Regulatory effect of acellular cartilage extracellular matrix on phenotype of mouse macrophage line / 中国组织工程研究

ABSTRACT

BACKGROUND: Previous studies have confirmed that the extracellular matrix of acellular cartilage can effectively promote the repair and regeneration of articular cartilage defects, and has a good repair effect, but its mechanism of promoting regeneration has not been elucidated. OBJECTIVE: To investigate the regulation of phenotypic polarization of mouse macrophage cell line by extracellular matrix scaffolds derived from pigs. METHODS: Using pig knee articular cartilage as raw material, the decellularized cartilage extracellular matrix scaffold was prepared by wet grinding, differential centrifugation, and freeze drying. The mouse RAW264.7 macrophage cell line was inoculated on the decellularized cartilage extracellular matrix scaffold to construct a cell-scaffold complex, which induced polarization in vitro for 4 days. Cell adhesion was observed using scanning electron microscopy, and cell growth was observed with dead/viable cells. Immunofluorescence staining was used to observe the expression of CD86, a characteristic surface marker of M1type macrophages, and CD206, a characteristic surface marker of M2-type macrophages, and to clarify the polarization induction. RESULTS AND CONCLUSION: (1) Scanning electron microscopy showed that the macrophages in the complex were originally round or quasi round, arranged along the tube of the scaffold, and widely distributed on the surface and internal structure of the scaffold. (2) Dead/live cell staining showed that most of the cells attached to the scaffold were living cells, with only a few dead cells. (3) Immunofluorescence staining showed that the M2 type macrophage marker CD206 in the complex was 80% highly expressed. The positive expression of CD86 the marker of M1 type macrophages was scarce. (4) The results show that the porcine-derived acellular cartilage extracellular matrix scaffold can induce polarized M0 type macrophages to repair M2 type macrophages.