FIGURE 2.

Matrix deposition of fibrillin-1, LTBP-1, and LTBP-4 by fibroblast cultures. Immunofluorescence, using antibodies specific for fibrillin-1 (pAb 9543) (A and G), LTBP-1 (pAb 8579) (B, E, and H), and LTBP-4 (pAb 2101) (C, F, and I), demonstrated incorporation of all three proteins into fibrillar matrices in wild type fibroblasts (A–C) grown for 9 days. In Fbn1 null fibroblasts (D–F) grown for 13 days, no matrix incorporation of LTBPs was visible (E and F), even though fibronectin fibrils were present in the Fbn1 null matrix (D). Fbn2 null fibroblasts (G–I), grown for 9 days, assemble fibrillin-1 positive fibrils (G) as well as LTBP-1 (H) and LTBP-4 (I) positive fibrils. Bar = 20 μm.