scholarly journals P09.15 Targeting the stroma to enhance effector memory T cell infiltration and anti-tumor response to anti-PD1 antibody in pancreatic ductal adenocarcinoma

2020 ◽  
Vol 8 (Suppl 2) ◽  
pp. A59.2-A60
Author(s):  
A Osipov ◽  
L Zheng
Keyword(s):  
T Cell ◽  
Myeloid Cells ◽  
Myeloid Cell ◽  
Cxcr4 Expression ◽  
Cell Infiltration ◽  
Ductal Adenocarcinoma ◽  
Effector Memory ◽  
Cell Populations ◽  
Memory T Cell ◽  
T Cell Infiltration

BackgroundPancreatic ductal adenocarcinoma (PDAC) is resistant to immune checkpoint inhibition. One of the major resistance mechanisms is attributed to myeloid cells as an immunosuppressive element within the stroma of PDAC. It has been reported that focal adhesion kinase inhibitor (FAKi) can suppress immunosuppressive myeloid cells such as tumor associated macrophages (TAMs) and myeloid derived suppressor cells (MDSC), consequently sensitizing tumor to anti-PD1 antibody in mouse models of PDAC. Our group has previously shown in a murine model that targeting the stroma via PEGylated recombinant human hyaluronidase (PEGPH20) enhanced the anti-tumor activity of the whole cell vaccine (GVAX) by targeting CXCR4-expressing myeloid cells and led to an increase in infiltration of CCR7- effector memory T cell subsets. Here, we evaluate the hypothesis that FAK expressing myeloid cell subsets modulate T cell infiltration in human PDAC and FAKi can synergize with PEGPH20 by targeting myeloid cells in PDAC.Material and MethodsResected human PDAC tissue specimens treated with GVAX and anti-PD1 therapy was used to assess FAK expression in myeloid cell subsets and its impact on T cell infiltration. A sequential staining and stripping multiplex IHC technique that incorporates 28 myeloid and lymphoid biomarkers, as well as phosphorylated FAK (pFAK) combined with computational image processing was used to assess myeloid cell populations, T cell infiltration and FAK expression.An established murine model of metastatic PDAC treated with and without anti-PD1 therapy was used to assess the synergy and immune-modulating effect of FAKi and stromal degradation of hyaluronan via PEGPH20.ResultsIn human PDAC, FAK is widely expressed in TAMs and neutrophils. Increased FAK expression is associated with increased CXCR4 expression. Lower pFAK density in neutrophils and M2 TAMs, but not lower pFAK density in M1 TAMs, is associated with higher CD8+ T cell infiltration.FAKi and combination of FAKi with anti-PD1 extends survival in the mouse metastasis model of PDAC. Adding PEGPH20 to FAKi and anti-PD1 antibody significantly prolonged survival in this model. Comparing to the combination of FAKi and anti-PD1 antibody, adding PEGPH20 significantly decreased the number of CXCR4-expressing myeloid cells in the tumor microenvironment (TME) of PDAC and consequently led to an increase in the amount of CCR7+ central memory T cells. Additionally, the amount of G-MDSCs, inflammatory resident monocytes and PDL1 expressing myeloid cells in the TME of PDAC, was also decreased in PDAC treated with the triple combination of PEGPH20, FAKi and anti-PD1 antibody compared to FAKi and anti-PD1 antibody.ConclusionFAK is widely expressed in myeloid cell populations, directly correlated with CXCR4 expression and decreased FAK expression in a myeloid (M2 TAMs, neutrophil) inflamed stroma is associated with infiltration of effector CD8 T cells in human PDAC. Stromal degradation of hyaluronan via PEGPH20 combined with FAKi and anti-PD1 antibody further depletes immunosuppressive cells in the TME including G-MDSCs, inflammatory resident monocytes and PDL1 expressing myeloid cells and appears to target the CXCR4 pathway through PEGPH20. These findings support testing the combination of FAKi and anti-PD1 antibody with agents targeting CXCR4 directly or indirectly by PEGPH20 in human PDAC.Disclosure InformationA. Osipov: None. L. Zheng: None.

scholarly journals 49 In situ phenotypic analysis of T cells in the tumor microenvironment of a pre-clinical model of non-small cell lung cancer (NSCLC) by tissue sectioning and whole-mount immunofluorescence imaging

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A52-A52
Author(s):  
Elen Torres ◽  
Stefani Spranger
Keyword(s):  
T Cells ◽  
Spatial Distribution ◽  
T Cell ◽  
Spatial Location ◽  
Cell Infiltration ◽  
Cell Populations ◽  
Tumor Bearing ◽  
T Cell Infiltration ◽  
Volume Imaging ◽  
Whole Mount

BackgroundUnderstanding the interactions between tumor and immune cells is critical for improving current immunotherapies. Pre-clinical and clinical evidence has shown that failed T cell infiltration into lung cancer lesions might be associated with low responsiveness towards checkpoint blockade.1 For this reason, it is necessary to characterize not only the phenotype of T cells in tumor-bearing lungs but also their spatial location in the tumor microenvironment (TME). Multiplex immunofluorescence staining allows the simultaneous use of several cell markers to study the state and the spatial location of cell populations in the tissue of interest. Although this technique is usually applied to thin tissue sections (5 to 12 µm), the analysis of large tissue volumes may provide a better understanding of the spatial distribution of cells in relation to the TME. Here, we analyzed the number and spatial distribution of cytotoxic T cells and other immune cells in the TME of tumor-bearing lungs, using both 12 µm sections and whole-mount preparations imaged by confocal microscopy.MethodsLung tumors were induced in C57BL/6 mice by tail vein injection of a cancer cell line derived from KrasG12D/+ and Tp53-/- mice. Lung tissue with a diverse degree of T cell infiltration was collected after 21 days post tumor induction. Tissue was fixed in 4% PFA, followed by snap-frozen for sectioning. Whole-mount preparations were processed according to Weizhe Li et al. (2019) 2 for tissue clearing and multiplex volume imaging. T cells were labeled with CD8 and FOXP3 antibodies to identify cytotoxic or regulatory T cells, respectively. Tumor cells were labeled with a pan-Keratin antibody. Images were acquired using a Leica SP8 confocal microscope. FIJI3 and IMARIS were used for image processing.ResultsWe identified both cytotoxic and regulatory T cell populations in the TME using thin sections and whole-mount. However, using whole-mount after tissue clearing allowed us to better evaluate the spatial distribution of the T cell populations in relation to the tumor structure. Furthermore, tissue clearance facilitates the imaging of larger volumes using multiplex immunofluorescence.ConclusionsAnalysis of large lung tissue volumes provides a better understanding of the location of immune cell populations in relation to the TME and allows to study heterogeneous immune infiltration on a per-lesion base. This valuable information will improve the characterization of the TME and the definition of cancer-immune phenotypes in NSCLC.ReferencesTeng MW, et al., Classifying cancers based on T-cell infiltration and PD-L1. Cancer Res 2015;75(11): p. 2139–45.Li W, Germain RN, and Gerner MY. High-dimensional cell-level analysis of tissues with Ce3D multiplex volume imaging. Nat Protoc 2019;14(6): p. 1708–1733.Schindelin J, et al, Fiji: an open-source platform for biological-image analysis. Nat Methods 2012;9(7): p. 676–82.

scholarly journals Targeted deletion of PD-1 in myeloid cells induces antitumor immunity

2020 ◽  
Vol 5 (43) ◽  
pp. eaay1863 ◽  
Author(s):  
Laura Strauss ◽  
Mohamed A. A. Mahmoud ◽  
Jessica D. Weaver ◽  
Natalia M. Tijaro-Ovalle ◽  
Anthos Christofides ◽  
...  
Keyword(s):  
T Cell ◽  
Antitumor Immunity ◽  
Myeloid Cells ◽  
Suppressor Cells ◽  
Myeloid Cell ◽  
Tca Cycle ◽  
Pentose Phosphate ◽  
Metabolic Reprogramming ◽  
Effector Memory ◽  
Emergency Myelopoiesis

PD-1, a T cell checkpoint receptor and target of cancer immunotherapy, is also expressed on myeloid cells. The role of myeloid-specific versus T cell–specific PD-1 ablation on antitumor immunity has remained unclear because most studies have used either PD-1–blocking antibodies or complete PD-1 KO mice. We generated a conditional allele, which allowed myeloid-specific (PD-1f/fLysMcre) or T cell–specific (PD-1f/fCD4cre) targeting of Pdcd1 gene. Compared with T cell–specific PD-1 ablation, myeloid cell–specific PD-1 ablation more effectively decreased tumor growth. We found that granulocyte/macrophage progenitors (GMPs), which accumulate during cancer-driven emergency myelopoiesis and give rise to myeloid-derived suppressor cells (MDSCs), express PD-1. In tumor-bearing PD-1f/fLysMcre but not PD-1f/fCD4cre mice, accumulation of GMP and MDSC was prevented, whereas systemic output of effector myeloid cells was increased. Myeloid cell–specific PD-1 ablation induced an increase of T effector memory cells with improved functionality and mediated antitumor protection despite preserved PD-1 expression in T cells. In PD-1–deficient myeloid progenitors, growth factors driving emergency myelopoiesis induced increased metabolic intermediates of glycolysis, pentose phosphate pathway, and TCA cycle but, most prominently, elevated cholesterol. Because cholesterol is required for differentiation of inflammatory macrophages and DC and promotes antigen-presenting function, our findings indicate that metabolic reprogramming of emergency myelopoiesis and differentiation of effector myeloid cells might be a key mechanism of antitumor immunity mediated by PD-1 blockade.

scholarly journals P08.02 CCR2/CCR5 dual-antagonist ‘licenses’ the radiation-induced effector T-cell infiltration in the anti-PD-1 antibody-treated pancreatic adenocarcinoma

2021 ◽  
Vol 9 (Suppl 1) ◽  
pp. A25.1-A25
Author(s):  
J Wang ◽  
M Tun Saung ◽  
K Fujiwara ◽  
N Niu ◽  
A Narang ◽  
...  
Keyword(s):  
T Cell ◽  
Rna Sequencing ◽  
Checkpoint Inhibitors ◽  
Cell Infiltration ◽  
Ductal Adenocarcinoma ◽  
Pancreatic Tumors ◽  
Prolonged Treatment ◽  
Effector T Cell ◽  
T Cell Infiltration ◽  
T Cell Priming

BackgroundThe resistance of pancreatic ductal adenocarcinoma(PDAC) to immune checkpoint inhibitors(ICIs) is mainly attributed to the immune-quiescent nature of its tumor microenvironment(TME). Radiotherapy(RT) activates innate responses including the RAGE and TLR2/4 pathways and subsequently modifies the TME by promoting the release of chemokines that recruit inflammatory cells into the TME. In this preclinical study, we examined the PDAC vaccine or RT as a T-cell priming mechanism together with BMS-687681, a small molecule dual-antagonist of CCR2 and CCR5(CCR2/5i) as an immunosuppressive TME-targeting agent, in combination with the anti-PD-1 antibody(αPD-1) as a new treatment.Materials and MethodsThe hemi-spleen and Orthotopic mice model were used to investigate both GVAX and RT as T-cell priming agents in combination regimens that included αPD-1 and CCR2/5i. Dissected orthotopic pancreatic tumors were collected for analysis of tumor-infiltrating immune cells by flow cytometry. RNA from tumor-infiltrating immune cell pellets and whole-exome RNA sequencing was performed for further mechanism research.ResultsCCR2 and CCR5 are associated with the immunosuppressive TME of PDAC patients and their expression were induced after treatment with GVAX+nivolumab. Using a mouse model of PDAC, we demonstrated that the addition of GVAX to CCR2/5i+αPD-1 combination therapy did not significantly improve antitumor activity. However, RT followed by αPD-1 and prolonged treatment with CCR2/5i conferred significantly better antitumor efficacy compared to the other combination treatments we studied. The combination of RT, αPD-1, and CCR2/5i enhanced intratumoral effector and memory T-cell infiltration. This combination suppressed Treg, M2-like TAM, and M-MDSC infiltration, but not M1-like TAM and PMN-MDSC infiltration. Finally, RNA sequencing showed that CCR2/5i partially inhibited RT-induced TLR2/4&RAGE signaling, which would have otherwise led to the release of immunosuppressive cytokines including CCL2 and CCL5. The inhibition of TLR2/4&RAGE signaling permitted the expression of effector T-cell chemokines such as CCL17 and CCL22.ConclusionsThis study thus supports the clinical development of CCR2/5i in combination with RT and ICIs for PDAC treatment.Disclosure InformationJ. Wang: None. M. Tun Saung: None. K. Fujiwara: None. N. Niu: None. A. Narang: None. J. He: None. L. Zheng: None.

scholarly journals Male Bovine GH Transgenic Mice Have Decreased Adiposity With an Adipose Depot-Specific Increase in Immune Cell Populations

Endocrinology ◽  
2014 ◽  
Vol 156 (5) ◽  
pp. 1794-1803 ◽  
Author(s):  
Fabian Benencia ◽  
Stephanie Harshman ◽  
Silvana Duran-Ortiz ◽  
Ellen R. Lubbers ◽  
Edward O. List ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Cell ◽  
Stromal Vascular Fraction ◽  
Cell Infiltration ◽  
Cell Populations ◽  
Adipose Depot ◽  
T Cell Infiltration ◽  
Specific Manner ◽  
In Vivo Effects

White adipose tissue (WAT) is composed of mature adipocytes and a stromal vascular fraction (SVF), which contains a variety of cells, including immune cells that vary among the different WAT depots. Growth hormone (GH) impacts immune function and adiposity in an adipose depot-specific manner. However, its effects on WAT immune cell populations remain unstudied. Bovine GH transgenic (bGH) mice are commonly used to study the in vivo effects of GH. These giant mice have an excess of GH action, impaired glucose metabolism, decreased adiposity, increased lean mass, and a shortened lifespan. Therefore, the purpose of this study was to characterize the WAT depot-specific differences in immune cell populations in the presence of excess GH in vivo. Three WAT depots were assessed: inguinal (sc), epididymal (EPI), and mesenteric (MES). Subcutaneous and MES bGH WAT depots showed a significantly higher number of total SVF cells, yet only MES bGH WAT had higher leukocyte counts compared with control samples. By means of flow cytometry analysis of the SVF, we detected greater macrophage and regulatory T-cell infiltration in sc and MES bGH WAT depots compared with controls. However, no differences were observed in the EPI WAT depot. RNA-sequencing confirmed significant alterations in pathways related to T-cell infiltration and activation in the sc depot with fewer significant changes in the EPI bGH WAT depot. These findings collectively point to a previously unrecognized role for GH in influencing the distribution of WAT immune cell populations in a depot-specific manner.

scholarly journals Microglia and Perivascular Macrophages Act as Antigen Presenting Cells to Promote CD8 T Cell Infiltration of the Brain

2021 ◽  
Vol 12 ◽  
Author(s):  
Emma N. Goddery ◽  
Cori E. Fain ◽  
Chloe G. Lipovsky ◽  
Katayoun Ayasoufi ◽  
Lila T. Yokanovich ◽  
...  
Keyword(s):  
T Cell ◽  
Mhc Class I ◽  
Myeloid Cells ◽  
Antigen Presenting Cells ◽  
Cd8 T Cell ◽  
Class I ◽  
Cell Infiltration ◽  
Host Protection ◽  
T Cell Infiltration ◽  
Antigen Presenting

CD8 T cell infiltration of the central nervous system (CNS) is necessary for host protection but contributes to neuropathology. Antigen presenting cells (APCs) situated at CNS borders are thought to mediate T cell entry into the parenchyma during neuroinflammation. The identity of the CNS-resident APC that presents antigen via major histocompatibility complex (MHC) class I to CD8 T cells is unknown. Herein, we characterize MHC class I expression in the naïve and virally infected brain and identify microglia and macrophages (CNS-myeloid cells) as APCs that upregulate H-2Kb and H-2Db upon infection. Conditional ablation of H-2Kb and H-2Db from CNS-myeloid cells allowed us to determine that antigen presentation via H-2Db, but not H-2Kb, was required for CNS immune infiltration during Theiler’s murine encephalomyelitis virus (TMEV) infection and drives brain atrophy as a consequence of infection. These results demonstrate that CNS-myeloid cells are key APCs mediating CD8 T cell brain infiltration.

scholarly journals Differences in maintenance of CD8+ and CD4+ bacteria-specific effector-memory T cell populations

2003 ◽  
Vol 33 (10) ◽  
pp. 2875-2885 ◽  
Author(s):  
Matthias Schiemann ◽  
Verena Busch ◽  
Kathrin Linkemann ◽  
Katharina M. Huster ◽  
Dirk H. Busch
Keyword(s):  
T Cell ◽  
Effector Memory ◽  
Cell Populations ◽  
Memory T Cell ◽  
Specific Effector

scholarly journals Modulating tumor infiltrating myeloid cells to enhance bispecific antibody-driven T cell infiltration and anti-tumor response

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Jeong A. Park ◽  
Linlin Wang ◽  
Nai-Kong V. Cheung
Keyword(s):  
T Cells ◽  
T Cell ◽  
Bispecific Antibody ◽  
Tumor Response ◽  
Human Cancer ◽  
Myeloid Cells ◽  
Human Tumor ◽  
Cell Infiltration ◽  
Tumor Control ◽  
T Cell Infiltration

Abstract Background Tumor microenvironment (TME) is a dynamic cellular milieu to promote tumor angiogenesis, growth, proliferation, and metastasis, while derailing the host anti-tumor response. TME impedes bispecific antibody (BsAb) or chimeric antigen receptor (CAR)-driven T cells infiltration, survival, and cytotoxic efficacy. Modulating tumor infiltrating myeloid cells (TIMs) could potentially improve the efficacy of BsAb. Methods We evaluated the effects of TIM modulation on BsAb-driven T cell infiltration into tumors, their persistence, and in vivo anti-tumor response. Anti-GD2 BsAb and anti-HER2 BsAb built on IgG-[L]-scFv platform were tested against human cancer xenografts in BALB-Rag2−/−IL-2R-γc-KO (BRG) mice. Depleting antibodies specific for polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC), monocytic MDSC (M-MDSC), and tumor associated macrophage (TAM) were used to study the role of each TIM component. Dexamethasone, an established anti-inflammatory agent, was tested for its effect on TIMs. Results BsAb-driven T cells recruited myeloid cells into human tumor xenografts. Each TIM targeting therapy depleted cells of interest in blood and in tumors. Depletion of PMN-MDSCs, M-MDSCs, and particularly TAMs was associated with enhanced T cell infiltration into tumors, significantly improving tumor control and survival in multiple cancer xenograft models. Dexamethasone premedication depleted monocytes in circulation and TAMs in tumors, enhanced BsAb-driven T cell infiltration, and anti-tumor response with survival benefit. Conclusion Reducing TIMs markedly enhanced anti-tumor effects of BsAb-based T cell immunotherapy by improving intratumoral T cell infiltration and persistence. TAM depletion was more effective than PMN- or M-MDSCs depletion at boosting the anti-tumor response of T cell engaging BsAb.

scholarly journals TP53 missense mutations in PDAC are associated with enhanced fibrosis and an immunosuppressive microenvironment

2021 ◽  
Vol 118 (23) ◽  
pp. e2025631118
Author(s):  
Martino Maddalena ◽  
Giuseppe Mallel ◽  
Nishanth Belugali Nataraj ◽  
Michal Shreberk-Shaked ◽  
Ori Hassin ◽  
...  
Keyword(s):  
T Cell ◽  
Cancer Cells ◽  
Suppressor Gene ◽  
The Cancer Genome Atlas ◽  
Cell Infiltration ◽  
Ductal Adenocarcinoma ◽  
Missense Mutations ◽  
T Cell Infiltration ◽  
Dismal Prognosis ◽  
Immunosuppressive Microenvironment

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer, which is refractory to all currently available treatments and bears dismal prognosis. About 70% of all PDAC cases harbor mutations in the TP53 tumor suppressor gene. Many of those are missense mutations, resulting in abundant production of mutant p53 (mutp53) protein in the cancer cells. Analysis of human PDAC patient data from The Cancer Genome Atlas (TCGA) revealed a negative association between the presence of missense mutp53 and infiltration of CD8+ T cells into the tumor. Moreover, CD8+ T cell infiltration was negatively correlated with the expression of fibrosis-associated genes. Importantly, silencing of endogenous mutp53 in KPC cells, derived from mouse PDAC tumors driven by mutant Kras and mutp53, down-regulated fibrosis and elevated CD8+ T cell infiltration in the tumors arising upon orthotopic injection of these cells into the pancreas of syngeneic mice. Moreover, the tumors generated by mutp53-silenced KPC cells were markedly smaller than those elicited by mutp53-proficient control KPC cells. Altogether, our findings suggest that missense p53 mutations may contribute to worse PDAC prognosis by promoting a more vigorous fibrotic tumor microenvironment and impeding the ability of the immune system to eliminate the cancer cells.

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