(A) Morphology of human BMSCs on BS, BS3, and BS5 with actin stained in green and nuclei stained in blue by DAPI after being cultured for 1 day and 5 days. BMSCs were adherent more strongly and proliferated faster on BS5. (B) MTS assay of BMSCs proliferation on BS, BS3 and BS5 after being cultured for 1 day and 5 days. (C) Assay of the enzymatic activity of the early osteogenic differentiation marker, alkaline phosphatase (ALP), showing that BS3 and BS5 promoted the osteogenic differentiation of BMSCs in comparison to the BS. In addition, BS5 shows better capability in promoting the osteogenic differentiation of BMSCs than the BS3.* p< 0.05, ** p< 0.01. BS, BS3, and BS5 denote B. mori sericin, and B. mori sericin mineralized for 3 day and 5 days, respectively.