FIGURE 8.

mAb 689 binds to an epitope in EGF4 in all three fibrillins. When tested in ELISA (A), mAb 689 reacted with rF301, the recombinant fibrillin-3 peptide used to generate this mAb. mAb 689 also reacted with recombinant fibrillin-1 and -2 peptides containing EGF4 but not with peptides missing EGF4. Of the four domains contained in rF301, rF47 contains only EGF4, and mAb 689 reacted well with rF47. Similarly, mAb 689 reacted well with rF20, a fibrillin-1 recombinant peptide whose N-terminal domain is EGF4 (data not shown). B, identical residues in the amino acid sequences of EGF4 in fibrillin-1, -2, and -3 are shaded.