Quantification of fibronectin matrix assembly sites using a novel ELISA assay.

Center for Cell Biology and Cancer Research, Albany Medical College, 47 New Scotland Avenue, Albany, New York 12208, USA.
Matrix Biology (Impact Factor: 3.65). 06/2007; 26(4):330-3. DOI: 10.1016/j.matbio.2006.12.004
Source: PubMed

ABSTRACT Binding of the N-terminus of fibronectin to assembly sites on the cell surface is an essential step in fibronectin fibrillogenesis. Fibronectin matrix assembly sites have customarily been quantified using an iodinated 70 kDa N-terminal fibronectin fragment. The 125I-70 K fragment is a less than ideal reagent because its preparation requires large amounts of plasma fibronectin and it has a fairly short shelf life. An additional limitation is that the cells responsible for binding the 125I-70 K cannot be quantified or identified directly but must be assessed in parallel cultures. To overcome these disadvantages, we developed an ELISA-based assay using a recombinant HA-tagged 70 K fragment. This assay allows for the simultaneous quantification and localization of matrix assembly sites on the surface of adherent cells.

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