bluuebunny/crossref_metadata_2025_split huggingface dataset:
Suppression of the Immune Response to Human FVIII with FVIII Transgene Modified Tolerogenic Dendritic Cells in Hemophilia A Mice (89.42)
Authors: Su Rui-Jun , Epp Angela , Wu Xiaoping , Josephson Neil 
Published: January 2023

Abstract
The development of inhibitory antibodies to factor VIII (FVIII) is the most serious complication in hemophilia A patients. In this study we evaluated the ability of tDCs transduced with a human FVIII transgene foamy virus (FV) vector to modulate the immune response to FVIII in hemophilia A mice. The tDCs were generated by culturing bone marrow cells in RPMI1640/10%FBS supplemented with IL-10 and the neural peptides VIP and PACAP38. Na ?ve hemophilia A mice were treated with 2 weekly infusions of tDC-F8, control tDCs (tDCs-Ctrl), or with no cells (Neg-Ctrl) prior to challenge with four weekly intravenous doses of 0.2 µg rhFVIII. Following immunization the inhibitor titers in tDC-F8 mice were 60-61% lower than the controls. The regulatory T cell related markers such as FOXP3 were up-regulated on splenic CD4+ T cells from tDC-F8 mice and the CD4+ T cell proliferation response to FVIII was suppressed by 80 - 90%. In pre-immunized mice, treatment with 4 weekly infusions of FVIII vector transduced tDCs lowered inhibitor titers by 54%. In contrast, treatment with untransduced tDCs had no significant effect. Adoptive transfer of CD4+ T cells from tDC-F8 mice suppressed the immune response to FVIII in subsequently immunized naïve secondary recipients, but not to OVA, an unrelated antigen. We also observed that infusion of tDCs transduced with FV vectors co-expressing FVIII and IL-10 into naïve mice resulted in a 83 - 85% reduction in inhibitor titers after subsequent immunization. The CD4+ T cell proliferation response to FVIII was suppressed over 90%. In summary, these data indicate that FVIII vector transduced tDCs are useful in suppressing the immune response to FVIII in hemophilia A mice and that co- expression of IL-10 by the vector modified tDCs further enhances their effectiveness.
The neuropeptide npT1 is specifically expressed in human CD25+ regulatory T cells (89.5)
Authors: Prots Iryna , Skapenko Alla , Lipsky Peter E. , Schulze-Koops Hendrik 
Published: January 2023

Abstract
The mechanisms that regulate the generation of peripheral Tregs are largely unknown. To gain insights into Treg differentiation on a molecular level, we performed gene expression profiling at different stages of peripheral Treg development. Peripheral Tregs were generated from human naive CD4+CD25- T cells in the presence of interleukin (IL)-4. Gene expression of CD25+ Treg cells was assessed at days 3, 5, 7, and 10 of culture by microarrays and was compared to that of CD25- T cells and of CD25+ effector T cells generated in the absence of IL-4. At early stages of Treg development, the majority of identified genes were involved in cell cycle control, whereas at later time points, Treg-specific genes predominantly encoded for transcription factors and signal transduction molecules. Of interest, the neuropeptide, npT1 was strongly upregulated during late Treg development and was virtually absent in CD25- T cells. Upregulation of npT1 in CD25+ effector T cells was below 5% compared to CD25+ Tregs. Expression of npT1 in in vitro generated Tregs was confirmed by RT-PCR in independent experiments. Of note, npT1 was also expressed by resting and activated natural occurring CD25+ Tregs purified from the peripheral blood of healthy donors. Thus, npT1 is a novel Treg specific protein that is expressed in late developing and functionally mature peripheral and natural occurring Tregs.
Antigen-specific tolerance to the fetus in murine pregnancy (89.9)
Authors: Perchellet Antoine , Petroff Margaret 
Published: January 2023

Abstract
Tolerance of the maternal immune system is believed to be important for successful pregnancy as the fetus is semi-allogeneic. We examined maternal T cell tolerance in mice using a system in which a model antigen, ovalbumin (OVA), is expressed exclusively in the fetus. This is achieved by breeding females that lack OVA to male mice that transgenically express membrane-bound OVA under the control of the β-actin promoter. By employing T cell receptor (TCR) transgenic mice specific for a MHC class II-restricted epitope of OVA (OT-II) as mothers, we investigated the fate of fetus-specific CD4+ T cells during gestation. OVA-specific CD4+ T cells displayed an activated phenotype in the spleen and lymph nodes of OVA-bred OT-II mice, consistent with their encounter of fetal antigen in peripheral lymphoid tissues. A small percentage of OVA-specific CD4+ T cells were deleted in the periphery of OVA-bred OT-II mice, with evidence of TCR downregulation in a portion of the remaining T cells. Interestingly, deletion and TCR downregulation were also observed in the thymus of OVA-bred OT-II mice, suggesting that fetal antigen may affect central tolerance. These preliminary data indicate that fetal antigen-specific maternal CD4+ T cells are tolerized during gestation. This project is supported by NIH grants HD045611 and HD049480, and a Lied Endowed Basic Science Pilot grant. A. Perchellet is supported by NIH training grant T32HD007455.
Plasmacytoid dendritic cells are crucial for Th17 differentiation (90.14)
Authors: Ishifune Chieko , Maekawa Yoichi , Yoshimoto Takayuki , Yasutomo Koji 
Published: January 2023

Abstract
Plasmacytoid DCs (pDCs) produces type I interferon by CpG stimuli, and controls both innate and adaptive immune responses. However, it is largely unknown that pDCs are involved in Th17 differentiation together with controlling other types of helper T cell functions. Therefore, we here examined if pDCs control Th17 differentiation.
To investigate T cell differentiation ability of pDCs, CpG-activated BM-derived pDCs (CD11c+mPDCA-1+B220+) were co-cultured with CD4+ T cells in the presence of anti-CD3 mAb. We found that pDCs have stronger ability to induce Th17 than conventional DCs (cDCs)(CD11c+mPDCA-1-B220-). We also observed stronger Th17 inducing ability of pDCs than cDCs even when OT-II T cells were stimulated by pDCs or cDCs cultured with OVA protein. Th17 differentiation by pDCs was inhibited by addition of IL-6 neutralizing antibody and pDCs could not induce Th17 from STAT3 deficient T cells. Furthermore, CpG-activated BM-derived pDCs could produce more Th17-related cytokines than cDCs. Experimental autoimmune encephalomyelitis (EAE) is a Th17-mediated disease. To investigate if pDCs are involved in progressing EAE, pDCs were depleted by mPDCA-1 mAb in EAE mice. The clinical score of EAE and the production of IL-17 from CNS-infiltrated lymphocyte were much lower in pDCs-depleted mice than control Ig-treated mice. Taken together, those results suggest that pDCs are crucial DCs subset for the differentiation of Th17.
Interleukin-27: A Modulator of Th1 Differentiation in human newborns (90.18)
Authors: Doganci Aysefa , Zepp Fred , Meyer Claudius U 
Published: January 2023

Abstract
Objective: The initial description of IL-27 indicated that it plays a role in the early regulation of T helper type 1 (Th1) initiation, induces proliferation of naïve CD4 T cells and synergizes with IL-12 in IFN-γ production. Furthermore it has broad inhibitory effects on Th2 and Th17 subsets of T cells as well as the expansion of inducible regulatory T cells. As an IL-12-related cytokine IL-27 is frequently present at sites of inflammation that can promote both anti- and pro-inflammatory immune responses. To highlight the effects of IL-27 in the specific context of the neonatal immune response, we compared its role in CD4+ T cells in both human cord and adult blood.
Methodology/Principal Findings: Umbilical cord blood samples were collected from healthy full-term infants born by cesarean sections. Leukocytes from adults were enriched from leucapheresis products. After density centrifugation, the mononuclear cell fraction (PBMC) was washed and cells were magnetically labelled for CD4+ T cells and enriched in a magnetic field, following stimulation with IL-27 for ascertainment of T cell response in vitro.
Our data indicate that addition of IL-27 induced the production of IFNγ (n= 9-11; p=0,047) in neonatal CD4+ T cells, whereby IL-17 is decreased considerably. Furthermore we noticed enhanced phosphorylation of Stat-1 (n=6-9; p=0,008) in cord blood compared to adult blood. These data suggest that binding of IL-27 to its receptor initiates Th1 responses in naïve T cells of human newborns.
Conclusions/Significance: Taken together, our results suggest that IL-27 compensate the restricted Th1 immune response in human newborns to a higher extend as compared to adult T cells.
Notch ligands jagged-1 and delta-like 4 differentially regulate effector and memory CD4+ T cell expansion during Th2 inflammation (90.21)
Authors: Schaller Matthew A , Coelho Ana Lucia , Lindell Dennis M , Lincoln Pamela , Carson William F , Ito Toshihiro , Cavassani Karen A , Chensue Stephen W , Hogaboam Cory M , Lukacs Nicholas W , Kunkel Steven L 
Published: January 2023

Abstract
Notch ligand jagged-1 is constitutively expressed on dendritic cells, whereas Notch ligand delta-4 is induced by TLRs. It has been hypothesized that jagged-1 is important for directing Th2 responses, while delta-4 plays a role in suppressing Th2 cytokines. To determine the role of jagged-1 in Th2 responses, we administered anti jagged-1 antibody to mice during the formation of S. Mansoni induced lung granulomas in sensitized mice. Our results showed a higher amount of IL-4 in lymph nodes and an increase in the CD4 effector cell population (CD44hi CD62lo). To determine if this increase in effector cells arose from an increase in effector or memory cell proliferation, we transferred either memory (CD44hiCD62L+CCR7+) or effector cells into congenic S. Mansoni sensitized mice, induced granuloma formation, and administered anti jagged-1 antibody. Our results indicate that effector cell expansion is significantly reduced in the absence of jagged-1, and central memory cell expansion is increased under the same conditions. This occurred in an antigen specific manner and was true regardless of if the inflammation was Th1 or Th2 in nature. Additional experiments revealed that delta-4 had the opposite effect as jagged-1. A blockade of delta-4 during Th2 inflammation caused an increase in effector cell proliferation, thus defining opposing roles for these two molecules in directing memory and effector cell expansion.
Funding provided by NIH: N0105330-397736
Nitric oxide regulates TLR sensitivity and cytokine production by PDCA1+/Ly6C+ “inflammatory” dendritic cells and dendritic cell programming of Th1 immune responses. (90.28)
Authors: Giordano Daniela , Li Chang , Clark Edward E 
Published: January 2023

Abstract
Studies using Nitric Oxide Synthase 2 knockout (NOS2 KO) mice have implicated nitric oxide (NO) in the control of Th1 T cells, autoreactive T cell and prevention of autoimmunity. We investigated whether the effect of NO on DCs might contribute to the NO-mediated control of Th1 immune responses. We found that GM-CSF and IL4-derived bone marrow DCs (GM/IL4-DCs) from NOS2 KO mice have enhanced survival and responsiveness to TLR signals compared to WT DCs. TLR stimuli induce a substantial up-regulation in NOS2 KO GM/IL4-DCs of a Ly6Ch DC subset characterized by: 1) high expression of co-stimulatory molecules and other maturation markers (CD86h/MHCIIh/PDCA1+); 2) a substantial increase in inflammatory cytokine production; and 3) decreased Mac3 expression compared to WT DCs. The DC subset dysregulated in the absence of NO resembles the recently described "inflammatory" DC. Furthermore, TLR-stimulated OVA-loaded, NOS2 KO GM/IL4-DCs compared to WT DCs induced increased IFNγ production of OTII CD4+ T cells either in vitro or in vivo. Our findings suggest that autocrine NO drives DC differentiation toward an "inflammatory" DC with a more macrophage phenotype and with lower co-stimulator/antigen-presenting capability and cytokine production, and thus toward a DC with less potential to activate Th1 immune responses. The [EC1]NO effects on DC programming of T cells may be crucial for the protective role of NO in autoimmune diseases. (Supported by NIH grants AI44257 and AI52203).
[EC1]less potential for adaptive immunity, why would this be a good thing?
Dissection of the reciprocal interaction between T helper cells and B cells during an immune response in vivo (90.4)
Authors: Baumjohann Dirk , Lanzavecchia Antonio , Sallusto Federica 
Published: January 2023

Abstract
Cognate interaction of B cells with antigen-specific T helper cells in secondary lymphoid organs is required for production of high-affinity antibodies and for generation of memory B cells and long-lived plasma cells. To gain insight into the nature of signals regulating these different aspects of B cell responses, we set up an experimental system in which CD3ε-/- mice - which lack T cells but have normal B cell development - are reconstituted with small numbers of TCR-transgenic T cells. Serum antibody levels, germinal center reaction, as well as generation of antibody-secreting cells and long-lived plasma cells were monitored at different time points after primary and secondary immunization. We found that adoptively transferred antigen-specific CD4+ T cells induced effective primary antibody responses; however, serum antibody levels were not sustained. Further analysis revealed that upon immunization T cells proliferated extensively but became exhausted, did not respond to secondary antigenic stimulation, and also failed to provide B cell help upon booster immunization. Although immunoglobulin class switch recombination, initiation of germinal center reaction, and differentiation of B cells to antibody-secreting short-lived plasma blasts were comparable in reconstituted CD3ε-/- mice, affinity-maturation was impaired and long-lived plasma cells were not generated or did not migrate to the bone marrow. Data will be presented on the mechanistic link between B cell-T cell interaction and the exhausted state of T helper cells in our experimental system. The results of the study suggest the existence of distinct early and late T cell-dependent events in initiation and maintenance of humoral immune responses.
This work was supported by a Boehringer Ingelheim Fonds PhD Scholarship to D.B.
Jak2 deficiency prevents mice from LPS-induced sepsis by modulating innate immunity without affecting adaptive immunity through STAT5 and STAT6 pathways (91.17)
Authors: Zhong Jixin 
Published: January 2023

Abstract
Dendritic cells (DCs) serve as a key component of innate immunity and bridge innate and adaptive immune responses against to bacteria and other pathogens. Many immune disorders are thought to be a consequence of out-of-control of inflammatory response to bacterial toxins, such as sepsis is a result of excessive inflammation with a suppression of adaptive immunity post-sepsis. Therefore, manipulating the function of DC in innate immune response without affecting its capability to initiate adaptive immunity could be a novel therapeutic approach for treatment of sepsis. Using an inducible Jak2 deficiency model, here we have demonstrated that Jak2 could be a perfect target to solely suppress DC's capacity in innate immune response. Other than its functionality in DC development, Jak2 also plays a pivotal role in modulation of innate immune response. DCs deficient for Jak2 display an immature phenotype characterized by low expression of MHC-II and costimulatory molecules and a reduced secretion of pro-inflammatory cytokines upon stimulation. However, their capability to initiate adaptive immune response was not impaired. As a result, mice deficient for Jak2 are resistant to LPS-induced septic shock. Our studies further revealed that Jak2/SATA5 signaling is implicated in DC development, while Jak2/STAT6 signaling is responsible for the regulation of pro-inflammatory cytokine secretion in DCs.
MyD88-dependent Inhibition of TLR4/TRIF Associated Signaling after Monophosphoryl Lipid A Stimulation (91.20)
Authors: Cekic Caglar , Casella Carolyn R. , Mitchell Thomas C. 
Published: January 2023

Abstract
TLR4 stimulation leads to the activation of both MAL/MyD88 and TRAM/TRIF pathways. Recently we identified synthetic monophosphoryl Lipid A (sMLA) as a Trif-biased agonist of TLR4. However, not all TRIF dependent genes were induced optimally after sMLA stimulation. In this study we show that there is a MyD88-dependent inhibition of IFNβ expression after sMLA but not after synthetic diphosphoryl Lipid A (sDLA) stimulation in monocytic dendritic cells (DCs). The IFNβ promoter has binding sites for NF-κB, AP-1 and IRF3, transcription factors activated by IKKα/β, MAPKs (JNK, p38 and ERK) and TBK1, respectively. Functional studies with specific inhibitors showed that JNK and p38 but not ERK1/2 played a major role in IFNβ expression both in MyD88KO and Wild type (WT) DCs. However, phospho-activation of these MAPKs as well as of IKKα/β were decreased in MyD88KO vs. WT DCs after sMLA or sDLA stimulation. However, sMLA but not sDLA induced stronger IRF3 phospho-activation in MyD88KO cells when compared to WT suggesting a MyD88 dependent regulation of TBK1 activation. Preliminary studies indicate differential kinetics in MyD88 recruitment after sMLA stimulation, which may be responsible for this inhibitory effect via an unknown mechanism. These findings identify a novel role for MyD88 in regulation of IFNβ expression based on ligand structure.
This work was supported by the NIH/NIAID and the AHA.
SHIP deficient macrophages promote inflammation by supporting the generation of Th17 cells (91.5)
Authors: Tarasenko Tatiana N , Bolland Silvia 
Published: January 2023

Abstract
SHIP is an SH2-containing inositol phosphatase expressed in all hematopoietic cells and proposed as negative regulator of the immune response. SHIP-null mice show increased mortality due to a myeloproliferative-like syndrome. To better understand the function of SHIP we used a conditional disruption of SHIP in the macrophage-monocyte lineage (LysMcreSHIPfl/fl), which partially recapitulates the myeloproliferative phenotype of the null deletion. Macrophages from LysMcre SHIPfl/fl mice display an M2 phenotype likely due to enhanced signaling through the GM-CSF receptor. Deletion of SHIP in macrophages not only leads to myeloid hyperproliferation, but also to lymphocyte activation as a secondary effect. LysMcreSHIPfl/fl conditional mice develop splenomegaly with a large number of activated lymphocytes. We determined that T cells in these mice are biased towards the Th17 phenotype and expand the regulatory population. LysMcreSHIPfl/fl mice show higher mortality and greater induction of Th17 cells in the autoimmune model of EAE. Taken together, we have uncovered a specific regulatory role of SHIP signaling in macrophages that has important consequences in negatively regulating macrophage function directly and T cell development indirectly.
Targeting the Activated Macrophage with Folate-Conjugated Compounds in Experimental Atherosclerosis (92.11)
Authors: Ayala-López Wilfredo , Xia Wei , Henne Walter A , Low Philip S 
Published: January 2023

Abstract
Macrophages are central to the development of atherosclerosis. Folate-receptor positive (FR+) macrophages have been reported to orchestrate inflammatory processes in multiple inflammatory diseases, but the role of FR+ macrophages in atherosclerosis is unknown. Here, we report the use of folate to target radioactive and fluorescent imaging agents to macrophages present within aortas of atherosclerotic ApoE-/- mice. Folate-targeted 99m-Tc and folate-DyLight680 were synthesized and injected into ApoE-/- mice that were fed either normal or Western chow for 25 weeks. Mice and their excised aortas were then imaged to assess accumulation of both folate conjugates. Flow cytometric analysis of single cell suspensions of collagenase-digested aortas was also performed. Folate-targeted compounds, but not nontargeted compounds, were found to accumulate in atherosclerotic lesions of ApoE-/- mice, with greater uptake in mice fed Western chow than normal chow. The targeted cells were also confirmed to be FR+ macrophages. These data demonstrate that FR+ macrophages are present in atherosclerotic lesions and that they can be targeted with folate-conjugated compounds. Folate targeting could conceivably be developed for the staging of atherogenesis and treating of the associated disease.
TNF-related apoptosis-inducing ligand (TRAIL) induces osteoclast differentiation from monocyte/macrophage lineage precursor cells via TRAF-6 dependent pathway (92.14)
Authors: Hsu Ping-Ning , Huang Shih-Chia 
Published: January 2023

Abstract
Human osteoclast formation from mononuclear phagocyte precursors involves interactions between tumor necrosis factor (TNF) ligand superfamily members and their receptors. Many of the proinflammatory cytokines and growth factors implicated in inflammatory processes have also been demonstrated to impact osteoclast differentiation and function. Recent evidence indicates that the TNF-related apoptosis-inducing ligand (TRAIL) of the TNF ligand superfamily, which was initially thought to induce apoptosis in many transformed cell lines, can serve as an effector molecule in activated T cells. We show in this work that TRAIL can induce osteoclast formation from human monocytes and murine RAW264.7 macrophages. We demonstrated that both cell models differentiate into osteoclast-like cells in the presence of TRAIL in a dose-dependent manner, as evaluated in terms of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells and bone resorption activity. The TRAIL-induced osteoclast differentiation is independent of caspase activation and apoptosis induction activity. However, TRAIL-induced osteoclastogenesis is dependent on activation of NF-£eB, ERK, and p38 MAP kinase. The TRAIL-induced osteoclastogenesis was significantly inhibited by treatment with TRAF-6 siRNA and TRAF-6 decoy peptide, indicating this pathway is TRAF-6 dependent. Thus, our data demonstrate that TRAIL induces osteoclast differentiation via direct engagement with the TRAIL death receptor through a signaling pathway distinct from apoptosis. Our results indicate that in addition to triggering apoptosis, TRAIL induces osteoclast differentiation. It provides a novel role for TRAIL in regulating osteoclast differentiation and in osteoimmunology.