of osteoclast precursors. It also contributes to their differentiation and regulates the cytoskeletal changes that accompany bone resorption. Binding of M-CSF to c-Fms, its receptor, recruits adapter proteins and cytosolic kinases, thereby activating a variety of intracellular signals. We herein review how alphavbeta3 and M-CSF, alone and in concert, impact production, survival, and function of the osteoclast, thereby controlling skeletal mass. Signals from alphavbeta3 and/or c-Fms activate Syk and Vav3, originally defined by their function in lymphoid cells. Genetic depletion of either protein generates a strong bone phenotype, underscoring the promise of osteoimmunobiology.
Collapse
Affiliation(s)
- F Patrick Ross
- Washington University School of Medicine, St. Louis, MO 63110, USA.
| | | |
Collapse
|
27
|
Balemans W, Van Wesenbeeck L, Van Hul W. A clinical and molecular overview of the human osteopetroses. Calcif Tissue Int 2005; 77:263-74. [PMID: 16307387 DOI: 10.1007/s00223-005-0027-6] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2005] [Accepted: 04/08/2005] [Indexed: 12/15/2022]
Abstract
The osteopetroses are a heterogeneous group of bone remodeling disorders characterized by an increase in bone density due to a defect in osteoclastic bone resorption. In humans, several types can be distinguished and a classification has been made based on their mode of inheritance, age of onset, severity, and associated clinical symptoms. The best-known forms of osteopetrosis are the malignant and intermediate autosomal recessive forms and the milder autosomal dominant subtypes. In addition to these forms, a restricted number of cases have been reported in which additional clinical features unrelated to the increased bone mass occur. During the last years, molecular genetic studies have resulted in the identification of several disease-causing gene mutations. Thus far, all genes associated with a human osteopetrosis encode proteins that participate in the functioning of the differentiated osteoclast. This contributed substantially to the understanding of osteoclast functioning and the pathogenesis of the human osteopetroses and will provide deeper insights into the molecular pathways involved in other bone pathologies, including osteoporosis.
Collapse
Affiliation(s)
- W Balemans
- Department of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium
| | | | | |
Collapse
|
28
|
Abstract
The osteoclast is a monocyte-derived cell with complex regulatory control due to its role, balancing calcium homeostasis with skeletal modelling and repair. Normal differentiation requires tyrosine kinase- and tumor necrosis-family receptors, normally fms and RANK. Ligands for these receptors plus unidentified serum or cell-presented factor(s) are needed for in vitro differentiation, possibly signalling via an immune-like tyrosine kinase acceptor molecule. Osteoclast development and activity are increased by cytokines signalling through GP130, such as IL-6, by TGF-beta, and by IL-1, although these cannot replace serum. Other tyrosine kinase receptors including kit and met can augment fms signalling, and TNFs other than RANKL, including TNFalpha and TRAIL, modify RANK signalling, which is also susceptible to interference by interferons. The situation is further complicated by G-protein coupled receptors including the calcitonin receptor, by integrin or calcium-mediated signals, and by estrogen receptors, which operate in bone largely via NO downstream signals. Differentiation, activity, and survival signals merge in intracellular second messengers. These include cytoplasmic kinases of several families; differentiation pathways often terminate in Erk/Jun kinases or NF-kappaB. Key regulatory intermediates include TRAF6, src, Smad3, phosphatidylinositol-3-kinase, Jak/Stat, and the cGMP-dependent protein kinase I. There are substantial uncertainties regarding how intracellular agents connect to primary signals. The frontier includes characterization of how scaffolding/adapter proteins, such as cbl, gab, grb, p130Cas, and shc, as well as itam-containing proteins and nonreceptor tyrosine kinase adapters of the src and syk families, delimit and integrate signals of multiple receptors to bring about specific outcomes.
Collapse
Affiliation(s)
- Harry C Blair
- Department of Pathology, University of Pittsburgh, Veterans' Affairs Health System, Pittsburgh, PA 15261, USA.
| | | | | |
Collapse
|
29
|
Lane NE, Yao W, Nakamura MC, Humphrey MB, Kimmel D, Huang X, Sheppard D, Ross FP, Teitelbaum SL. Mice lacking the integrin beta5 subunit have accelerated osteoclast maturation and increased activity in the estrogen-deficient state. J Bone Miner Res 2005; 20:58-66. [PMID: 15619670 DOI: 10.1359/jbmr.041017] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Revised: 08/06/2004] [Accepted: 08/11/2004] [Indexed: 11/18/2022]
Abstract
UNLABELLED Integrin alphavbeta5 is expressed on osteoclast precursors and is capable of recognizing the same amino acid motif as alphavbeta3. Three-month-old beta5(-/-) female OVX mice had increased osteoclastogenesis ex vivo, and microCT assessment of trabecular bone volume was 53% lower than WT-OVX animals. These preliminary data suggest alphavbeta5 integrin's presence on osteoclast precursors may inhibit of osteoclast formation. INTRODUCTION Osteoclasts are unique resorptive skeletal cells, capable of degrading bone on contact to the juxtaposed matrix. Integrin alphavbeta5 is expressed on osteoclast precursors, structurally similar to alphavbeta3, and capable of recognizing the same amino acid motif. Given the structural relationship and reciprocal regulation of alphavbeta3 and alphavbeta5, the purpose of this study was to evaluate how alphavbeta5 might contribute to osteoclast maturation and activity. MATERIALS AND METHODS Three-month-old wildtype (WT) and beta5(-/-) female mice had ovariectomy (OVX) or sham operations. The osteoclastogenic capacity of marrow-derived precursors, the kinetic, the circulating, and structural parameters of bone remodeling, was determined after 6 weeks of paired feeding. RESULTS AND CONCLUSIONS OVX increased osteoclastogenesis ex vivo and in vivo. Osteoclast formation and prolonged pre-osteoclast survival were substantially enhanced in cultures containing beta5(-/-) cells whether obtained from sham-operated or OVX mice. Expression of cathepsin K, beta3 integrin subunit, and calcitonin receptor were accelerated in cultured beta5(-/-)osteoclasts. beta5(-/-) osteoclasts from OVX animals showed a 3-fold enhancement of net resorptive activity, with quantitative muCT showing trabecular bone volume loss after OVX 53% greater in beta5(-/-) OVX compared with similarly treated WT OVX mice (p < 0.05). alpha5beta3 seems to be an inhibitor of osteoclast formation, in contrast to alphavbeta3. In addition, loss of alphavbeta5 seems to accelerate osteoclast formation in the OVX model. Further examination of alphavbeta5 signaling pathways may enhance our understanding of the activation of bone resorption.
Collapse
Affiliation(s)
- Nancy E Lane
- Department of Medicine, University of California at San Francisco, San Francisco, California 94143, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Blair HC, Borysenko CW, Villa A, Schlesinger PH, Kalla SE, Yaroslavskiy BB, Garćia-Palacios V, Oakley JI, Orchard PJ. In vitro differentiation of CD14 cells from osteopetrotic subjects: contrasting phenotypes with TCIRG1, CLCN7, and attachment defects. J Bone Miner Res 2004; 19:1329-38. [PMID: 15231021 DOI: 10.1359/jbmr.040403] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2003] [Revised: 03/30/2004] [Accepted: 04/05/2004] [Indexed: 01/28/2023]
Abstract
UNLABELLED We studied osteoclastic differentiation from normal and osteopetrotic human CD14 cells in vitro. Defects in acid transport, organic matrix removal, and cell fusion with deficient attachment were found. Analysis of genotypes showed that TCIRG1 anomalies correlated with acid transport defects, but surprisingly, organic matrix removal failure correlated with CLCN7 defects; an attachment defect had normal TCIRG1 and CLCN7. INTRODUCTION Osteopetrotic subjects usually have normal macrophage activity, and despite identification of genetic defects associated with osteopetrosis, the specific developmental and biochemical defects in most cases are unclear. Indeed, patients with identical genotypes often have different clinical courses. We classified defects in osteoclast differentiation in vitro using four osteopetrotic subjects without immune or platelet defects, three of them severe infantile cases, compared with normals. MATERIALS AND METHODS Osteoclast differentiation used isolated CD14 cells; results were correlated with independent analysis of two key genes, CLCN7 and TCIRG1. CD14 cell attachment and cell surface markers and extent of differentiation in RANKL and colony-stimulating factor (CSF)-1 were studied using acid secretion, bone pitting, enzyme, and attachment proteins assays. RESULTS AND CONCLUSIONS CD14 cells from all subjects had similar lysosomal and nonspecific esterase activity. With the exception of cells from one osteopetrotic subject, CD14 cells from osteopetrotic and control monocytes attached similarly to bone or tissue culture substrate. Cells from one osteopetrotic subject, with normal CLCN7 and TCIRG1, did not attach to bone, did not multinucleate, and formed no podosomes or actin rings in RANKL and CSF-1. Attachment defects are described in osteopetrosis, most commonly mild osteopetrosis with Glantzman's thrombasthenia. However, this case, with abnormal integrin alphavbeta3 aggregates and no osteoclasts, seems to be unique. Two subjects were compound heterozygotes for TCIRG1 defects; both had CD14 cells that attached to bone but did not acidify attachments; cell fusion and attachment occurred, however, in RANKL and CSF-1. This is consistent with TCIRG1, essential for H+-ATPase assembly at the ruffled border. A compound heterozygote for CLCN7 defects had CD14 cells that fused in vitro, attached to bone, and secreted acid, TRACP, and cathepsin K. However, lacunae were shallow and retained demineralized matrix. This suggests that CLCN7 may not limit H+-ATPase activity as hypothesized, but may be involved in control of organic matrix degradation or removal.
Collapse
Affiliation(s)
- Harry C Blair
- Department of Pathology, University of Pittsburgh, Veteran's Affairs Medical Center, Pittsburgh, Pennsylvania 15261, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|