CD40-mediated immune cell activation enhances response to anti-PD-1 in murine intrahepatic cholangiocarcinoma

• Published in: Journal of hepatology Vol. 74; no. 5; pp. 1145 - 1154
• Main Authors: Diggs, Laurence P., Ruf, Benjamin, Ma, Chi, Heinrich, Bernd, Cui, Linda, Zhang, Qianfei, McVey, John C., Wabitsch, Simon, Heinrich, Sophia, Rosato, Umberto, Lai, Walter, Subramanyam, Varun, Longerich, Thomas, Loosen, Sven H., Luedde, Tom, Neumann, Ulf Peter, Desar, Sabina, Kleiner, David, Gores, Gregory, Wang, Xin Wei, Greten, Tim F.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2021; Elsevier Science Ltd
• Subjects: Agonists; Animal models; Animals; Antigen-presenting cell; Antigen-presenting cells; Antimetabolites, Antineoplastic - pharmacology; Apoptosis; CD4 antigen; CD40 agonist; CD40 antigen; CD40 Antigens - agonists; CD8 antigen; Cell activation; Cell culture; Cell death; Cell Line, Tumor; Chemotherapy; Cholangiocarcinoma; Cholangiocarcinoma - immunology; Cholangiocarcinoma - pathology; Cisplatin; Cisplatin - pharmacology; Dendritic cell; Dendritic cells; Dendritic Cells - immunology; Deoxycytidine - analogs & derivatives; Deoxycytidine - pharmacology; Drug Collateral Sensitivity; Effector cells; Flow cytometry; Gemcitabine; Immune checkpoint; Immune Checkpoint Inhibitors - pharmacology; Immunoglobulin G; Immunotherapy; Liver cancer; Liver Neoplasms - immunology; Liver Neoplasms - pathology; Lymphocytes; Lymphocytes T; Lymphocytes, Tumor-Infiltrating - drug effects; Macrophage; Macrophage Activation - immunology; Macrophage-Activating Factors - immunology; Macrophages; Metastases; Mice; Mice, Knockout; Myeloid cells; Natural killer cells; NK cell; PD-1 protein; PD-L1 protein; T cell; Tumor Microenvironment - drug effects; Tumor Microenvironment - immunology; Tumor-infiltrating lymphocyte; Tumors; CD40 agonist; Liver cancer; Dendritic cell; Immune checkpoint; T cell; Immunotherapy; NK cell; Antigen-presenting cell; Tumor-infiltrating lymphocyte; Cholangiocarcinoma; Macrophage
• ISSN: 0168-8278; 1600-0641
• DOI: 10.1016/j.jhep.2020.11.037

While cholangiocarcinomas (CCAs) commonly express programmed cell death 1 (PD-1) and its ligand (PD-L1), they respond poorly to immune checkpoint inhibitors (ICIs). We aimed to determine whether stimulating antigen-presenting cells, including macrophages and dendritic cells, using a CD40 agonist could improve this response. We compared treatment responses in subcutaneous, orthotopic, and 2 plasmid-based murine intrahepatic CCA (iCCA) models. Mice were treated for 4 weeks with weekly IgG control, a CD40 agonistic antibody, anti-PD-1, or the combination of both (anti-CD40/PD-1). Flow cytometric (FACS) analysis of lymphocytes and myeloid cell populations (including activation status) was performed. We used dendritic cell knockout mice, and macrophage, CD4+ and CD8+ T cell depletion models to identify effector cells. Anti-CD40/PD-1 was combined with chemotherapy (gemcitabine/cisplatin) to test for improved therapeutic efficacy. In all 4 models, anti-PD-1 alone was minimally efficacious. Mice exhibited a moderate response to CD40 agonist monotherapy. Combination anti-CD40/PD-1 therapy led to a significantly greater reduction in tumor burden. FACS demonstrated increased number and activation of CD4+ and CD8+ T cells, natural killer cells, and myeloid cells in tumor and non-tumor liver tissue of tumor-bearing mice treated with anti-CD40/PD-1. Depletion of macrophages, dendritic cells, CD4+ T cells, or CD8+ T cells abrogated treatment efficacy. Combining anti-CD40/PD-1 with gemcitabine/cisplatin resulted in a significant survival benefit compared to gemcitabine/cisplatin alone. CD40-mediated activation of macrophages and dendritic cells in iCCA significantly enhances response to anti-PD-1 therapy. This regimen may enhance the efficacy of first-line chemotherapy. Checkpoint inhibition, a common form of immune therapy, is generally ineffective for the treatment of cholangiocarcinoma. These tumors suppress the infiltration and function of surrounding immune cells. Stimulating immune cells such as macrophages and dendritic cells via the CD40 receptor activates downstream immune cells and enhances the response to checkpoint inhibitors. [Display omitted] •Cholangiocarcinoma tumors do not respond to anti-PD-1 monotherapy, as lymphocyte infiltration and activation are limited.•CD40 is highly expressed on macrophages and dendritic cells.•Treatment with a CD40 agonist impedes cholangiocarcinoma growth.•Combining a CD40 agonist with anti-PD-1 results in significantly lower tumor burden than either monotherapy alone.•This combination may enhance the efficacy of first-line chemotherapy.