bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developmental queues dictate IL-15 expression in γδ T cells (115.4)
Authors: Colpitts Sara , Stoklasek Thomas , Lefrançois Leo 
Published: January 2023

Abstract
Interleukin-15 (IL-15) is a homeostatic cytokine largely produced by myeloid cells. Surprisingly, analysis of a recently generated transgenic reporter mouse using emerald GFP expression as a surrogate for IL-15 promoter activity (EmGFP/IL-15) revealed unexpected expression in lymphoid γδ T cells. Similar to myeloid cells, in which EmGFP/IL-15 is developmentally regulated in the bone marrow, we found that EmGFP/IL-15 expression was downregulated as EmGFP/IL-15high thymic progenitors committed to a mature T cell fate. EmGFP/IL-15 was significantly reduced between DN2 and DN3 cells and silenced in DN4 and single positive thymocytes. However, γδ T cells and their precursors (CD25+ pre-γδ T cells) maintained low levels of EmGFP/IL-15, which was similar to DN3 cells. Interestingly, we found that intestinal intraepithelial γδ T cells were EmGFP/IL-15neg while a small subset of γδ T cells located in the peripheral lymph nodes expressed elevated levels of EmGFP/IL-15. These cells had a CD44highCD62LlowCD27lowCCR6+ phenotype, which corresponded to the Vγ2+ subset of IL-17-producing γδ T cells. These findings suggest that EmGFP/IL-15 is regulated concomitantly with the waves of γδ T cell development occurring perinatally and that transcriptional regulation at the IL-15 locus may overlap with that of IL-17-inducing machinery. Current studies aim to determine if the novel production of IL-15 by γδ T cells contributes to the overall homeostasis of IL-15-dependent cells in vivo.
Properties of TNFR2, PDL-1 dependent human CD8+ regulatory cells generated ex-vivo that can be strongly protective in vivo (116.4)
Authors: Horwitz David , Pan Stephanie , Wang Ju Hua , Lan Qin , Zheng Song Guo , Gray John Dixon 
Published: January 2023

Abstract
In addition to CD4+CD25+Foxp3+ Tregs, natural and induced CD8+ Tregs have been described. Here we report our progress in generating human CD8+ Tregs ex-vivo. Naïve CD8+ cells were activated with anti-CD3/28 beads with IL-2 ± TGF-β for 1 to 9 days. As with CD4+ cells, TGF-β markedly enhanced expression of Foxp3. TGF-β also enhanced CD122, CD103, and PD-1, but decreased granzymes, HLA-DR, CD80 and CD86 expression. Sustained Foxp3 expression and suppressive function was IL-2 dependent. Secondarily stimulated CD8+ cells proliferated weakly, and suppressed activation, proliferation and cytokine production by CD4+ cells in vitro. In vivo functional activity was assessed in NOD SCID IL-2R cγ chain-/- mice injected with allogeneic human PBMC. While human CD4+Foxp3+ Tregs doubled survival from GVHD, CD8 Regs, remarkably, quadrupled survival. Only previously activated CD8+ cells had suppressive activity and protection was unrelated to Foxp3 expression. Adding retinoic acid or rapamycin to TGF-β did not improve survival. By contrast, these activated CD8+ cells rapidly expressed TNFR2 and PDL-1 within one day, and at all time points studied only cells expressing these markers had suppressive activity. Suppressive activity in vivo was IL-10 dependent and partially TGF-β dependent. Thus, in agreement with functional CD8regs described in lupus, diabetes and multiple sclerosis, protective CD8 regs can be induced ex-vivo, and the therapeutic potential of TNFR2, PDL-1+ cells should be carefully explored.
Anti-CD52 therapy in experimental autoimmune encephalomyelitis (116.5)
Authors: Turner Mike , Chretien Nathalie , Havari Evis , LaMorte Michael , Roberts Bruce , Kaplan Johanne , Siders William 
Published: January 2023

Abstract
Alemtuzumab is an anti-CD52 humanized monoclonal antibody that alters the circulating lymphocyte pool and is under clinical investigation for relapsing-remitting multiple sclerosis. A recently developed depleting murine CD52 (muCD52)-specific antibody was evaluated in a standard mouse EAE model to expand our understanding of anti-CD52 therapy. C57BL/6 mice were immunized with MOG35-55 peptide to induce EAE, treated with anti-muCD52 antibody, and characterized with respect to development and severity of disease as well as mechanism of action of the antibody. Results from these studies demonstrated a profound impact of anti-muCD52 therapy. Specifically, prophylactic treatment effectively prevented the development of disease while therapeutic intervention inhibited disease progression and reversed existing symptoms. Longitudinal flow cytometric evaluation demonstrated a decrease in the number of MOG35-55 specific CD4+ T cells as determined by IFNγ intracellular cytokine staining. Simultaneous histological evaluation also showed a reduction in the level of lymphocytic infiltrate in the CNS of anti-muCD52 treated animals compared to control animals that received the vehicle. Collectively, these results demonstrated the therapeutic efficacy of anti-muCD52 treatment in association with a reduction in MOG-reactive pathogenic T cells and diminished lymphocyte infiltration in the CNS of mice with EAE.
CD14 deficiency enhances Th2 responses and alternative activation of macrophages in response to schistosome infection or IL-4. (117.10)
Authors: Tundup Smanla , Srivastava Leena , Nagy Tamas , Harn Donald 
Published: January 2023

Abstract
Prior to exposure to helminth antigens or helminth infection, the resting state of antigen presenting cells (APCs) plays a crucial role in their function in driving CD4+ Th2 immune bias. Whether or not APC innate receptors regulate alternative activation of APCs is not well understood. To test this, we injected schistosome eggs, or schistosome infected wild-type (WT) and CD14 -/- mice and examined evolution of Th2-type responses and alternative activation of macrophages. In response to schistosome infection, or exposure to schistosome eggs, CD14 negatively regulates Th2 responses and alternative activation of macrophages (AAMϕ). CD14-/- mice had enhanced production of CD4+ specific IL-4, IL-5 and IL-13 and increased numbers of regulatory T-cells. Livers of schistosome infected CD14-/- mice had elevated levels of AAMϕs, increased granuloma size with increased collagen deposition compared to WT counterparts. Q-PCR analysis showed significantly increased levels of Ym1, Fizz1 and Arg1 in livers of schistosome infected CD14-/- mice compared to WT controls. CD14 -/- mice injected with Lewis X glycoconjugate or IL-4 also showed significant increase in expansion of AAMϕs. Furthermore, in-vitro studies showed that enhanced alternative activation in response to IL-4 was independent of STAT-6 mediated signaling, suggesting that CD14 regulates both glycan and IL-4 induced alternative activation of macrophages through an unknown mechanism/pathway.
Macrophages and neutrophils in necrotic granulomas from cynomolgus macaques and humans localize to distinct microenvironments and express nitric oxide synthase and arginase enzymes. (117.11)
Authors: Mattila Joshua , Ojo Olabisi , Lin Philana , Flynn JoAnne 
Published: January 2023

Abstract
Macrophages are abundant in granulomas, the hallmark lesion of tuberculosis (TB), where they engage in activities critical for mycobacterial control. The assortment of macrophage functions, ranging from being the primary anti-mycobacterial effector cell to the primary mycobacterial host cell, underscores the complexity of macrophages in this system. Despite their importance, the molecular phenotypes and functions of granuloma macrophages in human TB are not well understood. In this study, we examined a variety of macrophage markers in non-human primate and human granulomas to better describe macrophage diversity and spatial organization. We identified three myeloid cell markers, including CD68, CD163, and HAM56, that stained populations of macrophages occupying discrete positions in necrotic granulomas that may be relevant to granuloma function. Neutrophils expressed high levels of calprotectin, a small bacteriostatic protein sometimes associated with macrophages, and also localized to specific positions in necrotic granulomas. In addition to phenotypic markers, we identified cell-specific expression of nitric oxide synthase isoforms (iNOS and eNOS) and arginase isoforms (arg1 and arg2) expression in granulomas by biochemical, molecular and immunohistochemical techniques. Both macrophages and neutrophils were determined to express NOS and arg enzymes, including co-expression, suggesting these enzymes with opposing effects act in concert to maintain mycobacterial control.
Understanding the role of FTT0831c encoded protein of F. tularensis in modulation of macrophage function (117.15)
Authors: Malik Meenakshi , Schiewe Rachel , Mora Vanessa , Atianand Maninjay , Harton Jonathan , Bakshi Chandra Shekhar 
Published: January 2023

Abstract
Francisella tularensis (Ft), a category A select agent, cripples innate immune defenses of the host to create an environment permissive for its growth. The objective of this study was to understand the mechanisms of innate immune evasion by Ft LVS (Type B) and the highly virulent SchuS4 (Type A) strain. We report that proteins encoded by FTL_0325/FTT0831c genes of Ft LVS and SchuS4 strains respectively, are required for intramacrophage survival, virulence and suppression of proinflammatory cytokines. Our in vitro studies showed that over-expression of FTT0831c suppressed the canonical NF-κB pathway by inhibiting nuclear translocation of the p65 protein resulting in blockade of NF-κB-dependent activation of proinflammatory cytokines. Further studies showed that FTL_0325/FTT0831c gene products are also required for suppression of caspase-1 activation and secretion of IL-1β and IL-18. In conclusion, this study establishes FTL_0325/FTT0831c of Francisella as a key virulence factor that functions as immunosuppressant to facilitate bacterial persistence. Suppression of key signaling pathways via FTT0831c by virulent F. tularensis SchuS4 explains one of the mechanisms adopted by this pathogen to down-modulate the host’s innate immune response.
Anti-inflammatory role of IL-10 producing macrophages during early Brucella abortus infection (117.20)
Authors: Xavier Mariana , Winter Maria , Atluri Vidya , Godinez Ivan , Silva Teane , Barton Greg , Santos Renato , Tsolis Renee 
Published: January 2023

Abstract
Chronic bacterial diseases such as Brucellosis may result from the pathogen’s ability to evade the initial immune response. Moreover, since Brucella spp. is known to target phagocytes, we investigated its effects on macrophage (mø) phenotype and induction of anti-inflammatory responses. Brucella did not induce alternative activation of mø in cultured bone marrow-derived mø (BMM) or in splenic CD11b+ cells isolated from mice during early infection. However, upregulation of interleukin 10 (IL-10) in serum, spleen and splenic mø from B. abortus infected mice was observed as early as 3 days post infection. Infection of BMM from MyD88-/-, TLR2-/-, TLR4-/-, TLR2/4-/- and TLR9-/- mice demonstrated that IL-10 induction was MyD88 dependent and was partially dependent on pathogen recognition by TLR2 and TLR4. Functionally, in vitro IL-10-/- BMM infection resulted in significantly higher pro-inflammatory cytokine production and decreased bacterial intracellular survival. In vivo 9 days infection of IL-10-/- mice confirmed a lower ability of B. abortus to survive in absence of IL-10, as well as higher induction of pro-inflammatory cytokines, resulting in increased pathology in liver and spleen of infected mice. Taken together, our results suggest that early IL-10 induction by infected mø contributes to an initial balance between pro-inflammatory and anti-inflammatory cytokines that is beneficial to the pathogen, thereby leading to enhanced bacterial survival and persistent infection.
Rapid induction of lipid mediators is a novel effector function of the inflammasome in vivo (117.24)
Authors: von Moltke Jakob , Moayeri Mahtab , Trinidad Norver , Kintzer Alexander , Wang Samantha , van Rooijen Nico , Krantz Bryan , Leppla Stephen , Gronert Karsten , Vance Russell 
Published: January 2023

Abstract
Detection of microbial products by host inflammasomes is critical for innate immune surveillance, while eicosanoids, signaling lipids that include the prostaglandins and leukotrienes, are rapid triggers of inflammation. Here we report for the first time a link between inflammasome activation and eicosanoid synthesis. Using a novel protein toxin, we show that systemic cytosolic delivery of bacterial flagellin in vivo leads to loss of vascular fluid into the intestine and peritoneal cavity, resulting in rapid (&lt;30 min) death in mice. This unexpected response is dependent on the inflammasome components NAIP5, NLRC4, and CASP1, but interestingly, is independent of the known inflammasome effector functions, namely IL-1β/-18 production and pyroptotic cell death. Instead, inflammasome activation in resident peritoneal macrophages results, within minutes, in the release of prostaglandins and other eicosanoids that induce vascular fluid loss. Mice deficient in cyclooxygenase-1, a critical enzyme in prostaglandin biosynthesis, are resistant to the pathological effects of systemic inflammasome activation. Compared to other macrophage populations, resident peritoneal macrophages are specifically primed for inflammasome-dependent production of eicosanoids by high expression of Cox1 and other eicosanoid biosynthetic enzymes. Thus, our results identify eicosanoid production as a novel cell type-specific effector function of the inflammasome with dramatic physiological consequences in vivo.
CASPASE-1 SIGNALING IS REQUIRED FOR CONTROL OF TRYPANOSOMA CRUZI INFECTION IN VIVO. (117.27)
Authors: Da Silva Grace , Silveira Tatiana , Sesti-Costa Renata , Gutierrez Fredy , Guedes Paulo , Caetano Braulia , Gazzinelli Ricardo , Zamboni Dario , Silva João 
Published: January 2023

Abstract
The Toll-like receptors (TLRs), 2, 4 and 9 are important to immunity against Trypanosoma cruzi, etiologic agent of Chagas disease. A new family of pattern recognition receptors, Nod-like receptors (NLRs) is described, including NLRP3, which associates to ASC forming a complex that active caspase-1, called inflammasome. This complex is required for cleavage of the active forms of the IL-1β and IL-18. Here, we investigated the role of caspase-1 in the immune response against T. cruzi. First we verify if T. cruzi triggers caspase-1 activation in murine bone marrow-derived macrophages (BMMs). We found high caspase-1 activation in BMMs from WT mice, but not from ASC-/- mice. The blockage of potassium efflux, oxygen radicals reactive (ROS) and B catahepsin (activators of caspase-1 via ASC) resulted in inhibition of caspase-1 activation in BMMs from WT mice. To understand the role of caspase-1, WT, caspase-1-/- and ASC-/- mice were infected with Y strain of T.cruzi. Our results showed that ASC-/- and caspase-1-/- mice presented higher mortality, whereas WT are resistant to infection. In addition, caspase-1-/- mice presented higher myocarditis, increased cardiac damages and more parasites in this tissue on day 17 p.i. Together, these results suggest that caspase-1 dependent of ASC is crucial to infection against T. cruzi. These results reveal new mechanisms involved in the innate immunity against this parasite, which could contribute to new approaches in the control of this disease.
γ-Ray-associated XBP-1+ macrophages as an inducer of M2 macrophages (117.3)
Authors: Kogiso Mari , Nakamura Kiwamu , Kita Katsuhiro , Cornforth Michael , Kobayashi Makiko , Suzuki Fujio 
Published: January 2023

Abstract
The susceptibility of mice to infections with opportunistic pathogens is strongly influenced by M2MΦ appeared in association with whole body γ-irradiation. Therefore, in this study, we investigated why M2MΦ were predominantly generated in mice exposed to whole body γ-irradiation. F4/80+ MΦ were isolated from peritoneal exudates of mice 6-24 h after 5 Gy of γ-irradiation. The expressions of XBP-1 in these MΦ preparations were detected by Western Blot. The production and intracellular CCL2 expression by XBP-1+ MΦ were assayed by ELISA and flow cytometry. In some experiments, resident MΦ were cultured with media supplemented with culture fluids of XBP-1+ MΦ (33%, v/v). MΦ with the ability to produce IL-10 and not produce IL-12 were considered as M2MΦ. In the results, XBP-1+ MΦ were demonstrated in peritoneal MΦ preparations isolated from mice irradiated with 5 Gy of γ-rays. CCL2 was detected in culture fluids of XBP-1+ MΦ. Also, intracellular CCL2 was detected in XBP-1+ MΦ by flow cytometry. The conversion of MΦ from resident MΦ to M2MΦ was demonstrated when resident MΦ were cultured with media supplemented with the culture fluids of XBP-1+ MΦ. Resident MΦ did not change to M2MΦ when they were cultured with XBP-1+ MΦ culture fluids previously depleted of CCL2. These results indicate that the MΦ conversion from resident MΦ to M2MΦ is stimulated by CCL2 released from XBP-1+ MΦ that appear in association with whole body γ-irradiation.
Suppression of the NF-κB Pathway by Diesel Exhaust Particles Impairs Human Antimycobacterial Immunity (117.4)
Authors: Schwander Stephan , Sarkar Srijata , Song Youngmia , Sarkar Somak , Kipen Howard , Laumbach Robert , Zhang Junfeng , Ohman-Strickland Pamela , Gardner Carol 
Published: January 2023

Abstract
Chronic exposure to air pollution increases susceptibility to respiratory infections including tuberculosis in humans. We hypothesized that exposure to diesel exhaust particles (DEP), a major component of urban fine particulate matter, suppresses antimycobacterial human immune effector cell functions by modulating TLR-signaling pathways and NF-κB activation. To examine the effects of DEP on M.tb-induced host immunity, PBMC from 20 healthy persons [13 m, 7 f, mean age 33.5 years) were stimulated with DEP and M.tb or PPD (purified protein derivative). We show by TEM studies that both DEP and H37Ra, an avirulent laboratory strain of M.tb, were taken up by the same peripheral CD14+CD3- blood monocytes. M.tb and PPD-induced IFN-γ, TNF-α, IL-1β, and IL-6 production was reduced in a DEP dose-dependent manner. In contrast, the production of anti-inflammatory IL-10 remained unchanged. DEP stimulation prior to M.tb infection altered the expression of mRNAs encoding TLR 3, 4, 5, 7 and 10 and a subset of M.tb-induced host genes including the inhibition of many NF-κB and IRF pathway target genes. We propose that DEP down-regulate M.tb-induced host gene expression via MyD88-dependent (IL6, IL1A, PTGS2) and MyD88-independent (IFNA, IFNB) pathways. Pre-stimulation of PBMC with DEP suppressed the expression of proinflammatory mediators upon M.tb infection inducing a hypo-responsive cellular state. These findings provide possible mechanism by which air pollutants alter antimicrobial immunity.
Slamf1 controls monocyte / macrophage migration in experimental colitis. (117.5)
Authors: van Driel Boaz , Liao Gongxian , Romero Javier , Faubion William , Wang Guoxing , Berger Scott , O'Keeffe Michael , Magelky Erica , Manocha Monika , Azcutia Veronica , de Waal Malefyt Rene , Grisham Matthew , Luscinskas F. , Mizoguchi Emiko , Bhan Atul , Wang Ninghai , Terhorst Cox 
Published: January 2023

Abstract
Signaling lymphocyte activation molecule (Slamf1) is a T cell co-stimulatory molecule and a regulator of cytokine production by macrophages and dendritic cells. Because Slamf1 positively regulates microbicidal mechanisms in macrophages, we evaluate whether Slamf1 would affect enterocolitis. To induce colitis, mouse CD45RBhi CD4+ T cells were transferred into RAG-/- or Slamf1-/- RAG-/- recipient mice. In a second set of experiments, an agonistic αCD40 antibody was administered to the same recipient strains to induce colitis. Whilst the absence of Slamf1 in RAG-/- recipients mitigated colitis, the function of disease-causing effector or regulatory T cells was not affected by the ablation of the receptor. Surprisingly, in Slamf1-/- mice monocyte / macrophage migration into the inflamed tissue was impaired not only in αCD40-induced colitis but also in two other in vivo models of inflammation: thioglycolate induced peritonitis and in an “air pouch” model in response to TNFα. Administering αSlamf1 to RAG-/- mice ameliorated enterocolitis and altered this migration. Slamf1 is a key contributor to the innate immune responses during experimental colitis by affecting the migration of monocytes / macrophages to the sites of inflammation. As αSlamf1 also mitigates the pathogenesis of colitis, SLAMF1 should be a plausible therapeutic target in treating inflammatory bowel diseases.
Kupffer cells regulate the biological response of inflammatory mononuclear phagocytes to biliary obstruction in mice. (117.6)
Authors: Duwaerts Caroline , Gehring Stephan , Van Rooijen Nico , Gregory Stephen 
Published: January 2023

Abstract
Background: Biliary obstruction is a serious complication of liver diseases. Most studies fail to differentiate the contribution of resident hepatic macrophages (Kupffer cells, KC) and inflammatory mononuclear phagocytes (iMNP) that infiltrate the liver subsequent to injury. This study was undertaken to examine the distinct roles and interactions of these mononuclear phagocyte populations in liver injury attending cholestasis. Methods: Female, C57Bl/6 mice were injected with magnetic beads 3 days prior to sham operation or bile duct ligation (BDL) to facilitate subsequent KC isolation. Three days post-surgery, bead-containing KC and iMNP were separated, purified and analyzed. To examine the ability of KC to modulate iMNP activity, iMNP were isolated from intact and KC-depleted livers on day 3 post-surgery and compared. Results: Following BDL, iMNP exhibited increased expression of Ly-6C and elevated production of chemokines/ cytokines compared to KC. In the absence of KC, iMNP exhibited significant decreases in Ly-6C expression and inflammatory chemokine/cytokine production. Conclusions: KC play a key role in regulating the influx and biological response of iMNP to biliary obstruction and cholestasis.
Recovery of the impaired production of alpha-defensins (HNPs) in cultures of burn patient peripheral blood neutrophils treated with glycyrrhizin (GL) (118.12)
Authors: Yoshida Shohei , Lee Jong , Okita Yamato , Kobayashi Makiko , Herndon David , Suzuki Fujio 
Published: January 2023

Abstract
HNPs produced by neutrophils at the bacterial translocation site play an important role on controlling gut bacteria-associated infections. However, these peptides were not produced by burn patient neutrophils. CCL2 released from burn patient neutrophils was shown to be inhibitory on HNP production. In this study, we tried to recover the impaired production of HNPs in cultures of neutrophils isolated from severely burned patients. Neutrophils (1 x 106 cells/ml), isolated from peripheral blood of severely burned patients and healthy donors, were cultured in media supplemented with burn patient sera (10% v/v) and/or various doses of GL (Minophagen Pharmaceutical Co., Ltd., Tokyo, Japan). Culture fluids were harvested 18 hrs after cultivation and assayed for HNPs by ELISA. In the results, a 28 to 37 ng/ml of HNPs was detected in culture media of healthy donor neutrophils, while these peptides were not produced by burn patient neutrophils. However, HNPs were detected in cultures of burn patient neutrophils treated with 10 to 100 μg/ml of GL. HNPs were not produced by healthy donor neutrophils in cultures supplemented with burn patient sera, and CCL2 was detected in these sera. This chemokine was shown to be inhibitory on HNP production by healthy donor neutrophils. CCL2 was not produced by burn patient neutrophils treated with GL. These results indicate that GL improves HNP production by burn patient neutrophils through the control of CCL2 production.