Abstract: The present invention relates to a method of growing a plurality of cells (110) to performance competence in a matrix forming agent (120) containing one or more density modifiers (130), characterized in that the cells are grown in a culture media supplemented with from 2-20% human plasma. It also relates to a biological component (100) comprising: i. a matrix forming agent (120), ii. a plurality of cells (110), and iii. one or more density modifiers (130), wherein at performance competence, the cells are present in the matrix forming agent at a density of at least 3×107 cells/ml.