Methods for inducing an immune response to a tumor in a subject are disclosed herein. These methods include selecting a subject with a tumor and administering a therapeutically effective amount of apoptotic tumor cells conjugated to a CpG oligodexoynucleotide (ODN) to the subject. In some embodiments, the CpG ODN is a K-type or a D-type CpG ODN. Methods for treating a tumor in a subject are also disclosed herein. These methods include selecting a subject with a tumor and administering a therapeutically effective amount of apoptotic tumor cells conjugated to a CpG oligodexoynucleotide (ODN) to the subject. In some embodiments, the tumor cells are autologous. In additional embodiments, the tumor is a lymphoma, cervical cancer, prostate cancer, breast cancer, colon cancer or a lung cancer.