Pancreatic ductal
adenocarcinoma (PDAC) represents 3% of all
cancer cases and 7% of all
cancer deaths in the United States. Late diagnosis and inadequate response to standard
chemotherapies contribute to an unfavorable prognosis and an overall 5-year survival rate of less than 10% in PDAC. Despite recent advances in
tumor immunology,
tumor-induced immunosuppression attenuates the
immunotherapy response in PDAC. To date, studies have focused on
IgG-based therapeutic strategies in PDAC. With the recent interest in
IgE-based
therapies in multiple solid
tumors, we explored the MUC1-targeted
IgE potential against
pancreatic cancer. Our study demonstrates the notable expression of FceRI (receptor for
IgE antibody) in
tumors from PDAC patients. Our study showed that administration of MUC1 targeted-
IgE (mouse/human chimeric anti-MUC1.
IgE) antibody at intermittent levels in combination with checkpoint inhibitor (anti-PD-L1) and TLR3 agonist (PolyICLC) induces a robust antitumor response that is dependent on NK and CD8 T cells in pancreatic
tumor-bearing mice. Subsequently, our study showed that the
antigen specificity of the
IgE antibody plays a vital role in executing the antitumor response as nonspecific
IgE, induced by
ovalbumin (OVA), failed to restrict
tumor growth in pancreatic
tumor-bearing mice. Utilizing the OVA-induced allergic
asthma-PDAC model, we demonstrate that allergic phenotype induced by OVA cannot restrain pancreatic
tumor growth in orthotopic
tumor-bearing mice. Together, our data demonstrate the novel
tumor protective benefits of
tumor antigen-specific
IgE-based
therapeutics in a preclinical model of
pancreatic cancer, which can open new avenues for future clinical interventions.