bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differences in the M1 and M2 macrophage subtypes between the sexes determine susceptibility to Francisella tularensis infection
Authors: Sanchez Michelle A , Spencer Charles T 
Published: January 2023

Abstract
Francisella tularensis is the causative agent of the human disease tularemia. F. tularensis infects a variety of cells, including macrophages, in order to cause pathogenicity. As few as 10 inhaled microorganisms cause a lethal infection by over-activating the host’s own inflammatory response. Differences in the intensity of the inflammatory response exist between the sexes which leads to differences in sensitivity to autoimmune and infectious disease. Males tend to be more susceptible to infectious diseases whereas females tend to be more susceptible to autoimmune diseases. However, our preliminary data unexpectedly demonstrated that female mice were more susceptible to F. tularensis--mediated disease than male mice. We hypothesized that female macrophages respond to F. tularensis infection by generating a more intense inflammatory response which makes females more susceptible to F. tularensis. Indeed, female mice infected with F. tularensis generate significantly more inflammatory M1 macrophages compared to male mice. Furthermore, naïve M1 and M2 macrophages were infected in vitro to directly compare cellular responses between male and female mice. On a per cell basis, M1 macrophages from female mice generated a more robust inflammatory response compared with M1 macrophages from male mice. This suggests that M1 macrophages from females respond more strongly to infection resulting in the heightened inflammatory response.
Early innate interactions drive alveolar macrophage localization and effector function during Mycobacterium tuberculosis infection
Authors: Dunlap Micah , Howard Nicole , Das Shibali , Bobba Suhas , Rangel-Moreno Javier , Khader Shabaana A 
Published: January 2023

Abstract
Mycobacterium tuberculosis (Mtb) is the leading cause of death by infectious agent in the world today, infecting roughly ¼ of humans. Despite this, the mechanisms of early pathogenesis and host protective innate immune responses remain poorly understood and uncharacterized.
Lung resident Alveolar Macrophages (AMs) are the first host contact with Mtb bacilli after inhalation and thus key mediators of the early pulmonary immune response. AMs are generally believed to reside entirely in the airway, but it was recently demonstrated that they have the capacity to egress and enter into granulomas during pulmonary infection with hypervirulent Mtb. Furthermore, we found that airway and non-airway AMs display distinct transcriptional profiles that suggest differential effector functions based on compartmental localization. The variety of effector function pathways expressed by non-airway AMs are primarily mediated by NFkB signaling and are indicative of an M1 activation phenotype, which shifts the classic paradigm of AMs as permissive reservoirs for Mtb replication.
In the current work, we examine the host and Mtb factors/signals that modulate these compartmentally distinct AM effector functions and how these specific interactions determine protective or detrimental outcomes for the host. We examine the various functions that AMs contribute to the early immune response, focusing on migration from the airway, cellular interactions with epithelial or recruited immune cells, Mtb phagocytosis and killing, and inflammatory cytokine production. We also examine how specific Mtb cell wall lipid factors that mediate drug resistance and virulence can modulate these AM effector functions, thus skewing the host immune response.
Elucidation of the respective roles of itaconate and nitric oxide in the nuclear accumulation and activation of Nrf2 in activated macrophages
Authors: Krepel Stacey A , Gonzalez-Cotto Marieli , Palmieri Erika M , McVicar Daniel W 
Published: January 2023

Abstract
Nrf2 is a transcription factor that, under basal conditions, is produced in the cytosol and is marked for degradation by its repressor Keap1. Oxidative stress causes Keap1 to release Nrf2, and it accumulates in the nucleus to upregulate certain antioxidant gene targets. Itaconate, the metabolic product of IRG1, has been suggested to play a role in alkylating Keap1, leading to the release of Nrf2. However, there is much ambiguity and even controversy surrounding this role of itaconate. Our study therefore seeks to definitively elucidate the role of itaconate in the regulation and activation of Nrf2. Here we utilize expression analysis and targeted metabolomics in bone marrow-derived macrophages isolated from varying murine backgrounds (Acod1−/−, Nos2−/−, and double knockouts). Despite previously published data suggesting a role for itaconate in Nrf2 activity, our data demonstrate a significant role of Nos2, but not itaconate, in Nrf2 activation, as Acod1−/− mice show little change in the activity of Nrf2 transcription targets, while Nos2−/− mice show severe impairment of Nrf2 gene target activity. For Nrf2 to properly upregulate its gene targets, it must be released from Keap1, phosphorylated, and then allowed to translocate to the nucleus; all three must occur. This may help explain why some studies have found itaconate to be important in Keap1’s regulation of Nrf2, while others demonstrate that this same itaconate mechanism produces comparatively little Nrf2 activity.
Basal TCR signaling drives the functional heterogeneity of naïve CD4+ T cells
Authors: Au-Yeung Byron B , Weiss Arthur , Zinzow-Kramer Wendy 
Published: January 2023

Abstract
Prior to their activation with high affinity foreign peptides presented by MHC Class II (pMHC), naïve CD4+ T cells experience weak “tonic” or “basal” T cell receptor (TCR) signals in response to self-pMHC. We used a combination of the Nur77-GFP reporter transgene and the surface protein Ly6C to visualize the strength of basal TCR signaling in peripheral T cells, and aimed to determine how the strength of basal TCR signaling affects the function of naïve CD4+ cells. The combination of Nur77-GFP and Ly6C enables visualization of a broad range of basal TCR signaling; cells experiencing the weakest basal TCR signals are GFP low Ly6C+, whereas cells experiencing the strongest basal TCR signals are GFP high Ly6C–. We find that there is functional heterogeneity in the naïve CD4+ T cell population, even if they express identical transgenic TCRs, such as the OT2 or AND TCR. Cells experiencing weak basal TCR signaling generate more sustained IL-2 responses and proliferate to a greater extent than cells experiencing moderate basal TCR signal strength. The GFP high Ly6C–cells consistently mounted attenuated IL-2 and proliferative responses, and expressed proteins associated with anergy, such as Grail and Cbl-b. This model is supported by RNA-seq analysis, which identified approximately 100 genes that were more highly expressed in cells experiencing strong basal TCR signaling. Furthermore, ATAC-seq analyses revealed over 3000 loci that were differentially accessible in cells experiencing strong basal TCR signals. We propose that naïve CD4+ cells exhibit phenotypic and functional heterogeneity, and that the source of their heterogeneity is due to the varying strengths of basal TCR signaling experienced by individual T cells.
CNS lymphangiogenesis regulates fluid homeostasis and immunity during neuroinflammation
Authors: Hsu Martin , Choi Yun Hwa , Laaker Collin , Karpus William J. , Sandor Matyas , Fabry Zsuzsanna 
Published: January 2023

Abstract
Recent reports have described meningeal lymphatic vessels residing in the dural layer surrounding the dorsal and basal regions of the brain as well as near the cribriform plate. While all three regions are able to uptake CSF macromolecules, it is unknown how cells and fluid from the CSF-filled subarachnoid space gain access through the blood-CSF arachnoid barrier and into dural lymphatics. In this study, we expand on our previous findings demonstrating the capability of neuroinflammation-induced cribriform plate lymphangiogenic vessels in draining CSF and leukocytes. These lymphatics reside in an optimal location for CSF drainage due to gaps in the arachnoid epithelial layer separating the dura from the subarachnoid space and correlate with increased CSF accumulation near the cribriform plate during neuroinflammation. This is in contrast to other lymphatics residing in the dural layer dorsal and basal to the brain, which are separated from CSF by a complete and uninterrupted arachnoid layer. Additionally, we show lymphangiogenic cribriform plate lymphatic vessels dynamically up-regulate proteins to increase dendritic cell binding and T-cell tolerance during autoimmunity. These data identify cribriform plate lymphatic vessels as dynamic structures that are able to undergo lymphangiogenesis to facilitate fluid drainage and regulate adaptive immunity during neuroinflammation.
In Silico Modeling of Metabolic State in Single Th17 Cells Reveals Novel Regulators of Inflammation and Autoimmunity
Authors: Wagner Allon , Wang Chao , DeTomaso David , Pacheco Julian Avila , Zaghouani Sarah , Fessler Johannes , Akama-Garren Elliot , Pierce Kerry , Ron-Harel Noga , Haigis Marcia , Sobel Raymond A , Clish Clary , Regev Aviv , Kuchroo Vijay K , Yosef Nir 
Published: January 2023

Abstract
Cellular metabolism is a major regulator of immune response, but it is difficult to study the metabolic status of an individual immune cell using current technologies. Here, we present Compass, an algorithm to characterize the metabolic landscape of single cells in silico based on single-cell RNA-Seq and flux balance analysis. We used Compass to study the landscape of metabolic heterogeneity in Th17 cells and search for novel metabolic regulators of their inflammatory function. In central carbon metabolism, Compass predicted a metabolic switch between glycolysis and fatty acid oxidation that mirrors the Th17 vs. Treg phenotype, which we validated through transcriptomic, metabolic and functional assays. The TCA cycle was predicted to break at two points, both of which have been independently identified by other groups in M1 macrophage polarization. Surprisingly, and contrary to common immunometabolic understanding, Compass predicted that glycolysis too was divided into functional modules, and that one of them supported an anti-inflammatory phenotype. We validate the paradoxical prediction and demonstrate that inhibition of this module promotes a pro-inflammatory transcriptional program in Th17 cells, resulting in neuroinflammation in an adoptive transfer model of autoimmune disease. In conclusion, Compass is a widely applicable algorithm to characterize metabolic states at single cell resolution. It allows associating cellular metabolic states with effector functions and detection of metabolic targets that regulate effector phenotypes. We expect it to become a widely used tool with the increasing availability of single-cell RNA-Seq data, spurred by efforts such as the human cell atlas.
Ssu72 phosphatase directly binds to ZAP-70, thereby providing fine-tuning of TCR signaling and preventing autoimmunity
Authors: ko jaesung , Jeong Dongjin , Koh Jaemoon , Jung Hyeryeon , Jung Kyeong Cheon , Jeon Yoon Kyung , Kim Hye Young , Yi Eugene C , Lee Ho , Lee Chang Woo , Chung Doo Hyun 
Published: January 2023

Abstract
ZAP-70 is required for initiation of TCR signaling. However, the mechanism by which ZAP-70 regulates the fine-tuning of TCR signaling remains elusive. Here, we found that the phosphatase Ssu72, originally known to regulate RNA polymerase II activity in the nucleus, contributed to the fine-tuning of TCR signaling by binding to ZAP-70. Affinity purification–mass spectrometry and an in vitro assay demonstrated specific interaction between Ssu72 and ZAP-70 in T cells. Upon TCR stimulation, Ssu72-deficient T cells increased the phosphorylation of ZAP-70 and downstream molecules, and exhibited hyper-responsiveness, which was restored by reducing ZAP-70 phosphorylation. Cd4-CreSsu72fl/fl mice showed a defect in the thymic development of invariant NKT cells and reductions in CD4+ and CD8+ T cell numbers in the periphery, but more CD44hiCD62Llo memory T cells and fewer CD44loCD62Lhinaïve T cells compared with wild-type mice. Furthermore, Cd4-CreSsu72fl/fl mice developed autoimmunity spontaneously at 6 months. In conclusion, Ssu72 regulates the fine-tuning of TCR signaling by binding to ZAP-70 and regulating its phosphorylation, thereby preventing autoimmunity.
Aberrant NKG2D receptor expression on CD 4 T cells were considerably reduced by accumulated effect of traditional Thai massage in Thai elderly
Authors: SORNKAYASIT KANDA , PHOKSAWAT WISITSAK , LEELAYUWAT CHANVIT , EUNGPINICHPONG WICHAI , JUMNAINSONG AMONRAT 
Published: January 2023

Abstract
Natural killer group 2, member D (NKG2D) is a potent activating receptor of the immune system that can express on most of T cells. The NKG2D expression on CD 4 T cells have elucidated as pathogenic immune cells in chronic inflammatory diseases also elderly. A possible effect of traditional Thai massage (TTM) on immunity via inflammatory response and homeostasis was supposed. TTM is an exclusive technique of deep tissue massage by acupressure along ten meridian lines and combined muscle stretching. Thus, this study aimed to investigate the effect of TTM on pathogenic immune cells in elderly. A randomized crossover trial was performed in 12 Thai elderly participants aged 67.7±5.12 years. Each of them underwent 6 sessions of 1-hour TTM/rest (once weekly) for 5 weeks with a 30-day washout period. The immunophenotyping was specifically investigated on cell surface markers using monoclonal antibody conjugated with different fluorochromes staining by flow cytometry. The results showed that the participants had risen NKG2D expression on CD 4 T cells before having TTM. The pathogenic immune cells were considerably reduced after having the sessions accumulated of TTM. The pairwise comparison between before and accumulated effect of NKG2D expressions on CD4+ T cells, CD4+28+ T cells, and CD4+28null T cells were significantly decreased (p=0.003, p=0.005, and p=0.005, respectively) in the TTM period whereas no significantly change was found during the control period. We conclude that TTM might promote immunity by selectively decreasing pathogenic immune cells in elderly. However, the mechanism should be clarified in the future.
A PI(4,5)P2-derived “gasoline engine model” for the sustained B cell receptor activation
Authors: Liu Wanli 
Published: January 2023

Abstract
To efficiently initiate activation responses against rare ligands in the microenvironment, lymphocytes employ sophisticated mechanisms involving signaling amplification. Recently, a signaling amplification mechanism initiated from phosphatidylinositol (PI) 4, 5-biphosphate [PI(4,5)P2] hydrolysis and synthesis for sustained B cell activation has been reported. Antigen and B cell receptor (BCR) recognition triggered the prompt reduction of PI(4,5)P2 density within the BCR microclusters, which led to the positive feedback for the synthesis of PI(4,5)P2 outside of the BCR microclusters. At single molecule level, the diffusion of PI(4,5)P2 was slow, allowing for the maintenance of a PI(4,5)P2 density gradient between the inside and outside of the BCR microclusters and the persistent supply of PI(4,5)P2 from outside to inside of the BCR microclusters. Here, we review studies that have contributed to uncovering the molecular mechanisms of PI(4,5)P2-derived signaling amplification model. Based on these studies, our recent work supported a “gasoline engine model” in which the activation of B cell signaling inside the microclusters is similar to the working principle of burning gasoline within the engine chamber of a gasoline engine.
Impact of Epstein-Barr Virus LMP2A-dependent BTK/STAT3 activation on resting and activated murine B cells
Authors: Swanson-Mungerson Michelle Anne , Del Toro Rosalinda , Zanotti Brian , Incrocci Ryan 
Published: January 2023

Abstract
Epstein-Barr virus (EBV) latently infects over 90% of the population and is associated with the development of numerous autoimmune diseases and B cell lymphomas. Therefore, understanding the impact of latency proteins on B cell survival and function is vital. One EBV latency protein, LMP2A, acts as a BCR mimic to promote B cell survival, increase B cell activation, and accelerate tumor development in murine mouse models. Our laboratory identified that LMP2A activates the PI3K/BTK/STAT3 pathway in human B cell lymphomas to increase IL-10 production that promotes survival. However, the ability of LMP2A to activate BTK and STAT3 in non-transformed B cells is unknown. To test this possibility, we returned to the LMP2A transgenic mouse model as a source of resting B cells that express LMP2A. To determine if LMP2A activates STAT3 in the mouse model, resting B cells from wildtype and LMP2A-transgenic mice were isolated and STAT3 phosphorylation was assessed by Western blot analysis. Our data indicate that LMP2A-postitive B cells express higher levels of phosphorylated STAT3 than wildtype controls. We further analyzed whether the LMP2A-dependent activation of STAT3 resulted in an increase in STAT3-dependent targets. Flow cytometric analysis indicates that the addition of STAT3 inhibitors to activated LMP2A-expressing B cells blocked the LMP2A-dependent increase in STAT3 targets in comparison to wildtype controls. These data suggest that LMP2A increases the activation of the oncogene STAT3 in resting B cells, which may contribute to the development of EBV-associated tumors and autoimmune diseases.
B cell-intrinsic STAT3 regulates the germinal center dark zone
Authors: Chodisetti Sathi Babu , Fike Adam , Bricker Kristen , Domeier Phillip P , Choi Nicholas M , Rahman Ziaur 
Published: January 2023

Abstract
Germinal centers (GCs) are sites for antibody diversification, somatic hypermutation (SHM) and antigen specific B cell selection. GCs are anatomically divided into two distinct areas known as dark zone (DZ) and light zone (LZ) where SHM and clonal selection occurs, respectively. Although previous studies have suggested a B cell-intrinsic role of STAT3 in GC maintenance and antibody responses, how STAT3 signaling in B cells may maintain GCs for B cell selection is not clear. Using immunization and infection models, we show that STAT3 in B cells regulates the GC DZ, resulting in decreased high affinity antibody production. STAT3 deficient DZ B cells demonstrate a decreased cell proliferation and increased apoptotic activity. Further, STAT3 deletion in B cells led to defects in plasma cell formation and B cell memory response. Using GC B cell specific STAT3 conditional knockout mice and GC B cell culture system, we show that STAT3 deficient GC B cells display low amounts of FOXO1, a critical transcription factor required for GC DZ program. Transcriptomic analysis of GC B cells from STAT3 deficient and sufficient mice reveals STAT3-mediated gene regulation of multiple cellular pathways known to be involved in GC DZ maintenance. In conclusion, STAT3 signaling in B cells controls the GC DZ, which, in turn, helps maintain GCs for high-affinity antibody production. Our findings identify STAT3 as a novel target for enhancing humoral immunity as well as for the treatment of diseases involving abnormal GC activity.
The Notch-Myc signaling axis sets the division-differentiation clock in marginal zone B cells
Authors: Gaudette Brian T. , Roman Carly , Atria Daniela Gomez , Maillard Ivan , Allman David 
Published: January 2023

Abstract
Lymphocyte differentiation is often tightly linked to mitosis. Clonal bursts due to antigen- or TLR-driven responses increase numbers of responding cells and may also facilitate changes in gene expression and chromatin needed for effector cell differentiation. Alternatively, to guard against rapid infection, lymphocyte pools may also contain cells poised for effector differentiation with minimal proliferation. Using cell cycle inhibitors or induced mutation of CDK1, we directly compared the impact of arresting mitosis on early plasma cell (PC) differentiation for naive follicular and marginal zone (MZ) B cells. MZ B cells reside in the marginal sinus of the spleen where they are positioned to respond rapidly to blood borne microbes. Whereas PC differentiation from follicular B cells occurred after only 4 or more divisions and was highly dependent on mitosis, MZ B cells yielded PCs much faster and despite full cell cycle blockade. Furthermore, short-term withdrawal of Notch signaling in MZ B cells in vivo caused rapid and robust down-regulation of large numbers of established Myc-regulated genes, and resulted in division/differentiation kinetics that mirrored follicular B cells. Altogether these results suggest that ongoing Notch signaling establishes a differentiation-poised state in MZ B cells needed for rapid division-independent antibody responses.
PI3K-dependent Reprogramming of Hexokinase Isoforms Regulates B Lymphocyte Metabolism
Authors: Marshall Aaron J , Mejia Edgard , Hou Sen , Sher Affan , Hatch Grant , Aliani Michel 
Published: January 2023

Abstract
The PI3K signalling pathway is known to regulate B cell metabolic programming upon activation, but the mechanisms involved are not well understood. Here we find that the PI3K pathway controls reprogramming of hexokinases (HKs), the enzymes that convert glucose into glucose-6-phosphate as a key rate-limiting step of glycolysis and other metabolic pathways. In primary mouse B cells, PI3K pathway inhibition substantially impaired the activation-induced increase in extracellular acidification rates (ECAR), a measure of glycolysis. In contrast, B cells isolated from PI3Kdelta gain-of-function mutant mice exhibit elevated ECAR. We find that B cell activation substantially elevates protein levels of HK2 and HK3 isoforms, but not HK1, in a PI3K-dependant manner. PI3K or mTOR inhibition significantly reduced induction of HK2 and HK3 expression, whereas Akt inhibition did not affect HK isoform expression. In human B lymphoma cells, HK isoforms differ significantly in their degree of mitochondrial localization, with HK1 being mitochondrial, HK3 being cytoplasmic and HK2 present in both mitochondria and cytoplasm. To assess whether HK isoforms have unique non-redundant functions, HK2-deficient B lymphoma cells were generated and were found to exhibit decreased ECAR as well as significant changes in metabolomic profile, despite normal expression and localization of HK1 and HK3. Taken together, our study reveals that PI3K-dependant reprogramming of hexokinase isoforms can impact on B cell glycolysis and other metabolic pathways. Studies in progress are examining the functional importance of HK2 in antibody responses using mice with B cell-specific deletion of this enzyme.