bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perinatal androgen exposure impacts mast cell development and sex differences in mast cell-mediated pathophysiology
Authors: Moeser Adam James , Mackey Emily 
Published: January 2023

Abstract
Mast cell (MC)-associated diseases exhibit a sex bias with females often exhibiting more severe symptoms. Further, these sex biases exist in both prepubertal children and adults indicating that mechanisms other than adult sex hormones are involved. In previous studies, we showed that, compared with female MCs, male MCs store and release less histamine which coincided with reduced severity of MC-mediated anaphylaxis, and that these sex differences emerge prior to puberty. The early life mechanisms responsible for the emergence of sex differences in MC-associated disease remain poorly understood. Here we tested the hypothesis that perinatal androgen exposure, a major sexual organization event in males, drives sex differences in MC-mediated pathophysiology. Adult female mice that were previously exposed to high levels of androgens in the perinatal period (E16-PN7) via perinatal testosterone propionate administration had reduced IgE-mediated serum histamine levels and hypothermic responses compared with control females. In contrast, perinatal exposure of males to the endocrine disruptor DEHP, with known anti-androgenic effects, exacerbated IgE-mediated histamine levels and hypothermia. MC-deficient sash mice engrafted with BMMCs from adult perinatally androgenized females, exhibited reduced serum histamine and hypothermia responses compared with WT BMMC engrafted sash controls. Together, these data demonstrate that androgen exposure during the perinatal period shapes MC phenotype and MC-mediated anaphylaxis and thus could be an important determinant of differences in later life MC disease risk between the sexes.
Double Deletion of C5aR1 and C5aR2 during Streptococcal Pneumonia
Authors: Walachowski Sarah , Dudek Markus , Eshkind Leonid , Tansi Vanessa , Mizgerd Joseph P. , Bosmann Markus 
Published: January 2023

Abstract
The complement system is essential for the clearance of encapsulated bacteria such as Streptococcus pneumoniae (Spn), recognized as a major pathogen of pneumonia. Yet, it is not entirely clear whether C5 and its activation product C5a have beneficial or detrimental effects on the outcome of Spn infection. C5a binds to its two homologous C5a receptors (C5aR1 and C5aR2). The extent of functional overlap and role distribution between C5aR1 and C5aR2 remains enigmatic. A critical barrier to allow studies on the role distributions of C5aRs has been the absence of a mouse strain with dual deletion of both receptors - which are encoded as adjacent, linked genes on mouse chromosome 7.
CRISPR/Cas9 guided gene editing was combined with zygote/pronucleus microinjections in C57BL/6J mice to generate a C5aR1/C5aR2 double-knockout strain (C5aR1/2−/−). PCR-based screening and Sanger sequencing confirmed a 12.6 kB deletion of the coding regions of C5aR1 and C5aR2 of the new mouse strain, C57BL/6J-Del( 7C5ar2-C5ar1)1Bosm. Phenotyping of C5aR1/2−/− mice was followed by functional studies including intra-tracheal injections of recombinant mouse C5a or intranasal injections of Spn TIGR4. The airway influx of Ly6G+SiglecF- neutrophils by C5a was abrogated in C5aR1/2−/− mice. Surprisingly, the dual genetic absence of C5a receptors was associated with a higher build-up of neutrophil numbers in alveolar spaces after Spn TIGR4 infection. In a transcriptome-wide screen, FACS-sorted myeloid cells from infected lungs of double and single knockout mice were subjected to RNA-sequencing. Identifying novel differentially expressed genes in the C5aR1/2−/− mice during Spn infection will help to uncover potential synergisms and redundancies of C5aR1 and C5aR2.
Tspan2 is involved in anti-infectious immune responses and CNS autoimmunity
Authors: Scheu Stefanie , Ruland Christina , Lahl Katharina , Zimmer Andreas , Werner Hauke , Förster Irmgard , Sparwasser Tim , Alferink Judith 
Published: January 2023

Abstract
Tetraspanin proteins regulate critical cellular processes in CNS development and immune defence against pathogens. Through lateral association within membrane domains or binding of interaction partners these proteins are involved in pathogen recognition, proliferation and trafficking of immune cells, as well as cell differentiation and motility in the CNS. The tetraspanin family member Tspan2 was originally identified in oligodendrocyte lineage cells. It has been implicated in immunoregulation in the CNS as Tspan2−/− mice show increased microglia and astrocyte activation in the absence of inflammatory stimuli.
A role of Tspan2 in CNS inflammation and anti-infectious immune responses remains to be elucidated. In newly generated Tspan2/DTR/EGFP reporter mice, we detected Tspan2 expression predominantly in mature oligodendrocytes in the CNS and an enhanced clinical severity of experimental autoimmune encephalomyelitis upon immunization with MOG35–55 peptide in Tspan2−/− mice. In peripheral lymphoid organs, Tspan2 expression was found in neutrophils and the majority of dendritic cells (DCs). Tspan2−/− DCs showed reduced uptake of zymosan as compared to wild-type (WT) DCs indicating that Tspan2 affects fungal recognition by DCs. In the absence of Tspan2 neutrophils exhibited a reduced accumulation of reactive oxygen species (ROS) and enhanced migration to inflammatory sites in thioglycollate-induced peritonitis as compared to WT neutrophils. LPS challenge in vivo induced increased production of the proinflammatory cytokines TNF, IL-1β, and IL-6 in the spleens of Tspan2−/− as compared to WT mice. These data provide first evidence that Tspan2 regulates anti-infectious immune responses as well as CNS autoimmunity.
Psychological stress creates an immune-suppressive environment that increases the susceptibility of aged mice to Mycobacterium tuberculosis infection
Authors: Lafuse William P , Wu Qian , Saljoughian Noushin , Turner Joanne , Rajaram Murugesan 
Published: January 2023

Abstract
Age is a risk factor for chronic infections, including tuberculosis (TB). A second compounding factor of TB susceptibility is psychological stress, which is particularly acute in older individuals. While the influence of psychological stress in TB is well documented, the mechanisms by which stress influences M.tb susceptibility in the elderly are almost completely unknown. To study the effects of chronic psychological stress on M.tb infection in old mice, we employed a mouse social stressor model (called social disruption stress or SDR) which involves repeated social defeat in subordinate mice. Young (3 month) and old (18 month) C57BL/6 mice were subjected to SDR and bronchial fluid (BF) and alveolar macrophages (AMs) were isolated by lung lavage. Our studies showed that SDR created an immune-suppressive lung environment in old mice, based on lower levels of pro-inflammatory cytokines and chemokines in bronchial fluid (BF) or their mRNA expression by AMs. AMs from old SDR mice compared to non-stressed mice were also deficient in their ability to mount an inflammatory cytokine response or induce MHC class II mRNA expression. To determine the effect of SDR on M.tb growth, young and old mice were subjected to SDR and infected with M.tb. At 30 days, SDR in both young and old mice reduced M.tb burden. However, this was transient as at 60 days M.tb burden was higher in old mice compared to young mice and SDR further significantly increased M.tb burden in old mice. Also we found that SDR at 60 days in old mice induced significantly higher levels of IL-10 and IL-17 mRNA in the lung, which favors growth of M.tb. In conclusion, our studies suggest that psychological stress during the initial stage of Mtb infection has long-term impact on the control of the infection.
Neutrophil recruitment and dysregulation in an intradermal murine model of Orientia tsutsugamushi Infection
Authors: Liang Yuejin , Sun Jiaren , Soong Lynn 
Published: January 2023

Abstract
Scrub typhus is a life-threatening zoonosis caused by Orientia tsutsugamushi organisms that are transmitted by the larvae of trombiculid mites. However, the reason that innate immune cells fail to control local infection is unknown. By using a newly established intradermal (i.d.) infection mouse model, we analyzed myeloid cell subpopulations in the inoculation site at 4 hours post-infection (hpi) and found significant recruitment of neutrophils, langerhans cells and Ly6chi monocytes in the skin. To investigate what type of cells can be infected, we i.d. challenged mice with CFSE-labeled bacteria. We found that the majority of infected cells at 4 hpi were neutrophils and monocytes, which comprised around 90% of all the CFSE+ cells. To determine the fates of these immune cells carrying Orientia, we examined CFSE+ cells in various organs at 24 hpi. Our flow cytometry data demonstrated that langerhans cells were the only infected cell subset that migrated to draining lymph nodes (dLN) but were not found in the blood, spleen, bone marrow or lungs at this early stage. There were very few infected neutrophils in either the skin or dLN at 24 hpi, indicating that bacterial challenge may promote neutrophil death. To confirm this result, we infected bone marrow-derived neutrophils and monitored cell death for 36 h. Our data showed that Orientia infection increased neutrophil death from 12 to 36 hpi. Interestingly, infected neutrophils displayed an immunosuppressive phenotype, as evidenced by decreased TNF-a, CXCL10 and ICAM-1, but increased arginase-1, CCL2 and IL-4. Collectively, our data suggest that Orientia-triggered neutrophil dysregulation and death may contribute to bacterial dissemination and systemic infection in scrub typhus.
IFN-β and IL-10 induce mTOR phosphorylation and regulate IFN-γ-induced autophagy during mycobacterial infection
Authors: Teles Rosane M.B. , Tran Thanh , Ochoa Maria T , Sarno Euzenir N , Modlin Robert L 
Published: January 2023

Abstract
The ability of mycobacteria to block the antimicrobial activity through the IFN-β→IL-10 pathway is critical to suppress IFN-γ induced antimicrobial response and increase mycobacterial survival. Leprosy is an infectious disease, caused by Mycobacterium leprae and IFN-γ is prevalent in the self-limited tuberculoid (T-lep) and reversal reaction (RR) lesions, whereas, IFN-β is higher in the disseminated lepromatous (L-lep) lesions. Here we investigated the role of the IFN-β→IL-10 pathway in the regulation of the IFN-γ-induced autophagy in M. leprae-infected macrophages. IFN-γ induced 65% more colocalization of the autophagosome with M. leprae compared to media alone. IFN-β and IL-10 reduced by 60% of the colocalization of LC3 and M. leprae induced by IFN-γ. The blocking of IL-10 recovered in 70% of the IFN-γ-induced autophagosomal fusion. Autophagy is negatively regulated by the mTOR complex 1 activation and live M. leprae induced phosphorylation of mTOR in 40% compared to uninfected MDMs. IFN-γ decreased the mTOR phosphorylation in 50% compared to media alone in M. leprae-infected MDMs. IL-10 reversed in 50% the IFN-γ-inhibition of mTOR phosphorylation in M. leprae infected macrophages. The colocalization of LC3 and M. leprae PGL-1 is higher in T-lep and RR in comparison with L-lep patients. However, mTOR phosphorylation was strongly detected in L-lep lesions vs. T-lep/RR lesions. The ability of the IFN-β → IL-10 pathway to inhibit IFN-γ-induced autophagy through induction of mTOR phosphorylation can be key for mycobacterial surveillance and inhibition of antigen presentation leading to disease pathogenesis.
The inhibition of the particulate matter-induced intrinsic apoptosis through metal-chelating in MLE-12 cells
Authors: Kim H.J. , Herath KHINM , Jeon You-Jin , Jee Youngheun , Kim Hyun Jung 
Published: January 2023

Abstract
Particulate matter containing transition metals has known to cause adverse health impacts. Reactive oxygen species (ROS) are overproduced by Fenton reaction of transition metal ions and occur to oxidative DNA damage with the induction of intrinsic apoptosis. Sargassum horneri, a brown alga, is one of rich sources for health functional compounds which can chelate transition metals. In this study, the inhibition of the PM-induced intrinsic apoptosis pathway by S. horneri ethanol extract (SHE) through metal-chelating in MLE-12 cells was investigated. When MLE-12 cells were exposed to PM, the titanium and iron contents were 1.05 and 4.55 Wt.%, respectively. However, after the SHE treatment at 125 μg/mL, they were significantly reduced to 0.35 and 0.02 Wt.%. Additionally, the reduction of iron concentration was observed at 62.5 μg/mL of SHE treatment which revealed the metal-chelating effect of SHE. The expressions of P53, Bax, Cytochrome-c, and cleaved caspase-3 involved in the intrinsic apoptosis were activated in MLE-12 after PM exposure and they were decreased by the SHE treatment at 62.5 and 125 μg/mL. On the other hand, the expression of caspase-8 related to the extrinsic apoptosis was not cleaved by PM exposure in MLE-12, which meant PM induced only intrinsic cell death. These results suggested that SHE can inhibit the PM-induced intrinsic apoptosis through metal-chelating in MLE-12.
Funded by the Ministry of Oceans and Fisheries, Republic of Korea (Project NO. 20172085).
A trichlorobenzene-substituted azaaryl compound MTP0L145 blocks endosomal acidification to inhibit dengue virus infection
Authors: Lin Chiou-Feng 
Published: January 2023

Abstract
Blocking endosomal acidification retards dengue virus (DENV) infection. A trichlorobenzene-substituted azaaryl compound MTP0L145, originally designed as a novel fibroblast growth factor receptor (FGFR) inhibitor, confers an unexpected inhibition on endosomal acidification. Here, we examined for the blockade of DENV infection by MTP0L145. As similar to Bafilomycin A1, treatment of FGFR inhibitors MTP0L145 and BGJ39 all cause a blocking effect on endosomal acidification in cells with DENV infection. Inhibiting FGFR significantly causes inhibition on DENV infection, including dsRNA replication, protein expression, and virus release, but not viral entry as well as translation directly. FGFR antagonist NSC12, a blocker of FGF and FGFR interaction, neither inhibits viral entry nor causes blocking effects on endosomal acidification and viral replication, indicating a ligand-independent involvement. MTP0L145 and BGJ-398 inhibit receptor tyrosine kinase activity in FGFRs following DENV infection. Activation of vacuolar-type H+-ATPase for endosomal activation requires FGFR-mediated PI3-kinase/Akt and MAPK activation. Inhibiting the FGFR signaling pathway effectively retards DENV infection and mortality. These results demonstrate that MTP0L145 treatment reduces DENV infection principally by retarding FGFR-regulated endosomal acidification.
This study was supported by grants from the Ministry of Science and Technology (MOST108-2320-B-038-026), Taipei, Taiwan.
Differential innate immune response based on surgical treatment strategy after multiple trauma
Authors: Lackner Ina , Weber Birte , Gebhard Florian , Pfeifer Roman , Cinelli Paolo , Teuben Michel , Halvachizadeh Sascha , Lipiski Miriam , Cesarovic Nikola , Huber-Lang Markus , Pape Hans-Christoph , Kalbitz Miriam 
Published: January 2023

Abstract

Background
The complement system is part of the innate immunity, is activated immediately after trauma and is associated with ARDS, MOF and with death of multiply injured patients. The aim of the study was to investigate the complement activation in multiply injured pigs as well as its effects on the heart in vivo and in vitro. Moreover, the impact of reamed vs. non-reamed intramedullary nailing was examined with regard to the complement activation.

Methods
Male pigs received multiple trauma (blunt chest trauma, liver laceration, femur fracture, hemorrhagic shock), followed by femoral nailing with/without prior conventional reaming. Systemic complement hemolytic activity as well as the local cardiac expression of complement receptors was determined in vivo after trauma. Human cardiomyocytes were exposed to C3a or C5a and analyzed regarding calcium signaling and mitochondrial respiration.

Results
Systemic complement activation increased within 6h after trauma and was mediated via the classical and the alternative pathway. The expression of receptors for complement activation were altered locally in vivoin left ventricles. C3a and C5a acted detrimentally on human cardiomyocytes in vitro.

Conclusion
After multiple trauma, an early activation of the complement system is triggered, affecting the heart in vivo as well as in vitro, leading to complement-induced cardiac dysfunction. The intensity of complement activation after multiple trauma correlated with the invasiveness of fracture treatment. Consequently, the choice of fracture treatment might imply the clinical outcome of the critically injured patients and might be therefore crucial for their survival.
The Role of Dendritic Cells in Clostridium difficile Infection
Authors: Sun Xingmin , Wang Yuankai , kim Hyeun Bum , Zhuge Ronghua 
Published: January 2023

Abstract
C. difficile colonization and toxin production can lead to a wide range of symptoms from diarrhea to pseudomembranous colitis, systemic disease and death. The host immune status plays an important role in protection against C. difficile infection (CDI), especially the dendritic cells (DCs) as a bridge to connect innate and adaptive immunity. However, their role during CDI has not been characterized. In this study, we adopted a murine model of transgenic mice Tg-CD11c-DTR/EGFP (Tg), whose DCs can be conditionally depleted by injection of diphtheria toxin (DT), to investigate the role of DCs in CDI. We found that DT-injected Tg mice were more vulnerable to the CDI, compared with the PBS-injected Tg mice. DT-injection significantly depleted DCs, impaired the host capability to clear off C. difficile in the intestine, and increased the infiltration of other bacteria into organs. DC deletion did not seem to affect intestinal microbiota, nor neutrophil infiltration into lumen, but reduced macrophage infiltration into intestinal lumen. Interestingly, DC depletion impaired the intestinal barrier integrity, which could partially contribute to the increased infiltration of intestinal bacteria to organs, and severity of CDI. Transferring DCs to wild-type mice conferred host resistance to CDI. These data clearly demonstrate a protective role of DCs against CDI.
E3 Ubiquitin Ligase Nedd4 Is Essential for Anti-fungal Innate Immune Response
Authors: Nuro-Gyina Patrick Kwadwo , Guo Hui , Tang Na , Zhang Jian 
Published: January 2023

Abstract
C. albicans is the most common cause of fungal infections in humans, and disseminated candidiasis has become one of the leading causes of hospital-acquired blood stream infections with 45% to 75% mortality rate. The understanding of the host–pathogen interactions and the mechanisms of antifungal immunity is critical for developing immune-based strategies to combat candidemia. Nedd4 is a HECT-type E3 ubiquitin ligase which has been shown to positively regulate T cell activation and proliferation. However, the role of Nedd4 in innate immunity is unknown. To elucidate the role of Nedd4 in innate immune response against fungal infection, we generated Nedd4f/fRosa26-Cre-ERT2 and LysMCre.Nedd4f/f mice which lack Nedd4 systemically and in myeloid cells respectively. We found that although Nedd4 does not regulate the signalling via TLRs, it is required for the signalling through Dectin-1 and Dectin-2, two major fungal recognition receptors. Nedd4f/fRosa26-Cre-ERT2 and LysMCre.Nedd4f/f mice are highly susceptible to systemic C. albicans infection, which correlates with heightened organ fungal burden, defective inflammatory response, impaired leukocyte recruitment to the kidneys, and defective ROS expression by the granulocytes. At the molecular levels, Nedd4−/− macrophages from mice display impaired activation of NF-kB, p38, and ERK, but normal activation of Syk and PKC-d upon C. albicans yeast and hyphal infections. These data suggest that Nedd4 regulates the signaling event upstream of NF-kB/MAPK but downstream of PKC-d. Our data suggest Nedd4 expression in the myeloid cells is crucial for CLR-mediated innate immune response against systemic C. albicans infection.
A reparative neutrophil population released post-injury, increases host susceptibility to infection
Authors: Thanabalasuriar Ajitha , Keller Ashley , Cohen Taylor , DiGiandomenico Antonio 
Published: January 2023

Abstract
Patients suffering from severe thermal injury are susceptible to opportunistic infections, with pneumonia serving as the primary manifestation. The underlying mechanisms contributing to burn-induced infection susceptibility remains poorly understood. Using a combination of intravital microscopy, flow cytometry and a murine thermal injury infection model, we elucidate a novel population of neutrophils. Following injury, a population of neutrophils are released from the bone marrow and immediately travel to the lung where they appear trapped within the lung vasculature. These neutrophils express CD47, PDL-1, Cxcr4, and Cd11a suggesting that they are a unique ‘reparative’ subset. Consistent with this hypothesis, a significant number of these neutrophils migrated to injured tissue by 48h, correlating with wound healing. Interestingly, susceptibility to Pseudomonas aeruginosa lethal pneumonia was directly linked to neutrophil accumulation in the lung up to 24h post-injury. During this period, neutrophils were observed to phagocytose bacteria but were incapable of containing the infection. Intriguingly treatment with PDL-1 or TGFB neutralizing antibody, causes neutrophils to traffic directly to the skin without being stuck in the lungs. This alleviates susceptibility to infection but results in poor healing outcomes in the skin. In conclusion, we provide evidence that burn-injury promotes an imbalance in neutrophil subsets, which contributes to increased susceptibility to lung infection.
Rack1 is essential for activation of the Nlrp3 inflammasome
Authors: He Yuan , Duan Yanhui , Zhang Lingzhi , Nunez Gabriel , Kelley Nathan 
Published: January 2023

Abstract
The NLRP3 inflammasome is a critical component of the innate immune system that activates caspase-1 to induce secretion of pro-inflammatory cytokines interleukin (IL)-1β/IL-18 and cell death in response to microbial infection and cellular damage. However, aberrant activation of the NLRP3 inflammasome contributes to the pathogenesis of several inflammatory disorders, including cryopyrin-associated periodic syndromes, Alzheimer’s disease, type 2 diabetes, and atherosclerosis. Although extensively investigated, the mechanism of NLRP3 inflammasome activation remains not fully understood. Here we used a proteomic approach to identify Nlrp3-interacting proteins in mouse macrophages and found that Rack1 (Receptor for activated C-kinase 1) interacts with both Nlrp3 and Nek7. Inhibition of Rack1 expression abrogated caspase-1 activation and IL-1β release in response to Nlrp3 stimuli, but not Nlrc4 or Aim2 stimuli. Furthermore, this function of Rack1 was independent of its ribosomal association. Mechanistically, Rack1 was required for Nlrp3-mediated Asc speck formation and Nlrp3 stimuli-induced inflammasome complex assembly. Our work therefore identifies Rack1 as a potential therapeutic target for treating NLRP3 inflammasome-driven inflammatory diseases. Given the fact that Rack1 is a critical component of plant innate R protein complexes and contributes to the host defense against rice blast infection, our work further highlights a conserved link in innate immunity between mammals and plants.