Collagen II Antibody - #AF0135

Fig. 3. Regulation of apoEVs on chondrocytes and ATDC5 cells. (a) Representative images showing the cellular uptake of DiD-labeled apoEVs (red) by chondrocytes. (Scale bar, 20 μm) (b) Representative images of type II collagen (red) in chondrocytes. (Scale bar, 50 μm) (c) Expression of chondrogenic genes measured by qRT-PCR. (n = 3) (d) Content of total collagen detected by Sirius red. (n = 4) (e) GO analysis showed that upregulated proteins in Mφ-apoEVs and OC-apoEVs were enriched in cartilage matrix associated terms. (f) KEGG pathway analysis showed that enriched proteins in Mφ-apoEVs and OC-apoEVs were more closely associated with extracellular matrix organization. (Fold change >1.5, P value < 0.05) (*p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001).

Fig. 1 CCO exhibits characteristics of articular cartilage and delays the process of ossification. (A) SO, staining of the CEP. CEP had a quasi-spherical shape. (B) DAPI staining. CEP decellularization of nuclei. (C) DNA content, GAG content, and Total collagen content measurement. CEP was decellularized, preserving a significant amount of GAG and collagen. (D) Cell viability and cytotoxicity assay using Calcein/PI at D1, D3, and D7, with live cells shown in green and dead cells in red. CEP exhibits good biocompatibility. (E) CCK-8 assay at D1, D3, and D7. CEP can promote the proliferation of BMSCs. (F) HE and AB staining of CO and CCO on days 7, 14, and 21. CCO can generate a greater amount of cartilage matrix. (G) Immunofluorescence images for COL2, ACAN in CO and CCO at days 14, with blue representing DAPI and red representing the target proteins. The cartilage markers COL2 and ACAN are expressed at higher levels in CCO. (H)Immunohistochemical images for PRG4 in CO and CCO at days 14 and Immunofluorescence images for COLX in CO and CCO at days 21 with blue representing DAPI and red representing the target proteins. CCO exhibits high expressions of the articular cartilage-specific marker PRG4 and low expressions of the hypertrophic cartilage marker COLX. (I) The mRNA expression of cartilage genes SOX9, COL2, and ACAN, as well as the hypertrophic cartilage gene COLX, was assessed in CO and CCO at 0, 7, 14, and 21 days. Both CCO and CO reached peak cartilage expression in 14 days, after which the expression of hypertrophy-related genes increased. However, CCO demonstrated superior cartilage formation compared to CO, with a delayed hypertrophic process. All experiments were repeated three times. ns p > 0.05, *0.01