Figure 6.
The cryptic fibrinlike β15-21 epitope is exposed in matrix-FBG fibrils that colocalize with FN fibrils. Confluent monolayers of HFFs were treated with purified plasma FBG at 40 μg/mL for 24 hours. FBG matrix fibrils were detected with MoAb T2G1 (red fluorescence), which recognizes the neo-NH2-terminus (β15-21 ) of the fibrin β chain, and FN matrix fibrils (green fluorescence) were detected with polyclonal antihuman FN IgG. Very few isolated fibrils of FN (green) or FBG (red staining) are found in the matrix; most FBG colocalizes with FN fibrils (yellow fluorescence), indicating that the cryptic β15-21 epitope is exposed in FBG matrix fibrils distributed along the length of FN matrix fibrils. Scale bar represents 25 μm.