bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of Bcl-3 in T cells upon challenge with lymphocytic choriomeningitis virus
Authors: Jaiswal Hemant , Siebenlist Ulrich 
Published: January 2023

Abstract
Bcl-3 is an atypical member of the IkB family. Classical IkBs inhibit trans-activating NF-kB dimers such as p50/RelA largely via cytoplasmic retention; they are degraded in response to many signals, which allows nuclear entry of NF-kB. By contrast, Bcl-3 is not degraded and acts in the nucleus to modulate transcription of NF-kB target genes by associating with p50/NF-kB1 and p52/NF-kB2 homodimers. The latter complexes do not trans-activate by themselves, and association with Bcl-3 may promote or inhibit transcription in a highly gene- and context-dependent manner. Bcl-3 has profound biologic roles. It is associated with recurrent translocations in some B-cell tumors and Bcl-3−/− mice exhibit notably impaired adaptive and innate immune responses. Previously, we have shown that Bcl-3 regulates plasticity and pathogenicity of autoimmune CD4 T cells in the T cell transfer-induced colitis model as well as in EAE, a model for multiple sclerosis. However, the detailed molecular controls of Bcl-3 in T cell differentiation and its antigenic responses are not well understood. To evaluate the possible role of Bcl-3 in antigen-specific T cell responses, mice lacking Bcl-3 specifically in T cells were challenged with acute lymphocytic choriomeningitis virus (LCMV) infection. Preliminary data revealed that Bcl-3−/− CD8 T cells had comparable primary antiviral responses at day 8 post infection. However, loss of Bcl-3 in T cells significantly reduced the proportion of LCMV-specific CD8 T cells in spleens 6 weeks post infection. This suggests a crucial role of Bcl-3 in long-term maintenance of antigen-specific CD8 T cells. We will present initial investigations into mechanisms by which Bcl-3 may help to maintain antiviral T cell responses over time.
Inflammatory monocytes hinder antiviral B cell responses
Authors: Kuka Mirela , Sammicheli Stefano , Di Lucia Pietro , De Oya Nereida Jimenez , De Giovanni Marco , Fioravanti Jessica , Cristofani Claudia , Maganuco Carmela G. , Fallet Benedict , Ganzer Lucia , Sironi Laura , Mainetti Marta , Ostuni Renato , Larimore Kevin , Greenberg Philip D. , de la Torre Juan Carlos , Guidotti Luca G , Iannacone Matteo 
Published: January 2023

Abstract
Antibodies are critical for protection against viral infections. However, several viruses, such as lymphocytic choriomeningitis virus (LCMV), avoid the induction of early protective antibody responses by poorly understood mechanisms. We analyzed the spatiotemporal dynamics of B cell activation to show that, upon subcutaneous infection, LCMV-specific B cells readily relocate to the interfollicular and T cell areas of draining lymph nodes, where they extensively interact with CD11b+Ly6Chi inflammatory monocytes. These myeloid cells were recruited to lymph nodes draining LCMV infection sites in a type I interferon– and CCR2-dependent fashion, and they suppressed antiviral B cell responses by virtue of their ability to produce nitric oxide. Depletion of inflammatory monocytes, inhibition of their lymph node recruitment, or impairment of their nitric oxide–producing ability enhanced LCMV-specific B cell survival and led to robust neutralizing antibody production. Our results identify inflammatory monocytes as critical gatekeepers that restrain antiviral B cell responses and suggest that certain viruses take advantage of these cells to prolong their persistence within the host.
Type I IFN mediates cell-intrinsic host protective effects during acute gram-negative bacterial infection of macrophages
Authors: Dorrington Michael G , John Sinu , Fraser Iain D.C. 
Published: January 2023

Abstract
Many bacteria require entrance into host immune cells, such as macrophages, in order to replicate. These intracellular bacteria have evolved complex strategies for avoiding the antimicrobial programming of these immune cells to create replicative niches. While we know a great deal about various virulence factors deployed by intracellular bacteria as well as how cells try to kill these pathogens, how bacteria and host cells modulate each others’ responses during infection is less well understood.
Using the Gram-negative bacteria Burkholderia cenocepacia, we have uncovered a negative relationship between type I IFN signaling and the replicative potential of invading bacteria. Firstly, cells infected with these bacteria produce significant levels of IFN as well as the products of IFN-stimulated genes (ISGs). Cells pre-treated with IFNβ are less permissive to bacterial replication, while cells from mice lacking the type I IFN receptor (IFNAR) have increased levels of bacterial replication compared to wild-type cells. Interestingly, this phenotype is type I IFN-specific, as pre-treatment with IFNγ has no effect on bacterial replication. Additionally, siRNA knockdown of select ISGs, such as IFIT1, leads to increased bacterial replication within macrophages. A rigorous, concurrent transcriptomic profiling of both infected cells and intracellular bacteria is providing insight into how the bacteria and their host cells interact with one another during acute infection, providing a basis for targeted CRISPR-based screening experiments to unravel critical regulators of the host-pathogen interaction.
IL-27 limits neutrophil mediated pathology during pulmonary infection with Cryptococcus neoformans
Authors: Sun Donglei , Zhang Mingshun , Shi Meiqing 
Published: January 2023

Abstract
Cryptococcus neoformans is a pathogenic encapsulated fungus and a leading cause of fatal meningitis in immunocompromised individuals. IL-27 is a recently identified cytokine affecting both innate and adaptive immunity. Both proinflammatory and inhibitory functions on T cells by IL-27 have been reported in different disease models. Nevertheless, the effect of IL-27 during Cryptococcus infection has never been studied. In current study, IL-27 receptor alpha knockout mice (IL27R KO) was infected with a high virulent cryptococcal strain. We found that mice deficient in IL-27 signaling have significantly increased fungal burden in the lung and shortened survival time. Surprisingly, infected IL-27R KO mice showed unchanged Th1 and Th17 cytokines but significantly reduced Th2 cytokines including IL-4, IL-5 and IL-13. The reduced Th2 response is unlikely to be a cause of increase fungal burden since Th2 was generally known as detrimental during Cryptococcus infection. We next studied the immune cell composition by flow cytometry, no difference in cell number was found for all cell types except neutrophil which is increased during infection indicating more inflammation. The increase of neutrophils is associated with increased chemokines KC and MIP-2. Cryptococcus infection causes sustained production of TNF alpha, we next found that IL-27 suppressed the chemokine release by immune cells as a response to TNF-alpha. Lastly, depletion of neutrophils improved the outcome in infected IL-27R KO mice proving that immune pathology mediated by neutrophils can be detrimental during Cryptococcus infection.
Interaction of both SH2 domains of SHP-2 with a PD-1 homodimer is required for PD-1- mediated inhibition of T cell responses
Authors: Patsoukis Nikolaos , Council Asia , Berg Anders , Bardhan Kankana , Weaver Jessica , Mahoney Kathleen M , Freeman Gordon J. , Boussiotis Vassiliki A 
Published: January 2023

Abstract
PD-1 is a checkpoint receptor, which promotes peripheral tolerance and restrains anti-viral and anti-tumor immunity. PD-1 blockade promotes anti-tumor responses by eliminating PD-1 mediated inhibitory signaling. PD-1-mediated inhibition relies on the interaction of its ITSM motif with SHP-2 but the mechanism is unknown. We examined how PD-1:SHP-2 interaction inhibits T-cell responses. Pull-down assays revealed that PD-1 interacted with GST-SHP-2 fusion protein after PD-1 ligation with simultaneous TCR/CD3-mediated activation and this interaction was mediated via the SH2 domains of SHP-2. SHP-2 contains two SH2 domains (N-SH2 and C-SH2). To determine which SH2 domain is important for PD-1 interaction, we mutagenized the functional sites of N-SH2 and C-SH2. We transfected COS cells with cDNA of SHP-2 wild type or each SH2 mutant together with PD-1 and TCR proximal kinase Fyn, which is required for phosphorylation of PD-1 ITSM. Immunoprecipitation experiments showed that mutagenesis of either SH2 domain abrogated PD-1:SHP-2 interaction, indicating that both SH2 domains are required for interaction with PD-1. We confirmed this finding by Biacore studies. These results indicate that SHP-2 brings together two ITSM-phosphorylated PD-1 molecules by interaction with N-SH2 and C-SH2 domains. Culture of human T cells in the presence of a soluble dimeric PD-L1 inhibited T cell proliferation and IFN-γ production whereas monomeric PD-L1 had the opposite effect. Our results reveal a new mechanism of PD-1:SHP-2 interaction with implications for the development of PD-1-binding compounds to selectively suppress T cell responses by dimerizing PD-1 or to enhance T cell activation by disrupting PD-1 homodimerization.
Intratumoral IL-12 gene electrotransfer-mediated regression of established B16F10 melanoma protects against rechallenge
Authors: Shi Guilan , Edelblute Chelsea , Lundberg Cathryn , Heller Richard 
Published: January 2023

Abstract
Melanoma is an aggressive tumor with limited treatment options and poor prognosis. Interleukin-12 (IL-12) is a potent cytokine mediating antitumor activity. However, it has only achieved modest antitumor effects in clinical trials, often accompanied by unacceptable adverse events. We evaluated whether intratumoral delivery of a plasmid encoding IL-12 using gene electrotransfer (GET) to control the dose could induce rejection of an established poorly immunogenic tumor and avoid dose dependent toxicities.
We treated B16F10 murine melanoma 3 times in 1 week by intratumoral injection of pUMVC3mIL-12 plasmid (pmIL-12, 50 μg) followed by GET. The GET protocols were; EP1 (six 300 V/cm, 100 μs pulses with an array of 6 penetrating electrodes), EP2 (ten 600 V/cm, 5ms pulses with non-penetrating caliper electrodes).
Localized delivery of pmIL-12 with GET in the tumor microenvironment, significantly delayed disease development and prolonged disease free survival and induced long term immune memory protecting against rechallenge. The response was associated with a significant reduction in Treg and MDSC infiltration in B16F10 melanoma and increase of Granzyme B. Mice treated with pmIL-12 EP1 that achieved protection against rechallenge were observed to have CD62LlowCD44high memory T cells. Interestingly, pmIL-12 demonstrated stronger anti-tumor effects than pmIL-12 delivered by EP2.
By manipulation of GET parameters the onset, level and duration of IL-12 protein expression can be controlled, resulting in meaningful therapeutic effects without associated IL-12 toxicities. Furthermore, the approach induced systemic antitumor immune activity and memory and therefore might have an impact against other types of metastatic disease.
Autoreactive T cells display altered CD25 expression that changes responses to low dose IL-2 and antigen delivery.
Authors: Iwamura Chie , Benck Charles , Coley William , Liu Yi , Zhao Yongge , Esposito Juan Antonio Quiel , Tarbell Kristin V 
Published: January 2023

Abstract
Dendritic cells (DCs) are important for T cell tolerance induction and treatment of autoimmune diseases such as type 1 diabetes. Chimeric antibodies that deliver self-antigens to DCIR2+ DCs can delay but not completely prevent diabetes development in non-obese diabetic (NOD) mice. These DCIR2 antibodies induce T cell tolerance via antigen-specific deletion and anergy, but do not increase antigen-specific Foxp3+ regulatory T cells (Tregs). Because low dose (LD) IL-2 administration can preferentially expand Tregs, we asked if delivering antigens to tolerogenic DCIR2+ DCs along with IL-2 would boost antigen-specific Tregs and block autoimmunity. But, surprisingly, adding IL-2 did not increase efficacy of DC-targeted antigens to inhibit diabetes. To date, the effect of LD-IL-2 on autoreactive Treg and effector T cells has not been fully elucidated. By using tetramer staining to identify islet-specific CD4+ T cells in NOD mice, we now show the effects of LD-IL-2, with or without specific antigen delivery to DCIR2+ DCs, on both polyclonal and autoreactive effector and regulatory T cells. As expected, LD-IL-2 increased total Tregs, but autoreactive Tregs required addition of antigen and LD-IL-2 to elicit significant expansion. We found that islet-specific Tregs had lower CD25 expression compared to polyclonal Tregs, but islet-specific Foxp3− cells had higher CD25 expression. IL-2 increased activation and expansion of Foxp3− cells, and this effect was more pronounced for autoreactive cells after treatment with IL-2 + islet antigens. Therefore, IL-2, especially when combined with self-antigens, may not be an effective treatment for chronic autoimmunity, and increased Foxp3+ cells may not be a good biomarker for treatment efficacy.
Targeting the VEGF/GD3 immunosuppressive axis in ovarian cancer
Authors: Bollino Dominique , Muthuswamy Ravikumar , Odunsi Kunle , Webb Tonya J 
Published: January 2023

Abstract
Ovarian cancer is the fifth leading cause of cancer deaths among women, thereby accounting for more deaths than any other cancer of the female reproductive system. It is known that ovarian cancer tissue and ascites contain lymphocytic infiltrates, suggesting that immune cells traffic to tumors, but are then inhibited by immunosuppressive molecules within the tumor microenvironment. Moreover, vascular endothelial growth factor (VEGF) expression is inversely correlated with survival in ovarian cancer patients. Since avoiding detection by the host’s immune system is crucial for the growth and metastasis of cancer, we investigated the effects of ovarian cancer-associated VEGF on CD1d-mediated antigen presentation to natural killer T (NKT) cells. Pretreatment of antigen presenting cells with ascites or conditioned medium from OV-CAR-3 and SK-OV-3 ovarian cancer cell lines suppressed CD1d-mediated NKT cell activation. Ovarian cancer-associated ascites and conditioned medium from ovarian cancer cell lines contain high levels of VEGF and the ganglioside GD3. Importantly, inhibiting VEGF production by ovarian cancer cell lines led to a reduction in GD3 expression and restored NKT cell activation. To elucidate the mechanisms by which VEGF induces GD3 shedding by ovarian cancer cells, we are examining signaling through the VEGF-receptor, assessing its impact in vivo using the ID8-VEGF ovarian cancer mouse model, as well as measuring levels in human blood and ascites. Collectively, these studies identify novel mechanisms through which VEGF impairs anti-tumor immune responses and thus have the potential to enhance therapeutic strategies for the treatment of ovarian cancer.
Colon tumorigenesis mediated by Tollip in neutrophils.
Authors: Lee Christina , Zhang Yao , Yuan Ruoxi , Chen Keqiang , Li Liwu 
Published: January 2023

Abstract
Innate neutrophils have ability to confer either pro- or anti-tumor immune responses. However, molecular mechanisms responsible for the cell polarization are not well understood. Here, we aim to identify and characterize the neutrophil phenotypes in chronic colitis (CC) mouse model with use of AOM and DSS. We identify that Toll-interacting-protein (Tollip) may play a key role in modulating the long-term polarization and function of neutrophils as well as pro-tumorigenesis. We observed that Tollip deficient mice had improved clinical score and reduced generation of colon polyps when subjected to prolonged challenges with AOM and DSS. At the cellular level, Tollip deficient mice challenged with AOM-DSS had distinct neutrophil activation profiles as compared to wild type mice, including the differential expression of cell surface co-stimulatory molecules, migratory behaviors, as well as cytokine expression profiles. Adoptive transfer of neutrophils from Tollip deficient mice to wild type mice recapitulated the outcome of Tollip deficient mice. Based on the in vivo and in vitro studies, we conclude that Tollip may play a key role during the polarization of innate neutrophils involved in the modulation of chronic colitic tumor environment. Further studies with regard to the molecular mechanisms may enable a better understanding of neutrophil modulation in colon tumorigenesis.
Ligation of iNKT TCRs as a novel approach to activate iNKT cells for cancer immunotherapy
Authors: Yuan Weiming , Wen Xiangshu , Schaub Robert 
Published: January 2023

Abstract
Invariant natural killer T (iNKT) cells are innate-like T cells with an invariant TCRa chain and are restricted by CD1d. The activation of iNKT cells has demonstrated potent anti-tumor activity. Current anti-tumor clinical trials using the iNKT cell ligand, a-galactosylceramide (a-GalCer) have had limited success. Major limitations of a-GalCer-based therapies include the bioavailability of lipid drugs and potential over-stimulation of iNKT cells and ensued iNKT cell anergy. Therefore alternative approaches for iNKT cell stimulation are needed to optimize iNKT cell-based anti-tumor therapies. We have engineered a murine iNKT TCR-targeting monoclonal antibody (NKT14m) that directly activates iNKT cells. Based on preliminary results that the potency of NKT14m is less than that of a-GalCer, we reasoned that the addition of IL-12 stimulation would be beneficial for iNKT cell activation. Nevertheless, the toxicity of IL-12 has previously restricted its use in clinical trials. We evaluated the anti-tumor function of a non-toxic low dose of IL-12 in combination with NKT14m. Mice were inoculated with B16 melanoma cells and then treated with IL-12, NKT14m or combination of NKT14m and IL-12. We detected a synergistic anti-tumor effect in the combination of NKT14m and IL-12. These findings represent a new paradigm of iNKT cell activation for their anti-tumor function and future translation into human iNKT cells may provide a novel approach to anti-tumor immunotherapy.
NKT cell subsets involved in host defense from pulmonary Streptococcus pneumoniae infection
Authors: Crosby Catherine Marie , Mikulski Zbigniew , Kronenberg Mitchell 
Published: January 2023

Abstract
Invariant natural killer T cells (iNKT) are a population of innate-like T lymphocytes that have crucial roles in protective responses to infectious agents, particularly Streptococcus pneumoniae. Despite their abundance in the lungs, there is limited understanding of how iNKT cells mediate protection there. Prior work from our group has shown that after pulmonary S. pneumoniae infection, iNKT cells are rapidly activated in a CD1d-dependent manner. Further, others have defined iNKT1, 2, and 17 cell subsets, analogous to CD4+ Th1, Th2, and Th17 subsets. In this study we investigated the roles of lung iNKT cell subsets in protection from S. pneumoniae. In naïve C57BL/6 mouse lungs, we found NKT1 and NKT17 cells were the predominant iNKT cell subsets, with most NKT17 cells in the tissue and NKT1 cells in both the tissue and vasculature. We then utilized fluorescent bacteria, flow cytometry, and intravital microscopy to analyze the lungs during pulmonary infection. At 24 hours, the bacteria localized within the tissue, and were taken up primarily by alveolar macrophages and neutrophils. At 14 and 24 hours, a majority of the lung NKT17 cells were producing IL-17, while only a minor percentage of NKT1 cells were producing IFNγ. This correlated with data from Nur77GFP reporter mice that indicate TCR-mediated activation. At 24 hours, approximately 75% of NKT17 but only 30% of NKT1 cells had been TCR-activated; suggesting NKT17 cells may play a dominant role early in infection. Yet, by 24 hours, NKT1 cells expanded to become the major subset in the lungs, proposing they are also relevant for protection. Experiments are underway to determine when and where subsets are first activated, roles of other cytokines, and consequences of removing individual subsets.
Effector CD4 T cells with stem cell-like properties mediate chronic intestinal inflammation
Authors: Harrington Laurie E , Shin Boyoung , Darley-Usmar Victor , Bellis Susan 
Published: January 2023

Abstract
Increased IFNγ production is a hallmark of mucosal CD4 T cells in inflammatory bowel disease (IBD) patients; however, the role of this cell population in intestinal inflammation remains controversial. To elucidate this, viable IFNγ producing and non-producing CD4 T cells were isolated from mice with colitis and examined for the ability to confer disease. Paradoxical to the proinflammatory nature of IFNγ, CD4 T cells producing IFNγ cause attenuated pathology upon transfer, while IFNγ non-producing cells result in severe intestinal inflammation. The pathogenic IFNγ non-producing cells exhibit a “stem cell-like” gene expression pattern, maintaining genes associated with multipotency including Sell, Tcf7, Lef1, Klf2, and Wnt10a. Consistent with the “stem cell-like” gene signature, IFNγ non-producing CD4 T cells show higher cell survival, superior mitochondrial function, as well as functional plasticity. Conversely, IFNγ producing CD4 T cells express terminal differentiation markers, such as Klrg1, Tim3, Zeb2 and Prdm1, and are more susceptible to cell death. These divergent phenotypes correlate with the glycosyltransferase ST6Gal1. IFNγ nonproducing cells maintain higher levels of St6gal1 mRNA during colitis, while IFNγ producing cells downregulate St6gal1 gene expression. Furthermore, when IFNγ nonproducing cells lose ST6Gal1 activity, they become terminally differentiated, more susceptible to apoptosis and less pathogenic compared to IFNγ nonproducing cells with high ST6Gal1 activity. Together, these data indicate that effector CD4 T cells exist in a spectrum of differentiation states during IBD, from stem cell-like to terminally differentiated, which are associated with IFNγ production and ST6Gal1 activity.
Cross-talk between human glial cells and B cells help propagation of CNS-compartmentalized in progressive MS
Authors: Touil Hanane , Li Rui , Moore Craig , Antel Jack P , Bar-Or Amit 
Published: January 2023

Abstract
B cell depleting therapies efficiently decrease new multiple sclerosis (MS) relapses. Previously, we demonstrated that MS patients harbor abnormally higher proportions of pro-inflammatory effector B cells (Beff), producing high IL-6. TNF and GM-CSF levels compared to controls. B cells are fostered within the MS central nervous system (CNS). Persistence of B cells was reported within lesions and meningeal aggregates, which are adjacent to subpial cortical injury, involving neuronal loss and microglia/macrophage activation, and known to be associated with progressive MS. However, how distinct B cells persist and potentially propagate CNS-local inflammation potentially contributing to disease progression (unmet need) remains unsolved. First, we demonstrated that supernatant from astrocytes supported HC and MS B cell survival (including CD27+ B cells), while M2c-polarized human microglia appeared cytotoxic to B cells. Activated astrocytes increased CD86 expression on B cell surface. Similar results are obtained when B cells were exposed to supernatants of M1-polarized microglia. Furthermore, B cells previously exposed to activated astrocytes increased T cell proliferation. In turn, Beff but not Breg supernatants down-regulate IL-10 production by microglia/macrophage, and substantially enhance pro-inflammatory cytokines (IL-12, TNF & IL-6), independent of phenotypic changes of microglia/macrophage. These results indicate a potential bi-directional interaction between disease-relevant human B cell subsets and astrocytes CNS resident microglia and infiltrating myeloid cells, which may influence the propagation of MS-CNS compartmentalized inflammation associated with disease progression.