Gels of polysaccharides and fibrous proteins fill the interstitial space and act as a compression buffer against the stress placed on the ECM.

[9] Some single-celled organisms adopt multicellular biofilms in which the cells are embedded in an ECM composed primarily of extracellular polymeric substances (EPS).

Glycosaminoglycans (GAGs) are carbohydrate polymers and mostly attached to extracellular matrix proteins to form proteoglycans (hyaluronic acid is a notable exception; see below).

It occurs as a proteoglycan (PG) in which two or three HS chains are attached in close proximity to cell surface or ECM proteins.

Hyaluronic acid in the extracellular space confers upon tissues the ability to resist compression by providing a counteracting turgor (swelling) force by absorbing significant amounts of water.

Disorders such as Ehlers Danlos Syndrome, osteogenesis imperfecta, and epidermolysis bullosa are linked with genetic defects in collagen-encoding genes.

Similar to ECM bioscaffolds, MBVs can modify the activation state of macrophages and alter different cellular properties such as; proliferation, migration and cell cycle.

Fibronectins also help at the site of tissue injury by binding to platelets during blood clotting and facilitating cell movement to the affected area during wound healing.

This property is primarily dependent on collagen and elastin concentrations,[4] and it has recently been shown to play an influential role in regulating numerous cell functions.

[26] Inhibition of nonmuscle myosin II blocks most of these effects,[25][23][22] indicating that they are indeed tied to sensing the mechanical properties of the ECM, which has become a new focus in research during the past decade.

[27] Although the mechanism by which this is done has not been thoroughly explained, adhesion complexes and the actin-myosin cytoskeleton, whose contractile forces are transmitted through transcellular structures are thought to play key roles in the yet to be discovered molecular pathways.

In particular, naive mesenchymal stem cells (MSCs) have been shown to specify lineage and commit to phenotypes with extreme sensitivity to tissue-level elasticity.

MSCs placed on soft matrices that mimic the brain differentiate into neuron-like cells, showing similar shape, RNAi profiles, cytoskeletal markers, and transcription factor levels.

The term was coined by Lo CM and colleagues when they discovered the tendency of single cells to migrate up rigidity gradients (towards more stiff substrates)[23] and has been extensively studied since.

The molecular mechanisms behind durotaxis are thought to exist primarily in the focal adhesion, a large protein complex that acts as the primary site of contact between the cell and the ECM.

Due to its diverse nature and composition, the ECM can serve many functions, such as providing support, segregating tissues from one another, and regulating intercellular communication.

[25] Cells actively sense ECM rigidity and migrate preferentially towards stiffer surfaces in a phenomenon called durotaxis.

[23] They also detect elasticity and adjust their gene expression accordingly, which has increasingly become a subject of research because of its impact on differentiation and cancer progression.

Upon matrix degradation, hyaluronan fragments are released to the extracellular space, where they function as pro-inflammatory molecules, orchestrating the response of immune cells such as microglia.

The attachment of fibronectin to the extracellular domain initiates intracellular signalling pathways as well as association with the cellular cytoskeleton via a set of adaptor molecules such as actin.

Although the mechanism of action by which extracellular matrix promotes constructive remodeling of tissue is still unknown, researchers now believe that Matrix-bound nanovesicles (MBVs) are a key player in the healing process.

It is currently being used regularly to treat ulcers by closing the hole in the tissue that lines the stomach, but further research is currently being done by many universities as well as the U.S. Government for wounded soldier applications.

Extracellular matrix coming from pig small intestine submucosa are being used to repair "atrial septal defects" (ASD), "patent foramen ovale" (PFO) and inguinal hernia.

The cell wall comprises multiple laminate layers of cellulose microfibrils embedded in a matrix of glycoproteins, including hemicellulose, pectin, and extensin.

[15] The extracellular matrix functionality of animals (Metazoa) developed in the common ancestor of the Pluriformea and Filozoa, after the Ichthyosporea diverged.