Molecular probes displaying the LNLPHG and RFSAFY peptide sequences showed the greatest binding affinity to fibronectin fibers and the greatest efficiency in discriminating between relaxed and strained fibers. On extracellular matrix assembled by primary lung fibroblasts, LNLPHG preferentially attached to relaxed fibronectin fibers (top row), whereas RFSAFY bound to strained fibers (bottom row). (Scale bar: 20 microns) (Credit: Thomas Barker)
