Cartilage extracellular matrix proteins and associated transforming growth factor-beta complexes (Cartilage ECM-TGF-β complexes)

Cartilage extracellular matrix (ECM) proteins and associated transforming growth factor-beta (TGF-β) complexes function as a sophisticated regulatory system for maintaining articular cartilage integrity. The ECM acts as a biological scaffold and a reservoir, sequestering TGF-β in a latent state via covalent and non-covalent bonds with proteins such as Latent TGF-β Binding Proteins (LTBPs) and fibrillins (PubMed: 22278150). This sequestration is vital for preventing inappropriate signaling and ensuring that TGF-β is available for rapid activation during tissue repair or mechanical loading (PubMed: 24603329). In pathological conditions like osteoarthritis, the proteolytic degradation of ECM components—such as collagen type II and aggrecan—disrupts these complexes, leading to aberrant TGF-β signaling that promotes joint degeneration and inflammation (PubMed: 30107047). Therapeutic interventions focus on modulating the activation of these latent complexes, often by targeting the integrins or proteases responsible for releasing the active growth factor (PubMed: 28212733). By specifically addressing the ECM-bound pool of TGF-β, researchers hope to achieve localized therapeutic effects while minimizing the systemic side effects typically associated with global TGF-β antagonism. Overall, the interaction between the cartilage matrix and TGF-β represents a key checkpoint in joint homeostasis and a promising avenue for disease-modifying osteoarthritis drugs (DMOADs).

Other names

Cartilage ECM-TGF-beta signaling complexLatent TGF-beta complexes in cartilageECM-sequestered TGF-betaChondrocyte ECM-growth factor nicheTGF-beta-LTBP-ECM complex

Modulation of TGF-beta bioavailability through the inhibition of latent complex activation, stabilization of the extracellular matrix, or direct ligand neutralization.