ANTIGENIC PROPERTIES OF THE 2ND LOOP OF TRANSFORMING GROWTH FACTOR-ALPHA BY SYNTHETIC PEPTIDES

We describe synthesis and immunological properties of peptides constru cted based on the second loop of TGF-alpha. The peptides were synthesi zed manually using a standard solid-phase Boc protocol. Sulfhydryl gro ups were protected as acetamidomethyl derivatives during the synthesis and the disulfide bridges were formed at high dilution by oxidation w ith iodine in the presence of glutathione. In ELISA assays antibodies to the peptides were inhibited by the native hormone to various extent s. In addition, two peptides reacted well with a polyclonal antibody t o TGF-alpha, but this reaction was only slightly inhibited by TGF-alph a in solution.