Screening of short peptides binding to cell surface interleukin-2 receptor alpha chain / 南方医科大学学报

ABSTRACT

<p><b>OBJECTIVE</b>To screen and characterize the short peptides which bind specifically to interleukin-2 (IL-2) receptor alpha chain (IL-2Ralpha) for acquisition of small antagonists for blocking the binding of IL-2 with IL-2Ralpha.</p><p><b>METHODS</b>12-mer phage displayed peptide library was screened with the target cells of MT-2 cells which expressed IL-2Ralpha at high levels. The binding phage clones were eluted by anti-IL-2Ralpha monoclonal antibody. After 3 rounds of screening, the positive phage clones were identified by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, and the amino acid sequences of the positive clones were deduced from the DNA sequences.</p><p><b>RESULTS</b>Seven positive clones were screened out of the 17 phage clones bound to MT-2 cells. The positive clone M15 could bind specifically to MT-2 cell and PHA-activated peripheral blood monouclear cells. Amino acid sequence analysis identified 6 sequences, all of which contained hydrophilic residues, and 5 of these 6 sequences included Tyr, Phe and Leu conservative residues.</p><p><b>CONCLUSION</b>The peptide sequences containing Tyr, Phe conservative residues identified in this study can bind to cell surface IL-2Ralpha.</p>