Patients with cervical cancer produce an antibody response to an HSV-inducible tumour-specific cell polypeptide

Anti-sera raised against HSV-2-infected cells (WI) and the sera of animals bearing tumours (TBS) to HSV-2 transformed cells contain antibodies to a set of tumour-specific cell-coded polypeptides. The specificity of these polypeptides for tumour cells is monitored by the ability of [35S]-L-methionine labelled proteins to be immunoprecipitated by these anti-sera, in contrast to control cells from which the polypeptides are not precipitated. The polypeptides which share an epitope and are co-precipitated are of MWs 90,000 (a doublet), 40,000 and 32,000. The upper 90,000-MW polypeptide (U90) is induced by HSV-2 infection. This communication deals with the 40,000-MW polypeptide which was shown to be immunoprecipitated by TBS and a monoclonal antibody (MAb) raised to the DNA-binding proteins of HSV-2-infected cells. Immunological and biochemical studies reveal that the 40,000-MW protein which is immunoprecipitated comprises more than one polypeptide, and that the proteins may need to interact to produce the peptide pattern specific for the tumour form of the immunoprecipitated 40,000-MW protein. WI antisera and TBS both recognise antigens specific for tumour cells in sections of cervical-carcinoma tissue. Sera from patients with cancer of the cervix contain antibodies to a cell-coded polypeptide of MW 40,000, which by peptide analysis is indistinguishable from the 40,000-MW polypeptide induced by HSV-2 infection and immunoprecipitated by WI and TBS.