Quantification of extracellular matrix components in immunolabeled tissue samples

In recent years, the interaction between cells and the extracellular matrix (ECM) has become a new focus in understanding tissue morphogenesis, regeneration, and disease. However, the lack of specific techniques to study the ECM composition in preserved tissue structures remains a major obstacle to explaining ECM changes in response to extrinsic stimuli. To overcome this, we propose a novel strategy that uses multidimensional fluorescence microscopy and computational tools to quantify ECM composition in immunolabeled tissues and/or cell-derived matrices (CDM). This approach includes a detailed protocol for densitometric fluorescence calibration and procedures for image acquisition, processing, and automated quantification. Using this method, we present new data comparing collagen types I, III, and IV, and fibronectin contents in various tissues. These results emphasize the importance of studying ECM compositionin situunder both normal homeostatic and disease conditions.Graphical abstract