Exogenously produced FBG deposition in preformed matrix of fibroblasts. A549 cell conditioned media (A) or purified plasma FBG (B) was added to confluent monolayers of HFFs grown on glass coverslips and then cultured for 3 days. The cells were fixed and stained, nonpermeabilized (A through C), with MoAb J88B for FBG (A and B) and an MoAb for α-tubulin (C). Permeabilized HFFs were stained with the MoAb for α-tubulin (D). The bar in (D) represents 15 μm.