matrix gla protein  (Atrix Laboratories Inc)

Journal: bioRxiv

Article Title: A Tough Biointerface in Human Knee Empowered by Dynamic Phase-transforming Minerals in Collagenous Matrix

doi: 10.1101/2024.08.03.606023

Figure Lengend Snippet: ( A ) Schematic illustration of the experimental procedure of proteomic analysis. ( B ) Classification of interface-enriched proteins based on functions described in Genecards Database. ( C ) Volcano plots of protein expression differences between interface and bone, and interface and root. Proteins with statistically significant differences in expression were colored in orange (significantly higher in interface) and blue (significantly lower in interface) ( p adjusted value < 0.05, fold change > 2). ( D ) Immunofluorescent staining of MGP at the S-H interface. ( E ) MGP protein expression profile across the S-H interface quantified using fluorescent signal intensity which increased in the mineralized tissue region and S-H interface (denoted by dashed line). ( F ) Functional verification of MGP’s role as a mineralization inhibitor through in vitro mineralization using nano-ACP. TEM images showed the increase in HAP crystals in the non-treated group was less than in the MGP-treated group on day 1 and day 3. Inlets revealed diffraction patterns of associated areas. ( G ) Quantification of HAP crystal density in TEM snapshots (n=5) of MGP-treated and non-treated groups. Statistical significance is illustrated as: *p ≤ 0.05; **p ≤ 0.01; ***p ≤ 0.001. Abbreviations: LC-MS/MS, liquid chromatography−tandem mass spectrometry; MGP, matrix Gla protein.

Article Snippet: 200-mesh golden grids with a carbon support film were added with 3 μL recombinant matrix gla protein (MGP) (100 μg/mL, CUSABIO, China) diluted with deionized water and the control group was added with 3 μL deionized water, and both were incubated for 20 minutes at room temperature.

Techniques: Expressing, Staining, Functional Assay, In Vitro, Liquid Chromatography with Mass Spectroscopy, Liquid Chromatography, Mass Spectrometry

Journal: bioRxiv

Article Title: A Tough Biointerface in Human Knee Empowered by Dynamic Phase-transforming Minerals in Collagenous Matrix

doi: 10.1101/2024.08.03.606023

Figure Lengend Snippet: The left panel illustrates the hierarchical structure of the meniscus root-bone interface under static condition. From macroscale to nanoscale: histological zones of the root-bone interface; transformation of mineral aggregates from ACP, immature HAP to HAP alongside mineralization of collagen fibrils; ACP, immature HAP and collagen form molecular bonds with collagen fibrils, while MGP protein and proteoglycans interact with the mineral aggregates and collagen to mediate mineralization. The right panel demonstrates the multiscale mechanical response upon mechanical loading. From macroscale to nanoscale: soft tissue responds to stress first via fiber stretching and straightening while the interface responds last, and cracks would be deflected or blunted; the ACP and immature aggregates dissipate stress (denoted by “E”) through sliding in the interfibrillar space, and crack would be arrested by stiff mineral aggregates; bonds among mineral aggregates and collagen could break for energy dissipation, and new bonds formation could occur simultaneously. Abbreviations: LR, ligamentous root; FC, fibrocartilage; MFC; mineralized fibrocartilage; ACP, amorphous calcium phosphate; HAP, hydroxyapatite; MGP, matrix gla protein.

Article Snippet: 200-mesh golden grids with a carbon support film were added with 3 μL recombinant matrix gla protein (MGP) (100 μg/mL, CUSABIO, China) diluted with deionized water and the control group was added with 3 μL deionized water, and both were incubated for 20 minutes at room temperature.

Techniques: Transformation Assay