1
|
Rux D, Helbig K, Koyama E, Pacifici M. Hox11 expression characterizes developing zeugopod synovial joints and is coupled to postnatal articular cartilage morphogenesis into functional zones in mice. Dev Biol 2021; 477:49-63. [PMID: 34010606 DOI: 10.1016/j.ydbio.2021.05.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Revised: 04/07/2021] [Accepted: 05/10/2021] [Indexed: 11/26/2022]
Abstract
Previous studies on mouse embryo limbs have established that interzone mesenchymal progenitor cells emerging at each prescribed joint site give rise to joint tissues over fetal time. These incipient tissues undergo structural maturation and morphogenesis postnatally, but underlying mechanisms of regulation remain unknown. Hox11 genes dictate overall zeugopod musculoskeletal patterning and skeletal element identities during development. Here we asked where these master regulators are expressed in developing limb joints and whether they are maintained during postnatal zeugopod joint morphogenesis. We found that Hoxa11 was predominantly expressed and restricted to incipient wrist and ankle joints in E13.5 mouse embryos, and became apparent in medial and central regions of knees by E14.5, though remaining continuously dormant in elbow joints. Closer examination revealed that Hoxa11 initially characterized interzone and neighboring cells and was then restricted to nascent articular cartilage, intra joint ligaments and structures such as meniscal horns over prenatal time. Postnatally, articular cartilage progresses from a nondescript cell-rich, matrix-poor tissue to a highly structured, thick, zonal and mechanically competent tissue with chondrocyte columns over time, most evident at sites such as the tibial plateau. Indeed, Hox11 expression (primarily Hoxa11) was intimately coupled to such morphogenetic processes and, in particular, to the topographical rearrangement of chondrocytes into columns within the intermediate and deep zones of tibial plateau that normally endures maximal mechanical loads. Revealingly, these expression patterns were maintained even at 6 months of age. In sum, our data indicate that Hox11 genes remain engaged well beyond embryonic synovial joint patterning and are specifically tied to postnatal articular cartilage morphogenesis into a zonal and resilient tissue. The data demonstrate that Hox11 genes characterize adult, terminally differentiated, articular chondrocytes and maintain region-specificity established in the embryo.
Collapse
Affiliation(s)
- Danielle Rux
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA.
| | - Kimberly Helbig
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Eiki Koyama
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Maurizio Pacifici
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| |
Collapse
|
2
|
Decker RS, Um HB, Dyment NA, Cottingham N, Usami Y, Enomoto-Iwamoto M, Kronenberg MS, Maye P, Rowe DW, Koyama E, Pacifici M. Cell origin, volume and arrangement are drivers of articular cartilage formation, morphogenesis and response to injury in mouse limbs. Dev Biol 2017; 426:56-68. [PMID: 28438606 DOI: 10.1016/j.ydbio.2017.04.006] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 04/13/2017] [Accepted: 04/17/2017] [Indexed: 11/16/2022]
Abstract
Limb synovial joints are composed of distinct tissues, but it is unclear which progenitors produce those tissues and how articular cartilage acquires its functional postnatal organization characterized by chondrocyte columns, zone-specific cell volumes and anisotropic matrix. Using novel Gdf5CreERT2 (Gdf5-CE), Prg4-CE and Dkk3-CE mice mated to R26-Confetti or single-color reporters, we found that knee joint progenitors produced small non-migratory progenies and distinct local tissues over prenatal and postnatal time. Stereological imaging and quantification indicated that the columns present in juvenile-adult tibial articular cartilage consisted of non-daughter, partially overlapping lineage cells, likely reflecting cell rearrangement and stacking. Zone-specific increases in cell volume were major drivers of tissue thickening, while cell proliferation or death played minor roles. Second harmonic generation with 2-photon microscopy showed that the collagen matrix went from being isotropic and scattered at young stages to being anisotropic and aligned along the cell stacks in adults. Progenitor tracing at prenatal or juvenile stages showed that joint injury provoked a massive and rapid increase in synovial Prg4+ and CD44+/P75+ cells some of which filling the injury site, while neighboring chondrocytes appeared unresponsive. Our data indicate that local cell populations produce distinct joint tissues and that articular cartilage growth and zonal organization are mainly brought about by cell volume expansion and topographical cell rearrangement. Synovial Prg4+ lineage progenitors are exquisitely responsive to acute injury and may represent pioneers in joint tissue repair.
Collapse
Affiliation(s)
- Rebekah S Decker
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States.
| | - Hyo-Bin Um
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Nathaniel A Dyment
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT 06030, United States
| | - Naiga Cottingham
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Yu Usami
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Motomi Enomoto-Iwamoto
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Mark S Kronenberg
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT 06030, United States
| | - Peter Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT 06030, United States
| | - David W Rowe
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT 06030, United States
| | - Eiki Koyama
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Maurizio Pacifici
- Division of Orthopaedic Surgery, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States.
| |
Collapse
|
3
|
Decker RS, Koyama E, Enomoto-Iwamoto M, Maye P, Rowe D, Zhu S, Schultz PG, Pacifici M. Mouse limb skeletal growth and synovial joint development are coordinately enhanced by Kartogenin. Dev Biol 2014; 395:255-67. [PMID: 25238962 PMCID: PMC4253021 DOI: 10.1016/j.ydbio.2014.09.011] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 07/31/2014] [Accepted: 09/09/2014] [Indexed: 11/28/2022]
Abstract
Limb development requires the coordinated growth of several tissues and structures including long bones, joints and tendons, but the underlying mechanisms are not wholly clear. Recently, we identified a small drug-like molecule - we named Kartogenin (KGN) - that greatly stimulates chondrogenesis in marrow-derived mesenchymal stem cells (MSCs) and enhances cartilage repair in mouse osteoarthritis (OA) models. To determine whether limb developmental processes are regulated by KGN, we tested its activity on committed preskeletal mesenchymal cells from mouse embryo limb buds and whole limb explants. KGN did stimulate cartilage nodule formation and more strikingly, boosted digit cartilaginous anlaga elongation, synovial joint formation and interzone compaction, tendon maturation as monitored by ScxGFP, and interdigit invagination. To identify mechanisms, we carried out gene expression analyses and found that several genes, including those encoding key signaling proteins, were up-regulated by KGN. Amongst highly up-regulated genes were those encoding hedgehog and TGFβ superfamily members, particularly TFGβ1. The former response was verified by increases in Gli1-LacZ activity and Gli1 mRNA expression. Exogenous TGFβ1 stimulated cartilage nodule formation to levels similar to KGN, and KGN and TGFβ1 both greatly enhanced expression of lubricin/Prg4 in articular superficial zone cells. KGN also strongly increased the cellular levels of phospho-Smads that mediate canonical TGFβ and BMP signaling. Thus, limb development is potently and harmoniously stimulated by KGN. The growth effects of KGN appear to result from its ability to boost several key signaling pathways and in particular TGFβ signaling, working in addition to and/or in concert with the filamin A/CBFβ/RUNX1 pathway we identified previously to orchestrate overall limb development. KGN may thus represent a very powerful tool not only for OA therapy, but also limb regeneration and tissue repair strategies.
Collapse
Affiliation(s)
- Rebekah S Decker
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children׳s Hospital of Philadelphia, 3615 Civic Center Blvd, Philadelphia, PA 19104, USA.
| | - Eiki Koyama
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children׳s Hospital of Philadelphia, 3615 Civic Center Blvd, Philadelphia, PA 19104, USA
| | - Motomi Enomoto-Iwamoto
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children׳s Hospital of Philadelphia, 3615 Civic Center Blvd, Philadelphia, PA 19104, USA
| | - Peter Maye
- Department of Reconstructive Sciences, University of Connecticut Health Center School of, Dental Medicine, 263 Farmington Ave, Farmington, CT 06030, USA
| | - David Rowe
- Department of Reconstructive Sciences, University of Connecticut Health Center School of, Dental Medicine, 263 Farmington Ave, Farmington, CT 06030, USA
| | - Shoutian Zhu
- California Institute for Biomedical Research, 11119 North Torrey Pines Road, Suite 100, La Jolla, CA 92037, USA
| | - Peter G Schultz
- The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Maurizio Pacifici
- Translational Research Program in Pediatric Orthopaedics, Division of Orthopaedic Surgery, The Children׳s Hospital of Philadelphia, 3615 Civic Center Blvd, Philadelphia, PA 19104, USA
| |
Collapse
|
4
|
Abstract
Limb synovial joints are intricate structures composed of articular cartilage, synovial membranes, ligaments and an articular capsule. Together, these tissues give each joint its unique shape, organization and biomechanical function. Articular cartilage itself is rather complex and organized in distinct zones, including the superficial zone that produces lubricants and contains stem/progenitor cells. For many years there has been great interest in deciphering the mechanisms by which the joints form and come to acquire such unique structural features and diversity. Decades ago, classic embryologists discovered that the first overt sign of joint formation at each prescribed limb site was the appearance of a dense and compact population of mesenchymal cells collectively called the interzone. Work carried out since then by several groups has provided evidence that the interzone cells actively participate in joint tissue formation over developmental time. This minireview provides a succinct but comprehensive description of the many important recent advances in this field of research. These include studies using various conditional reporter mice to genetically trace and track the origin, fate and possible function of joint progenitor cells; studies on the involvement and roles in signaling pathways and transcription factors in joint cell determination and functioning; and studies using advanced methods of gene expression analyses to uncover novel genetic determinants of joint formation and diversity. The overall advances are impressive, and the findings are not only of obvious interest and importance but also have major implications in the conception of future translational medicine tools to repair and regenerate defective, overused or aging joints.
Collapse
|