by The extracellular matrix: more than just scaffolding
The extracellular matrix (ECM) was long thought to simply provide structural support and framework for cells. New research over the past few decades has revealed that the ECM plays a far more dynamic and complex role in numerous biological processes.
What is the extracellular matrix?
The ECM refers to the non-cellular component present outside cells in most animal tissues and that usually provides structural support to surrounding cells. It is produced by resident cells like fibroblasts, and its main components are collagens, elastin, fibronectin and proteoglycans. Along with providing mechanical support, the ECM also acts as a reservoir for growth factors and cytokines that influence cell behavior.
Role of ECM in tissue development and remodeling
The composition and properties of the ECM vary significantly between different tissue types, and this tailored ECM helps guide tissue development and remodeling. During fetal development, interactions between cells and the developing ECM scaffold are crucial for differentiation, migration and appropriate tissue architecture. Changes in ECM composition also drive tissue repair, regeneration and wound healing in adults. Precise spatial and temporal deposition of specialized ECM components allows remodeling of tissues in response to physiological needs or damage.
ECM acts as a signaling hub
Current research highlights that the Extracellular Matrix acts as a signaling depot that modulates numerous cellular functions and behaviors beyond passive support. Embedded proteoglycans and glycoproteins in the ECM sequester growth factors and cytokines in bioavailable form. Specific ECM-cell interactions via integrin adhesion receptors triggers downstream signaling cascades that influence cell proliferation, survival and phenotype. The dynamic interplay between ECM biochemistry and mechanics regulates diverse processes like stem cell differentiation, immune cell migration and tumor pathogenesis.
Role of ECM in stem cell niche and regeneration
The unique ECM microenvironment or niche plays a key role in maintaining adult stem cells in a quiescent or primed state. Changes in the niche ECM biophysical and biochemical cues precisely regulate stem cell self-renewal or shift their fate towards differentiation and regeneration. In some tissues with remarkable regenerative abilities like salamander limbs, the ECM acts as an information superhighway carefully orchestrating complex cellular activities during regeneration. Deciphering ECM dynamics in native stem cell niches is crucial for advances in regenerative medicine.
ECM alterations in disease
ECM remodeling is a tightly regulated process, and abnormal changes in its composition and structure contribute to myriad pathological conditions. Excessive ECM deposition underlies fibrosis and organ scarring. Aberrant ECM biochemistry promotes epithelial to mesenchymal transition, a key event in cancer invasion and metastasis. Defective ECM also associates with cardiovascular disorders, musculoskeletal diseases and impaired wound healing. Elucidating ECM-disease connections provides new avenues for treatment and prevention of major human morbidities.
ECM as a biomedical tool and therapeutic target
Given its diverse roles, the ECM has emerged as an important factor to consider in tissue engineering, regenerative therapies and drug delivery approaches. Biomaterial scaffolds mimicking natural ECM properties aid new tissue growth from stem cells or guide host cell infiltration. ECM-derived bioactive factors may hold promise as pro-regenerative therapies. Novel ECM-based hydrogels allow on-demand drug release or minimally invasive cell delivery. Modulating ECM remodeling through small molecules, biologics or genetic tools shows therapeutic potential for fibrosis, cancer and degenerative diseases. Continued mechanistic insights will spur development of ECM-focused precision medicines.
*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
