bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel, synthetic TLR7/8 agonist demonstrates monotherapy efficacy and synergy with anti-PD-1 in syngeneic mouse tumor models
Authors: Beyer Caleb A , Lussier Danielle , Jackson Konner , Whitacre Margaret , Ward Janine , Schoener Roman , Bazin Helene G , Burkhart David , Miller Shannon M 
Published: January 2023

Abstract
Cancer is the second leading cause of death in the United States, with more than half a million Americans succumbing to this disease every year. To date, immunotherapies such as anti-PD-1 and anti-CTLA-4 have shown some advancement toward treating certain cancer types, but efficacy is typically reserved for a small subset of cancer patients. Recent clinical trials have shown that melanoma and renal cell carcinoma patients had some of the highest rates of response to checkpoint treatment, but even then, the rate of response was only 20% and 22%, respectively. Furthermore, immunotherapies can lead to severe adverse reactions due to their ability to activate non-specific immune responses. Inimmune has developed and tested a novel TLR7/8 agonist as an immunotherapy for cancer. In vivo mouse studies demonstrated that IV treatment with our novel, synthetic TLR7/8 agonist in combination with anti-PD-1 resulted in increased efficacy in eliminating tumors or slowing tumor growth over anti-PD-1 treatment alone in B16F10 and MC38 tumor models in C57BL/6 mice. Furthermore, lead formulations of our novel, synthetic TLR7/8 agonist demonstrated efficacy as a monotherapy in BALB/c mice inoculated with a highly tumorigenic Lewis Lung Carcinoma (LLC) cell line. Taken together, our data indicate that this novel, synthetic TLR7/8 agonist was tolerated systemically, functioned as a monotherapy, and synergized well with anti-PD-1 treatment in various mouse syngeneic tumor models. As we move this compound to Phase 1 clinical trials, these data suggest that our TLR7/8 agonist can be dosed safely as a monotherapy or in combination with checkpoint therapy and may drive efficacious anti-tumor responses in humans.
Complement downregulation promotes an inflammatory signature that renders colorectal cancer susceptible to immunotherapy
Authors: Guglietta Silvia , Weber Lukas M , Fosso Bruno , Hardiman Gary , Olcina Monica M , Marzano Marinella , Robinson Mark D , Krieg Carsten 
Published: January 2023

Abstract
The role of inflammation in colorectal cancer (CRC) development and response to therapy is highly debated. While inflammation is a known driver of CRC, inflammatory immune infiltrates are a positive prognostic factor in CRC as inflammation can enhance response to immune checkpoint blockade (ICB) therapy. Yet, the majority of CRC are poorly infiltrated and even in presence of an inflammatory infiltrate half of these cancers become refractory to ICB. Therefore, there is a need to identify mechanisms to establish therapy supportive inflammation. We have previously reported that certain patients with CRC down-regulate the receptor for the complement anaphylatoxin C3a (C3aR). The complement system is a first line of defense against pathogens and a central component of the immune response. Emerging evidence suggests that C3aR may play a role in intestinal homeostasis. However, to date, it is unknown how C3aR affects CRC development and response to therapy with ICB.
Using our novel mouse model of CRC (APCMin/+/C3aR−/−) we showed that loss of C3aR results in enhanced immune infiltration in typically “cold” tumors and changes in the intestinal microbiota. Similarly, we found that down-regulation of the complement C3aR in patients correlates with changes in specific tumor-infiltrating immune cells. Notably, when treated with a-PD1, APCMin/+/C3aR−/− mice showed a significant reduction of tumors, suggesting that the loss of C3aR unleashes in the colon a microbiota-mediated immune response that can be exploited for therapeutic purposes.
Our findings reveal that C3aR may act as a previously unrecognized checkpoint to enhance antitumor immunity in CRC and that C3aR inhibition may be used to overcome ICB resistance in a larger group of CRC patients.
This project was supported in part by NIH P20 GM120475 (core facility) at the MUSC Digestive Disease Research Core Center.
CD28: A roadblock to designing long-lasting CARs?
Authors: Honikel Mackenzie M , Holling G Aaron , Burchett Rebecca , Bramson Jonathan , Lee Kelvin P , Olejniczak Scott H 
Published: January 2023

Abstract
Multiple myeloma (MM) remains an incurable hematological malignancy by conventional chemotherapeutic approaches. Chimeric antigen receptor T (CAR-T) cells targeting B cell maturation antigen (BCMA) on MM have shown remarkable efficacy in relapsed/refractory patients, leading to their recent FDA approval. However, many MM patients fail to achieve durable remissions leading to relapse in the months following treatment, highlighting the need to better understand mechanisms of CAR-T cell failure. Recent studies demonstrate that reducing CD28 co-stimulatory signals delivered by CARs promote CAR-T cell persistence and reduce exhaustion. Whether endogenous CD28 co-stimulation contributes to in vivo CAR-T cell transience or dysfunction is unknown. Our preliminary data indicate that genetic deletion of the endogenous CD28 receptor does not impair CAR-T cell cytotoxicity but promotes in vivo persistence while targeted mutation of CD28 reduces exhaustion marker expression. These findings suggest that targeting endogenous CD28 on CAR-T cells with CTLA4-Ig (Abatacept) may represent a viable clinical strategy to increase the durability of a potent CAR-T cell design. Importantly, in the context of MM, we have previously shown that CD28 is expressed on and delivers pro-survival signals to MM, contributing to therapy resistance. Moreover, given the abundance of CD28 ligands, CD80 and CD86, within the bone marrow, we hypothesize that CD28 signaling reduces the efficacy of BCMA CAR-T therapy by providing a survival signal to MM cells while simultaneously limiting the durability of CAR-T cells. The combination therapy of BCMA CAR-T cells and Abatacept is expected to enhance the efficacy of adoptive CAR-T cell therapy for MM patients.
This work is supported by grants from NIH (R03 CA256122, R01 AI155499).
Fluorescence tagging to monitor CD8 T cell recirculation from the tumor to the tumor-draining lymph node: the impact of focal radiation therapy on recirculation
Authors: Gough Michael J , Blair Tiffany , Dowdell Alexa K , Bambina Shelly , Kramer Gwen , Piening Brian D , Crittenden Marka R 
Published: January 2023

Abstract
T cells are continuously moving through tissues and recirculating back into the peripheral blood via lymph nodes. In cancer, tumor-specific T cells are enriched in the tumor environment and their presence is associated with improved outcome in patients and in preclinical models. T cells are known to contribute to tumor control following radiotherapy despite evidence indicating that radiation can be directly cytotoxic to lymphocytes. The impact of radiation therapy on recirculation of T cells through the tumor to the tumor draining lymph node (TDLN) and their trafficking to distant sites is unclear. By photoconverting tumor infiltrating cells using focal UV in Kaede mice we can use fluorescence tagging to directly identify T cells in the TDLN that originated in the tumor. We demonstrate that radiation therapy significantly decreases CD8 T cell trafficking from the tumor to the TDLN. Using single cell RNASeq and flow cytometry, we demonstrate that radiation therapy is locally cytotoxic to proliferating effector CD8 T cells within the tumor environment. This results in the loss of this effector population in the TDLN following treatment. Using flow cytometry and direct blockade of T cell entry into the LN, we characterize the CD8 T cells in the TDLN that proliferate following radiation therapy. Our data demonstrate that radiation therapy is locally cytotoxic and restricts CD8 T cell recirculation to the TDLN. Since tumor control following radiation therapy is partially dependent on CD8 T cell responses, these data force us to re-evaluate both the type and location of T cell populations that contribute to tumor control following radiation therapy.
Supported by grants from the NIH (R01CA182311, R01CA244142, R01CA208644)
Induction of Inflammatory Macrophages in Solid Tumors by All-trans Retinoic Acid Augments Radiation Efficacy
Authors: Liang Hua Laura , Rao Enyu , Hou Yuzhu , Wang Jiaai , Huang Xiaona , Yu Xianbin , Wang Liangliang , He Chuan , Vokes Everett , Weichselbaum Ralph 
Published: January 2023

Abstract
Radiotherapy is an important anticancer treatment modality that activates innate and adaptive immune responses. Local RT induces an influx of myeloid cells (mostly myeloid-derived suppressor cells MDSCs), which suppress T-cell function, in the tumor microenvironment (TME). Alleviating therapy-induced immunosuppression would address a significant barrier to the efficacy of current cancer immunotherapeutic approaches. When all-trans retinoic acid (RA) was administered with radiation, we observed superior antitumor responses compared with ionizing radiation (IR) alone or RA alone. The effects of combination treatment were accompanied by a marked increase of tumor necrosis factor–α– (TNFα) and inducible nitric oxide synthase (iNOS)–producing inflammatory macrophages in local and distal nonirradiated tumors. Inflammatory macrophages (Inf-MAC) are essential for the therapeutic efficacy of combination treatment by inducing effector T cell infiltration and enhancing the effector T cell to regulatory T cell ratio in local and distal tumors. T cells and T cell–derived interferon-γ are crucial for increasing inflammatory macrophage levels in IR- and RA-treated tumors. The synergistic positive feedback loop of inflammatory macrophages and adaptive immunity is required for the antitumor efficacy of IR + RA combination treatment. Our findings provide a translational and relatively nontoxic strategy for enhancing the local and systemic antitumor effects of IR. Single cell RNAseq of immune infiltrates revealed unique transcriptional changes delineating the differentiation of Inf-Mac in the TME which may lead to potential specific therapeutic targets.
Preoperative exercise therapy attenuates liver metastases following surgical stress by inducing Kupffer cells-mediated anti-tumor immunity
Authors: Zhang Hongji , Cheng Xiang , Deng Meihong , Tsung Allan , Huang Hai 
Published: January 2023

Abstract

Introduction
Resection of colorectal cancer hepatic metastases improves overall disease-free survival. Unfortunately, not all patients have a successful surgical outcome. Pre-operative exercise therapy (PEx) have been demonstrated to be beneficial in the prevention of post-operative complications. We hypothesize that PEx initially reverts pro-tumorigenic inflammatory responses following surgical stress and maintains an anti-tumor immune microenvironment through modulating Kupffer cells (KCs) with anti-tumor immunity.

Methods
8W C57BL/6 mice were randomly divided into PEx and sedentary (Sed) groups, mice with PEx run on a motorized treadmill at a speed of 12.5 m/min for 60 min/day, 5 days/W for 4 weeks. 105 MC38 cells were injected directly through portal vein and surgical stress was subjected to partial hepatic ischemia and reperfusion model. Both hepatic and tumor CD45+ cells from PEx or Sed mice 3 W after IR were submitted for single-cell RNA sequencing (scRNA-seq).

Results
4 weeks of PEx significantly reduces metastasis in the liver along 3 weeks after IR, compared with Sed controls. For the scRNA-seq, 11 cell lineages were identified and annotated according to the transcriptomic profile of feature genes expression. Surprisingly, discontinued 4-week-PEx still led to a significant transcriptomic shift in the KCs. 3 clusters from the entire KCs population were unique in PEx mice. In contrast, 2 Clusters were derived from Sed mice. PEx-relevant KCs are enriched in gene expression related to the anti-tumor phenotype, whereas Sed-relevant KCs are enriched in gene expression related to pro-tumor or immunosuppressive phenotype, which suggests that PEx modulates transcriptomic changes in KCs towards an anti-tumor phenotype.
Supported by National Institutes of Health R01-CA214865-01 and R01-GM95566-06 to AT, National Institutes of Health R01-AI152044 to MD, and National Institutes of Health R01-GM137203 and Joseph A. Patrick Research Fellowship in Transplantation to HH.
β-adrenergic signaling modulates the development and activity of erythroid suppressor cells
Authors: Chawla Arshmeet K , Nevin James , Moussa Marmar , Geyer Rory , Mandoiu Ion , Srivastava Pramod K 
Published: January 2023

Abstract
The neuroimmune response to stress has been linked to enhanced tumor proliferation, angiogenesis, and metastasis. In particular, signaling through β-adrenergic receptors has been demonstrated to promote a highly immunosuppressive tumor microenvironment by favoring the development and recruitment of suppressive immune cells, including regulatory T cells and myeloid-derived suppressive cells, that inhibit the cytotoxic CD8+ T cell response and enhance tumor progression. Interestingly, the complexity and scope of cancer immunosuppression extends beyond classical immune cells. Immunosuppressive erythroid progenitors, deemed erythroid suppressor cells (ESCs), have been shown to be prominent players in suppressing CD8+ T cell-mediated tumor responses; however, little is known about how these cells develop and are regulated. Thus, we examined if β-adrenergic signaling affects the development of ESCs and their role in tumor immunity. In this study, we show that β-adrenergic signaling promotes the accumulation of CD71+ Ter119+ erythroid progenitors consistent with the phenotypic description of ESCs in tumor-bearing mice. In characterizing the phenotype of these cells by flow cytometry and single-cell RNA sequencing, we elucidate unique features that endow these cells with immunosuppressive activity and illustrate their sensitivity to regulation by the sympathetic nervous system. We further demonstrate these erythroid precursors exhibit suppressive effects on the CD8 response. These findings elucidate a previously unappreciated axis of neuroimmune coordination in cancer and are pivotal to understanding crucial elements of tumor progression that will help shape the course of targeted immunotherapies in the future.
TNF-α blockade improves immunotherapy efficacy by altering the tumor microenvironment and enhancing tumor-specific T cell function in pancreatic ductal adenocarcinoma
Authors: Burrack Adam L , Schmiechen Zoe , Miller Ebony , Stromnes Ingunn 
Published: January 2023

Abstract
Pancreatic ductal adenocarcinoma (PDA) is a particularly lethal malignancy with a 5-year survival rate of 9%. A recent phase 1 clinical trial suggests CD40 agonist has antitumor activity in some patients. We developed an orthotopic PDA mouse model to track tumor specific CD8 T cells, identify critical antitumor mechanisms, and determine pathways of immunotherapy resistance. Here, we exploit this model to uncover a novel combination immunotherapy that includes CD40 agonist, PD-L1 blockade and TNF-α neutralization (e.g., 4PT). Interfering with TNF-α significantly improves overall mouse survival and cure rate compared to CD40+PDL1 only (4P). Critically, 4PT enhanced the generation of tumor-specific long-lived effector and central memory T cells. TNF-α neutralization significantly reduced T cell exhaustion, as indicated by reduced Lag-3 and increased IFN-γ production by intratumoral tetramer+ CD8 T cells. Additionally, 4PT increased CD4+Foxp3− T cell frequency and decreased CD4+Foxp3+ T cells as compared to 4P-treated mice, consistent with enhanced antitumor CD4 T cell reactivity in the absence of chronic TNF-α signaling. Lastly, abrogating Tnfr1 significantly reduced splenic and intratumoral Ly6G+ granulocytes following 4P. Thus, disrupting TNF-α via genetic deletion or monoclonal antibodies alters the tumor microenvironment to promote highly functional tumor-specific CD8 T cells. We conclude that perturbation of TNF-α-mediated chronic inflammation is an appealing approach to enhance immunotherapy efficacy for pancreatic cancer patient treatment.
Supported by NIH 1R01CA249393-01A1
Resistance to Anti-PD-1 Therapy is mediated via the Microbiota-Th17-Prostoglandin E2 Axis in the LSLKrasG12D Lung Cancer Model
Authors: Li Qingsheng , Goggin Kevin Edward , Seo Jamie , Egilmez Nejat 
Published: January 2023

Abstract
We previously demonstrated that anti-PD-1 antibody mediated activation of type 17 T-cells undermined checkpoint inhibitor therapy in the LSLKrasG12D murine lung cancer model. In this study we confirm that the Th17 subset is the primary driver of resistance to anti-PD-1; demonstrate that the ontogeny of dysplasia-associated Th17 cells is driven by microbiota-conditioned macrophages; and identify IL-17-COX-2/Prostoglandin E2 (PGE2) axis as the mediator of CD8+ cytotoxic T-lymphocyte (CTL) de-sensitization to checkpoint inhibitor therapy. Specifically, anti-PD-1 treatment of CD4+ T-cell RORc-deficient LSLKrasG12D mice resulted in a 50% increase in CTL cytotoxicity and a 2.2-fold reduction in tumor burden confirming the critical role of Th17 cells in resistance to therapy. Lung-specific depletion of microbiota reduced Th17 cell prevalence and tumor burden by ~2 and ~1.5 fold, respectively, establishing a link between microbiota and the Th17-driven tumorigenesis. Importantly, interstitial macrophages from microbiota sufficient, but not from microbiota-deficient, mice polarized naïve CD4+ T-cells towards a Th17 phenotype, highlighting their role in bridging microbiota and lung Th17 immunity. Neutralization of IL-17 diminished COX-2/PGE2 levels, whereas inhibition of COX-2 rescued CTL activity and restored tumor suppression in anti-PD-1 antibody-treated mice, revealing the molecular basis of IL-17-driven anti-PD-1 resistance. The clinical implications of these findings are discussed.
Supported by grant from DOD grant (to N.E., OGMB190737) and in part through the NIH/NIGMS P20-GM135004 (1P20GM135005-01)
NASAL NANO-VACCINE PREVENTS PRIMARY BREAST TUMOR FROM MAKING THE LUNG ITS NEW HOME
Authors: Donkor Michael Ahenkora , Jones Harlan 
Published: January 2023

Abstract
Despite medical advances in the diagnosis and treatment of cancer, metastatic breast cancers remain a leading cause of death in the U.S. Increasingly, novel immune-based treatments which harness the patient’s immune system have promise for improving survivorship. Such therapies take advantage of the immune system’s natural defense mechanisms to halt progression of breast cancer. This is through the early activation of innate immune cells such as natural killer cells and the subsequent activation of the adaptive immune responses such as T and B lymphocytes. Researchers have taken advantage of these immune mechanisms of tumor defense as a complementary approach to current radio-chemo treatments, which have shown to be limited by adverse off-target effects on patients. Ongoing research in our laboratory is focused on using nanotechnology to develop immune-based vaccines to target local immune protection against metastatic lung disease. Because the lung is naturally tolerogenic, making it easy for disseminated tumor cells to grow, the expectation is that boosting immune responses at the lungs before seeding tumors from primary organs would mitigate metastasis and reduce mortality risks. Using an experimental murine breast cancer model of metastasis, we examined the effect of intranasal vaccination to induce local and systemic adaptive immune responses. We hypothesized that an intranasal vaccine protocol would increase antigen-specific adaptive responses across the respiratory tract. Our results demonstrated that intranasal vaccination provides protection against secondary lung metastasis due to increased accumulation functional CD4+ and CD8+ T cells in the lungs as shown by flow cytometry and ELISA techniques.
Supported by National Institute of Cancer Research of the Health under Award 1 P20 CA233355-01
P2RX7 enhances tumor control by CD8+ T cells in adoptive cell therapy
Authors: Wanhainen Kelsey , Peng Changwei , O’flanagan Stephen , Burbach Brandon , da Silva Henrique Borges , Jameson Stephen 
Published: January 2023

Abstract
Expression of the purinergic receptor P2RX7 by CD8+ T cells promotes generation of memory populations following acute infections and is critical for responses to chronic infection. Despite these findings, recent studies have indicated that P2RX7 may limit the efficacy of anti-tumor responses. We show that P2RX7 is beneficial for optimal melanoma control in a mouse CD8+ T cell adoptive transfer model. Tumor specific P2rx7−/− CD8+ T cells exhibited impaired mitochondrial maintenance and function, but do not display signs of overt exhaustion or poor survival early in the anti-tumor response. However, as tumor burden increases the frequency P2RX7 deficient CD8+ T cells progressively declines relative to WT CD8+ T cells within the tumor. This was associated with worsening mitochondrial function and increased expression of some markers of T cell exhaustion among P2rx7−/− CD8+ T cells. Extending these studies, we found that transient in vitro stimulation of P2RX7 using the ATP analog BzATP led to enhanced B16 tumor control by CD8+ T cells. The improved ability of BzATP stimulated CD8+ T cells to prolong survival of tumor bearing mice was accompanied by enhanced mitochondrial function of tumor specific CD8+ T cells. These findings are in keeping with the concept that extracellular ATP (eATP) sensing by P2RX7 on CD8+ T cells is required for their ability to efficiently eliminate tumors by promoting mitochondrial fitness and indicates the potential for P2RX7 stimulation as a novel therapeutic treatment to enhance tumor immunotherapy.
Supported by grants F30 award from the NIH (1F30CA250321-01)
Tumor-induced, TCR-independent upregulation of A2AR expression in effector CD8+ T cells
Authors: Zhou Maggie , da Silva Henrique Borges 
Published: January 2023

Abstract
The tumor microenvironment (TME) is characterized by high levels of extracellular ATP (eATP) and adenosine, which are sensed by purinergic receptors. CD8+ T cells express two important receptors that bind these ligands: the extracellular receptor P2RX7 binds eATP and is generally immunostimulatory, while the adenosine receptor A2AR promotes immunosuppression. However, the role of the TME itself in the T cell expression of purinergic receptors is not clear. We used in vitro co-cultures of tumor cells and CD8+ T cells, and specifically found that A2AR is significantly upregulated after activation, in a tumor cell number-correlated manner. These tumor-induced changes in A2AR expression are independent of TCR:MHC contact, which was evidenced by co-cultures using transwells to physically separate tumor cells and T cells, as well as distinct combination of transgenic T cells and tumors. In vivo murine solid tumor models confirmed that tumor-infiltrating CD8+ T cells upregulate A2AR. As previously found by our group, P2RX7 expression is limited to a small percentage of tumor-infiltrating CD8+ T cells. Interestingly, we identified that these few P2RX7-expressing tumor-infiltrating CD8+ T cells are enriched for high A2AR expression – suggesting that co-expression of these two receptors is favored in T cells exposed to tumors. Overall, our findings suggest that TME exposure – likely through TCR-independent factors – directly promote the expression of A2AR in CD8+ T cells. We are currently investigating the nature of the tumor-derived factor(s) promoting this upregulation, as well as the possible role of A2AR/P2RX7 co-expressing tumor-infiltrating CD8+ T cells as effector antitumor cells with longer intratumoral lifespan.
Supported by grants from NIH (R00 AI139381, NIAID).