bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glabridin inhibits dendritic cell maturation and function by blocking the activation of NF-κB/Rel and MAPKs (78.27)
Authors: Kang Jong Soon , Kim Jee Youn , Han Sang-Bae , Lee Kiho , Park Song-Kyu , Kim Hwan Mook 
Published: January 2023

Abstract
Glabridin is known to have anti-inflammatory, antimicrobial and cardiovascular protective activities. The objective of this study was to investigate the effect of glabridin on dendritic cell maturation and function and the molecular mechanisms responsible for this effect. Glabridin dose-dependently suppressed lipopolysaccharide (LPS)-induced expression of maturation markers of dendritic cells, such as CD80, CD86 and MHC-class II molecules, without affecting cell viability. The inhibitory effect of glabridin on functional maturation of dendritic cells was confirmed by enhancement of endocytosis decreased by LPS treatment and suppression of LPS-induced IL-12 production and allogeneic T cell stimulation. The production of IFN-γ and IL-4 in allogeneic T cells was also suppressed by glabridin treatment. Further study demonstrated that LPS-induced activation of NF-κB/Rel and MAPKs, which are known to be important for dendritic cell maturation and functional activation. Collectively, these results demonstrate that glabridin inhibits LPS-induced maturation and functional activation of dendritic cells, at least in part, by blocking NF-κB/Rel and MAPK pathway.
Exogenous antigen enters the major histocompatibility complex (MHC) class I pathway via multiple endocytic compartments with distinct molecular and proteolytic requirements (78.31)
Authors: Belizaire Roger , Unanue Emil 
Published: January 2023

Abstract
Peptides derived from exogenous proteins are displayed by MHC class I via a pathway termed cross-presentation. Despite extensive study, the endocytic compartment(s) that mediate cross-presentation are poorly understood. Immunization of mice with hen egg-white lysozyme (HEL) protein cross-primes CD8 T cells recognizing HEL 23-31 presented by Db. Here we used liposome-encapsulated HEL to examine the cross-presentation capacity of specific subcellular compartments. Liposome-encapsulated HEL targeted to early endosomes, but not late endosomes/lysosomes, entered the MHC class I pathway. Cross-presentation of early endosomal HEL liposomes apparently required the transporter associated with antigen processing (TAP). However, additional experiments indicated no requirement for proteasome-dependent processing or nascent Db. To test the possibility that early endosomal HEL liposomes were presented by endosomal Db independently of TAP, we incubated TAP-deficient antigen presenting cells (APCs) with early endosomal HEL liposomes and a peptide to promote Db surface-stabilization and eventual entry into the endosomal pathway. Addition of Db surface-stabilizing peptide rescued cross-presentation of early endosomal HEL liposomes by TAP-deficient APCs, implying that Db mis-localization accounted for the cross-presentation defect observed previously. Cross-presentation of early endosomal HEL liposomes was inhibited when endolysosomal acidification was blocked by chloroquine. Surprisingly, chloroquine treatment facilitated cross-presentation of both late endosomal/lysosomal HEL liposomes and soluble HEL. Altogether, these data indicate that exogenous protein antigen can enter the MHC class I pathway through multiple routes within the APC.
Targeted delivery of Poly(dG) conjugated protein antigens to antigen presenting cells results in efficient cross-priming in vivo (78.32)
Authors: Toussaint Helene , Erdos Geza , Falo, Jr. Louis D. 
Published: January 2023

Abstract
The development of strategies to efficiently and specifically deliver antigen to antigen presenting cells (APCs) in vivo is a major goal of vaccine design. Internalization of antigen by APCs is a crucial step in immune activation and the mechanism of antigen internalization and trafficking can influence localization in antigen processing compartments and the presentation of antigen to CD4+ or CD8+ T cells. We have designed an APC targeting strategy based on simple and direct coupling of Poly(dG) oligo deoxynucleotides to protein antigens. In comparison to soluble OVA, we find that conjugates of Poly(dG) and OVA (OVA-Poly(dG)) are rapidly internalized by DCs and transverse distinct intracellular processing pathways. OVA-Poly(dG) is both presented to OVA-specific CD4+ T cells (OT-II cells) and efficiently cross-presented to OVA-specific CD8+ T cells (OT-I cells) by DCs in vitro. Importantly, immunization of naïve animals by direct injection of OVA-Poly(dG) results in efficient priming of potent antigen specific CTL responses. Our results suggest that Poly(dG) can target antigen to APCs and serve as a potent adjuvant to induce strong CD8+ T cell-mediated immunity against tumors or viruses. Funding provided by NIH.
A simple one-step method for isolating highly purified plasmacytoid dendritic cells from human peripheral blood (78.33)
Authors: Kokaji Andy I , Holland Siobhan , Fairhurst Maureen A , Thomas Terry E , Guilbault Benoit G 
Published: January 2023

Abstract
Plasmacytoid dendritic cells (pDC) and myeloid DC (mDC) are the two major human dendritic cell populations. Each subset comprises only a small fraction of peripheral blood mononuclear cells (PBMC) and current protocols for their isolation are time consuming, involve multiple steps and often require special equipment. We have developed a rapid and efficient method for the isolation of pDCs from normal blood that yields excellent cell purities and recoveries. Briefly, PBMCs are isolated by Ficoll-Paque PLUS density gradient sedimentation and pDCs are isolated using immuno-magnetic, column-free, negative selection (EasySep®). Our EasySep® technology involves specifically labeling unwanted cells with a cocktail of bi-specific tetrameric antibody complexes and dextran-coated magnetic particles. Using a hand-held magnet, unwanted cells can then be easily removed from the unlabeled pDCs. Flow cytometric assessment of EasySep® isolated pDCs (Lin-, HLA-DR+, BDCA-4+) demonstrate purities of 93.8% ± 3.8% with cell recoveries of 65.6% ± 16.2% (n=9). Using our RoboSep® cell separator, the entire separation procedure can be fully automated with equivalent cell purities and recoveries.
A.I.K is supported by an NSERC Industrial R&D Fellowship
A Threonine-based Targeting Signal in the Human CD1d Cytoplasmic Tail Controls its Functional Expression (78.4)
Authors: Liu Jianyun , Daniel Shaji , Brutkiewicz Randy 
Published: January 2023

Abstract
CD1d molecules are MHC class I-like molecules that present lipids to a unique subpopulation of T cells called natural killer T (NKT) cells. The cytoplasmic tail of human CD1d possesses a tyrosine-based endosomal targeting motif (YXXZ). As such, these molecules traffic through the endocytic pathway, where it is believe that they are loaded with the antigenic lipid that stimulates NKT cells. In the current study, it was found that the T322 residue in the human CD1d tail is a major signal controlling transport to the cell surface and thus its functional expression. Phosphorylation of this residue or removal of the entire cytoplasmic tail negates its ability to regulate CD1d trafficking, resulting in lysosomal targeting and degradation. These results demonstrate an important role of a heretofore unknown signal in the cytoplasmic tail of CD1d that may have relevance to other type I integral membrane proteins that traverse through the endocytic pathway.
RSV-induced expression of TSLP and asthma development (79.13)
Authors: Headley Mark B , Lee Hai-Chon , Ziegler Steven F. 
Published: January 2023

Abstract
Early infection with Respiratory Syncytial Virus (RSV) has long been recognized to predispose certain individuals towards the development of asthma. The immune response to RSV is unique in that it consists of protective Th1 and immunopathologic Th2-type features. Though much is known about the pathology of this disease it is still unclear how RSV infection leads to asthma development. Thymic Stromal Lymphopoietin (TSLP) is a cytokine that has been shown to be both necessary and sufficient for the development of asthma. Mice that express a lung-specific TSLP transgene (SPC-TSLP) develop a spontaneous and progressive asthma-like disease while TSLPRKO mice are highly resistant to disease in an antigen-specific asthma model. In this study we highlight a possible role for TSLP as the link between RSV infection and asthma development. We demonstrate that TSLP overexpression results in sensitization and the development of allergy to environmental antigens. Further, we show for the first time that RSV and its relative, Sendai Virus, lead to increases in TSLP expression by airway epithelial cells both in vitro and in vivo. Taken together these data suggest that TSLP induced by RSV during primary infection may increase susceptibility or directly result in asthma development. Additionally, in this study we show that the RIG-I viral recognition pathway represents a novel pathway leading to TSLP expression.
Relationship between protein allergenicity and glycosylation (79.14)
Authors: Kimber Ian , Almond Rachael , Flanagan Brian F , Dearman Rebecca J 
Published: January 2023

Abstract
Human native and recombinant forms of lactoferrin (NLF and RLF) are available with identical amino acid sequences, but different glycosylation patterns. We have characterised the intrinsic ability of these proteins to induce IgG and IgE antibody responses in BALB/c strain mice and the impact of co-administration. BALB/c strain mice were immunised with various concentrations (w/v) of NLF or RLF alone or in combination by intraperitoneal injection on day 0 and 7. Sera (day 14) were analysed for protein specific IgG and IgE by enzyme-linked immunosorbant assay and passive cutaneous anaphylaxis assay, respectively. RLF alone (1 to 5%) induced detectable IgG responses, but little or no IgE (titer of 1 with 5%). In contrast, NLF (1 to 0.05%) induced vigorous IgG and IgE responses. Forty and 200 times more RLF than NLF was required to induce equivalent IgG and IgE responses, respectively. Co-administration of NLF (0.2%) and RLF (1%) resulted in a significant down-regulation of IgE (titer of 1) in comparison with administration of NLF alone (1/16). This effect was allergen specific as RLF was without effect on IgE responses to the irrelevant allergens ovalbumin and peanut lectin. These results suggest RLF impacts on the induction phase to selectively inhibit IgE responses and that differential glycosylation patterns may impact on antigen uptake, processing and/or presentation to skew towards a type 2 response.
RSV Infection Promotes Cell Cycle Arrest Through TGF-beta Autocrine Regulation; A Critical Stage for Enhanced RSV Replication in Lung Epithelial Cells (79.21)
Authors: Gibbs John D , Ornoff Douglas M , Igo Heather A , Imani Farhad 
Published: January 2023

Abstract
Respiratory syncytial virus (RSV) is a common respiratory viral infection in children, which is associated with exacerbations of asthma, likely due to induction of inflammatory cytokines. We recently reported that treatment of primary human epithelial cells (PHBE) with TGF-β enhanced RSV replication and RSV-induced inflammatory cytokines. Here, we report that TGF-β enhancement of RSV replication is mediated by induction of cell cycle arrest. The data were confirmed by using pharmacologic inhibitors of cell cycle progression such as purvalanol and olomoucine, which enhanced RSV replication. Our data also showed that RSV infection alone resulted in cell cycle arrest in G2/M phase in PHBE cells or G0/G1 phase in A549 cells. Interestingly, RT-PCR and ELISA data revealed that RSV infection induced the expression of TGF-β. Blocking of TGF-β signaling with anti-TGF-β antibody or by using a specific receptor kinase inhibitor resulted in rescue of the RSV-induced cell cycle arrest, suggesting an autocrine mechanism. Collectively, our data demonstrate that RSV regulates cell cycle through TGF-β in order to enhance its replication. These findings provide a plausible mechanistic pathway for the association of RSV with the induction and exacerbations of asthma.
Interleukin-5 producing CD34+ hematopoietic progenitor cells in eosinophilic diseases (80.10)
Authors: Sjöstrand Margareta , Bossios Apostolos , Samitas Konstantinos , Malmhäll Carina , Gaga Mina , Lötvall Jan 
Published: January 2023

Abstract
CD34+ hematopoietic progenitor cells increase in nasal tissue during pollen season and CD34+ cells from human peripheral blood and bone marrow stimulated in vitro produce Interleukin-5 (IL-5). Poor information exists however regarding the role of CD34+ cells in eosinophilic disease.
The aim of this study was to examine whether CD34+ cells produce IL-5 in patients with eosinophilia. Two individuals were examined. The firsts was diagnosed with Churgh-Strauss syndrome with severe asthma, vasculitis and blood eosinophilia (1.9 x 109 L). IL-5 producing CD34+ cells in blood were evaluated by flow cytometry (FACS). Secondly bronchial biopsies were obtained from a patient with moderate persistent asthma and blood eosinophilia (0.3 x 109 L). The bronchial biopsies were immunohistochemical (IC) stained for IL-5 and CD34.
FACS analysis of the patient with Churgh-Strauss syndrome demonstrate that 1, 3 % of the lymphocyte population in the peripheral blood were CD34+ cells and 44% of these cells were positive for IL-5. IC staining of the bronchial biopsies showed IL-5 producing cells and sporadic cells that were positive for IL5/CD34.
IL-5/CD34 + progenitor cells exist in patients with different eosinophilic diseases and may be important when migrating into the local tissue acting as allergy effector cells or by autocrine regulation promoting proliferation of eosinophilic progenitor cells.
Funded by the Swedish HLF.
TGF beta Suppresses Mast Cell Function In Vivo and In Vitro (80.12)
Authors: Fernando Josephine , Ryan John 
Published: January 2023

Abstract
Mast cell activation is a critical component of allergic disease, and may be regulated by cytokines present in the microenvironment. We recently described the suppressive effects of TGFb1 on IgE signaling in mouse and human mast cells. We have furthered this study, demonstrating that TGF injection or aerosolization reduces mast cell IgE receptor expression in vivo, and suppresses eosinophil recruitment in a model of airway hyperresponsiveness. We find that TGFb1 inhibits expression of the key signaling molecules Akt, Fyn, and Stat5 employed by the IgE receptor. In contrast, expression or activation of ERK, JNK, GSK, and p38 was unaffected. Our data support the theory that TGFb1 possesses potent mast cell suppressive activities both in vitro and in vivo.
Repeated fungal exposure leads to eosinophilia and airway remodeling in a murine model of allergic asthma (80.13)
Authors: Samarasinghe Amali E. , Hoselton Scott A. , Schuh Jane M. 
Published: January 2023

Abstract
Allergic asthma is characterized by airway hyperresponsiveness, inflammation, bronchial smooth muscle cell and goblet cell hyperplasia, and subepithelial fibrosis. Differences between human and mouse lung anatomy makes the accurate reproduction of these characteristics challenging to mimic in a mouse model. We hypothesized that repeated allergen exposure would enhance changes observed in the lungs of allergic mice, thereby closely mimicking human disease. C57BL/6 mice were sensitized and challenged with Aspergillus fumigatus antigen and live conidia via airborne delivery respectively over the course of five weeks. Changes in lung architecture, inflammation, antibody, and cytokine profiles were analyzed at days 3, 7, and 14 after the first challenge. An additional group of mice were subjected to a second fungal challenge two weeks after the first, and the same analysis was carried out. While a single challenge resulted in a rapid infiltration and egress of neutrophils at day 3, there were no neutrophils recruited after the second challenge, although eosinophils were recruited more rapidly and in higher quantities. The trichrome stains showed a striking increase in subepithelial collagen deposition and smooth muscle mass immediately following the second fungal exposure. An increase in immunoglobulin (Ig)-E, and a decrease in IgG2a were observed following the second challenge. While cytokines interleukin (IL)-4, IL-5, interferon (IFN)-γ and tumor necrosis factor (TNF)-α peaked at day 14 after the first challenge, the second challenge resulted in peak cytokine levels at day 3. Airborne fungal conidia permits a natural exposure to allergen and mimics characteristics of human asthma with increased eosinophilia, subepithelial collagen, smooth muscle mass, IgE, and cytokines. (2P20RR015566)
Antagonistic Signaling by IL-4 and TGFb Regulates Mast Cell Function (80.5)
Authors: Macey Matthew , Ryan John 
Published: January 2023

Abstract
Mast cells, like all cells of the immune system, are regulated by crosstalk from multiple cytokines, which collectively form a signaling network. Cytokine networking is an important concept for understanding how the immune system is controlled. We hypothesized that the initial presence of pro-inflammatory cytokines in the absence of anti-inflammatory cytokines could desensitize mast cells from anti-inflammatory signals, rendering them more likely to be activated in allergic reactions. Conversely, we hypothesized that the initial presence of anti-inflammatory cytokines in the absence of pro-inflammatory cytokines could shield mast cells from activation by pro-inflammatory cytokines in allergic type responses. In this study, we show that IL-4 and TGFβ1 act as an antagonistic pair in controlling the mast cell response. Mast cell pre-culture with IL-4 decreased TGFβR1 and TGFβR2 RNA and protein levels through a STAT6-dependent mechanism. Further, IL-4 diminished TGFβ1 signaling, blocking SMAD2 phosphorylation. IL-4 also blocked TGFβ1-mediated mast cell death and suppressed TGFβ1-mediated mast cell migration. Mast cell pre-culture with TGFβ1 mirrored this antagonistic effect. TGFβ1 pre-culture reduced IL-4R protein levels, suppressed Il-4-mediated Stat6 phosphorylation, and diminished mast cell migration toward IL-4. When both are present simultaneously, TGFβ1 appears to have a dominating inhibitory effect over IL-4 by blocking proliferation in vitro and recruitment in vivo. These data are important in understanding how cytokine networks can impact mast-cell mediated diseases like asthma. Supported by NIH grants 1R01 AI59638 and U19A1077435.
Basophil-specific and post-translational silencing of a major endoplasmic reticulum heat shock protein gp96 (grp94, HSP90b1) for TLR and integrin (80.7)
Authors: Liu Bei , Li Zihai 
Published: January 2023

Abstract
Basophil has been implicated in anti-parasite defense, allergy and in polarizing TH2 response. However, little is known about its biological significance in vivo, due to lack of basic understanding of basophil developmental/functional cues. As an essential chaperone for multiple Toll-like receptors (TLRs) and integrins in the endoplasmic reticulum (ER), gp96 (grp94, HSP90b1) also participates in general protein homeostasis and in the ER unfolded protein response (UPR) to ensure cell survival during stress. No nucleic cells in mammals have been described to be naturally devoid of gp96. By genetically ablating gp96, we report herein that gp96 is dispensable for basophil development in vivo. Moreover, we found that gp96 was post-translationally cleaved in primary basophils leading to accumulation of a N-terminal ~50 kDa fragment of gp96 and up-regulation of several components of the UPR pathway. The alteration of gp96 was unique to basophils and was not observed in any other cell types including mast cells. Furthermore, we found that deletion of C-terminal domain of gp96 resulted in loss of its chaperone function. Our study revealed a remarkable biochemical event of gp96 silencing in basophils, arguing for the potential importance of shutting down gp96 post-translationally in regulating basophil development and function.
Caspase-mediated apoptosis of myeloid dendritic cells during acute simian immunodeficiency virus infection (81.15)
Authors: Wijewardana Viskam , Brown Kevin N , Liu Xiangdong , Barratt-Boyes Simon M 
Published: January 2023

Abstract
Myeloid dendritic cells (mDC) are depleted from the circulation and their loss inversely correlates with plasma viral load in human immunodeficiency virus (HIV) infection indicating a possible role of this phenomenon in disease pathogenesis. However, the exact mechanism of mDC loss has not been identified. To address this question we studied mDC dynamics in acute simian immunodeficiency virus (SIV) infection of rhesus macaques. Blood mDC from animals that progressed to AIDS were significantly depleted by 12 weeks of infection whereas mDC from monkeys that controlled infection were not. mDC isolated from lymph nodes at 14 days post infection were not significantly infected but did have significant levels of apoptosis. mDC from infected lymph nodes had a 4-fold increase in caspase-3 expression compared to pre-infected lymph nodes. In addition, inhibition of caspase-8, a hierarchical enzyme in the caspase cascade involving the extrinsic pathway of apoptosis, decreased caspase-3 expression by mDC. Expression of BCL-2 proteins did not differ significantly between mDC from uninfected and infected animals, whereas CD95 (Fas) was upregulated in mDC from infected monkeys, indicating a potential role for Fas/FasL in apoptosis. Our studies show that caspase-mediated apoptosis likely plays a role in the loss of mDC in pathogenic SIV infection. Further studies are underway to investigate the initiators of this apoptosis.
The evolution of affinity maturation: Germinal center-like cell aggregates in fish (81.16)
Authors: Magor Brad G , Saunders Holly L , Oko Andrea L 
Published: January 2023

Abstract
Compared with mammals, fish and amphibians have a limited antibody affinity maturation response, an outcome attributed to their lacking distinguishable germinal centres. There is evidence of Ig hypermutation and antigen driven selection, and as such we'd anticipate some sort of germinal center (GC)-like structures, perhaps akin to the varied GC-like cell aggregates observed in different human autoimmune disease. To establish whether fish have GC-like cell aggregates we did in situ hybridization and laser capture microscopy coupled with gene expression analyses on spleen sections of BSA immunized channel catfish. AID expressing cells were found predominantly in tight association with so called melano-macrophage centers or clusters (MMCs). Melano-macrophages have previously been noted for their ability to capture and retain whole antigen and thus had been proposed to be functionally analogous to follicular dendritic cells. Though far smaller than mammalian GCs the fish MMCs also contain CD4 expressing cells and a few flanking plasma cells. However TUNEL assays did not reveal the expected numbers of surrounding apoptotic cells. While there are alternative theories as to the function of these cell aggregates we are proposing that they are primitive germinal centers.
Funded by the National Science and Engineering Research Council - Canada