bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative and applied studies of virulence and immuno-escape of an emerging ranavirus pathogen in the amphibian Xenopus model (43.12)
Authors: Chen Guangchun , Li Zhenghui , Cruz Luna Tanya , Ward Brian , Chinchar V. , Robert Jacques 
Published: January 2023

Abstract
Ranaviruses (RV), family Iridoviridae, have become increasingly prevalent pathogens of amphibians around the world, and are possibly involved in the worldwide decline of amphibian populations. Nonetheless, RVs have not yet been studied as intensively as other large DNA viruses. We have established the frog Xenopus as an important experimental model to study viral pathogenicity and host defenses against RVs such as Frog virus 3 (FV3), and evaluate the contribution of immunocompromised animals in the dissemination of the diseases. To evaluate the role of putative viral genes involved in virulence and immune evasion, we are currently developing a method to systematically knockout (KO) putative virulence genes by site-specific integration of a selectable fluorescent marker into the FV3 genome. Susceptible Xenopus larvae will provide an ideal model to evaluate the impact of KOs on in vivo virus load, host mortality and the induction of pro-inflammatory genes. Normal and immunocompromised adult frogs will be used to investigate pathogenicity and ability of KOs to evade adaptive immunity. These studies will help elucidate the interplay between virulence genes and host immune defenses and may reveal original mechanisms of host-pathogen interaction that may be relevant not only to amphibians and other lower vertebrates, but also to humans.
Two-photon imaging kinetic analysis of Bacillus anthracis spore uptake in the respiratory tract. (45.17)
Authors: Quesnel-Hellmann Anne , Fiole Daniel , Mathieu Jacques , Tournier Jean-Nicolas 
Published: January 2023

Abstract
Inhalational anthrax is a life-threatening infectious disease of considerable concern, especially because anthrax is an emerging bioterrorism agent. The exact mechanisms leading to a severe clinical form through the inhalational route are still unclear, particularly how immobile spores are captured in the upper respiratory tract and transported to the lymph nodes in the early steps of infection. To investigate the role of dendritic cells (DCs) in spore uptake and transport, we infected intranasally CX3CR1 +/gfp mice with Alexa 647-labeled spores. Nasal mucosa, nasal-associated lymphoid tissue (NALT), trachea, lungs and the draining lymph nodes explants were analyzed at different time-points after infection by confocal and/or two photon (2P)-microscopy. We demonstrated that DCs present along the respiratory tract are involved in spore uptake. However, differences in the kinetics of spore phagocytosis between the organs were observed. As soon as 2 hours after infection, DCs bearing spores were found in the thoracic lymph nodes whereas no uptake was observed in the NALT. The role of the NALT in inhalational anthrax will be discussed, as well as some results on lung tissue capture in vivo. Our results demonstrate that DCs play a critical role in spore transport rapidly after infection. The rapid kinetics of pathogen transport may contribute to the clinical features of inhalational anthrax.
Development of Epigallocatechin Gallate as an HIV-1 Microbicide Agent: Impact on Dendritic Cell Innate Immune Responses (46.12)
Authors: Nance Christina , D'Souza Melinda , McMaster Sean , McMullen Ashley , Rajut Zak , Tran Daisy , Siwak Edward , Shearer William 
Published: January 2023

Abstract
Langerhans cells (LC) and monocyte-derived dendritic cells (MDDC), the first line of defense against viral infection, initiate innate immune responses via toll-like receptors (TLR). Previously, we showed inhibition of HIV-1-gp120 binding to CD4 on T cells by the green tea catechin, epigallocatechin gallate (EGCG). We present evidence of EGCG inhibition of the mucosal route of HIV-1 without alteration of dendritic cell (DC) innate immune responses. Methods utilized were CD34+ hematopoietic stem cells and CD14+ cells differentiated to LC and MDDC, respectively, isolated from peripheral blood of HIV-1 seronegative donors, flow cytometry of HIV-1-gp120 binding and TLR profiling with RT-PCR, radioisotope assays for antigen (Ag) studies, MTT assay for cytotoxicity, p24 ELISA for HIV-1 infectivity studies and statistical significance by Student’s t test. EGCG significantly inhibited HIV-1 infectivity in LC in a dose-dependent manner; 100%(50uM;p&lt;0.001), 67%(25uM;p&lt;0.01), 45%(10uM;p&lt;0.05). EGCG significantly inhibited HIV-1-gp120 binding to CD4 in a dose-dependent manner on LC by 95%(50uM;p&lt;0.001), 70%(25uM;p&lt;0.01) and 27%(10uM;p&lt;0.05). Similar results on MDDC. Control catechin did not alter HIV-1-gp120 binding nor infectivity. Neither DC function, as measured by Ag uptake/presentation, nor viability was significantly altered by EGCG. The inhibitory effect on HIV-1-gp120 binding and infectivity of mucosal cells by EGCG may be beneficial in the development of an HIV-1 microbicide.
NSG-hu mice generate HIV specific human immune responses after gp96 vaccination (46.14)
Authors: Gonzalez Louis , Strbo Natasa , Podack Eckhard 
Published: January 2023

Abstract
NOD.SCID common gamma chain (NSG) knockout mice have no functional adaptive immune system of their own; they readily accept human CD34+ hematopoietic stem cell xenografts (NSG-hu). Therefore, NSG-hu mice present a model system in which to study human immunology. Previously, we developed a cell based vaccine combining secreted heat shock protein gp96 and HIV gag protein (293-gp96Ig-HIVgag). Here we use NSG-hu mice vaccinated with 293-gp96Ig-HIVgag to study human immunological responses. Flow cytometry analysis of peripheral blood in pre-vaccination (8-9 week old) animals revealed human engraftment (mCD45 vs. hCD45) ranging from 25%-50%. In addition, human CD45+ cells were detected in specific tissues (spleen, PEC, IEL and MLN); CD4+, CD8+ T cells and NK cells were found within secondary murine lymphoid organs. Post vaccination (12-13 week old) human engraftment of peripheral blood was observed ranging from 15%-79%. In an ELISPOT for IFN-γ, PECs from NSG-hu vaccinated with 293-gp96Ig-HIVgag i.p. generated an HIV specific immune response when stimulated with SLYNTVATL peptide, producing an average of 778 spots per 2x105 cells plated whereas mice vaccinated with 293 cells alone generated an average of 88.5 spots per 2x105 cells plated (p&lt;0.05) We conclude that NSG-hu mice are able to establish and maintain stable hematopoiesis from human derived cells CD34+ cells. Furthermore, NSG-hu mice are capable of mounting a human HIV-specific immune response after gp96 vaccination.
Fibronectin feedback loops and their relationship with inflammatory skin diseases (48.11)
Authors: Kimber Ian , Dearman Rebecca , Basketter David , McFadden John 
Published: January 2023

Abstract
There are several forms of the extracellular matrix protein fibronectin (Fn), such as the alternatively spliced embryonic form that bears an Extra Domain A (FnEDA). This molecule is produced by both T helper (Th) 1 cells and hyperproliferating keratinocytes and binds toll-like receptor (TLR) 4 and induces psoriatic keratinocyte (PK) proliferation. We hypothesise that there are discrete FnEDA feedback loops that impact directly or indirectly on the behaviors of various skin cells and thereby influence skin disease processes. TLR4 stimulation leads to cytokine, chemokine and adhesion molecule expression resulting in Th1/Th17 cell recruitment. Production of FnEDA by recruited Th1 cells will lead to an “inflammatory” FnEDA positive feedback loop. Proliferating PK also release FnEDA in an autocrine fashion (“keratinocyte” loop) and hyperproliferative keratin, a potential autoantigen. An autoimmune reaction would lead to Th1/Th17 cell recruitment with further FnEDA production (“autoimmune” loop). In contrast, in atopic dermatitis (AD) IL-4, IL-13 and vasoactive intestinal peptide down regulate TLR4 and Th2 cells do not produce FnEDA. Therefore, the inflammatory FnEDA loop appears to be actively suppressed in AD, allowing for Th2 dominance. Thus, the inflammatory FnEDA loop is central to Th1/Th17 driven skin inflammatory diseases such as allergic contact dermatitis, whereas there is active down-regulation of this loop in AD and all three FnEDA loops feature in psoriasis.
Cervical mucosal CD8 T cells are more predictive of HPV lesion regression than systemic HPV-specific response (48.13)
Authors: Trimble Connie , Clark Rachael , Hanson Nicole , Tassello Jodie , Frosina Denise , Teague Jessica , Jiang Jenny , Barat Nicole , Kos Ferdynand , Thoburn Christopher , Jungbluth Achim 
Published: January 2023

Abstract
Virtually all squamous cervical cancers and their dysplastic precursor lesions (CIN2/3), are caused by infection with human papillomavirus (HPV), most commonly, HPV16. Although 20-25% of HPV16+ CIN2/3 undergo complete regression, HPV16-specific T cell immunity in blood is only marginally detectable, and does not correlate with lesion regression. To better understand immunity within the cervical microenvironment, we studied T cells and the expression of vascular adhesion receptors in normal and dysplastic human cervical mucosa. The majority of CIN2/3 CD8+ T cells had an activated memory phenotype, and nearly all expressed α4β7. Regression was predicted by lesional intraepithelial CD8 T cells, whereas in persistent disease, CD8 T cells were restricted to the lesional subepithelial stroma. Expression of VCAM-1 and MAdCAM-1, two ligands that support the entry of α4β7+ T cells into tissues, correlated with CD8 infiltrates. Our data provide evidence that reduced adhesion receptor expression on CIN2/3 vasculature may restrict the entry of CD8 T cells into dysplastic mucosa, thereby preventing immunologic clearance. Immune therapies for cervical dysplasia should generate CD8 T cells that express α4β7, and include local manipulation to induce vascular expression of adhesion receptors that can support the entry of these cells into lesional epithelium.
Clostridium difficile Toxin B blocks effector T cell proliferation by inhibiting PLD signaling. (49.19)
Authors: Chandrasekaran Uma , Iwashima Makio 
Published: January 2023

Abstract
Balance between effector and regulatory T cell subsets play significant role in regulating immune responses. Alterations in this balance would result in suppressed or hyper-immune responses and could lead to disorders such as autoimmunity or infections. Our previous work showed that Phospholipase D (PLD) signaling is a factor that can affect the balance between regulatory T cells (Tregs) and non-Tregs. Phospholipase D is a phosphodiesterase that catalyzes the conversion of phosphatidyl choline (PC) to phosphatidic acid (PA). The data demonstrated that inhibition of PLD signaling preferentially blocks growth of non-regulatory T-cells while allowing Tregs to proliferate in response to T cell receptor (TCR) stimulation. Various endogenous and external factors could modulate PLD signaling in T cells and thus alter the host immune responses. Toxin B secreted by Clostridium difficile (TcdB) is a well documented factor that blocks PLD signaling. Here, we show that TcdB produced by Clostridium difficile selectively blocks expansion of effector T cells. Like PLD signal inhibition, TcdB caused inhibition of CD25 expression by activated non-Tregs but allowed expression of CD25 expression by Tregs. Thus, TcdB mediated T cell growth inhibition is likely caused by PLD signaling inhibition in host T cells and may enable C.difficile to modify host immune response, facilitating its long term survival that leads to disease conditions like pseudomembranous colitis.
AMPA receptors are present on mouse lymphocytes and AMPA receptor antagonist, GYKI-52466, inhibits lymphocyte proliferation. (50.31)
Authors: Manivannan Sivabalan , Griffin Diane 
Published: January 2023

Abstract
AMPA receptors are glutamate-gated ion channels canonically found on mammalian neurons for excitatory neurotransmission. AMPA receptors are composed of a tetrameric combination of subunits, GluR1-4, in the form of a homo or hetero dimers. The presence of a post-transcriptionally edited GluR2 subunit confers Ca++ impermeability to the ion channel. Because treatment of mice with viral encephalitis with AMPA receptor antagonists inhibits inflammation and protects from fatal paralysis, we studied the presence and function of AMPA receptors on lymphocytes. Using RT-PCR and restriction digest assays of mRNAs obtained from mouse spleen cells, we showed the presence of unedited mRNA for Ca++-permeable GluR2 and for variants with alternative splicing patterns. Using an in vitro CFSE proliferation assay with plate bound anti-CD3/CD28 we showed that the noncompetitive AMPA receptor antagonist, GYKI-52466, suppresses T-cell receptor CD3+ lymphocyte proliferation in a dose dependent manner, with the greatest effect on CD4+ T-cells. Decreased proliferation correlated with decreased production of IL-2. Lymphocytes treated with GYKI-52466 did not show an increase in cell death compared to controls. These studies show that AMPA receptors are present on lymphocytes and participate in the proliferative response to signaling through the T-cell receptor.
Regulation of type-III interferons in airway epithelial cells. (51.13)
Authors: Gallagher Grant , Siegel Rachael , Eskdale Joyce 
Published: January 2023

Abstract
The type-III interferons (IFNs) are the most recently discovered IFN family, comprising three protein ligands: IFN-λ1, IFN-λ2 and IFN-λ3. Their expression is induced by viruses and they share many anti-viral characteristics with the type-I IFNs (IFN-α and IFN-β), but type-III IFNs have an important specific functional niche at the immune-epithelial interface. However, their expression is diminished in bronchial epithelial cells of rhinovirus-infected asthmatic individuals. We set out to understand type-III IFN regulation. Here, we identify critical elements for IFN-λ1 promoter regulation in bronchial epithelial cells and define key activators (c-REL/p65 NF-κB heterodimer and IRF-1) and repressors (p50 NF-κB homodimer, BLIMP-1 and ZEB1). We show that IRF-1 and BLIMP-1 may occupy an overlapping promoter element. Following poly I:C stimulation, IFN-λ1 expression peaks at 3 hours. This is accompanied by loss of repression by p50 NF-κB homodimers at the promoter. Two important activators are recruited to the promoter: the c-REL/p65 NF-κB heterodimer and IRF-1. Post-induction repression is mediated by p50 NF-κB homodimers, ZEB1 and BLIMP-1. We show that ZEB1 does not regulate type-I IFN expression; thus, it is the first specific regulator of the type-III IFNs. This study represents the first characterization of any type-III IFN promoter in its native context and conformation, and can now be applied to understanding pathogenic dysregulation of IFN-λ1.
Role of reactive oxygen species in gender-associated autoimmunity (83.15)
Authors: Gangaplara Arunakumar , Massilamany Chandirasegaran , Waldner Hanspeter , Reddy Jay 
Published: January 2023

Abstract
Gender-bias exists in proteolipid protein (PLP) 139-151-induced experimental autoimmune encephalomyelitis (EAE) in that both male and female SJL mice develop disease but only females show chronic relapses and their underlying mechanisms are unknown. It has been shown that the reactive oxygen species (ROS) play a role in the mediation of autoimmune diseases, but the recent evidence suggests that ROS can suppress autoimmune responses. We hypothesize that T cell-derived ROS are critical to the maintenance of self-tolerance and favor developing resistance to autoimmunity in male mice. To address this hypothesis, we used PLP 139-151-specific T cell receptor (5B6) transgenic (tg) mice and measured ROS production in activated 5B6 T cells by flow cytometry using CM-H2DCFDA as an ROS indicator. Unexpectedly, we found that T cells from female mice produced two fold more ROS when compared to males. We verified these differences by evaluating mRNA expression of oxidative and anti-oxidative defense genes in 5B6 tg T cells and PLP 139-151-specific T cells sorted from immunized wild type (wt) SJL mice by using PLP 139-151 tetramers. TaqMan PCR analysis revealed that interleukin-22 mRNA, a cytokine implicated in ROS metabolism and EAE pathogenesis was increased by three fold in T cells obtained from tg or wt female mice. The data suggests that sex steroids and T cell-derived cytokines have a role in the maintenance of redox homeostasis in autoreactive T cells and T cell tolerance.
Inability of Monoclonal Antibodies to Clear Red Blood Cells during Incompatible Transfusions is not a Property of the Whole Cell (84.19)
Authors: Liepkalns Justine , Cadwell Chantel , Hod Eldad , Spitalnik Steven , Zimring James 
Published: January 2023

Abstract
During an incompatible transfusion (Tx), antibodies (Abs) against some blood group antigens (Ags) will lead to hemolysis while others will allow for continued red blood cell (RBC) circulation despite IgG binding. We tested the nature of RBC clearance using transgenic mice expressing well-defined RBC Ags and monoclonal Abs. Tx of RBCs, expressing human glycophorin A (hGPA), into mice treated with anti-hGPA IgG1 monoclonal Abs led to partial clearance of those RBCs. A population of RBCs persisted and continued to circulate in a 2nd animal also passively immunized against hGPA, indicating that survival was not due to splenic saturation or consumption of the monoclonal Abs. We therefore concluded that these hGPA RBCs were resistant to clearance as they were also positive for hGPA and bound Abs. These studies were also performed using RBCs expressing the Duffy Ag and anti-Duffy IgG2a monoclonal Abs. To test if resistance comprises a whole cell protection from Ab-induced lysis, we transfused blood expressing both hGPA and Duffy Ags into mice passively immunized against hGPA. The resistant RBCs were then transfused into mice passively immunized against Duffy. Although these RBCs were able to resist a 2nd Tx against the same anti-hGPA Ab as the one used during the 1st Tx, these did not resist a 2nd Tx during which anti-Duffy was used. We, therefore, conclude that resistance occurs with different Ags and is not a property of the cell but rather is at the Ag-Ab level.
Isolation and Expansion of Antigen-Specific Mouse T cells using Dynabeads® (85.9)
Authors: Schjetne Karoline , Reed Berit 
Published: January 2023

Abstract
Background: CD134 (OX-40) and CD137 (4-1BB), both members of the TNFR-family, functions as costimulatory molecules promoting proliferation and survival of activated T cells. CD134 and CD137 also identifies recently activated CD8+ and CD4+ T cell and represent a promising approach for the isolation and expansion of viable T cells of a defined specificity. Results: Dynabeads® Mouse CD134 isolates activated antigen-specific T cells by use of an agonistic anti-CD134 antibody conjugated to Dynabeads®. The bead-bound cells are separated on the magnet promoting a prolonged activating signal to the T cells during culture. Dynabeads® Mouse T-Activator CD3/CD28/CD137 enables an easy expansion of the isolated T cells to be used for downstream analysis. Discussion: Dynabeads® Mouse CD134 allows for specific isolation of T cell with defined antigen specificity directly from a crude sample (e.g. splenocytes or tissue from immunized mice) in an easy-to-use in vitro procedure. Its use in combination with Dynabeads® Mouse T-Activator CD3/CD28/CD137 enables easy and reliable isolation and expansion of T cells of a defined specificity. With Dynabeads® Technology, pure, viable T cells can be conveniently isolated for downstream analysis.
Minimum Information About a Genotyping Experiment (MIGen) (88.8)
Authors: Huang Jie , Marthandan Nishanth , Pertsemlidis Alexander , Ding LiangHao , Kozlitina Julia , Maher Joseph , Olsen Nancy , Rios Jonathan , Story Michael , Xing Chao , Scheuermann Richard 
Published: January 2023

Abstract
Genotyping experiments are widely used in clinical and basic research laboratories to identify associations between genes and normal/abnormal phenotypes. Genotyping assay techniques vary from PCR reactions in a test tube with gel electrophoresis detection to high throughput chip or bead array assay employing various technologies for automatic genotype calls. Depending on the study purpose and design, the resulting genotype data could involve millions of markers for thousands of individuals, requiring substantial data analysis using various statistical, modeling or other methodologies. To date, there is no standard for reporting genotyping experiments. Here we present the Minimum Information About a Genotyping Experiment (MIGen) standard. MIGen recommends the standard information required to report a genotyping experiment, covering: study and experiment design, subject information, sample collection and processing, genotyping procedure, and data analysis methods, if applicable. The goal of MIGen is to set a reporting standard for adoption by the research community to facilitate consistent data interpretation and independent validation/reproduction, and to serve as guidance for database design for storing genotyping experiment data. MIGen is being developed as a collaborative project involving international domain experts and is a registered project under MIBBI: Minimum Information for Biological and Biomedical Investigations. Supported by NIH N01AI40076.
ATP and lipoteichoic acid act cooperatively to induce a DC phenotype that promotes Th17 in an IL-23- and IL-1B-dependent manner (89.28)
Authors: Koski Gary , Paustian Christopher , Johnson Terrence 
Published: January 2023

Abstract
We investigated whether pairing TLR ligands with an “endogenous” danger signal, extracellular adenosine triphosphate (ATP), would act in synergy to induce in monocytes unique DC-like properties. The TLR2 ligand lipoteichoic acid (LTA) and ATP were efficient partners for cooperatively enhancing expression of IL-23 and IL-1b when monocytes were cultured in GM-CSF, but not when IL-4 was included. These cells showed DC-like properties including activated DC surface phenotype and enhanced migration towards CCR7 ligands. They also preferentially skewed allogenic CD4pos T lymphocyte responses toward the IL-22hi, IL-17hi/IFN-glo Th17 phenotype, a capacity inhibited by neutralization of either IL-23 or IL-1b, but not IL-6. Although pharmacological activation of either ionotropic or cAMP-dependent pathways acted in together with LTA to enhance IL-23, only inhibition of the cAMP-dependent pathway antagonized enhancement of cytokine production by ATP. In addition, ATP plus atypical lipopolysaccharide from P. gingivalis (signaling through TLR2) was superior to E. coli-derived LPS (TLR4 ligand) for promoting the high IL-23-secreting DC-like phenotype, but considerably inferior for inducing IL-12 p70 production when paired with IFN-g. Collectively, our data suggests TLR2 ligands encountered by innate immune cells in an environment rich in extracellular ATP can induce a distinct activation state that supports an IL-23- and IL-1b-dependent Th17 type response.