bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tart cherry extract improves skeletal muscle recovery by increasing type II MHC expression, MCP-1 and HGF secretion, and attenuating ROS production by neutrophils
Authors: Pelletier Margery G.H. , Szymczak Klaudia , Barbeau Anna M. , Bishop Erin J. , Johnson Benjamin B. , Lee Andrew J. , O’Fallon Kevin S. , Gaines Peter 
Published: January 2023

Abstract
Ingestion of tart cherry extract (TCE), a rich source of polyphenolic anti-oxidant/anti-inflammatory compounds, improves skeletal muscle (SM) recovery following exercise-induced muscle damage. This response may be due in part to attenuated oxidative/pro-inflammatory activities of recruited neutrophils and macrophages during SM regeneration. How TCE promotes the molecular mechanisms regulating SM regeneration or attenuates those controlling myeloid cell pro-inflammatory responses is unknown. Herein, we describe how TCE affects two murine cell models optimized to recapitulate in vivo interactions between regenerating SM and recruited pro-inflammatory myeloid cells: 1) strained skeletal muscle tissue derived from C2C12 myoblasts, and 2) mature myeloid lineages derived from ex vivo-cultured primary bone marrow. We show that TCE treatment may improve SM regeneration by increasing MHC protein expression plus MCP-1 and HGF secretion. Importantly, TCE treatment modestly reduced myoblast proliferation but without affecting viability, and did not affect proliferation or differentiation-specific protein expression profiles (via imaging flow cytometry) of myeloblasts or derived progenitors. Moreover, TCE treatment reduced levels of reactive oxygen species (ROS) released by activated neutrophils. Our continued analyses will identify how TCE either independently affects damaged SM regeneration or myeloid cell functional responses, or dependently affects the interactions between these disparate cell types upon muscle injury. Our studies may reveal that this natural compound not only improves muscle recovery following damage but also attenuates pro-inflammatory responses of recruited myeloid cells.
RNA-binding protein HuR is required for suppressive function but not development of Foxp3+ CD4+ Tregs
Authors: Atasoy Ulus , Ellis Jason S. , Taylor Tiffany , Ridenhour Suzanne 
Published: January 2023

Abstract
The RNA-binding protein (RBP) HuR (Elavl1) controls differentiation of CD4+ T cells into multiple helper subsets through regulating transcript stability of multiple T helper subset-specific targets. We generated dLck-Cre HuRfl/fl mice, in which HuR is conditionally knocked out in T cells late in thymic development. There was a 5-fold skewing toward HuR sufficient regulatory T cells (Treg) in these mice. HuR KO naïve CD4+ T cells from these mice are also less susceptible to Treg polarization than controls and fail to upregulate Foxp3 following activation. We conditionally ablated HuR in Tregs (Foxp3YFP-Cre HuRfl/fl mouse) (HuR KO). Heterozygous Foxp3YFP-Cre/WT HuRfl/fl females have normal weight gain over time. In stark contrast, both hemizygous Foxp3YFP-CreHuRfl/fl males (39% weight reduction) and homozygous Foxp3YFP-Cre/YFP-Cre HuRfl/fl females (30% reduction) have significant failure to thrive. Heterozygous HuR KO females also have a 5:1 shift in the ratio of HuR− Treg to HuR+ Treg indicating a possible survival bias toward Treg expressing WT levels of HuR. HuR KO mice have features of scurfy mice, including alopecia and stippled tails, as well as multi-organ inflammation which includes lung, skin, stomach and liver. Additionally, naïve HuR KO mice have significantly reduced peripheral Tregs and increases in activated Foxp3− effector T cells. In vitro suppression assays showed reduced suppressive capacity of HuR KO Tregs relative to WT Tregs. Together, these data suggest that HuR is critical for effective Treg function, but is dispensable for the development of Foxp3+ CD4+ Tregs.
The NINJA mouse: a novel model to study tissue-specific peripheral T cell tolerance
Authors: Damo Martina , Joshi Nikhil S. 
Published: January 2023

Abstract
T cell inhibitory pathways induce peripheral tolerance and have evolved to avoid pathogenic autoimmunity. Generally, peripheral tolerance either prevents T cell activation or inhibits T cells during chronic responses, but it is not clear whether these functions are orchestrated by the same mechanisms. Moreover, it is not known if these mechanisms have a tissue-specific usage. Persistent viral infections and cancer leverage the T cell inhibitory pathways involved in peripheral tolerance, thus providing translational relevance to the role of these pathways in disease. However, many of the mechanisms of peripheral tolerance remain understudied, in part because few animal models can distinguish these mechanisms from those driving central tolerance. We have generated a novel mouse model (iNversion INduced Joined neoAntigen, NINJA) that bypasses central and peripheral tolerance by using genetic recombination to create a neoantigen-coding gene for de novo neoantigen expression in any tissue of choice. NINJA expresses LCMV-derived GP33–41 and GP61–80 after induction, enabling investigation of tolerance using well established immunologic tools. Prior to recombination, NINJA mice respond robustly to LCMV-Arm infection, indicating absence of tolerance. However, after recombination, LCMV GP-specific responses are significantly impaired, although mice retain the capacity of developing immunity against unrelated LCMV epitopes. PD-1 is upregulated by tolerized endogenous GP33–41-specific CD8+ T cells after hepatocyte-specific NINJA activation, thus suggesting its involvement in hepatic peripheral tolerance. We therefore propose NINJA as a model to investigate tissue-specific mechanisms of peripheral T cell tolerance.
The unfolded protein response, microRNA-214, and expression of the transcription factor XBP1
Authors: Brewer Joseph W. , Jackson Kevin P. , Lee Eleanor H. , Smith Kelsie M. 
Published: January 2023

Abstract
The transcription factor X-box binding protein 1 (XBP1) plays critical roles in the immune system. For example, XBP1 is required for plasma cell development and can disrupt proper function of tumor-associated dendritic cells. A number of post-transcriptional mechanisms regulate XBP1, but a complete understanding of the processes that govern its expression and activity in distinct situations is lacking. The active form of XBP1, termed XBP1s, is dependent upon cytoplasmic splicing of Xbp1 mRNA by IRE1, a transmembrane endoribonuclease/kinase positioned in the endoplasmic reticulum (ER) membrane. IRE1 is a key signal transducer in the cellular response to ER stress, also known as the unfolded protein response (UPR). The IRE1-XBP1 pathway coordinates a broad program of gene transcription that promotes functions of the secretory pathway and alters various aspects of lipid homeostasis under conditions that perturb the ER environment and/or increase demand on its protein folding capacity. ER stress also activates the UPR signal transducer PERK, an ER transmembrane kinase that mediates efficient repression of protein synthesis. Previous studies have shown that microRNA(miR)-214 can negatively regulate XBP1 expression and is down-regulated during ER stress. Using PERK-deficient mouse embryo fibroblasts, we have found that ER stress-mediated diminishment of miR-214 is partially dependent on the PERK pathway, suggesting a novel mechanism of regulatory crosstalk between the PERK and IRE1-XBP1 branches of the UPR. The significance of miR-214 in the cellular response to ER stress and to XBP1-mediated events is under investigation.
Differential regulation of B cell responses to acute and chronic infection by histone-modifying complexes
Authors: Good-Jacobson Kim , Di Pietro Andrea , Yiannis Callisthenis , Farighi Rohia 
Published: January 2023

Abstract
Molecular regulation of B cell differentiation is critical for formation of immune memory and becomes dysregulated in B cell lymphomas. Alterations in the genomic landscape that allow or restrict access of transcription factors are critical to enact gene expression profiles that in turn drive cell differentiation. Chromatin accessibility can be modulated by enzymes that modify the N-terminal tail of histones. The Trithorax group protein MLL1 forms histone-modifying complexes to permit transcription, whereas the two Polycomb repressor complexes (PRC) work together to repress gene expression. The dynamic regulation of these complexes can modulate B cell fate and function during immune responses. Yet, little is known about the temporal and spatial requirements of MLL1, canonical PRC1 and PRC2 during acute and chronic immune responses. Deletion of the PRC2 member EED (Eedf/fCd23Cre/+ mice) resulted in a complete absence of GC and B cell memory following immunization or influenza infection. Mll1f/fCd23Cre/+ mice also could not mount an effective GC response to immunization, yet their plasmablast response remained intact. In contrast, the canonical PRC1 member BMI-1 was required for plasmablast but not GC responses. Surprisingly, the requirement for EED and MLL1 in a chronic persisting infection differed from acute responses. In contrast to acute responses, Eedf/fCd23Cre/+ mice infected with LCMV-Docile or P. chabaudi had normal GC formation, whereas Mll1f/fCd23Cre/+ mice formed GCs to the acute LCMV strain but not in chronic infection. Together, our data demonstrate the differential requirements of these complexes in B cell fate decisions, as well as suggest epigenetic regulatory checks are subverted in persisting infections.
Hypoxia-Inducible Factors regulate metabolism and germinal center response.
Authors: Cho Sung Hoon , Raybuck Ariel , Kemboi Edna , Boothby Mark R. 
Published: January 2023

Abstract
Germinal centers (GCs) are micronantomic structures that B cells proliferate, are selected for affinity maturation, undergo antibody (Ab) class-switch recombination and differentiate into Ab-secreting plasma cells and memory B cells. Both cell-autonomous and extrinsic metabolic reprogramming have emerged as modulators of T cellmediated immunity. We have shown that GC light zone (LZ) are hypoxic, and the low oxygen tension or persistent stabilization of Hypoxia-Inducible Factor (HIF)-1a and 2a alters B cell physiology and function. Depletion of HIF-1a and HIF-2a in CD4 T cells caused deficiencies of the antibody response due to HIF functions in both B lineage cells and the follicular CD4 subset. Among CD4 T cells, HIF restrained the FoxP3-positive T follicular regulatory (TFR) population while promoting CD40L expression. In the B lineage, HIF promoted humoral responses both through their capacity to promote effective proliferation and via enhancement of plasma cell differentiation. Collectively, these results provide evidence that HIF transcription factors regulate humoral responses via vital functions of B and Tfh cells. We propose that restriction of oxygen in lymphoid structure and organs, which can be altered in pathophysiological status, modulates humoral immune response and memory.
Activation-induced cytidine deaminase mutator activity targeting through phosphorylation
Authors: McBride Kevin M. , Mu Yunxiang , Zelazowska Monika Anna 
Published: January 2023

Abstract
Activation induced cytidine deaminase (AID) initiates immunoglobulin class switch recombination (CSR) and somatic hypermutation (SHM) by deaminating transcribed double stranded DNA to produce U:G mismatches. Subsequent processing of lesions complete SHM or CSR. AID mutator activity predominantly targets the immunoglobulin locus, although “off-target” association also occurs at transcribed regions. The promiscuous targeting has the potential to cause oncogenic mutations, DSBs and chromosome rearrangements and so AID activity must be carefully regulated. How this is accomplished is not completely understood as AID occupancy does not directly correlate with DNA damage, suggesting factors beyond AID association contribute to mutation targeting. It is known that post-translational modifications, in particular AID serine 38 phosphorylation (pS38) regulate AID activity. AID with the inability to be phosphorylated results in deficient CSR and SHM. However, the regulation of pS38 is poorly understood and the contribution of pS38 phosphorylation to off-target AID activity is unknown. Through evaluation of pharmacological inhibitors and activators we identify several that impact AID phosphorylation. We determined that a FDA approved drug, lithium, enhanced AID S38 phosphorylation. Using wild-type B cells and those expressing AID with a S38A mutation, we evaluated the effect of enhanced AID phosphorylation. We find increased off-target mutations, DSBs, and chromosome translocations without an increase in CSR. These studies demonstrate how AID activity can be differentially targeted by phosphorylation to diversify immunoglobulin genes or induce oncogenic lesions.
Targeting colorectal cancer metastasis-initiating cells through hepatic iNKT cells
Authors: Feng Hao , Lu Ai-guo , Wang Jian 
Published: January 2023

Abstract

Aims
To investigate the immune microenvironment modulation of iNKT cells for recognition and elimination of colorectal metastasis-initiating cell (MIC).

Methods
Different subtypes of human colorectal cancer cells and iNKT cells were analyzed by BD LSRFortessa™, TMA, and immunofluorescence(n=138). Microfluidic circulating tumor cell enrichment, Ex vivo 3D co-culture, Quansys Multiplex array, survival data analysis, and Elisa array were performed.

Results
There is a subtype of colorectal cancer stem cell referred as a metastasis-initiating cell (MIC), which do not express upregulated mesenchymal genes but express elevated levels of CD36 (the fatty acid receptor) and other lipid metabolism genes. Intriguingly, those cells overexpress NKG2DL, Various immune cells express NKG2D receptors, including natural killer (NK) cells, CD8+ T cells, and human iNKT cells. Concerning the NKT cells, there is an increase of NKG2D expression on liver resident iNKT cells (P &lt; 0.05). We further observed that hepatic iNKT cells located at the invasive margin had been activated as shown by increased IFN-γ, TNF-α, granzyme B and Ki-67 expression. Furthermore, transmembrane CD1d density and intra/tmCXCL16 expression were also elevated in CD36+colorectal cancer stem cells, those cells showed significantly elevated α-GalCer: CD1d complex formation than other cancer stem cells in an ex vivo iNKT cells activation assay. CD36+cancer stem cells show susceptibility to iNKT cells induced cytotoxicity.
A novel methodology to modulate immune environment using synthetic mRNA
Authors: Xu Yitian , Huang Lu , Kirschman Johnathan L. , Vanover Daryll , Tiwari Pooja M. , Santangelo Philip J. , Shen Xiling , Russell David G. 
Published: January 2023

Abstract
As the next generation of gene therapy, synthetic mRNA therapy is known for its intrinsic advantages to avoid genomic integration that associated with DNA-based therapy, and its prolonged production of target proteins over traditional recombinant protein therapy. Synthetic mRNA therapy has been studied in various disease models including cancer, infectious disease and cardiovascular disease. However, these studies focus mainly on expressing proteins with direct therapeutic effect or antigens to elicit an immune response. It is not well established that whether synthetic mRNA can be taken advantage in cell based therapies in vivo to recruit cells of interest and modify them locally. Here we reported a synthetic mRNA based immune-modulation method, exampled by using Ccl2 and Ccl3 synthetic mRNA to recruit a certain population of monocyte in a non-inflamed manner. These recruited monocytes exhibit neither bactericidal or tissue-repairing behaviors, but stay in a neutral, non-programmed state. With additional Ifn-g mRNA and Il-4 mRNA, these cells can be polarized to different phenotypes. Furthermore, the monocytes recruited by Ccl3 and Ifn-g mRNA are able to launch the most rapid and strong superoxide burst, which demonstrates their active functionality upon proper signals. In summary, our data established a synthetic mRNA based immune-modulation system, which allows recruitment and modification of specific immune cell populations in a precise and localized manner, and more importantly, proves the concept that synthetic mRNA can be utilized in cell based therapies to replace the time-consuming and labor-demanding process of modifying patients’ own cells ex vivo and transferring back to patients afterwards.
Sex differences in the acute neuroinflammatory events after experimental traumatic brain injury
Authors: Doran Sarah J. , Ritzel Rodney , Glaser Ethan , Henry Rebecca , Faden Alan , Loane David 
Published: January 2023

Abstract
Traumatic brain injury (TBI) is sexually dimorphic, impacting males 3 times more than females. Neuroinflammation is a key secondary response activated following TBI, where it has recently been shown that TBI leads to an exacerbated neuroinflammatory response in males versus female mice. The aim of this study was to investigate potential differences in microglial activation at baseline and acute time points after experimental TBI. Age matched male and female C57BL/6 mice underwent moderate-to-severe controlled cortical injury (CCI) and brain samples were collected for flow cytometry analysis at 1, 3, and 7 days post-injury (dpi). In addition, animals underwent motor and cognitive behavioral tasks. Baseline microglia function in females showed significantly higher production of pro-inflammatory cytokines (TNF-α, IL-1β), whereas male microglia exhibited increased levels of reactive oxygen species (ROS) and greater phagocytic activity. On flow cytometry analysis, in both sexes pro-inflammatory cytokines, ROS, and phagocytic activity all increase 1dpi, remain elevated at 3dpi, returning to near baseline levels by 7dpi. At 1, 3, and 7 dpi leukocytes infiltrating the brain after injury in males and females produced more TNF-α, IL-1β, TGF-β, and ROS and showed greater phagocytic activity than microglia. However, at 1 dpi females have significantly less infiltrating peripheral immune cells perhaps indicating that peripheral cells are driving acute inflammation after TBI, leading to an early sex difference in behavior. This data indicates that while microglia in both sexes may respond similarly after TBI, there are significant sex differences in peripheral immune activation and infiltration after TBI that may affect acute outcomes.
Morphine dysregulates Paneth cell antimicrobial peptide secretion in a TLR2 dependent manner.
Authors: Jalodia Richa , Meng Jingjing , Sharma Madhulika , Ramakrishnan Sundaram , Roy Sabita 
Published: January 2023

Abstract
Opioids are the gold standard for moderate to severe pain management. Although, the co-morbidities associated with chronic morphine use on systemic immune function has been well demonstrated by our lab and others its effect on mucosal immunity and gut homeostasis are less well defined. We have recently demonstrated that morphine treatment disrupts intestinal epithelial barrier function and suppresses systemic immune function leading to altered gut microbial dysbiosis and inflammation. We have also shown in vivo that morphine can alter the immune response by APCs leading to reduced host immune response. However, the cross talk between the gut microbiome and host intestinal epithelium and immune cells has never been explored. Paneth cells are one of the main secretory component of intestinal epithelial layer that secrete antimicrobial peptides which maintains gut homeostasis between pathogenic and commensal microbes. They also secrete pro-inflammatory cytokines which regulate the functions of mucosal immune cells. In both a murine in vivo model and in an in vitro organoid epithelial culture model we show a direct effect of morphine on paneth cells. Intraperitonial morphine treatment significantly increases the transcription level of antimicrobial peptides, a-defensins, lysozyme, Regg as well as intestinal pro-inflammatory cytokine IL1b, IL6 and TNFa levels in C57/B6 mice model. These results are also corroborated in in vitro organoid cultures. Surprisingly, these effects were completely abolished in a Toll-like receptor-2 (TLR2) knock out mice suggesting that the effect is mediated through TLR2. The role of TLR 2 and the cell type that mediates morphine’s effects will be further investigated using TLR2 floxed mice.
Lactic acid suppresses LPS-induced cytokine production in mast cells by limiting glycolysis and ATP availability
Authors: Caslin Heather , Abebayehu Daniel , Qayum Amina Abdul , Hoeferlin Alexis , Chalfant Charles 
Published: January 2023

Abstract
Despite a mortality rate of 30–50%, there are no targeted molecular treatments for sepsis. Our understanding of the secondary immunosuppressive phase is recent, and it is unclear whether many mediators are helpful or detrimental to patient survival. Elevated blood lactate and slow lactate clearance are associated with mortality, however, any regulatory roles are currently unknown. Because mast cells can be activated systemically and contribute to sepsis, this project aims to elucidate lactic acid effects on mast cell activation and signaling. Lactic acid significantly suppressed LPS-induced cytokine and chemokine production as well as NFκB transcription in bone marrow derived and peritoneal mast cells. These effects were dependent upon pH and MCT-1 transporter activity. Further, lactic acid significantly suppressed cytokine and chemokine induction following LPS-induced septic shock in vivo. We also examined the role of lactic acid as a feedback regulator of glucose metabolism. Lactic acid treatment reduced glucose uptake, lactate export, and hexokinase 2 expression following LPS activation. The glycolytic inhibitors 2-deoxyglucose, sodium oxamate, or dichloracetate mimicked lactic acid effects, suppressing LPS-induced cytokine production and NFκB transcription. Furthermore, adding ATP to the culture media at the time of LPS activation reversed lactic acid effects. These results indicate that suppressing glycolysis and ATP production are necessary and sufficient for lactic acid effects. Future studies should target enhancing glycolysis and ATP production to improve immune function and counteract lactic acid effects in sepsis.
Vagal tonic activity modulates immune suppression in sepsis survivors
Authors: Rana Minakshi , Son Myoungsun , Fei Yurong , La Bella Andrea , Ochani Mahendar , Chiu Pui Yan , Sherry Barbara , Diamond Betty 
Published: January 2023

Abstract
Sepsis survivors exhibit persistent immune dysfunction and compromised quality of life with premature mortality due to increased vulnerability to infections. Previously we demonstrated in a cecal ligation and puncture (CLP) model, sepsis survivors had a reduced TNFα response to LPS-challenge in vivo. The vagus nerve is known to modulate TNFα production. To evaluate the role of the vagus nerve in the diminished TNFα production, sepsis-surviving mice were subjected to bilateral subdiaphragmatic vagotomy 2 weeks post-CLP. CLP-surviving vagotomized mice exhibit increased (p&lt;0.05) TNFα levels in response to LPS-challenge 4 weeks post surgery compared to CLP. Moreover, vagus nerve stimulation in sham mice dampened (p&lt;0.05) the LPS-induced TNFα response while it had no effect in CLP-surviving mice; suggesting that vagus nerve signaling is constitutively active in CLP-sepsis survivors. To identify whether there was an alteration in the number of acetylcholine-producing T cells that relay the vagus signal to splenic macrophages, we used ChAT-EGFP mice. Our findings show that the frequency of splenic ChAT-EGFP+ cells among memory CD4+CD44highCD62LlowT cells is increased (p&lt;0.001) in CLP-surviving mice compared to sham, and vagotomy in these mice resulted in decreased (p&lt;0.01) frequency of ChAT-EGFP+ cells, buttressing the conclusion that the vagus nerve is constitutively firing action potentials to activate more ChAT+ T cells. Methyllycaconitine, the α7 nicotinic acetylcholine receptor antagonist, increased (p&lt;0.01) LPS-induced TNFα secretion in CLP-surviving mice compared to saline treated-CLP. In summary, our study demonstrates that altered vagus nerve activity contributes to the immune impairment in sepsis survivors.