bluuebunny/crossref_metadata_2025_split huggingface dataset:
Localized immune dysregulation is associated with lung injury in severe pediatric COVID-19
Authors: Korenberg Rebecca C , Bell Joseph N , Bradley Marissa C , Connors Thomas J 
Published: August 2023

Abstract
Acute respiratory distress syndrome (ARDS) is a common and devastating consequence of SARS-CoV-2 infection in adults, however severe lung injury is a rare manifestation of COVID-19 in children. Aberrant local immune responses are known to drive lung pathology in adults, but little is known about localized immune responses in children with respiratory failure due to COVID-19. We obtained blood and respiratory tract samples from children (n=35, aged 1 month to 18 years) admitted to the hospital for COVID-19, stratifying by presence of respiratory failure (n=15). We defined the cytokine and chemokine profile of severe disease using a 71 analyte Luminex panel. Children with respiratory failure were found to have increased circulating levels of leukemia inhibitory factor (LIF), a growth factor upregulated during pulmonary inflammation. The local environment revealed significant inflammation with increased levels of pro-inflammatory cytokines including IL-6, IL-8, and IL-33 among others. Application of high dimensional flow cytometry to define immune cell subsets revealed elevated proportions of monocytes in both circulating and local environments. Monocytes demonstrated decreased expression of HLA-DR and CD86, suggesting an immunoparalysis phenotype, previously associated with severe COVID-19 in adults. Further, effector memory T cells in the airway exhibited an exhausted phenotype with high levels of PD-1 expression. Together this analysis reveals a highly inflammatory and dysregulated immune response underlies SARS-CoV-2 induced pediatric lung injury. These findings suggest a shared pathway with adult COVID-19 ARDS and provide new insights into the immune mechanisms associated with severe COVID-19 in children.
Supported by grants from NIH (K23AI141686)
Calming the storm: Immunoregulatory receptor NLRX1 and its role in the immune response to SARS-CoV-2
Authors: Ivester Hannah , Woolls Mackenzie , Morrison Holly A , Tupik Juselyn D , Chuong Christina , Finkielstein Carla , Duggal Nisha , Weger James , Allen Irving C 
Published: August 2023

Abstract
One of the most characteristic clinical disease presentations of severe COVID-19 is the ‘Cytokine Storm,’ stemming from dysregulation of the immune response. This overproduction of proinflammatory cytokines in response to SARS-CoV-2 is responsible for Acute Respiratory Distress Syndrome (ARDS) in adult patients and the Multisystem Inflammatory Syndrome (MIS) of pediatric patients hospitalized with severe COVID-19. Pattern recognition receptor NLRX1 is a member of the NOD-like receptor family with complex involvement in antiviral immunity. It has been reported in the literature in many contexts to be anti-inflammatory by inhibiting NF-kB and interferon signaling-critical pathways in anti-SARS-CoV-2 immunity. Here we show that loss of NLRX1 impacts immune responses to SARS-CoV-2 both in cell culture and in mice. While Nlrx1−/− mice showed similar overall morbidity, there were temporary increases in weight loss at multiple time points post infection. SARS-CoV-2 infection of Nlrx1−/− mice also resulted in an increase in viral titer in the lungs at 2 dpi, despite having higher degrees of airway inflammation. Data in both cell culture and animal challenges report differences in immune activation, showing differences in cytokine production with changes in expression of NLRX1. Together, these experiments uncover another enigmatic function of NLRX1 while simultaneously offering pathways related to NLRX1 as possible therapeutic targets to help mitigate the effects of the ‘cytokine storm’ of severe COVID-19. Finally, these data also add to the growing field regarding SARS-CoV-2 and its pathobiology in an understudied context of immune regulation and continue to explore NLRX1 and its many curious roles in antiviral immunity.
Interferon-β treatment reverses the detrimental effect of B cell depletion therapy on respiratory virus infection
Authors: Allushi Bujana , Chlebicz Magdalena , Turner Sean , Kovats Susan , Axtell Robert C 
Published: August 2023

Abstract
There are several disease-modifying therapies (DMTs) used as treatments for multiple sclerosis. Depending on their mechanism, DMTs can increase morbidities of viral infections in patients, including SARS-CoV2 and influenza A virus (IAV). B cell depletion (BCD) with anti-CD20 antibodies and interferon-β (IFN-β) are two popular DMTs for MS. BCD increases the morbidity of acute viral infections in patients, whereas the antiviral properties of IFN-β are postulated to protect against infection. This study determined how BCD and IFN-β alone or in combination modulate IAV infection in mice. For BCD, we treated mice with 3 doses of anti-CD20 antibodies every 5 days beginning 7 days prior to IAV infection. For IFN-β, mice were treated on day 1 and 2 post infection. Mice treated only with BCD lost more weight compared to control mice. This increased morbidity was linked with higher levels of viral RNA and more neutrophils and inflammatory monocytes in the lungs at day 9 post-infection. T cell response to IAV was not altered by BCD. Mice treated only with IFN-β had no alteration in weight loss or myeloid cell infiltration in the lungs compared to controls. When adding IFN-β to BCD therapy, mice had significantly less weight loss and lower numbers of neutrophils and inflammatory monocytes in the lung compared to mice with BCD only. Addition of IFN-β to BCD did not improve IAV clearance. Our findings show that BCD increases virus-induced morbidity in mice, which reflects data from MS patients. Here we provide preclinical data showing that the addition of IFN-β can reverse the detrimental effect of BCD on viral infection. Therefore, the combination of non-interacting biologic therapies may mitigate morbidity during viral infection.
Tlr5 deficiency exacerbates lupus-like disease in the MRL/lpr mouse model
Authors: Alajoleen Razan M , Oakland David N , Estaleen Rana , Shakeri Aida , Lu Ran , Appiah Michael , Sun Sha , Reilly Christopher M , Luo Xin M 
Published: August 2023

Abstract
A leaky gut has been linked to numerous autoimmune disorders, including systemic lupus erythematosus (SLE). We had previously reported significant upregulation of anti-flagellin antibodies in the blood of SLE patients and lupus-prone MRL/lpr mice, which led to our hypothesis that a leaky gut drove SLE through bacterial flagellin-mediated activation of toll-like receptor 5 (TLR5). Here, we investigated the initiation and progression of lupus-like disease in MRL/lpr mice with global Tlr5 deletion generated by CRISPR-Cas9. Contrary to our hypothesis that the deletion of Tlr5 would attenuate lupus, our results showed exacerbation of lupus-like disease with Tlr5 deficiency in MRL/lpr mice. A significantly higher level of proteinuria was observed in Tlr5−/− female MRL/lpr mice compared to Tlr5+/− and Tlr5+/+ female littermates, suggesting aggravated glomerulonephritis with Tlr5 deficiency. In the kidney, the deletion of Tlr5 significantly increased renal infiltration of activated conventional and monocyte-derived dendritic cells. Spleen, mesenteric and axillary/cervical lymph node to body weight ratio were also significantly increased in Tlr5−/− MRL/lpr mice compared to Tlr5+/− and Tlr5+/+ littermates, with the effects more pronounced in female mice, suggesting that the deletion of Tlr5 impacted lymphoproliferation in addition to lupus nephritis. We are currently analyzing the lymphoid tissues to reveal potential cellular mechanisms. Notably, Tlr5 deficiency did not change the existing leaky gut in either female or male MRL/lpr mice. Future studies will elucidate the underlying mechanisms by which the deletion of Tlr5 modulates cellular functions to exacerbate lupus.
Inflammatory bowel disease (IBD)-specific immune cell recruitment and response can be modulated with anti-TNF-α therapies in the human Colon Intestine-Chip
Authors: Kanellias Marianne , Woodham Andrew W , Cespedes Adriana V , Apostolou Athanasia , Kujala Ville J , Ewart Lorna , Carman Christopher V 
Published: August 2023

Abstract

Objective
Inflammatory bowel disease (IBD) is a complex inflammatory disease, for which few effective therapies exist. The goal of our current work was to show: i) that such a complex, immune cell-driven pathogenesis could be captured on Emulate’s human Colon Intestine-Chips; and ii) that this could be used as a novel human-centric system to support IBD drug development including anti-TNF-α antibodies.

Methods
PBMCs were perfused through the vascular (bottom) channel in untreated ‘resting’ or cytokine-‘primed’ Colon Intestine-Chips. Clinically relevant IBD drugs, including anti-TNF-α antibodies (Humira and Cimzia), as well as dexamethasone and AJM300 were administered through the vascular channel during PBMC administration. Total cell recruitment, effluent biomarker secretion (cytokines, calprotectin, C-reactive protein), and barrier function were analyzed for 72 hours.

Results
α4β7+ ‘gut-tropic’ PBMCs (monocytes, CD4+, CD8+, and NK cells) preferentially adhered and transmigrated in a cytokine priming-dependent manner. These PBMCs released clinically relevant IBD cytokines and biomarkers and induced barrier disruption, a hallmark of IBD. Anti-TNF-α antibodies and AJM300 caused reduced PBMC recruitment, inflammatory response and barrier disruption &gt;90%. Dexamethasone had more modest effects, as expected.

Conclusion
The human Colon Intestine-Chip can both model complex immune cell-driven IBD and validate effects of clinically relevant IBD drugs. This system could provide predictive validity for pre-clinical development of new IBD drugs.
Investigating DAGLβ expression and activity in human monocytes via proteomic and lipidomic profiling
Authors: Murtagh Olivia , McSorley Caitlin , Hsu Ku-Lung 
Published: August 2023

Abstract
Lipid-metabolizing enzymes are important targets for small-molecule inhibitor discovery as the regulation of inflammation responses have been linked to lipid metabolism cascades controlled by these enzymes. Non-steroidal anti-inflammatory drugs inhibit enzymes in the COX pathway preventing conversion of arachidonic acid (AA) into inflammation-inducing prostaglandins. An upstream precursor to AA is the endocannabinoid 2-arachidonoyl-glycerol (2-AG), which is biosynthesized from the cleavage of arachidonate-containing diacylglycerols (DAGs) by diacylglycerol lipase beta (DAGLβ). Previous work to identify DAGLβ’s role in inflammatory function led to the creation of KT109, a DAGLβ-specific 1,2,3-triazole urea inhibitor. Primary mouse macrophages treated with KT109 showed reductions in AA and 2-AG and an increase in arachidonate-containing DAGs, demonstrating that DAGLβ is key in proinflammatory lipid regulation and signaling. These studies focused on the effects of inhibiting mouse DAGLβ, but information regarding KT109 inhibition of human DAGLβ is still lacking. Herein, we applied activity-based protein profiling (ABPP) and quantitative proteomic and lipidomic methods to determine the effectivity of KT109 inhibition in human monocytic cell line THP1. Potency (IC50 values) for DAGLβ inhibition by KT109 in human THP1 cells were comparable to the magnitude of inhibition in mouse cells. Lipidomic analysis of KT109-treated monocytic and macrophage-differentiated THP1s did not demonstrate an accumulation of arachidonate-containing DAGs. These findings show a potential difference in the expression and activity of human DAGLβ when compared to mouse DAGLβ and additional targets of KT109 in human cells.
Funding and disclosures: This work was supported by the National Institute on Drug Abuse grant no. R01 DA043571.
Open Chromatin: The Guide to Inflammatory Mediators in PCOS
Authors: Shabakesaz Pauniz , Banaszewska Beata , Duleba Antoni , Nicholas Dequina 
Published: August 2023

Abstract
Inflammation comorbid with insulin resistance and metabolic dysfunction are major manifestations of Polycystic Ovary Syndrome (PCOS). However, the type of inflammation associated with POCS and its effect remains uncharacterized making it important to identify inflammatory mediators that contribute to PCOS-related metabolic dysfunction. Our data from a mouse model of PCOS shows increased secretion of proinflammatory cytokines from Th17 cells. Th17 inflammation is associated with metabolic dysfunction in type 2 diabetes. Therefore, we hypothesize that Th17 cells predominate PCOS-specific inflammation. We will test this hypothesis using peripheral blood mononuclear cells (PBMCs) collected from a prospective cohort of 20 fully clinically characterized Polish women: 15 with PCOS and 5 without. Combinations of cytokines and transcription factors, specific to different immune cell types, will have enhanced access to inflammation-related loci promoting transcription. We have used assay for transposase-accessible chromatin with sequencing (ATAC-Seq) of nuclei extracted from the PBMCs of our cohort to test whether chromatin loci important for Th17 cells are accessible as reflected by regions of open chromatin in immune cells of patients with PCOS. We expect our ATAC-seq data to distinguish women with PCOS from control by an open chromatin signature that represents distinct cytokine profiles and Th17 specific transcription factor binding sites. This is the first step to generating a multivariable map of inflammation in this metabolic disease, with the long-term objective being the development of targeted anti-inflammatory therapeutics for PCOS and comorbid insulin resistance.
NIH grant#3TR00HD09833004S1 from NICHD
NIH grant#5TR00HD09833004 from NICHD
Adenylate kinase 4 is critical to the function of classically activated macrophage
Authors: Miaw Shi-Chuen , Chin Wei-Yao 
Published: August 2023

Abstract
Macrophage plays a crucial role in the front line of host defense against pathogens. Classically activated macrophages (M1), induced by IFN-g and LPS, highly express inflammatory cytokines and contribute to inflammatory processes. By contrast, alternatively activated macrophages (M2) are induced by IL-4/IL-13, produce IL-10, and display anti-inflammatory activity. Adenylate kinase 4 (Ak4), an enzyme that transfers phosphate group among ATP/GTP, AMP, and ADP, is a key modulator of ATP. Ak4 is involved in maintaining the homeostasis of cellular nucleotides which is essential for cellular function. We observed Ak4 is preferentially expressed in M1 macrophages compared to M2 macrophages. Whether Ak4 is critical for M1 macrophage function remains elusive. Here we demonstrated that Ak4 maintained ATP homeostasis, and was critical for ROS production, glycolysis, and bactericidal ability in M1 macrophages. Moreover, Ak4 promoted the expression of inflammatory genes, including Il1b, Il6, Tnfa, Nos2, Nox2 and Hif1a, in M1 macrophages via Hif1a and AMPK. However, Ak4 deficiency did not affect the development of murine immune cells. Taken together, our data depict a potential mechanism linking nucleotide homeostasis and the function of M1 macrophage.
Taiwan Ministry of Science and Technology (111-2320-B-002-068-MY3)
Leukocyte and Lymphatic Interactions at the Cribriform Lymphatics
Authors: Laaker Collin , Sandor Matyas , Fabry Zsuzsanna 
Published: August 2023

Abstract
There is mounting evidence that the lymphatic vessels surrounding the central nervous system (CNS) play an important role in maintaining fluid homeostasis, antigen drainage, waste clearance, and steady-state immune cell migration from the CNS. Recently we reported in a murine mouse model of multiple sclerosis and stroke that during inflammatory brain disease a large number of dendritic cells (DCs) are recruited to the cribriform lymphatics, near the olfactory bulbs. These brain-derived DCs then bind to LECs at the cribriform plate (cp) and are retained at the vessel instead of trafficking straight to lymph nodes forming measurable DC-LEC aggregates. Here in this study, we attempted to characterize these DC-LEC interactions, to better understand the role of these binding events on neuroinflammatory disease. To accomplish this we performed a series of scRNAseq experiments which revealed that during neuroinflammation lymphatic endothelial cells at the cribriform plate up-regulate several factors related to leukocyte adhesion, antigen processing/presentation, and cytokine signaling. Additionally, scRNAseq data suggests that many of these DC-LEC interactions could be immunoregulatory in nature, modifying local immune cells population via the PD-L1/PD1 axis. Together our data suggest that the cribriform lymphatics represent an immunological niche where the inflammatory immune response is regulated.
Supported by grants from NIH 1R01NS126595-01A1
Bi-directional crosstalk between gut microbiota and NKT cells
Authors: Olkhanud Purevdorj B , Rodrigues Richard , Betrapally Naga , Bagheri Hana , Trinchieri Giorgio , Berzofsky Jay A 
Published: August 2023

Abstract
The gut microbiome interacts with the host, including local and systemic immunity. However, the causal mechanisms are relatively under-explored. In this study, we sought to identify bi-directional crosstalk between gut microbiota and type I and/or type II NKT cells using C57BL/6 WT (wild-type), Traj18-knock out (KO) (lacks only type I NKT cells), or CD1d-KO (lacks both type I and II NKT cells) mice. Mice were co-housed with each other strain in combination from the age of day 30 (9 days after weaning) for 30 days and housed separately again for another 30 days. Fecal pellets collected at the age of days 30, 60, and 90 were sequenced by 16S rRNA (250 bp paired-end, Illumina) sequencing, identifying 1,276 amplicon sequence variants (ASVs) by analysis (QIIME2). Microbes with low frequency (&lt;0.5%) or exhibiting cage effects within a strain at day 30 were filtered out. Comparing the microbial abundances between the different groups (co-housing or not) and time points revealed an interesting phenomenon regarding four ASVs (the closest known species was Muribaculum intestinale strain YL27 (16S pident 86.7–95.6)). They showed differential abundance (limma p-value &lt; 0.05) between strains at day 30 (e.g., an ASV_802 was most abundant in WT mice, then CD1-KO, and lowest in Traj18-KO mice). These closely related bacteria were not transferred to Traj18-KO mice when co-housed with WT or CD1-KO mice. Because the ASV is present in WT and CD1d KO mice, even though the latter also lack type I NKT cells as well as type II, our results suggest the existence of specific microbe(s) that cannot grow well in the presence of unopposed type II NKT cells.
Alterations in Germinal Center (GC) Formation and B Cell Activation during Severe Orientia tsutsugamushi Infection in Mice
Authors: Gonzales Casey A , Liang Yuejin , Thiriot Joseph , Sun Jiaren , Soong Lynn 
Published: August 2023

Abstract
Scrub typhus is a poorly studied, but life-threatening, disease caused by the bacterium Orientia tsutsugamushi (Ot). Humoral immunity in scrub typhus patients wanes as early as one-year post-infection; yet its underlying mechanisms remain unclear. The objective of this study is to delineate mechanisms underlying humoral immune dysregulation and B cell dysfunction during acute Ot infection. Using a lethal scrub typhus C57BL/6 murine model, we evaluated splenic GC responses by immunofluorescent staining. Splenic germinal centers (GL-7+ cells) were formed at D4, but were nearly absent at D8, accompanied by randomly scattered T cells. Both infection days had comparable numbers of GC B cells and T follicular helper (Tfh) cells, indicating that GC loss at D8 was less likely due to cell death, but rather dysregulation in GC formation. To confirm this hypothesis, we performed RNAseq analysis of purified B220+ B cells and revealed a set of differentially expressed genes associated with B cell adhesion (S1PR1, ICAM1, GPR183) and co-stimulation (CD40, ICOS-L, SLAMF1) at D8. Notably, the downregulation of S1PR2 (a GC-specific adhesion gene) was most evident at D8, correlating to disrupted GC formation. Furthermore, transcriptomic data revealed significant downregulation of 71% B cell activation genes on D8, suggesting attenuation of B cell activation. Additional studies with low- and high-virulence Ot strains and comparative flow cytometry revealed significant differences in both B cell subsets (plasmablasts, marginal zone B cells) and T cell subsets (Tfh and Tfr cells). This is the first study showing marked dysregulation of B cell responses during Ot infection, which helps understand the transient immunity associated with scrub typhus.
Supported by grants from NIH (R01 AI132674, R21 AI156536, R21 AI153586, R01 EY028773, T32 AI007526), Department of Defense Threat Reduction Agency grant (HDTRA1-19-1-0043), UTMB IHII Data Acquisition (CIRWH&IHII Pilot/ Phase II Research grant) and UTMB Center for Biodefense and Emerging Infectious Diseases (Pilot grant)
Host colonization with cutaneous commensal induces humoral immunity via formation of dermal tertiary lymphoid organs
Authors: Gribonika Inta , Perez-Chaparro Paula Juliana , Chi Liang , Veres Tibor , Germain Ronald , Belkaid Yasmine 
Published: August 2023

Abstract
The skin is one of the largest barrier sites which harbors a plethora of microorganisms. Whether skin microbiota promotes humoral responses remains unknown. Here we show that colonization with common skin commensal Staphylococcus epidermidis profoundly modulates cutaneous immunity that results in serum responsiveness with antigen-specific IgG antibodies. Such response is uncoupled from inflammatory signals and is associated with the induction of dermal tertiary lymphoid organs that closely resemble classical germinal centers. Of note, such responses occur in a tissue autonomous manner as evidenced by the preserved antibody repertoire in mice deficient in professional lymphoid organs. Our data also uncover a non-redundant role for Langerhan’s cells for the generation of commensal specific antibodies. Further, our work proposes a model by which commensal specific antigens are collected in the hair follicle leading to the generation of T follicular helper cells that further expand the local B cell pool in an IL-21-dependent manner. We also found that commensal induced antibodies can protect the host against subsequent infection with the same microbe demonstrating the importance of this line of defense in maintaining barrier protection. Collectively, our observations highlight the autonomous potential of skin organizational flexibility and for the first time demonstrate that B cells represent an indispensable local cutaneous compartment that actively maintains skin immunity.