Title : IgG and IgM antibody markers for immune monitoring in therapeutic cancer vaccine
Abstract:
The WT1 gene is an oncogene overexpressed in leukemia and various types of solid cancers. WT1 gene product is highly immunogenic and a promising target for cancer immunotherapy. We have developed a WT1 peptide-based therapeutic cancer vaccine and shown its clinical potential in clinical trials for various cancers. Therapeutic cancer vaccine induces tumor-associated antigen-specific immune responses to control tumors. One primary goal of immune monitoring is the detection of the induction of anti-tumor immune responses against target antigens after the start of vaccination. We have shown that IgG antibody production against vaccinated WT1 peptide is correlated with a favorable prognosis. This favorable prognostic correlation could be explained by the CD4 T-cell activity that is detected by the IgG production, where the class switch from IgM to IgG requires the help of CD4 T cells. Recently, we found the production of IgM antibodies against WT1 peptide before vaccination. Since the production of IgM antibodies does not require the help of CD4 T cells, WT1 peptide IgM antibodies could be correlated with anti- or pro-tumor immune responses of B cells. This presentation focuses on IgG and IgM antibody markers as immune monitoring tools in therapeutic cancer vaccines.
