Related Experiment Video
Updated: May 20, 2026
09:40
A Rapid, Scalable Method for the Isolation, Functional Study, and Analysis of Cell-derived Extracellular Matrix
Published on: January 4, 2017
Concepts in psoriasis: psoriasis and the extracellular matrix
J McFadden1, L Fry, A V Powles
1Department of Cutaneous Allergy, St John's Institute of Dermatology, St Thomas' Hospital, London SE1 7EH, U.K. john.mcfadden@kcl.ac.uk
The British Journal of Dermatology
|July 19, 2012
Summary
Guttate psoriasis may progress to plaque psoriasis if streptococcal enzymes damage the skin's basement membrane. Prompt antibody response can neutralize these enzymes, allowing spontaneous resolution of guttate psoriasis.
Area of Science:
- Dermatology
- Immunology
- Molecular Biology
Background:
- Psoriasis progression from guttate to plaque forms is not fully understood.
- Extradomain A+ fibronectin (EDA+ FN) feedback loops are implicated in psoriasis pathogenesis.
- The keratinocyte loop, involving α5β1 integrin, is crucial in psoriasis.
Purpose of the Study:
- To investigate the role of streptococcal lytic enzymes in initiating basement membrane disruption in guttate psoriasis.
- To explore the mechanism by which guttate psoriasis progresses to plaque psoriasis.
- To elucidate the influence of humoral immune responses on psoriasis progression and resolution.
Main Methods:
- Analysis of basement membrane integrity in psoriasis patients.
- Assessment of EDA+ FN and α5β1 integrin expression in keratinocytes.
- Postulation of streptokinase's role in laminin layer disruption via plasminogen activation.
- Consideration of keratinocyte-derived plasminogen-activating factors in laminin digestion.
Main Results:
- Basement membrane laminin disruption and increased α5β1 integrin expression are observed in uninvolved psoriatic skin.
- Streptococcal lytic enzymes, particularly streptokinase, are hypothesized to initiate laminin layer disruption.
- Keratinocyte proliferation and plasminogen activation contribute to basement membrane damage.
Conclusions:
- Spontaneous resolution of guttate psoriasis depends on timely neutralization of streptococcal enzymes before irreversible basement membrane damage.
- Failure to neutralize enzymes leads to chronic keratinocyte destabilization and plaque psoriasis development.
- Humoral immune responses play a key role in determining the progression or resolution of guttate psoriasis.
Related Concept Videos
01:29The Extracellular Matrix
Overview
In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, the molecules in the ECM maintain the structural integrity of tissue as well as the remarkable specific properties of certain tissues.
Composition of the Extracellular Matrix
The extracellular matrix (ECM) is commonly composed of ground substance, a gel-like fluid, fibrous components, and many structurally and functionally diverse...
In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, the molecules in the ECM maintain the structural integrity of tissue as well as the remarkable specific properties of certain tissues.
Composition of the Extracellular Matrix
The extracellular matrix (ECM) is commonly composed of ground substance, a gel-like fluid, fibrous components, and many structurally and functionally diverse...
01:42The Extracellular Matrix
Overview
01:26Extracellular Matrix
Unlike epithelial tissue, which is composed of cells closely packed with little or no extracellular space in between, connective tissue cells are dispersed in a matrix. This extracellular matrix (ECM) is composed of fibrous proteins like collagen, elastin, and fibronectin in a ground substance consisting of interstitial fluid, cell adhesion proteins, and proteoglycans. The proteoglycans form a gel-like material in the spaces between cells and provide hydration, buffering, binding, and force...
01:21Matrix Proteoglycans and Glycoproteins
Proteoglycans are extensively glycosylated proteins, commonly found in the extracellular matrix, interwoven with collagen fibers. Hyaline cartilage, the most common type of cartilage in the body, consists of short and dispersed collagen fibers associated with large amounts of proteoglycans. These proteoglycans have long negative charges that attract cations, which in turn attract water molecules. This influx of ions and water molecules swells up the proteoglycan like a water-soaked gel that can...
01:23Role of Matrix Metalloproteases in Degradation of ECM
Matrix metalloproteases (MMPs) are enzymes involved in the hydrolysis of proteins and glycoproteins of the extracellular matrix. MMPs are essential for the migration and proliferation of cells through the dense matrix network, throughout embryonic development, and throughout morphogenesis. The first MMP activity discovered was a collagenase in a tadpole's tail undergoing metamorphosis. The active collagen deposition and modifications lead to the morphogenesis of tadpoles into the adult body.
A...
A...
01:24Overview of Cell-Matrix Interactions
The extracellular matrix or ECM holds cells together to form a tissue and allows the cells within the tissue to communicate. ECM comprises proteins such as fibronectin, collagen, laminin, etc. The most abundant protein in this space is collagen. Collagen fibers are interwoven with carbohydrate-containing protein molecules called proteoglycans. ECM allows cell migration and provides a structural scaffold at cell adhesion that anchors the cell when the extracellular matrix proteins interact with...