Mesenchyme
Editor's note: Katherine Koczwara created the above image for this article. You can find the full image and all relevant information here.
Mesenchyme is a type of animal tissue comprised of loose cells embedded in a mesh of proteins and fluid, called the extracellular matrix. The loose, fluid nature of mesenchyme allows its cells to migrate easily and play a crucial role in the origin and development of morphological structures during the embryonic and fetal stages of animal life. Mesenchyme directly gives rise to most of the bodys connective tissues, from bones and cartilage to the lymphatic and circulatory systems. Furthermore, the interactions between mesenchyme and another tissue type, epithelium, help to form nearly every organ in the body.
Although most mesenchyme derives from the middle embryological germ layer, the mesoderm, the outer germ layer known as the ectoderm also produces a small amount of mesenchyme from a specialized structure called the neural crest. Mesenchyme is generally a transitive tissue; while crucial to morphogenesis during development, little can be found in adult organisms. The exception is mesenchymal stem cells, which are found in small quantities in bone marrow, fat, muscles, and the dental pulp of baby teeth.
Mesenchyme forms early in embryonic life. As the primary germ layers develop during gastrulation, cell populations lose their adhesive properties and detach from sheets of connected cells, called epithelia. This process, known as an epithelial-mesenchymal transition, gives rise to the mesodermal layer of the embryo, and occurs many times throughout development of higher vertebrates. Epithelial-mesenchymal transitions play key roles in cellular proliferation and tissue repair, and are indicated in many pathological processes, including the development of excess fibrous connective tissue (fibrosis) and the spread of disease between organs (metastasis). The reverse process, the mesenchymal-epithelial transition, occurs when the loose cells of mesenchyme develop adhesive properties and arrange themselves into an organized sheet. This type of transition is also common during development, and is involved in kidney formation.
The concept of mesenchyme has a long history, which has shaped our modern understanding of the tissue in many ways. In 1879, Charles Sedgwick Minot, an anatomist based out of Harvard Medical School in Boston, Massachusetts, first described what he termed mesamoeboids, the cellular portion of what would soon come to be recognized as mesenchyme. Minot found these cells in the context of histological studies of mesoderm. He understood the loose, mobile cells of mesenchyme as primitive representatives of the mesoderm, but did not consider these cells as a type of tissue. Two years after Minots recognition of mesamoeboids, Oscar and Richard Hertwig, two brothers and doctoral students of Ernst Haeckel at the University of Jena in Jena, Germany, coined the term mesenchyma in their publication Die Coelomtheorie. Versucheiner Erklrung des mittleren Keimblattes (Coelom Theory: An attempt to explain the middle germ layer), and they used it to describe the type of tissue that was comprised of the amoeboid cells that Minot had portrayed. The Hertwig brothers established that mesenchyme originates from mesoderm, and they situated this relationship in the broader context of the development of the coelom, a fluid-filled body cavity. Their Die Coelomtheorie also advanced the idea that the three germ layers maintain separate identities and develop distinct tissues and organs, a concept known as germ-layer theory.
In 1888, N. Katschenko suggested that mesenchyme found in the region of the head originated from the neural crest, an ectodermal derivative, effectively expanding the tissues origins beyond that of a single germ layer. Five years later, Harvard Medical School doctoral student Julia Platt, in Cambridge, Massachusetts, provided evidence based on her studies of Necturus maculosus embryos, a type of aquatic salamander, that the mesenchyme that developed into the skeletal elements of the branchial arches derived from ectoderm. Platts 1893 publication, Ectodermic Origin of the Cartilages of the Head, and her conclusions about the ectodermal origins of mesenchyme in the head region, and thus skeletal and cartilaginous tissues of the skull, went against the entrenched germ-layer theory and the mesodermal origins of mesenchyme advocated by the Hertwig brothers in their 1881 Die Coelomtheorie. Platts findings were rejected by many established embryologists who upheld the theory of integrity of the germ layers.
In the years following Platts publication, several other embryologists identified ectodermal origins for mesenchyme and its derivative skeletal elements in the head region of fish and birds. It was not until nearly thirty years after Platts initial publication that independent studies demonstrated a major ectodermal contribution to mesenchyme. In 1921, while investigating the limits of neural crest in the formation of cerebral ganglia in Urodeles, commonly known as salamanders, Francis Landacre at the Ohio State University in Columbus, Ohio, showed the ectodermal origin of cranial mesenchyme. Landacres work was followed by other studies which further concluded an ectodermal component of mesenchyme. The idea that mesenchyme in the cranial region derived from neural crest was finally abrogated in the 1940s by the independent research of embryologists Sven Hrstadius at Uppsala University in Uppsala, Sweden, and Gavin de Beer at the University College in London, England.
Soon after the debate over ectodermal mesenchyme ended, research on the role of mesenchyme during development erupted. By the 1960s, embryologists realized that mesenchyme, in combination with epithelium, played an essential role in the morphogenesis of many organs during embryonic and fetal development. Epithelio-mesenchymal interactions form nearly every organ of the body, from hair and sweat glands to the digestive tract, kidneys, and teeth.
In 1969, Edward Kollar and Grace Baird from the University of Chicago in Chicago, Illinois, designed a series of experiments to understand how mesenchyme and epithelium work together when cells differentiate, and how the two tissues combine to make embryonic structures. Their research drew on a long history of investigating tissue interactions during morphogenesis, and especially on the 1954 work of John Cairn at the University of Texas in Austin, Texas, and John Saunders, at Marquette University in Milwaukee, Wisconsin. Cairn and Saunders recognized that mesoderm holds the inductive stimulus within interactions between mesoderm and epithelium. Using tooth development as a model system, Kollar and Baird provided evidence that mesenchyme drives both induction and differentiation during epithelio-mesenchymal interactions, and is thus the tissue that confers structural specificity during these interactions, or determines what structure will form. Kollar and Baird published their findings in 1969 in The Influence of the Dental Papilla on the Development of Tooth Shape in Embryonic Mouse Tooth Germs, and in 1970 in Tissue Interactions in Embryonic Mouse Tooth Germs.
Shortly before Kollar and Baird published their account of epithelio-mesenchymal interactions, Alexander Friedenstein discovered mesenchymal stem cells in mice (Mus musculus). In publications from 1966 through 1987, Friedenstein, in conjunction with his peers at the University of Moscow in Moscow, Russia, provided evidence from transplantation experiments that stem cells taken from bone marrow can differentiate into mesenchymal tissues, such as fat, bone, and cartilage. These cells came to be known as mesenchymal stem cells, and have subsequently been found in blood, cartilaginous, skeletal, and fatty tissues. Mesenchymal stem cells provide a reservoir of reserve cells that the body can use for normal or pathological tissue regeneration and repair. The abilities of mesenchymal stem cells to differentiate into different tissues, known as cell potency, has been a cause of debate in recent years, leading researchers to question whether these cells are truly multipotent, and can give rise to multiple cells types. The potential multipotency of mesenchymal stem cells, in conjunction with their presence in adult organisms, has made them an attractive alternative to embryonic stem cells for research on tissue regeneration.
Current research on mesenchyme spreads across many biological fields. The focus of mesenchyme research, however, divides between two general interests: the role and expression of mesenchyme-specific genes during development, including pathological processes, and the locations and capabilities of mesenchymal stem cells. While some still investigate mesenchyme at the tissue level, the two current focuses reflect a trend towards the analysis and understanding of molecular-level mechanisms by which mesenchyme functions during development. Beginning with the definition by the Hertwig brothers, mesenchyme research has moved from anatomical investigations in developing embryos, to cellular contributions for organ formation and tissue level interactions, and now to the genetic mechanisms of development and tissue repair.
There is historical continuity within mesenchyme research, but there remain vestiges of the controversy that surrounded this tissue in the late nineteenth century. In her 1893 article in which she introduced the biological community to the ectodermal origins of mesenchyme in the head region, Julia Platt also suggested a change in terminology. Mesenchyme of ectodermal origins she specified by the term mesectoderm, while mesodermal mesenchyme she called mesendoderm. The medical community, especially pathologists, still employs this distinction between mesenchymal sources, only referring to a tissue as mesenchyme if it is derived from mesoderm. Pathologists maintain the distinction because the mesenchymal source determines the type and behavior of a disease. Meanwhile, developmental biologists tend to recognize mesenchyme by a single name, regardless of source.
The study of mesenchyme has a long history, from mesenchyme's recognition within the framework of germ-layer theory, to controversy about mesenchyme's origins, to uncovering mesenchyme's roles in morphogenesis and its capacity to produce stem cells. This history is in part due to the fact that mesenchyme is crucial for embryonic growth and development, as well as maintenance of connective tissues in adulthood. The loose nature of cells within mesenchyme allows the tissue to move and to be molded. During embryogenesis, mesenchyme gives rise to the bodys connective tissues, from cartilage and bone to fat, muscle, and the circulatory system. Meanwhile, nearly every organ forms through epithelio-mesenchymal interactions, in which mesenchyme provides both the inductive stimulus and determines the path of differentiation. Although little mesenchyme remains in the body during adulthood, the final remnants of this tissue, mesenchymal stem cells, allow connective tissues to repair and regenerate.
MacCord, Kate, "Mesenchyme".
(2012-09-14). ISSN: 1940-5030 http://embryo.asu.edu/handle/10776/3941.
Arizona State University. School of Life Sciences. Center for Biology and Society. Embryo Project Encyclopedia.
Arizona Board of Regents Licensed as Creative Commons Attribution-NonCommercial-Share Alike 3.0 Unported (http://creativecommons.org/licenses/by-nc-sa/3.0/)
Mesoderm; Mesenchyme; Gastrulation; Minot, Charles Sedgwick, 1852-1914; Haeckel, Ernst, 1834-1919; Stem cells; Mesenchymal stem cells; Embryological development; Embryos; Cell differentiation; Concept
Read the rest here:
Mesenchyme | The Embryo Project Encyclopedia
- Mesenchymal Stem Cells Market to Witness an Outstanding Growth by 2030 - openPR - May 15th, 2024
- Eterna Therapeutics to Present at the ASGCT 27th Annual Meeting on Development of Beta 2 Microglobulin-Knockout ... - Yahoo Finance - May 11th, 2024
- Concise Review: Mesenchymal Stem Cells: From Roots to Boost - May 10th, 2024
- Storage conditions affect the composition of the lyophilized secretome of multipotent mesenchymal stromal cells ... - Nature.com - May 4th, 2024
- Mesenchymal Stem Cells Market Will Increase USD 10 Billion By 2033 - PharmiWeb.com - May 4th, 2024
- Mesenchymal stem cell based therapies for uveitis: a systematic review of preclinical studies | Eye - Nature.com - April 10th, 2024
- Development of exosome therapy to treat inflammatory bowel disease by VesiCURE Therapeutics - StreetInsider.com - April 10th, 2024
- Adipose Derived Stem Cell Therapy Market Will Show the Highest Growth Rates, Incredible Demand by 2031 - WhaTech - April 3rd, 2024
- Injectable microspheres adhering to the cartilage matrix promote rapid reconstruction of partial-thickness cartilage defects - ScienceDirect.com - March 30th, 2024
- Safety and Potential Effect of Intrauterine Infusion of Autologous Adipose Tissue-Derived Regenerative Cells in ... - Cureus - March 30th, 2024
- Instructing iPS cell-derived mesenchymal stem cells to inhibit abnormal bone formation in FOP - Medical Xpress - March 28th, 2024
- Clinical application of mesenchymal stem cell in regenerative medicine ... - March 22nd, 2024
- Mesenchymal Stem Cells: The Past Present and Future - March 22nd, 2024
- CytoMed Diversifies into Regenerative Medicine after Research Collaboration with Singapore's Sengkang General ... - Yahoo Finance - March 20th, 2024
- Overexpression of Wnt5a promoted the protective effect of mesenchymal stem cells on Lipopolysaccharide-induced ... - BMC Infectious Diseases - March 20th, 2024
- Mesenchymal Stem Cells: What We Have Learned and How to Manage Them - MDPI - March 17th, 2024
- Mesenchymal stem cells and their microenvironment - March 17th, 2024
- Mesenchymal stem/stromal cells as a valuable source for the treatment ... - March 17th, 2024
- Proteomic characterization of hUC-MSC extracellular vesicles and evaluation of its therapeutic potential to treat ... - Nature.com - March 13th, 2024
- The impact understanding of exosome therapy in COVID-19 and preparations for the future approaches in dealing with ... - Nature.com - March 13th, 2024
- CytoMed Therapeutics Limited Announces Research Collaboration with Singapore Sengkang General Hospital to ... - Yahoo Finance UK - March 7th, 2024
- CytoMed Therapeutics Limited Announces Research Collaboration with Singapore Sengkang General Hospital to ... - Yahoo Finance - March 6th, 2024
- Combatting osteoarthritis with cartilage replacement therapy - Drug Target Review - March 3rd, 2024
- Ethical considerations in Stem Cell therapy for ALS - Cyprus Mail - February 27th, 2024
- Therapeutic Solutions International Files Patent on Facilitating Effects of JadiCells on Gene Therapy Mediated Cell ... - Business Wire - February 27th, 2024
- Stem Cell Therapy for Ulcerative Colitis - Health Central - February 27th, 2024
- Expanding the Horizons of Cell and Gene Therapy - RegMedNet - February 24th, 2024
- Early differentiation of mesenchymal stem cells is reflected in their dielectrophoretic behavior | Scientific Reports - Nature.com - February 22nd, 2024
- Orthopaedics Department's Regenerative Research Highlighted at ORS Annual Meeting - InventUM - University of Miami - February 20th, 2024
- Cellular uptake and in vivo distribution of mesenchymal-stem-cell-derived extracellular vesicles are protein corona ... - Nature.com - February 18th, 2024
- New University spin-out developing novel adult stem cell-based Therapies - News - University of Liverpool - News - February 15th, 2024
- Examining the potential of the common bovine as a potential therapeutic research model - Medical Xpress - February 15th, 2024
- Intentional Interference: Genetic Engineering Medium Aids The Transfection Of MSCs With siRNA - BioProcess Online - February 15th, 2024
- Cellular senescence is associated with osteonecrosis of the femoral head while mesenchymal stem cell conditioned ... - Nature.com - February 9th, 2024
- Stem Cell Therapy for Crohns Disease Shows Promising Results - RegMedNet - February 9th, 2024
- Targeted transcriptomic analysis of synovial tissues from horses with septic arthritis treated with immune-activated ... - American Veterinary Medical... - February 7th, 2024
- Mesenchymal Stem Cell Immunomodulation: Mechanisms and ... - Cell Press - February 7th, 2024
- New Cell Therapy for ARDS: A Groundbreaking Development and Other Respiratory Health Breakthroughs - Medriva - February 7th, 2024
- Effective treatment of optic neuropathies by intraocular delivery of MSC-sEVs through augmenting the G-CSF ... - pnas.org - January 31st, 2024
- Global Stem Cell Therapy Industry Outlook to 2028, Driven by Therapeutic Innovations and Clinical Advancements ... - Yahoo Finance - January 29th, 2024
- Out-of-this-world study will test how stem cells function in space - YP - January 29th, 2024
- The Applications of Cell Therapy - Technology Networks - January 26th, 2024
- STEM CELL THERAPY FOR MS COST: WHAT YOU NEED TO KNOW? - Island Echo - January 24th, 2024
- Understanding Neuromyelitis Optica: Role of NF-B and Therapeutic Potential - Medriva - January 20th, 2024
- Faculty member Arnold Caplan passes away The Daily The Daily - The Daily | Case Western Reserve University - January 18th, 2024
- Effects of fine particulate matter on bone marrow-conserved hematopoietic and mesenchymal stem cells: a systematic ... - Nature.com - January 11th, 2024
- Expression of HLA-DR by mesenchymal stromal cells in the platelet lysate era: an obsolete release criterion for MSCs ... - Journal of Translational... - January 11th, 2024
- NurOwn and its exosomes for ALS given patents in Europe, elsewhere - ALS News Today - January 8th, 2024
- Single-cell analysis reveals the stromal dynamics and tumor-specific characteristics in the microenvironment of ovarian ... - Nature.com - January 8th, 2024
- First in Class Combination Stem Cell and Exosome Therapy to Treat Pulmonary Fibrosis in Long Haul Covid Patients ... - Yahoo Finance - January 4th, 2024
- Choosing the Right Excipients for MSC and iPSC Therapies - Pharmaceutical Technology Magazine - January 4th, 2024
- Mitochondria Transplantation Therapy It's Farther Along Than You Think - BioProcess Online - January 2nd, 2024
- Embryonic-stem-cell-derived mesenchymal stem cells relieve experimental contact urticaria by regulating the functions ... - Nature.com - December 21st, 2023
- Type I collagen and fibromodulin enhance the tenogenic phenotype of hASCs and their potential for tendon ... - Nature.com - December 19th, 2023
- Could the 'central dogma' of biology be misleading bioengineers? - Phys.org - December 13th, 2023
- The Risks of Stem Cell and Exosome Treatments for Long COVID: A Call for Stricter Regulations - Medriva - December 13th, 2023
- Mesenchymal stem cells from biology to therapy - PMC - December 11th, 2023
- The Safety and Efficacy of Human Umbilical Cord-Derived ... - Cureus - December 5th, 2023
- The pivotal role of Nrf2 signal axis in IDD | JIR - Dove Medical Press - December 5th, 2023
- Futuristic Novel Therapeutic Approaches in the Treatment of ... - Cureus - December 3rd, 2023
- Cartilage's Contribution in Otology: A Comprehensive Review of Its ... - Cureus - December 3rd, 2023
- Mesenchymal stem or stromal cells: a review of clinical applications ... - November 29th, 2023
- Comparative evaluation of 3D-printed and conventional implants in ... - Nature.com - November 29th, 2023
- Expression of E-cadherin and N-cadherin in Epithelial-to ... - Cureus - November 29th, 2023
- Enhancing the immunosuppressive properties of human umbilical cord mesenchymal stem cells - Phys.org - November 29th, 2023
- 'Great Potential' in Stem Cell Therapies for Knee Osteoarthritis ... - Pain News Network - November 25th, 2023
- Dietary Sources, Bioavailability, and Functions of Ascorbic Acid ... - Cureus - November 25th, 2023
- FY 2024 VA-Funded Projects - VA's Office of Research and Development - November 25th, 2023
- Real-world data suggest effectiveness of the allogeneic ... - Journal of Translational Medicine - November 23rd, 2023
- Mesenchymal Stem Cells: Characteristics, Function, and Application - November 23rd, 2023
- Combined application of therapeutic viruses and nanomaterials to ... - News-Medical.Net - November 23rd, 2023
- Progress in the Development of Stem Cell-Derived Cell-Free ... - Dove Medical Press - November 23rd, 2023
- Improving the therapeutic efficacy of oncolytic viruses for cancer ... - Journal of Translational Medicine - November 23rd, 2023
- 11.22.23 -- How To Lose A Batch In 10 Days - BioProcess Online - November 23rd, 2023
- The Pros and Cons of Mesenchymal Stem Cell-Based Therapies - November 19th, 2023
- Leptin's influence on MMP-1 expression | JIR - Dove Medical Press - November 15th, 2023
- TWIST1 and TSG6 are coordinately regulated and function as ... - Science - November 11th, 2023
- Association between severe acute malnutrition in childhood and ... - BioMed Central - November 11th, 2023
- Global Market for Treatments for Syndromes of Progressive Ataxia and Weakness Disorders - Yahoo Finance - November 11th, 2023
- Stem Cell Restore Reviews - Does It Work? Real Green Valley ... - The Daily World - November 11th, 2023
Recent Comments