RESUMEN
Inflammation and tissue damage associated with pancreatitis can precede or occur concurrently with pancreatic ductal adenocarcinoma (PDAC). We demonstrate that in PDAC coupled with pancreatitis (ptPDAC), antigen-presenting type I conventional dendritic cells (cDC1s) are specifically activated. Immune checkpoint blockade therapy (iCBT) leads to cytotoxic CD8+ T cell activation and elimination of ptPDAC with restoration of life span even upon PDAC rechallenge. Using PDAC antigen-loaded cDC1s as a vaccine, immunotherapy-resistant PDAC was rendered sensitive to iCBT with elimination of tumors. cDC1 vaccination coupled with iCBT identified specific CDR3 sequences in the tumor-infiltrating CD8+ T cells with potential therapeutic importance. This study identifies a fundamental difference in the immune microenvironment in PDAC concurrent with, or without, pancreatitis and provides a rationale for combining cDC1 vaccination with iCBT as a potential treatment option.
Asunto(s)
Carcinoma Ductal Pancreático , Células Dendríticas , Inmunoterapia , Neoplasias Pancreáticas , Microambiente Tumoral , Animales , Ratones , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/uso terapéutico , Carcinoma Ductal Pancreático/terapia , Carcinoma Ductal Pancreático/inmunología , Linfocitos T CD8-positivos/inmunología , Células Dendríticas/inmunología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Ratones Endogámicos C57BL , Neoplasias Pancreáticas/terapia , Neoplasias Pancreáticas/inmunología , Pancreatitis/inmunología , Pancreatitis/terapia , Microambiente Tumoral/inmunologíaRESUMEN
Inflammation and tissue damage associated with pancreatitis can precede or occur concurrently with pancreatic ductal adenocarcinoma (PDAC). We demonstrate that in PDAC coupled with pancreatitis (ptPDAC), antigen-presenting type-I conventional dendritic cells (cDC1s) are specifically activated. Immune checkpoint blockade therapy (iCBT) leads to cytotoxic CD8 + T cell activation and eradication of ptPDAC with restoration of lifespan even upon PDAC re-challenge. Such eradication of ptPDAC was reversed following specific depletion of dendritic cells. Employing PDAC antigen-loaded cDC1s as a vaccine, immunotherapy-resistant PDAC was rendered sensitive to iCBT with a curative outcome. Analysis of the T-cell receptor (TCR) sequences in the tumor infiltrating CD8 + T cells following cDC1 vaccination coupled with iCBT identified unique CDR3 sequences with potential therapeutic significance. Our findings identify a fundamental difference in the immune microenvironment and adaptive immune response in PDAC concurrent with, or without pancreatitis, and provides a rationale for combining cDC1 vaccination with iCBT as a potential treatment option.
RESUMEN
Immune checkpoint blockade (ICB) has revolutionized cancer treatment, yet quality of life and continuation of therapy can be constrained by immune-related adverse events (irAEs). Limited understanding of irAE mechanisms hampers development of approaches to mitigate their damage. To address this, we examined whether mice gained sensitivity to anti-CTLA-4 (αCTLA-4)-mediated toxicity upon disruption of gut homeostatic immunity. We found αCTLA-4 drove increased inflammation and colonic tissue damage in mice with genetic predisposition to intestinal inflammation, acute gastrointestinal infection, transplantation with a dysbiotic fecal microbiome, or dextran sodium sulfate administration. We identified an immune signature of αCTLA-4-mediated irAEs, including colonic neutrophil accumulation and systemic interleukin-6 (IL-6) release. IL-6 blockade combined with antibiotic treatment reduced intestinal damage and improved αCTLA-4 therapeutic efficacy in inflammation-prone mice. Intestinal immune signatures were validated in biopsies from patients with ICB colitis. Our work provides new preclinical models of αCTLA-4 intestinal irAEs, mechanistic insights into irAE development, and potential approaches to enhance ICB efficacy while mitigating irAEs.
Asunto(s)
Colitis , Interleucina-6 , Ratones , Animales , Calidad de Vida , Colitis/patología , Inmunoterapia , InflamaciónRESUMEN
Plasmacytoid dendritic cells (pDCs) are specialized type I interferon (IFN-I) producing cells that promote anti-viral immune responses and contribute to autoimmunity. Development of pDCs requires the transcriptional regulator E2-2 and is opposed by inhibitor of DNA binding 2 (Id2). Prior work indicates Id2 is induced in pDCs upon maturation and may affect pDC IFN-I production via suppression of E2-2, suggesting an important yet uncharacterized role in this lineage. We found TLR7 agonists stimulate Id2 mRNA and protein expression in pDCs. We further show that transcriptional activation of Id2 is dependent on the E2 ubiquitin-conjugating enzyme Ubc13, but independent of IFN-I signaling in response to TLR7 agonist stimulation. Nonetheless, conditional Id2 depletion in pDCs indicates Id2 is dispensable for TLR7 agonist-induced maturation and inhibition of E2-2 expression. Thus, we identify new mechanisms of Id2 regulation by Ubc13, which may be relevant for understanding Id2 gene regulation in other contexts, while ruling out major roles for Id2 in pDC responses to TLR7 agonists.
Asunto(s)
Interferón Tipo I , Receptor Toll-Like 7 , Células Dendríticas , Regulación de la Expresión Génica , Interferón Tipo I/metabolismo , Receptor Toll-Like 7/metabolismoRESUMEN
Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Our previous studies demonstrated a toll-like receptor 4 (TLR4) and C-type lectin receptor (CLR; Mincle/MCL) agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6'-dicorynomycolate (TDCM) effectively inhibits peritoneal tumor growth and ascites development through a mechanism dependent upon B1a cell-produced natural IgM, complement, and phagocytes. In the current study, we investigated the requirement for TLR4 and Fc receptor common γ chain (FcRγ), required for Mincle/MCL signaling, in the MPL/TDCM-elicited response. MPL/TDCM significantly increased macrophages and Ly6Chi monocytes in the peritoneal cavity of both TLR4-/- and FcRγ-/- mice, suggesting redundancy in the signals required for monocyte/macrophage recruitment. However, B1 cell activation, antibody secreting cell differentiation, and tumor-reactive IgM production were defective in TLR4-/-, but not FcRγ-/- mice. TRIF was required for production of IgM reactive against tumor- and mucin-related antigens, but not phosphorylcholine, whereas TLR4 was required for production of both types of reactivities. Consistent with this, B1 cells lacking TLR4 or TRIF did not proliferate or differentiate into tumor-reactive IgM-producing cells in vitro and did not reconstitute MPL/TDCM-dependent protection against peritoneal carcinomatosis in CD19-/- mice. Our results indicate a TLR4/TRIF-dependent pathway is required by B1 cells for MPL/TDCM-elicited production of protective tumor-reactive natural IgM. The dependency on TRIF signaling for tumor-reactive, but not phosphorylcholine-reactive, IgM production reveals unexpected heterogeneity in TLR4-dependent regulation of natural IgM production, thereby highlighting important differences to consider when designing vaccines or therapies targeting these specificities.
Asunto(s)
Proteínas Adaptadoras del Transporte Vesicular/fisiología , Subgrupos de Linfocitos B/inmunología , Factores Cordón/administración & dosificación , Inmunoglobulina M/inmunología , Lípido A/análogos & derivados , Neoplasias Peritoneales/inmunología , Receptor Toll-Like 4/fisiología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Subgrupos de Linfocitos B/efectos de los fármacos , Lípido A/administración & dosificación , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor 88 de Diferenciación Mieloide/fisiología , Neoplasias Peritoneales/metabolismo , Neoplasias Peritoneales/patologíaRESUMEN
Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Our previous study demonstrated a Toll-like receptor and C-type lectin receptor agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6'-dicorynomycolate (TDCM) effectively inhibits tumor growth and ascites development following TA3-Ha and EL4 challenge through a mechanism dependent on B-1a cell-produced natural IgM and complement. In this study, we investigated additional players in the MPL/TDCM-elicited response. MPL/TDCM treatment rapidly increased type I IFN levels in the peritoneal cavity along with myeloid cell numbers, including macrophages and Ly6Chi monocytes. Type I IFN receptor (IFNAR1-/-) mice produced tumor-reactive IgM following MPL/TDCM treatment, but failed to recruit Ly6C+ monocytes and were not afforded protection during tumor challenges. Clodronate liposome depletion of phagocytic cells, as well as targeted depletion of Ly6C+ cells, also ablated MPL/TDCM-induced protection. Cytotoxic mediators known to be produced by these cells were required for effects. TNFα was required for effective TA3-Ha killing and nitric oxide was required for EL4 killing. Collectively, these data reveal a model whereby MPL/TDCM-elicited antitumor effects strongly depend on innate cell responses, with B-1a cell-produced tumor-reactive IgM and complement pairing with myeloid cell-produced cytotoxic mediators to effectively eradicate tumors in the peritoneal cavity.
Asunto(s)
Antígenos Ly/metabolismo , Factores Cordón/farmacología , Interferón Tipo I/metabolismo , Lectinas Tipo C/agonistas , Lípido A/análogos & derivados , Neoplasias Peritoneales/tratamiento farmacológico , Receptores Toll-Like/agonistas , Adyuvantes Inmunológicos/farmacología , Animales , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proliferación Celular , Quimioterapia Combinada , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Lípido A/farmacología , Linfoma/tratamiento farmacológico , Linfoma/metabolismo , Linfoma/patología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias Peritoneales/metabolismo , Neoplasias Peritoneales/secundario , Fagocitos , Receptor de Interferón alfa y beta/fisiología , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Activating the antitumor immune response in the characteristically immune-suppressive peritoneal environment presents a potential strategy to treat this disease. In this study, we show that a toll-like receptor (TLR) and C-type lectin receptor (CLR) agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6'-dicorynomycolate (TDCM) effectively inhibits tumor growth and ascites development in a mouse model of aggressive mammary cancer-induced peritoneal carcinomatosis. MPL/TDCM treatment similarly inhibited peritoneal EL4 tumor growth and ascites development. These effects were not observed in mice lacking B cells or mice lacking CD19, which are deficient in B-1a cells, an innate-like B-cell population enriched in the peritoneal cavity. Remarkably, adoptive transfer of B-1a cells, but not splenic B cells from WT mice, restored MPL/TDCM-induced protection in mice with B-cell defects. Treatment induced B-1 cells to rapidly produce high levels of natural IgM reactive against tumor-associated carbohydrate antigens. Consistent with this, we found significant deposition of IgM and C3 on peritoneal tumor cells as early as 5 days post-treatment. Mice unable to secrete IgM or complement component C4 were not protected by MPL/TDCM treatment, indicating tumor killing was mediated by activation of the classical complement pathway. Collectively, our findings reveal an unsuspected role for B-1 cell-produced natural IgM in providing protection against tumor growth in the peritoneal cavity, thereby highlighting potential opportunities to develop novel therapeutic strategies for the prevention and treatment of peritoneal metastases. SIGNIFICANCE: This work identifies a critical antitumor role for innate-like B cells localized within the peritoneal cavity and demonstrates a novel strategy to activate their tumor-killing potential.See related commentary by Tripodo, p. 5.