PREPARATION AND CHARACTERIZATION OF ANTIBODIES WITH SPECIFICITY FOR THE AMINO-TERMINAL TETRAPEPTIDE SEQUENCE OF THE PLATELET-DERIVED CONNECTIVE-TISSUE ACTIVATING PEPTIDE-III

  • 1 January 1985
    • journal article
    • research article
    • Vol. 10  (3) , 395-404
Abstract
Antisera selective reactive with the N-terminal tetrapeptide sequence of the platelet-derived connective tissue activating peptide-III mitogen were prepared [from outdated blood bank platelets] and characterized. Solid phase synthesized Z-Asn-Leu-Ala-Lys(Z)-OH tetrapeptide representing the N-terminus of the mitogen was used as an immunogen after carbodiimide mediated coupling to methylated bovine serum albumin carrier and subsequent removal of Z groups. Anti-tetrapeptide sera demonstrated cross-reactivity to the mitogen but not .beta.-thromboglobulin, fibroblast growth factor, or epidermal growth factor, and a limited cross-reactivity to parathyroid hormone. The N-termial sequence of the mitogen may be accessible for binding with antibody and the antitetrapeptide sera provide a reagent for the selective measurement of biologically active mitogen in the presence of structurally similar .beta.-thromboglobulin. Computer analysis of amino acid sequences revealed that few proteins contain the Asn-Leu-Ala-Lys sequence and of those that do, many are retroviral proteins or transforming polyproteins.