Figure 5: ELISA analysis of the collagen II content of chondrogenic differentiated mesenchymal stem cell (MSC) aggregates after 21 days of culture under different conditions. The pellets were cultured with 0, 5, 10, 50, 100, or 200 ng/mL BMP7 with or without 10 ng/mL TGFβ1. The addition of 50 ng/mL BMP7 to the TGFβ1 containing culture medium showed the highest content of collagen II compared to other BMP7 concentrations with a significant difference between 10 ng/mL and 50 ng/mL BMP7 (). A BMP7 concentration dependent increase in collagen II content was detected under culture conditions without TGFβ1.