bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacologic inhibition of liver X receptors enhances T cell anti-tumor function in triple negative breast cancer
Authors: Carpenter Katherine Joyce , Abuirqeba Suomia , Majidi Shabnam , Sengupta Monideepa , Valfort Aurore-Cecile , Chatterjee Arindam , DiPaolo Richard J , Flaveny Colin A. 
Published: January 2023

Abstract
While immunotherapies have demonstrated success in solid malignancies, they have limited efficacy in triple negative breast cancer (TNBC). The liver-X-receptors (LXR) are modulators of metabolism and are known to inhibit pro-inflammatory (Th17 and Th1) and increase anti-inflammatory (Tregs) T-cell differentiation. Colorectal and hematologic cancer cells have also been demonstrated to suppress immune function through production of endogenous LXR agonists. Here we show that targeted suppression of LXR activity using the inverse agonist, SR9243, induces immune-mediated tumor destruction in an orthotopic TNBC model. FACs analysis on tumors revealed a significant increase in Th1 and cytotoxic CD8+ T-cells and a decrease in tumor promoting myeloid derived suppressor cells (MDSCs) in response to SR9243. Intratumor immune cell activation coincided with enhanced dendritic cell (DC) lymph node homing and activity. SR9243 also enhanced Th1 CD4+ and CD8+ cell proliferation in the presence of immune-suppressive tumor conditioned media and cancer cell lysates an in vitro model of the tumor-microenvironment. Metabolic analysis of immune cells exposed to LXR-ligands revealed that LXR activation by tumor-produced ligands or synthetic agonists blocks T-cell glycolytic activity essential to immune cell proliferation and activation in response to tumor antigens. Similarly, we observed that LXR activation disrupts de novo cholesterol synthesis which has been shown to be vital to immune synapse formation between T-cells and DCs. Our results suggest that LXR inverse agonists can be used as immunotherapy drugs to treat TNBC by blocking tumor-induced dysregulation of T-cell metabolism.
Tumor-intrinsic PD-L1 reduces actin cytoskeleton polymerization to promote mTORC1 signals driving tumor stemness
Authors: Kari Suresh Chandra , Kancharla Aravind , Gupta Harshita B. , Risinger April , Curiel Tyler J 
Published: January 2023

Abstract
Tumor-intrinsic PD-L1 signals contribute to tumor virulence and pathology, but mechanisms are poorly understood. We previously showed that tumor-intrinsic PD-L1 increases mTORC1 and tumor initiating cell (TIC) generation and function in ovarian cancer and melanoma. We used CRISPR/Cas9 (KO) and shRNA (lo) to reduce PD-L1 in mouse melanoma (B16) and ovarian cancer (ID8agg), and human ovarian cancer (ES2). PD-L1lo reduced mTORC1 and TIC as expected, but unexpectedly increased actin polymerization and filopodia, and altered cell morphology. The actin depolymerizing agents Latrunculin-A or Cytochalasin-D reversed actin polymerization in PD-L1lo ID8agg cells and increased mTORC1 (p-rpS6) without affecting mTORC2 (pAktS473). Latrunculin-A and Cytochalasin-D increased TIC numbers and stemness gene expression (Oct4) in PD-L1lo ID8agg cells with no effect on control ID8agg cells. Similar actin effects were seen in PD-L1KO B16 and PD-L1KO ES2. To confirm TIC function, Latrunculin-A increased tumorospheres (TIC self-renewal function) in PD-L1lo, but not control ID8agg cells. The mTORC1 inhibitor rapamycin reduced TIC numbers and functions with no effect on actin polymerization, suggesting mTORC1 is downstream of actin polymerization. Rptorlo ID8agg cells (with low mTORC1 signaling) did not exhibit the PD-L1lo actin polymerization, nor did Latrunculin-A increase Rptorlo ID8agg TIC numbers, tumorospheres, or stemness genes, confirming the flow of signals is PD-L1 to actin to mTORC1 to TIC (stemness). Our data define a highly novel tumor virulence control mechanism of cell-intrinsic PD-L1 through inhibiting actin polymerization suggesting new drug discovery targets. Preliminary data show some similar effects of tumor PD-1.
Attenuated Listeria vaccine for cancer immunotherapy expands Vγ2Vδ2 T cells in rhesus monkeys that retain their central memory phenotype and HMBPP responsiveness
Authors: Morita Craig T , Al-Janabi Mohanad Hameed Nada , Workalemahu Grefachew , Wang Hong 
Published: January 2023

Abstract
Human γδ T cells expressing Vγ2Vδ2 TCRs monitor foreign- and self-isoprenoid metabolites to mediate immunity to microbes and tumors. Bisphosphonate treatment of tumors increases isopentenyl pyrophosphate that is sensed by butyrophilin 3A1, allowing Vγ2Vδ2 cells to kill tumors independent of MHC expression or tumor mutational burden. In clinical trials, adoptive immunotherapy with Vγ2Vδ2 cells has few side effects but has resulted in only a few partial and complete remissions. Direct immunization of cancer patients with either a bisphosphonate or bromohydrin pyrophosphate and IL-2, expands Vγ2Vδ2 cells but they rapidly contract, terminally differentiate, and lose responsiveness. Monkeys immunized with zoledronic acid also lost responsiveness. We sought to develop a live bacterial vaccine for Vγ2Vδ2 cells. Listeria monocytogenes (Lm) were attenuated by actA deletion with a mutant PrfA protein (G155S) that increased their virulence. Immunization with attenuated Lm expanded Vγ2Vδ2 cells on secondary immunization that persisted after a third immunization. Vγ2Vδ2 cells retained central memory phenotypes, expressed inflammatory chemokine receptors, and produced IFN-γ without induction of anergy. Expression of PrfA (G155S) was critical because immunization with ΔactA Lm with wild-type PrfA resulted in minimal Vγ2Vδ2 T cell expansions. Similarly, despite high HMBPP levels, immunization with ΔlytB ΔactA prfAwt Lm also resulted in minimal expansions. Thus, Lm stimulation of Vγ2Vδ2 T cells is dependent on their virulence rather than their HMBPP levels. Unlike zoledronic acid, immunization with ΔactA prfAG155S Lm induces large expansions of Vγ2Vδ2 T cells that retain central memory phenotypes and responsiveness.
Immune pressure against ovarian cancer depends on antigen-specific TRM T cells
Authors: Galindo Carmen Maria Anadon , Sanz Jairo Perez , Biswas Subir , Payne Kyle K. , Yu Xiaoqing , Costich Tara Lee , Gonzalez Ricardo Chaurio , Conejo-Garcia Jose R 
Published: January 2023

Abstract
Conventional memory T cells classically include central memory T (TCM) cells, residing in lymphoid organs, and effector memory T (TEM) cells, circulating through various tissues. Recently, a novel population of memory T cells has gained interest, namely tissue resident memory T (TRM) cells, which persist in tissues and do not recirculate. It is described that these cells reside in human tumors playing a role in tumor-specific T-cell responses. We found by flow cytometry that between 50%–80% of the CD8+ T cells in human ovarian carcinomas are CD103+CD69+TRM cells. RNA-seq of TRM and their re-circulating counterparts from 7 different human carcinomas showed a very distinctive phenotype, characterized by co-upregulation of effector (GZMB, IFNG) and exhaustion (PD-1, TIM3) markers, along with transcription factors and signaling molecules likely involved in the acquisition of the TRM phenotype. Unexpectedly, we found very little overlap between the TCR repertoire of both populations in multiple tumors, and TRM T cells consistently showed significantly higher clonality. Tumor antigen-specific TRM T cells intratumorally transferred into syngeneic mice were more effective at delaying tumor growth compared with their tumor antigen-specific recirculating counterparts. Finally, both the acquisition and the maintenance of a TRM phenotype within the CD8 T cell compartment at tumor beds are dependent on exposure to tumor cognate antigen. Together, our data indicate that TRM CD8+ T cells, but not their CD103− counterparts, represent tumor antigen-specific effector lymphocytes actively exerting anti-tumor immune pressure in the ovarian cancer microenvironment.
Epigenetic targeting of Brd4 constrains CD8+ T cell differentiation during infection and cancer
Authors: Milner J Justin , Toma Clara , Omilusik Kyla , Nguyen Hong , Yu Bingfei , Delpoux Arnaud , Yoshida Tomomi , Quon Sara , Dey Anup , Hedrick Stephen M , Ozato Keiko , Crotty Shane , Pipkin Matthew E , Goldrath Ananda W 
Published: January 2023

Abstract
Memory CD8+ T cells afford long-lived, durable protection against infection and malignancy. Despite the critical relevance of memory T cells to vaccination and immunotherapies, the transcriptional and epigenetic signals instructing memory T cell fate remain unclear. Here, we utilized a pooled RNA interference screen to evaluate the activity of transcription factors and chromatin modifiers governing memory T cell differentiation in vivo. The epigenetic ‘reader,’ Brd4 of the BET protein family, emerged as a top regulator of memory T cell differentiation. Through RNA interference, small molecule inhibition and inducible genetic deletion, we established a central role for Brd4 in mediating CD8+ T cell proliferation, differentiation and function during acute viral infection. Brd4 was required for optimal expression of fate-specifying transcription factors, and a deficiency of Brd4 activity resulted in diminished formation of effector memory and CD103+ tissue-resident memory CD8+ T cells. Given that BET inhibition has emerged as a powerful approach for suppressing tumor growth, we also evaluated how BET inhibition and Brd4-deficiency influence T cell activity during cancer. Brd4 was required for intratumoral accumulation and function of T cells in a mouse model of melanoma, and BET inhibition suppressed T cell-mediated control of tumor growth. However, epigenetic targeting of Brd4 constrained terminal differentiation of T cells within tumors, biasing tumor-resident T cells towards a reprogrammable TCF1-expressing phenotype. These studies establish a novel role for Brd4 in CD8+ T cell biology and provide insight for immunotherapy approaches designed to leverage the dynamic activity of CD8+ T cells in tumors.
Therapeutic antibody discovery in lung tumors by B-cell receptor sequencing
Authors: Kramer Kevin J , Raju Nagarajan , Greenplate Allison , Pilewski Kelsey , Massion Pierre , Georgiev Ivelin 
Published: January 2023

Abstract
Malignancies of the lung are expected to be responsible for over 25% of all cancer-associated mortalities in the United States in 2019. Clinical treatment of lung cancer is complicated by both poor detection of early disease activity and relapse or unresponsiveness to administered therapy. Taken together, these realities of patient outcome underscore the need for alternative therapeutic strategies. Research efforts in the cancer immunology field focus primarily on T cells in the tumor microenvironment, however, there is evidence that B cells may impart a clinical benefit in patients. The formation of tertiary lymphoid structures and antibody secretion in lung tumors associate with positive clinical outcomes yet remain understudied and poorly characterized. In an effort to expand upon these observations, we isolated B cells from cryopreserved human lung cancer tissue and recovered B-cell receptor (BCR) sequences by paired heavy and light chain single cell RNA sequencing. From these experiments, we identified clonally expanded B-cell populations and convergent BCR sequences shared between different patients. We further demonstrated that recombinant antibodies derived from lung cancer patients bind cultured lung cancer cell lines in a dose-dependent manner. This preliminary data supports the notion that tumor-resident B-cells secrete functional antibodies that may additionally be tumor-reactive. Future characterization of these antibodies includes antigen identification and the measurement of in vitro and in vivo cytotoxic activity. Human patient-derived antibodies not only could serve as a novel source for therapeutic and diagnostic agents but may also help inform vaccine design in lung cancer indications.
Microbial LPS enhances PD-1 therapy during chronic LCMV infection
Authors: Penaloza-MacMaster Pablo A , Wang Yidan , Eitzinger Simon , Bhattacharyya Mitra , Penaloza-MacMaster Pablo 
Published: January 2023

Abstract
CD8 T cells are critical for controlling intracellular pathogens, but during chronic viral infection, these cells become exhausted and unable to control virus. Programmed cell death-1 (PD-1) blockade therapy partially improves exhausted CD8 T cells during chronic viral infections. However, its limited efficacy in models of chronic infection has precluded its licensure to treat chronic infection. Interestingly, prior studies show that certain microbiota can improve PD-1 therapy, but the specific microbial components that mediate this positive effect remain unknown. In this study, we interrogated whether microbial LPS could enhance PD-1 therapy during chronic viral infection. Using the model of chronic lymphocytic choriomeningitis virus (LCMV) infection in mice, we show that sublethal doses of LPS followed by PD-1 therapy results in synergistic improvement of virus-specific CD8 T cells in blood and tissues (~10-fold greater compared to PD-1 therapy alone). We show that the improvement of PD-1 therapy by LPS is dependent on reinforced B7/CD28 costimulation and is mediated by a dendritic cell intrinsic mechanism. Although LPS has safety concerns, prior studies show that low LPS doses (≤4 ng/kg) are well-tolerated in humans, demonstrating that there is a threshold of natural resistance to this microbial product. Altogether, our data suggest an unexpected role for LPS/TLR4 signaling in modulating response to PD-1 therapy. Our findings may be important for improving immune checkpoint therapy against chronic infections and for understanding how microbial products modulate responses to therapy.
Monocytes and macrophages limit systemic infection and modulate the CD4 T cell response during Zika virus infection in mice
Authors: Wang Ying-Ting , Hattakam Sararat , Young Matthew Perry , Regla-Nava Jose Angel , Shresta Sujan 
Published: January 2023

Abstract
Monocytes and macrophages are antiviral innate immune effector cells that also serve as cellular hosts of Zika virus (ZIKV). To investigate the precise role of monocytes and macrophages during ZIKV infection in vivo, monocytes and macrophages were depleted with clodronate liposomes before ZIKV infection in wild-type C57BL/6 mice, and viral burden and ZIKV-specific immune responses were assessed. Chlodronate liposometreated mice had higher level of ZIKV RNA in the serum and spleen relative to control liposome-treated mice at early time points after infection. At later time points after infection, chlodronate liposome-treated mice developed an impaired ZIKV-specific Th1 response in terms of both magnitude and quality, whereas they exhibited enhanced Tfh, germinal center B cell, plasma cell, and neutralizing antibody responses as compared to control liposome-treated mice. These data indicate that monocytes and macrophages limit ZIKV dissemination and regulate the balance between Th1 versus Tfh responses during ZIKV infection. Thus, monocytes and macrophages contribute to both the innate control of ZIKV infection and regulation of the adoptive immune response.
Identification of specific T lymphocytes against to an IFNg inducible lysosomal thiol reductase (GILT)-dependent, class II MHC-associated epitope in GILT−/− mice
Authors: He Xiao , Dai Hu , Reyes-Vargas Eduardo , Jensen Peter E 
Published: January 2023

Abstract
IFNγ inducible lysosomal thiol reductase (GILT) is the only thiol reductase localized in lysosomes and late endosomes, with its optimal activity at acidic pH. GILT is constitutively expressed in professional APC, further upregulated by IFNγ, and participates in Ag processing by catalyzing disulfide (S-S) bond reduction in proteins thus facilitating unfolding of native S-S bond containing Ag for further processing. It was reported that GILT−/− mice mounted significantly reduced T cell proliferative responses to S-S bond-containing protein Ags in vitro, but responded normally to a non-S-S bond containing protein. In addition, GILT−/− APC showed a selective deficiency in presenting some cysteine-containing epitopes within a model protein Ag, hen egg white lysozyme. Using HPLC-MS/MS, we first identified one group of unique GILT-dependent, class II MHC-associated peptides from B6 mice, but not from GILT−/− mice. Binding of these GILT dependent, class II MHC-associated peptides to I-Ab proteins was confirmed in vitro. Furthermore, T cells specific to one of the unique GILT-dependent peptides, BP7, was detected in GILT−/− mice, but not found in B6 mice. BP7 peptide specific T cell hybridoma clones were established as well. Taken together, our results indicate that GILT−/− mice have a deficiency in generation of certain T cell epitopes due to loss of GILT activity. Missing of GILT dependent epitopes might lead to survival of the T cells specific to these GILT-dependent epitopes (escaping from the negative selection) in thymus of GILT−/− mice. We are in progress of cloning the BP7 specific TCRs from T cell hybridoma clones. The potential role of the BP7 specific T lymphocytes in autoimmunity will be examined in BP7 specific T cell retrogenic mice.
Mast Cells in Patients with Hereditary α-Tryptasemia Promote HLA-DR Expression and a Th2-Polarizing Microenvironment in the Gastrointestinal Tract
Authors: Shirley James Forrest , Drourr Joshua , Edwards W. Taylor , Tuna Kubra , Ryan Lisa K , Alli Abdel , Tang Ying , Glover Sarah C. 
Published: January 2023

Abstract
Hereditary α-tryptasemia (HαT) is a recently identified, genetic disorder characterized by multisystem comorbidities resulting from increased monoallelic α-tryptase copy number (CN) at TPSAB1 (α-TPSAB1). Affected individuals frequently exhibit heterogeneous multisystem symptoms and comorbidities which negatively impact daily functioning and quality of life. In the cohorts examined thus far, functional dyspepsia and irritable bowel syndrome, were most frequently reported. However, the mechanism by which increased α-TPSAB1 CN produces GI disease is unknown.
Tryptase is almost exclusively produced by mast cells (MC). In the gut, MC play important roles in immune responses, leukocyte recruitment, neuroimmune inflammation, and tissue repair. MC can also promote T-cell activation and polarization via cytokine secretion, co-stimulatory marker expression and MHC II antigen presentation. MCs also release exosomes, nanosized vesicles secreted by most cell types present in biological fluids such as blood, cerebrospinal fluid, and urine, which have a reported influence on T cell differentiation.
In early experiments, we found increased numbers of GI MCs, activated T cells, and urinary exosomes in HαT patients compared to healthy donors. Thus, we evaluated MC surface antigen expression, exosome proteomics, and cytokine expression of exosome-treated T cells. We found increased HLA-DR and FcɛR1α expression in HαT-patient GI MCs, increased Th2 associated signaling proteins in HαT urinary exosomes, and elevated Th2 cytokine expression in HαT-exosome treated T cells. These results suggest that HαT GI morbidity involves aggravated MC hyperplasia and antigen presentation which promotes T cell activation and Th2 polarization.
Intestinal epithelial cells differentiated from iPS cells (iPS-IECs) suppressed bacterial translocation in an organ model of alcohol-induced intestinal epithelial dysfunction
Authors: Ito Ichiaki , Jacob Sam , Suzuki Sumihiro , Kobayashi Makiko , Suzuki Fujio 
Published: January 2023

Abstract
Microbiota translocated from the intestine causes infectious complications in alcoholics, frequently. In the present study, the effect of iPS-IEC transplantation on gut-associated bacterial translocation was investigated in an organoid model of intestinal epithelial burrier (IEB) dysfunction in patients with alcohol use disorder. iPS-IECs (a mixture of Paneth cells, goblet cells, enteroendocrine cells, and enterocytes) were differentiated from iPS cells, originated from human peripheral CD38+ hematopoietic stem cells. Human gut organoids (HGO) were generated from iPS cells in 3D cultures for 2 weeks. HGO were alcoholized with 0.2% ethanol for 2 weeks (A/HGO). iPSIECs (5 × 103 cells) were co-cultured with 100 A/HGO for 3 days. IEB functions of A/HGO were tested by severities of Enterococcus faecalis (E. faecalis) invasion into the organoids. The gene expressions of tight junction proteins and intestinal cell markers of A/HGO were determined by real-time PCR and Western blotting. In the results, E. faecalis added to culture media invaded the A/HGO, while the pathogen did not invade the HGO in the same cultures. However, the pathogen did not invade the A/HGO co-cultured with iPS-IECs. Reduced expression of tight junction protein mRNAs was shown in A/HGO, while these mRNAs were expressed in A/HGO co-cultured with iPS-IECs. LGR5 and NOTCH1 gene expressions in A/HGO were shown to be a minimum, while these genes were expressed sufficiently in A/HGO co-cultured with iPS-ICs. These results indicate that the alcohol-induced IEB dysfunction of A/HGO is significantly improved in cultures added with iPSIECs.
IFNγ and poly(I:C) primed MSCs enhances the therapeutic effects on DSS induced colitis via enhancing indoleamine 2, 3-dioxygenase and inducing regulatory T cell phenotype
Authors: Lim Ji-Young , Ryu Da-Bin , Lee Sung-Eun , Park Gyeongsin , Min Chang-Ki 
Published: January 2023

Abstract
Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the colon and small intestine caused by chronic and excessive inflammation. Mesenchymal stem cells (MSCs) are pluripotent cells with immunosuppressive properties, currently studied as a potential treatment for IBD. We previously demonstrated that among various TLR ligands, MSCs treated with poly(I:C), which is a TLR3 ligand, more profoundly induced IDO, which is a therapeutically relevant immunosuppressive factor, without any observable phenotype change in vitro. The goal of the study was to determine whether poly(I:C) can enhance the therapeutic efficacy of bone marrow-derived MSCs for the treatment of IBD. To compare the therapeutic effects between naïve MSCs and primed MSCs by poly(I:C) stimulation on murine colitis, mice (C57BL6) were administered with 2.5% dextran sodium sulfate (DSS) in drinking water for 5 days and injected with MSCs intraperitoneally on days 1 and 3 following DSS ingestion. The disease activity index (DAI) score and body weight loss were significantly improved in the primed MSCs treated mice group. Also the pathologic severity of colon were more recovered in primed MSCs treated group. The frequency of T cells in spleen and mesenteric lymph node was markedly decreased in primed MSCs treated group. Foxp3 expressing regulatory T cells were more expanded in primed MSCs treated group. Treatment of primed MSCs reduced the expression of proinflammatory cytokines in colon tissue.
In conclusion, we demonstrate that primed MSCs with poly(I:C) improve their efficacy in treating DSS-induced colitis, and this effect at least partly depends on the enhancement of their immunosuppressive activity through increasing their production of IDO.