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Nature Reviews. Molecular Cell Biology Dec 2014The biochemical and biophysical properties of the extracellular matrix (ECM) dictate tissue-specific cell behaviour. The molecules that are associated with the ECM of... (Review)
Review
The biochemical and biophysical properties of the extracellular matrix (ECM) dictate tissue-specific cell behaviour. The molecules that are associated with the ECM of each tissue, including collagens, proteoglycans, laminins and fibronectin, and the manner in which they are assembled determine the structure and the organization of the resultant ECM. The product is a specific ECM signature that is comprised of unique compositional and topographical features that both reflect and facilitate the functional requirements of the tissue.
Topics: Animals; Basement Membrane; Extracellular Matrix; Extracellular Matrix Proteins; Humans; Neurons; Proteoglycans
PubMed: 25370693
DOI: 10.1038/nrm3902 -
German Medical Science : GMS E-journal 2022Since the era when macular hole was considered untreatable, macular hole surgery has come a long way to being one of the most successful surgeries. Internal limiting... (Review)
Review
Since the era when macular hole was considered untreatable, macular hole surgery has come a long way to being one of the most successful surgeries. Internal limiting membrane (ILM) peeling has been an essential step of macular hole surgery since the establishment of the role of ILM in the aetiopathogenesis and progression of macular hole. However, the novel technique was not all virtuous. It had some vices which were not evident immediately. With the advent of spectral domain optical coherence tomography, short- and long-term effects of ILM peeling on macular structures were known; and with microperimetry, its effect on the function of macula could be evaluated. The technique has evolved with time from total peeling to inverted flap to just temporal peeling and temporal flap in an attempt to mitigate its adverse effects and to improve its surgical outcome. ILM abrasion technique and Ocriplasmin may eliminate the need of ILM peeling in selected cases, but they have their own limitations. We here discuss the role of ILM in the pathogenesis of macular hole, the benefits and adverse effects of ILM peeling, and the various modifications of the procedure, to then explore the alternatives.
Topics: Basement Membrane; Epiretinal Membrane; Humans; Retinal Perforations; Retrospective Studies; Treatment Outcome; Visual Acuity; Vitrectomy
PubMed: 35813123
DOI: 10.3205/000309 -
Journal of Anatomy Apr 2019Recreating the structure of human tissues in the laboratory is valuable for fundamental research, testing interventions, and reducing the use of animals. Critical to the...
Recreating the structure of human tissues in the laboratory is valuable for fundamental research, testing interventions, and reducing the use of animals. Critical to the use of such technology is the ability to produce tissue models that accurately reproduce the microanatomy of the native tissue. Current artificial cell-based skin systems lack thorough characterisation, are not representative of human skin, and can show variation. In this study, we have developed a novel full thickness model of human skin comprised of epidermal and dermal compartments. Using an inert porous scaffold, we created a dermal construct using human fibroblasts that secrete their own extracellular matrix proteins, which avoids the use of animal-derived materials. The dermal construct acts as a foundation upon which epidermal keratinocytes were seeded and differentiated into a stratified keratinised epithelium. In-depth morphological analyses of the model demonstrated very close similarities with native human skin. Extensive immunostaining and electron microscopy analysis revealed ultrastructural details such as keratohyalin granules and lamellar bodies within the stratum granulosum, specialised junctional complexes, and the presence of a basal lamina. These features reflect the functional characteristics and barrier properties of the skin equivalent. Robustness and reproducibility of in vitro models are important attributes in experimental practice, and we demonstrate the consistency of the skin construct between different users. In summary, a new model of full thickness human skin has been developed that possesses microanatomical features reminiscent of native tissue. This skin model platform will be of significant interest to scientists researching the structure and function of human skin.
Topics: Basement Membrane; Cell Differentiation; Cells, Cultured; Dermis; Epidermis; Extracellular Matrix Proteins; Fibroblasts; Humans; In Vitro Techniques; Keratinocytes; Microscopy, Electron; Skin; Tissue Engineering
PubMed: 30740672
DOI: 10.1111/joa.12942 -
Molecular Neurodegeneration Dec 2021Neurodegenerative disorders are a group of age-associated diseases characterized by progressive degeneration of the structure and function of the CNS. Two key... (Review)
Review
BACKGROUND
Neurodegenerative disorders are a group of age-associated diseases characterized by progressive degeneration of the structure and function of the CNS. Two key pathological features of these disorders are blood-brain barrier (BBB) breakdown and protein aggregation.
MAIN BODY
The BBB is composed of various cell types and a non-cellular component---the basal lamina (BL). Although how different cells affect the BBB is well studied, the roles of the BL in BBB maintenance and function remain largely unknown. In addition, located in the perivascular space, the BL is also speculated to regulate protein clearance via the meningeal lymphatic/glymphatic system. Recent studies from our laboratory and others have shown that the BL actively regulates BBB integrity and meningeal lymphatic/glymphatic function in both physiological and pathological conditions, suggesting that it may play an important role in the pathogenesis and/or progression of neurodegenerative disorders. In this review, we focus on changes of the BL and its major components during aging and in neurodegenerative disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS). First, we introduce the vascular and lymphatic systems in the CNS. Next, we discuss the BL and its major components under homeostatic conditions, and summarize their changes during aging and in AD, PD, and ALS in both rodents and humans. The functional significance of these alterations and potential therapeutic targets are also reviewed. Finally, key challenges in the field and future directions are discussed.
CONCLUSIONS
Understanding BL changes and the functional significance of these changes in neurodegenerative disorders will fill the gap of knowledge in the field. Our goal is to provide a clear and concise review of the complex relationship between the BL and neurodegenerative disorders to stimulate new hypotheses and further research in this field.
Topics: Alzheimer Disease; Basement Membrane; Blood-Brain Barrier; Glymphatic System; Humans; Neurodegenerative Diseases
PubMed: 34876200
DOI: 10.1186/s13024-021-00502-y -
Current Opinion in Nephrology and... May 2016Glomerular filtration occurs in specialized, microscopic organelles. Each glomerulus contains unique cells and these cooperate to maintain normal filtration. Phenomenal... (Review)
Review
PURPOSE OF REVIEW
Glomerular filtration occurs in specialized, microscopic organelles. Each glomerulus contains unique cells and these cooperate to maintain normal filtration. Phenomenal adaptation is required for the glomerulus to respond to variable mechanical loads and this adaptation requires efficient communication between the resident cells. This review will focus on the latest discoveries related to signalling events that mediate the crosstalk between glomerular cells, and detail how disease processes can influence normal regulation.
RECENT FINDINGS
New data indicate that the crosstalk between glomerular cells involves an increasing number of secreted signalling ligands that act in an autocrine or paracrine fashion. Furthermore, extended roles for some of the classical signalling molecules have been described and there is emerging evidence of therapeutic strategies to manipulate cellular crosstalk. The glomerular extracellular matrix harbours many of these signalling ligands, acting as a reservoir and presenting ligands to cell surface receptors. Signals can also be transferred between cells by extracellular vesicles and this is an emerging concept in cellular crosstalk.
SUMMARY
Recent discoveries are building our understanding about glomerular cell crosstalk, and this review focuses on growth factors and signalling peptides, methods of delivery to target cells, and the potential for developing new therapies for glomerular disease.
Topics: Animals; Basement Membrane; Cell Communication; Extracellular Matrix; Humans; Kidney Diseases; Kidney Glomerulus; Signal Transduction
PubMed: 27027682
DOI: 10.1097/MNH.0000000000000221 -
The Journal of Investigative Dermatology Jun 1990Fibronectins are widespread extracellular matrix and body fluid glycoproteins, capable of multiple interactions with cell surfaces and other matrix components. Their... (Review)
Review
Fibronectins are widespread extracellular matrix and body fluid glycoproteins, capable of multiple interactions with cell surfaces and other matrix components. Their structure at a molecular level has been resolved, yet there are still many unanswered questions regarding their biologic activity in vivo. Much data suggests that fibronectins may promote extracellular matrix assembly, and cell adhesion to those matrices. However, one outstanding enigma is that fibronectins may, under different circumstances, promote both cell migration and anchorage. An analysis of the interaction of fibroblasts with proteolytically derived and purified domains of plasma fibronectin revealed that the type of adhesion and the correlated cytoskeletal organization depended on multiple interactions of fibronectin domains with the cell surface. Human dermal fibroblasts were capable of interacting with the integrin-binding domain and both heparin-binding domains of the plasma fibronectin molecule and their interactions determined the type of adhesion. The same principle was seen in a study of the ability of plasma fibronectin to promote basement membrane assembly in an endodermal cell line, PF-HR9. There also, interactions of both heparin- and integrin-binding domains combined to promote the deposition of a proteoglycan, laminin, and type IV collagen-containing basement membrane matrix. The underlying conclusion from our studies is, therefore, that fibronectins may, through their different isotypes, multiple receptors, and varying interaction of one or more domains with those receptors, result in a spectrum of responses in different cell types. The molecular details of this array of biologic activities is not resolved but is the target of much current research.
Topics: Animals; Basement Membrane; Cell Adhesion; Cytoskeleton; Fibronectins; Humans; Skin
PubMed: 2191056
DOI: 10.1111/1523-1747.ep12874973 -
Stroke and Vascular Neurology Jul 2019The blood-brain barrier (BBB) is a highly complex and dynamic structure, mainly composed of brain microvascular endothelial cells, pericytes, astrocytes and the basement... (Review)
Review
The blood-brain barrier (BBB) is a highly complex and dynamic structure, mainly composed of brain microvascular endothelial cells, pericytes, astrocytes and the basement membrane (BM). The vast majority of BBB research focuses on its cellular constituents. Its non-cellular component, the BM, on the other hand, is largely understudied due to its intrinsic complexity and the lack of research tools. In this review, we focus on the role of the BM in BBB integrity. We first briefly introduce the biochemical composition and structure of the BM. Next, the biological functions of major components of the BM in BBB formation and maintenance are discussed. Our goal is to provide a concise overview on how the BM contributes to BBB integrity.
Topics: Animals; Basement Membrane; Blood-Brain Barrier; Capillary Permeability; Collagen Type IV; Extracellular Matrix Proteins; Heparan Sulfate Proteoglycans; Humans; Laminin; Membrane Glycoproteins; Signal Transduction
PubMed: 31338215
DOI: 10.1136/svn-2018-000198 -
The Journal of Investigative Dermatology Jul 1975Ultrastructurally, the epidermal-dermal junction is composed of four component areas:(1) the basal cell plasma membrane with its specialized attachment devices or...
Ultrastructurally, the epidermal-dermal junction is composed of four component areas:(1) the basal cell plasma membrane with its specialized attachment devices or hemidesmosomes, (2) an electron-lucent area, the lamina lucida, (3) the basal lamina, and (4) the sub-basal lamina fibrous components, including anchoring fibrils, dermal microfibril bundles, and collagen fibers. The light microscopic "basement membrane" comprises only the sub-basal lamina fibrous zone. Other cell types, including melanocytes and Merkel cells, are also found at the epidermal-dermal junction. Structures at the junction derive their origin from the epidermis and dermis: the basal lamina is primarily of epidermal origin, the anchoring fibrils of dermal origin. The junction serves the following functions: (1) epidermal-dermal adherence, (2) mechanical support for the epidermis, and (3) a barrier to the exchange of cells and of some large molecules across the junction.
Topics: Animals; Basement Membrane; Cell Adhesion; Cell Aggregation; Cell Differentiation; Cell Membrane; Cell Movement; Chick Embryo; Collagen; Desmosomes; Fluorescent Antibody Technique; Humans; Immunoglobulins; Lupus Erythematosus, Systemic; Melanocytes; Membrane Potentials; Pemphigus; Receptors, Antigen, B-Cell; Skin; Skin Physiological Phenomena
PubMed: 1097542
DOI: 10.1111/1523-1747.ep12598050 -
The American Journal of Pathology Nov 1974The basal lamina is an extracellular scaffold positioned between parenchymal cells and connective tissue. Parenchymal cells attach to one of its surfaces and the other... (Review)
Review
The basal lamina is an extracellular scaffold positioned between parenchymal cells and connective tissue. Parenchymal cells attach to one of its surfaces and the other is anchored to connective tissue. By its presence it defines the spatial relationships among similar and dissimilar types of cells and between these cells and the space occupied by connective and supportive tissues. Replenishment of cells which have died during normal functioning or have become damaged in course of injury occurs with new cells in an orderly way along the framework of the basal lamina scaffold. This process appears to be aided by the polarity of the basal lamina and by an apparent specificity for cell types, and it enables multicellular organisms to reconstitute histologic structures of most tissues and organs to what they were prior to loss of cells. If the basal lamina is destroyed, the healing in most tissues results in formation of scar and loss of function. The properties of the basal lamina concerned with maintenance of histologic order in organs and tissues offer new ways to interpret the pathogenesis of several common disorders, including emphysema, scars, adhesions, cirrhosis of liver and excessive accumulation of basal lamina material as, for example, it occurs in patients with diabetes mellitus.
Topics: Animals; Basement Membrane; Cicatrix; Endothelium; Epithelial Cells; Epithelium; Humans; Islets of Langerhans; Kidney; Kidney Diseases; Liver; Liver Diseases; Lung; Lung Diseases; Muscles; Muscular Diseases; Nerve Tissue; Nervous System; Nervous System Diseases; Pancreas; Pancreatic Diseases; Skin; Skin Diseases; Wound Healing; Wounds and Injuries
PubMed: 4614671
DOI: No ID Found -
Journal of Cerebral Blood Flow and... Nov 2022Laminin, a major component of the basal lamina (BL), is a heterotrimeric protein with many isoforms. In the CNS, laminin is expressed by almost all cell types, yet... (Review)
Review
Laminin, a major component of the basal lamina (BL), is a heterotrimeric protein with many isoforms. In the CNS, laminin is expressed by almost all cell types, yet different cells synthesize distinct laminin isoforms. By binding to its receptors, laminin exerts a wide variety of important functions. However, due to the reciprocal and cell-specific expression of laminin in different cells at the neurovascular unit, its functions in blood-brain barrier (BBB) maintenance and BBB repair after injury are not fully understood. In this review, we focus on the expression and functions of laminin and its receptors in the neurovascular unit under both physiological and pathological conditions. We first briefly introduce the structures of laminin and its receptors. Next, the expression and functions of laminin and its receptors in the CNS are summarized in a cell-specific manner. Finally, we identify the knowledge gap in the field and discuss key questions that need to be answered in the future. Our goal is to provide a comprehensive overview on cell-specific expression of laminin and its receptors in the CNS and their functions on BBB integrity.
Topics: Basement Membrane; Biological Transport; Blood-Brain Barrier; Laminin; Receptors, Laminin
PubMed: 35796497
DOI: 10.1177/0271678X221113027