bluuebunny/crossref_metadata_2025_split huggingface dataset:
IL-1β secreted by macrophages in response to commensal bacteria acts together with bone morphogenetic protein signals to increase hepcidin expression in hepatocytes (MUC5P.758)
Authors: Cherayil Bobby , Shanmugam Nanda 
Published: January 2023

Abstract
Elevated expression of the iron regulating hormone hepcidin leads to abnormalities of iron metabolism in inflammatory diseases. The mechanisms involved in inflammation-associated hepcidin upregulation are not well understood. We have shown in mouse IBD models that the commensal microbiota significantly influences hepcidin expression. Here we describe experiments to elucidate how commensal bacteria upregulate hepcidin. Differentiated THP-1 macrophages were infected with the commensal Bifidobacterium infantis. Sterile supernatants of the infected, but not uninfected, THP-1 cells increased hepcidin expression in HuH7 human hepatocytes, whereas direct infection of HuH7 cells failed to induce hepcidin. The infected THP-1 cells secreted IL-1β, neutralization of which significantly inhibited induction of hepcidin expression in the HuH7 cells. Pretreatment of the HuH7 cells with inhibitors of the bone morphogenetic protein (BMP) signaling pathway also prevented the upregulation of hepcidin by the supernatant of B. infantis-infected THP-1 cells. Our findings demonstrate that IL-1β secreted by macrophages in response to commensal bacteria can induce increased expression of hepcidin in hepatocytes. An activator of the BMP signaling pathway is also involved but the identity and source of this molecule are yet to be determined. Furthermore, our results suggest that neutralization of IL-1β may be useful in preventing or treating the dysregulation of iron homeostasis associated with IBD.
Selective inhibition of Kv1.3 channels in memory T cells by targeted delivery with nanoparticles suppresses CD40 ligand expression in SLE (THER5P.908)
Authors: Chimote Ameet , Hajdu Peter , Kottyan Leah , Harley John , Conforti Laura 
Published: January 2023

Abstract
The pathogenesis of Systemic Lupus Erythematosus (SLE) is characterized by hyperactive memory T cells (TM). In SLE, the TM cells show a Ca2+-dependent increase in the costimulatory CD40 ligand (CD40L) which binds CD40 on B cells, resulting in B cell activation and autoantibody production. CD40L is widely recognized as a potential target for developing new therapies for SLE. Cytosolic Ca2+ levels, which increase during T cell activation and mediate CD40L expression, are regulated by Kv1.3 channels. We have developed lipid nanoparticles that can deliver Kv1.3 siRNAs (Kv1.3-NPs) selectively to TM cells and decrease the activation-induced Ca2+ influx (Hajdu et al., Biomaterials 2013). We studied whether these Kv1.3-NPs decrease the Ca2+-dependent overexpression of CD40L in SLE peripheral blood TM cells. We observed that nuclear translocation of NFAT, a transcription factor upstream to CD40L, in activated TEM cells was reduced by ~50% after treatment with Kv1.3-NPs. Furthermore, Kv1.3-NP treatment selectively reduced CD40L expression in activated TEM cells by ~40% in healthy donors and ~60% in SLE patients, while CD40L levels remained unchanged in cells that did not incorporate the nanoparticles. Interestingly, we observed that treatment with Kv1.3-NPs in SLE patients resulted in T cell phenotype switching from a predominantly TM phenotype to a naïve phenotype. Our findings open the possibility of using Kv1.3-NPs as potential targeted immune suppressive therapeutic agents in SLE.
Time-lapse imaging of contact dynamics between mesenchymal stem cells and T cells (THER5P.913)
Authors: Pyo Minji , Lee Hong Kyung , Uhm Jinbum , Ryu Hwa Sun , Hong Jin Tae , Kim Youngsoo , Han Sang-Bae 
Published: January 2023

Abstract
Mesenchymal stem cells (MSC) ameliorate the pathogenesis of systemic lupus erythematosus through inhibiting T cell functions via soluble mediators and direct cell-cell contact. However, little is known about the contact dynamics at the single cell level. Using time-lapse imaging, we show that their contact is dependent on CCL2, but not CCL3, CCL4, CXCL10, and CXCL12, which are produced by MSCs. First, we analyzed contact dynamics of MSCs. Each WT MSC contacted 11 T cells and each contact lasted 107 min. In the same condition, each CCL2-/- MSC contacted 10 T cells and each contact continues 34 min. Subsequently, CCL2-/- MSCs did not inhibit T cell functions. Next, we analyzed migration dynamics of only T cells, since MSCs did not move well. When calculating the percentage of T cells contacting MSCs more than one time for 6 h, 68% T cells contacted MSCs and 59% T cells contacted CCL2-/- MSCs. T cells moved at average speeds of 7 um/min without contact and did not move well during the contact period, which was similar in cultures with either WT or CCL2-/- MSCs. Together, our data demonstrate that MSC-derived CCL2 might increase T cell migration, prolong contact duration with T cells, and finally inhibit T cell functions.
Antigen specific tolerance and the prevention of autoimmune type 1 diabetes occurs through indirect antigen presentation and requires programmed death ligand 1 (THER5P.918)
Authors: Spanier Justin , Heffernan James , Mitchell Jason , Pauken Kristen , Sahli Nathanael , Fife Brian 
Published: January 2023

Abstract
Antigen-coupled ethylene carbodiimide-fixed cells is an attractive therapeutic platform for treating human patients with type 1 diabetes since these cells can prevent and reverse diabetes in the non-obese diabetic mouse model of diabetes. However, the mechanisms contributing to the induction of T cell tolerance in vivo following treatment are unclear. Therefore, we used the BDC2.5 T cell transfer model to study how p31-coupled cells inhibit T cell function in vivo. Our results demonstrate that indirect antigen presentation was critical for tolerance induction in vivo. We further demonstrate that PD-L1 on the host antigen presenting cells is required for tolerance induction. Importantly, using two-photon microscopy we show that BDC2.5 T cells arrest on CD11c+ dendritic cells during the induction of tolerance, suggesting that these cells are responsible for presenting coupled cell antigen and tolerance induction. To increase the feasibility of translating antigen coupled cells to the clinic, we demonstrate that whole blood preparations and frozen cells are sufficient for tolerance induction, a significant concern for donor coupled cell sources when considering translation to human patients. These data further our understanding of how antigen-coupled cells induce tolerance and how this tolerance protocol could be altered to increase clinical feasibility.
MHC class II-disparate heart but not skin allografts accelerate recipient cardiovascular disease (TRAN1P.934)
Authors: Zhou Jing , yi tai , Qin Lingfeng , Ali Rahmat , Li Qingle , Jiao Yang , Li Guangxing , Zhang Jiasheng , Sadeghi Mehran , Pober Jordan , Tellides George 
Published: January 2023

Abstract
Organ transplantation is the most effective therapy for patients with end-stage organ failure but is limited by premature deaths from cardiovascular disease (CVD). The underlying mechanism is poorly understood. Using the ApoE-/- mouse model of atherosclerosis we investigated the effect of allograft rejection on recipient CVD by transplanting MHC class II-disparate cardiac or skin allografts from BM12 donor mice into C57BL/6 (B6) ApoE-/- recipient mice. Isografts from B6 donor mice were used as controls. Mice were observed for 12 weeks post transplantation. Allograft rejection of the BM12 hearts occurred around 60 days whereas the skin allografts were rejected within 15 days. About half of the mice with cardiac allografts died before 12 weeks although all mice with the skin grafts or heart isografts survived. The mice of heart allografts exhibited impaired cardiac function (decreased fractional shortening and enlarged left ventricles) and larger atherosclerotic lesions compared with those of cardiac isografts or skin grafts. CD4 T cells from blood and atherosclerotic lesions expressed higher levels of the early activation marker CD69 in hosts of heart allografts but not in those of isografts or skin allografts. Only the mice with cardiac allografts showed elevated mRNA levels for IFN-γ and IL-12a in their native hearts. Our data indicate that chronic allorecognition by alloreactive CD4 T cells elicits sustained inflammation and plays a key role in promoting recipient CVD.
Reduced and skewed TCR Vβ repertoire in CD8 compared to Foxp3+ regulatory T cells in acute gastrointestinal graft versus host disease (TRAN1P.947)
Authors: Tran Dat , Maher Ossama , Rivas Charlotte , Moree Shannon 
Published: January 2023

Abstract
It is unclear if skewing of TCR repertoire in CD4, CD8 and Foxp3+Tregs plays a role in acute gastrointestinal (GI) GVHD. This prospective clinical study examined the TCR Vβ diversity among CD4, CD8 and Foxp3+Tregs from 18 adult patients (median age 53) post allogeneic stem cell transplant (SCT) at day 80 with acute GI GVHD (giGVHD, &gt;grade 1, n=9) vs. nonGVHD (n=9). Fresh PBMC were analyzed by FACS using IOTest Beta Mark 24 TCR Vβ and Foxp3 (236A/E7)/Helios eBioscience kits. Mann Whitney test was used. Mean %CD4 was lower in giGVHD vs. nonGVHD (44vs72%, p=0.02) while no difference in %CD8 (51vs55%), %Tregs (16vs16%) and %Helios+Tregs (72vs76%). %Total Vβ were similar for CD4 (60), CD8 (60) and Tregs (64) in nonGVHD. In giGVHD, %CD8 (40) was lower than %Tregs (69), p&lt;0.001 and %CD4 (56), p=0.08. Between giGVHD vs. nonGVHD, there was a difference for %TCR in CD8 (p=0.02) but none for CD4 or Tregs. In nonGVHD, there was a direct correlation between %CD8 TCR vs. %CD8 and %CD4 TCR vs. %CD4 but no correlation for %Treg TCR vs. %Tregs. In giGVHD, there was an inverse correlation between %CD8 TCR vs. %CD8 and %CD4 TCR vs. %CD4 but no correlation for %Treg TCR vs. %Tregs. These results indicate a restricted, reduced and skewed TCR repertoire within the CD8 as compared to Tregs and CD4 in giGVHD. These CD8 might be the pathogenic cells escaping Treg suppression. In conclusion, a reduced and skewed TCR diversity in CD8 at day 80 might be predictive for the development of chronic GVHD.
Effect of chemotherapy on the myeloid-derived suppressor cells percentages in the peripheral blood of advanced non-small cell lung cancer patients (TUM6P.965)
Authors: Vetsika E. , Gioulmpasani Marianthi , Skalidaki Eirini , Katsarou Afroditi , Koinis Filippos , Aggouraki Despoina , Koutoulaki Anna , Mavroudis Dimitris , Georgoulias Vassilis , Kotsakis Athanasios 
Published: January 2023

Abstract
In our previous study, high levels of one granulocytic (G-MDSC) and two monocytic (M-MDSCs) subpopulations of immunosuppressive MDSCs were found and their overexpression was correlated with worse prognosis in NSCLC patients. Using flow cytometry, the impact of chemotherapy on the percentages and functionality of M-MDSC (CD14+CD15-CD11b+CD33+HLA-DR-Lin- and CD14+CD15+CD11b+ CD33+HLA-DR-Lin-) and G-MDSC (CD14-CD15+CD11b+CD33+HLA-DR-Lin-) was evaluated in the peripheral blood of patients (n=141) prior to chemotherapy and after the 3rd and 6th cycle of treatment. The M-MDSC (CD14+CD15-CD11b+CD33+HLA-DR-Lin-) percentages were found significantly decreased post chemotherapy compared to baseline, whereas chemotherapy had no effect on CD14+CD15+CD11b+CD33+HLA-DR-Lin- M-MDSCs. In contrast, the production of iNOS by M-MDSCs was significantly increased compared to the baseline. Both G-MDSC levels and their ROS expression were not affected by chemotherapy. In addition, both subtypes of MDSCs, when co-cultured with CD3+ T cells, were able to significantly suppress IFN-γ secretion by T cells. Finally, the M-MDSC (CD14+CD15-CD11b+CD33+HLA-DR-Lin-) percentages were found significantly decreased in patients that did not develop progressive disease during or after treatment completion, compared to patients with disease progression. Chemotherapy seems to have an impact on MDSC expression and functionality, hence targeting these cells may lead to a better clinical outcome in NSCLC patients.
A translational study of monocyte receptor expression and chemotaxis between dogs and humans with and without osteosarcoma (TUM6P.975)
Authors: Fogle Jonathan 
Published: January 2023

Abstract
Spontaneous canine osteosarcoma (OSA) is an excellent translational model for human OSA. Published reports of both canine and human OSA indicate that monocyte activation is important for controlling primary and metastatic disease. The purpose of this study was to identify phenotypic and chemotactic differences between monocytes from dogs with OSA, healthy dogs and to determine if the same findings occur in human OSA. Canine peripheral blood mononuclear cells (PBMCs) were incubated with antibodies against CD14, CD32, CD62L, CD16, CD11c, CCR2, CCR7, CD43, CX3CR1, and CXCR2 and analyzed by flow cytometry. In OSA dogs (n=18), CD16 surface expression was increased, and CD62L, CCR2, CCR7, CD43, CX3CR1 and CXCR2 expression was decreased, compared to controls (n=13, p&lt;0.01, MWU). Additionally, decreased chemokine receptor expression was associated with increased peripheral blood monocyte counts. Preliminary data from human OSA patients suggests the monocyte receptor expression profile is similar to that in canine OSA. Based upon these results, we hypothesize that monocytes exhibit altered chemotaxis in OSA patients. Assessment of in vitro monocyte chemotaxis in healthy patients compared with OSA patients, in both dogs and humans, is currently underway.
Colorectal tumour associated macrophages are more pro-inflammatory than adjacent control bowel tissue macrophage populations (TUM6P.1003)
Authors: Kemp Roslyn , Norton Samuel , Taylor Edward , Dunn Elliott , Munro Fran , Black Michael , McCall John 
Published: January 2023

Abstract
Infiltration of macrophages in colorectal cancer is associated with patient prognosis. Using multiparameter flow cytometry, multiple distinct macrophage populations were detected in tumour tissue recovered from colorectal cancer patients, highlighting the heterogeneity of myeloid populations within complex tissues. Population frequencies of five key macrophage populations were assessed in tumour and matched non-transformed bowel tissue to reveal specific changes caused by the direct presence of the tumour. The frequency of conventional (pro-inflammatory) macrophages (CD45+CD11b+CD33-CD64+CD14-CD206+CD163-) was significantly increased in tumour tissue compared to healthy bowel tissue. This population was analogous to pro-inflammatory IL-12-producing macrophages derived in vitro from blood. A large population of gut resident macrophages was also observed in both tumour and control bowel tissue. “Homeostatic” gut resident macrophages (CD45+CD33+CD14-CD11b-CD64-) and “inflammatory” gut resident macrophages (CD45+CD33+CD14+CD11b+CD64+) were decreased and increased, respectively, in tumour tissue compared with healthy bowel tissue of the same patients. This suggests that macrophages provide a pro-inflammatory environment within the tumour tissue and may explain why these cells are often associated with improved patient outcome in colorectal cancer. Data gained from this study could be used for future investigation of macrophages as both prognostic and therapeutic targets.
Use of [11C]PBR28 to localize and quantify tumor associated macrophages in pancreas cancer (TUM6P.1008)
Authors: Perusina Lanfranca Mirna , Pasca Di Magliano Marina , Piert Morand , Zou Weiping , Frankel Timothy 
Published: January 2023

Abstract
Tumor associated macrophages (TAM) are an important part of the immune microenvironment in pancreas cancer (PC) and are associated with poor prognosis. We investigated the use of a novel radiolabeled small molecule ([11C]PBR28), which binds to the macrophage translocator protein (TSPO), to track TAMs in-vivo. A murine PC line was generated from a KRAS/P53 mutant transgenic mouse. Immunoblotting confirmed lack of endogenous TSPO expression. After subcutaneous implantation, mice were administered [11C]PBR28. After micro-PET imaging, organs and tumors were harvested for autoradiography. Immunoflourescent co-staining of tumors confirmed TAM infiltration with co-expression of F4/80 and TSPO. Following [11C]PBR28 injection, micro-PET successfully localized tumors and autoradiography demonstrated a 3-fold increase in tumor radioactivity compared to background (muscle). To confirm the observed activity was TAM specific, the experiment was repeated in CD11b+ diphtheria toxin receptor (DTR) transgenic mice. After tumor inoculation, diphtheria toxin (DT) was administered and macrophage depletion confirmed by immunofluorescence and flow cytometry. Autoradiography demonstrated equal tumor uptake relative to background and decreased levels compared to tumors from wild-type mice. We demonstrated a non-invasive method to quantify pancreatic cancer TAM infiltration in-vivo using a novel radiotracer. This could be used prognostically and to determine response to TAM based immunotherapy.
Unusual immunogenicity of live cancer cells (TUM6P.957)
Authors: Das Mohapatra Alok , Tirrell Isaac , Srivastava Pramod 
Published: January 2023

Abstract
The ability of irradiated tumor cells to elicit tumor immunity has been widely established. Using two murine tumor models, we observe that injection of about 20,000 live tumor cells fails to develop tumors in recipient mice. (About ten times that dose leads to a successful tumor implantation.) However, mice injected with this sub-tumorigenic dose of cells become resistant to a subsequent lethal challenge. Remarkably, as many as 20 million (M) irradiated tumor cells (i.e. 1,000 times the sub-tumorigenic dose) are required to elicit resistance to tumor challenge. We assumed that the live cells in the sub-tumorigenic dose multiply in vivo and generate a large immunizing dose, before they are rejected. Indeed, imaging in vivo of the mice challenged with the sub-tumorigenic dose revealed that the tumor cells multiply at the site of challenge ~100 fold to ~2M cells over a week followed by a rapid decline. Thus the total antigen load in a sub-tumorigenic live inoculum (2M cells) is still only about 10% of the antigenic load in an irradiated cell inoculum (20M cells). While we explore the mechanisms of the unusual immunogenicity of live cells, we presently conclude (i) that higher immunogenicity is not a direct function of antigen load, and (ii) live cells cross-prime the naïve T cell response in a way that is distinctly different from, and more efficient than irradiated cells.
Myeloid dendritic cell-specific mTORC2 deficiency enhances Th1 and Th17 cell responses and inhibits B16 melanoma growth (TUM6P.959)
Authors: Raich-Regue Dalia , Rosborough Brian , Fabian Kellsye , Turnquist Heth , Storkus Walter , Thomson Angus 
Published: January 2023

Abstract
The mechanistic/mammalian target of rapamycin (mTOR) is a key integrative kinase that functions in at least two independent complexes: mTOR complex (C)1 and mTORC2. While mTORC2 in T cells promotes Th2 differentiation, its immunologic function in dendritic cells (DC) is largely unknown. We defined the role of rictor, a key mTORC2 component, in myeloid DC and their ability to polarize allogeneic T cells. When stimulated with TLR ligands, bone marrow-derived DC generated from conditional Rictor knockouts displayed lower co-inhibitory B7-H1 (CD274) molecule expression, enhanced IL-12p70, IL-23, IL-6 and TNFα production and augmented allogeneic T cell stimulatory ability. Analysis of antigen-specific CD4+ T cells after activation by Rictor-/- DC in vivo revealed significant expansion of IFN-γ+ and IL-17+, but not IL-10+ or CD4+Foxp3+ T cells. Consistent with this pro-inflammatory effect, intratumoral injection of Rictor-/- DC markedly slowed B16 melanoma growth in B6 WT mice compared to control DC (p&lt;0.05), promoting enhancement of CD4+IL-17+ and CD8+INFγ+ T cells in the spleens of Rictor-/- DC treated animals compared with controls. These data indicate that DC lacking mTORC2 activity exhibit an enhanced pro-inflammatory profile with ability to promote Th1/Th17 responses and slowed melanoma progression versus control DC. Therefore, targeting mTORC2 provides new insight into molecular regulation of DC function with therapeutic implications for cancer.
Dectin-1 activation subverts the suppression of myeloid-derived suppressor cells by inducing PMN-MDSC apoptosis and monocytic MDSC differentiation to potent antigen-presenting cells in cancer (TUM6P.961)
Authors: Albeituni Sabrin , Ding Chuanlin , Liu Min , Hu Xiaoling , Luo Fengling , Yan Jun 
Published: January 2023

Abstract
Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature myeloid cells that promote tumor progression. Herein, we demonstrate that activation of a C-type lectin receptor, dectin-1, in MDSC differentially modulates the function of different MDSC subsets. Yeast-derived particulate β-glucan (WGP), a ligand to engage dectin-1, oral treatment in vivo significantly decreases tumor weight and splenomegaly in tumor-bearing mice by reducing the accumulation of PMN-MDSC but not M-MDSC in spleens and tumors, and decreases PMN-MDSC suppression in vitro through the induction of respiratory burst and apoptosis. On a different axis, WGP-treated M-MDSC differentiate into F4/80+CD11c+ cells that can uptake and present OVA antigen to OVA-specific CD4+ T cells and cross-present antigen to OVA-specific CD8+ T cells in a dectin-1 dependent manner. In addition, ERK1/2 phosphorylation is required for the acquisition of APC properties in M-MDSC, since M-MDSC treated with ERK inhibitor and WGP do not differentiate into APC. Moreover, WGP-treated M-MDSC do not promote tumor growth in vivo when inoculated subcutaneously with LLC cells. Interestingly, patients with non-small cell lung cancer (NSCLC) that received WGP treatment prior to any treatment for two weeks had a decreased frequency of CD14-HLA-DR-CD11b+CD33+ in the peripheral blood. Overall, these data indicate that WGP may be a potent immune modulator of MDSC suppressive function and differentiation in cancer.
Carcinoembryonic antigen signaling suppresses the activation of human T cells by a SHP-independent mechanism : a potential mechanism for tumor-mediated suppression of T cell immunity. (TUM7P.1025)
Authors: Bae Eun-ah , Lee Kyoo A , Song You Chan , Kang Chang-Yuil 
Published: January 2023

Abstract
Carcinoembryonic antigen (CEA) is a well-known tumor antigen that is found in the serum of patients with various cancers and is correlated with an increased risk of cancer recurrence and metastasis. To understand the tumor environment and to develop anti-tumor therapies, carcinoembryonic antigen has been studied as an antigen to activate/tolerate specific T cells. In this study, we show that carcinoembryonic antigen can function as a co-inhibitory molecule and can inhibit the activation of human PBMC-derived T cells. Addition of CEA-overexpressing tumor cells or immobilized CEA dampened both cell proliferation and the expression of IL-2 and CD69 expression in T cells after TCR stimulation. The phosphorylation of ERK and translocation of NFAT were hampered in these cells, while the phosphorylation of proximal TCR signaling molecules such as ZAP70 and PLCγ was not affected by immobilized CEA. To determine the relevance of CEACAM1 and SHP molecules to carcinoembryonic antigen-mediated suppression, we tested the effect of the SHP inhibitor, NSC-87877 on carcinoembryonic antigen-mediated suppression of T cells, but it did not reverse the effect of carcinoembryonic antigen. Collectively, these results indicate that carcinoembryonic antigen can function as a modulator of T cell responses suggesting a novel mechanism of tumor evasion.