The plates were then tilted slightly to aspirate the PBS carefully using a Pasteur pipette. 1 mL of 4% PFA was added to each well, to fix for 20 min at room temperature. It was then carefully pipetted away and washed with PBS twice. 4% (wt/vol) BSA blocking solution was freshly prepared by diluting 2 g of BSA in 50 mL of PBS. This solution was filter-sterilised through a 0.45-µm filter before adding 2 mL to each well for 1 hour at room temperature. By using tweezers and a pipette tip, each coverslip was gently removed from the wells. Excess solution was dried off and they were then placed in a humidified chamber. 100 µL of the primary antibodies in BSA solution anti-collagen-I, and anti-fibronectin, 1/1000 dilution were added to each coverslip and the humidified chamber was left at