A novel method for detecting p53 autoantibodies in sera of patients with NSCLC

Background and objective: Serum autoantibody detection is useful means for the early diagnosis and prognosis of cancer. So our objective was to synthesize peptide array to analyse p53 autoantibodies in the sera of patients with non small cell lung cancer (NSCLC). Methods: Cellulose-bound overlapping peptides (12 mers) derived from p53 wild type protein were synthesized using SOPTs synthesis technique by an AutoSpot robot -ASP SL (Intavis, Germany). The membrane was incubated with 1/400 dilutions of p53 monoclonal antibody (Sc-53394) to establish a new approach to detect p53 antibody, and the epitopes of the p53 monoclonal antibody is already known. We analysed the p53 autoantibodies from the sera of NSCLC and controls by peptide array and ELISA. Results: We synthesized on cellulose membranes twelve-amino-acid overlapping peptides which included all of the sequences of the polypeptide chain of p53. The p53 autoantibody was positive in seven cases of thirty patients' sera with NSCLC and was negative in sera of the controls, with the same result of ELISA. Conclusion: The peptide array could be applied not only to detect the autoantibodies in the sera of patients with lung cancer, but also to map the epitopes of the autoantibodies which might be useful for the early diagnosis and prognosis of cancer.