bluuebunny/crossref_metadata_2025_split huggingface dataset:
TRIM29 suppresses the innate immune response to RNA virus
Authors: Xing Junji , Zhang Ao , Minze Laurie J. , Li Xian Chang , Zhang Zhiqiang 
Published: January 2023

Abstract
The innate immunity is critically important in protection against virus infections, and in the case of RNA viral infections, the signaling mechanisms that initiate robust protective innate immunity without triggering autoimmune inflammation remain incompletely defined. We have previously found that TRIM29 is constitutively expressed in alveolar macrophages and plays a critical role in the control of innate immunity in respiratory tract. Also, we have shown that TRIM29 is highly expressed in human airway epithelial cells and promotes DNA virus infections by inhibiting innate immune response. Here, we found the E3 ligase TRIM29 was specifically expressed in poly I:C stimulated human myeloid dendritic cells (mDCs). The induced TRIM29 played a negative role in type I interferon (IFN) production in response to poly I:C or dsRNA virus reovirus infection. Importantly, the challenge of wildtype mice with reovirus led to lethal infection. In contrast, deletion of TRIM29 protected the mice from this developing lethality. Additionally, TRIM29−/− mice have lower titers of reovirus in the heart, intestine, spleen, liver, and brain due to elevated production of type I IFN. Mechanistically, TRIM29 was shown to interact with MAVS and subsequently induce its K11-linked ubiquitination and degradation. Taken together, TRIM29 regulates negatively the host innate immune response to RNA virus, which could be employed by RNA viruses for immune evasion.
Identification and strategic targeting of key anti-viral defense mechanisms in Natural Killer cells
Authors: Sayitoglu Ece Canan , Ozkazanc Didem , Sarac Aydan , Parlar Ayhan , Alici Evren , Erman Batu , Duru Adil Doganay , Sutlu Tolga 
Published: January 2023

Abstract
While genetic modification of lymphocytes proves to be an efficient approach in immunotherapy, commonly used lentiviral vectors are haunted by the activity of intrinsic restriction factors in immune cells. Natural Killer (NK) cells are members of the innate immune system that possess strikingly high resistance to viral infections, presenting a challenge to virus-based gene delivery methods. In this study, high-throughput analytical approaches were used for comprehensive characterization of NK cell anti-viral defense mechanisms resulting in the observed resistance of NK cells to lentiviral infections. Using Genome-scale CRISPR Knock-Out (GeCKO) Libraries and RNA sequencing, we show that the RLR and TLR pathways are major players influencing the dynamics of lentiviral gene delivery in NK-92 cells. More specifically, even though viral vectors can efficiently enter the cells, activation of anti-viral signaling pathways lead to intracellular elimination of the virus. Additionally, viral vector exposure increases MAPK activity in NK cells, specifically p38 and JNK phosphorylation, similar to the observations in HIV infections. To further confirm the involvement of RLR and TLR pathways, we performed targeted knock-out of 20 candidate genes, using CRISPR/Cas9 technology. Most importantly, our results demonstrate that dsRNA-induced signaling through RIG-I and TRIM25 in NK-92 cells is the key pathway restricting lentiviral gene delivery and small molecule inhibitors can help modulate key pathways. Our findings provide important insights for developing genetically modified NK cell-based immunotherapy approaches and also potentiate new targets to combat viral infections.
DUSP4 regulates STING- and RIG-I-mediated signalling in response to virus infection
Authors: Zhang Yongliang , Jiao Huipeng , James Sharmy J. 
Published: January 2023

Abstract
MAPK phosphatase (MKPs), also known as dual-specificity phosphatases (DUSPs), are cysteine-based protein tyrosine phosphatases that dephosphorylate phosphotyrosine, phosphothreonine, and phosphoserine residues in their substrates. They are originally identified as the major negative regulators of MAP kinases (MAPKs). Our recent study on DUSP10/MKP5 demonstrated that this molecule plays an important role in immune response to virus infection via dephosphorylating IRF3. DUSP4/MKP2 is another DUSP/MKP family member whose function in immune response to virus infection is unclear. This study aims to elucidate the regulatory function of DUSP4 in STING- and RIG-I-mediated signaling and in innate immune response to virus infection. We found that this protein is constitutively expressed in immune cells such as macrophages and its expression is increased in response to the activation of RIG-I and STING as well as virus infection including influenza and HSV. Studies using cells and mice deficient in DUSP4/MKP2 demonstrate that this molecule inhibits STING- and RIG-I-mediated signaling, thereby inhibiting the expression of proinflammatory cytokines including IL-6 and TNFa as well as type I interferon such as IFNb. Furthermore, DUSP4 deficient mice developed less severe diseases upon influenza and HSV infection, but more severe disease upon malaria parasite infection. Our studies demonstrate a novel function of DUSP4 in immune response to microbial infection and may be further explored for therapeutic purposes.
PAMP-induced monoubiquitination of PRR-associated kinase BIK1 by an E3 ligase LUCKY positively regulates plant innate immunity
Authors: Ma Xiyu , Peng Junmin , Shan Libo , He Ping 
Published: January 2023

Abstract
Innate immune responses are initiated by recognition of pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs) in both animals and plants. In animal, perception of bacteria flagellin by TLR5 transduces signal through MyD88-IRAK1-IRAK4 to ubiquitin E3 ligase TRAF6. TRAF6 coordinates with UBC13 to produce K63-linked polyubiquitination chains serving as scaffold to mediate downstream signaling. In plant, flagellin is recognized by receptor-like kinase FLS2 and co-receptor BAK1. Upon flagellin perception, BAK1 directly phosphorylates an IRAK-like cytoplasmic kinase BIK1, leading to BIK1 dissociation from the FLS2-BAK1 complex to relay signal. How BIK1 activation is regulated and how it transduces signal to downstream remain largely elusive. We report here that flagellin perception triggers rapid monoubiquitination of BIK1 in planta. Time course and mutational analysis suggested that flagellin-induced BIK1 phosphorylation precedes its monoubiquitination. Using a yeast-two-hybrid screen we identified a RING type E3 ligase LUCKY that interacts with BIK1 and monoubiquitinates multiple residues of BIK1. Mass spectrometry analysis of in vitro-ubiquitinated BIK1 revealed nine lysine residues and the BIK19KR mutant with all nine lysine-to-arginine substitutions blocked flagellin-triggered BIK1 ubiquitination. Transgenic complementation assays indicated that BIK19KR was unable to execute normal BIK1 functions. Moreover, we found that monoubiquitination of BIK1 controls ligand-induced BIK1 dissociation from receptor FLS2. Our study revealed that the ligand-induced monoubiquitination of a key PRR complex component positively regulates innate immunity.
Amifostine activates Nrf2 by binding to Keap1, suppressing lung inflammation
Authors: Joo Myungsoo 
Published: January 2023

Abstract
Although intracellular reactive oxygen species (ROS) produced during phagocytosis function as a key arsenal for innate immunity, inordinate production of ROS is detrimental to host cells, exacerbating inflammation. Nrf2/Keap1 axis is a key countering measure against ROS. Keap1 senses ROS via its thiols, resulting in Nrf2 activation and subsequent production of enzymes that nullify ROS. Amifostine is a cytoprotective thiophosphate that scavenges intracellular free radicals by donating hydrogen ions. Therefore, we tested whether amifostine can be used to suppress inflammation that involves intracellular ROS. Our results show that amifostine down-regulated the production of intracellular ROS induced by LPS. Interestingly, amifostine activated Nrf2 and suppressed the ubiquitination of Nrf2. Amifostine bound to Keap1 at S273, suggesting that amifostine suppresses the ubiquitination of Nrf2 by forming a complex with Keap1, which results in Nrf2 activation. In an LPS-induced acute lung injury mouse model, amifostine suppressed neutrophilic lung inflammation with decreased production of prototypic pro-inflammatory cytokines. Amifostine ameliorated lung damage and protected mice from LPS-induced sepsis. Together, our findings suggest that along with directly scavenging ROS, amifostine contributes to suppressing inflammation by activating Nrf2.
Defensamide, a new synthetic compound, could regulate epidermal innate immunity by stimulating cathelicidin antimicrobial peptide production
Authors: Mann Shivtaj , Park Kyungho 
Published: January 2023

Abstract
Sphingosine-1- phosphate (S1P), a signaling sphingolipid, has multiple biological functions, including stimulation of cathelicidin antimicrobial peptide (CAMP), an innate immune element. Recently, we described production of CAMP in human epidermal keratinocytes via a novel S1P→NF-κB-dependent mechanism. The catalytic activity of Sphingosine kinase (SPHK)-1 is widely described in literature to be essential in the production of S1P. In this study, we investigate whether defensamide, a new synthetically derived compound, can modulate the innate epidermal immune response by potentiating SPHK1 activity and inducing CAMP production. In cultured keratinocytes, treatment with defensamide (100uM) increased CAMP mRNA and protein expression, whereas blockade of SPHK1 by treatment of siRNA significantly attenuated defensamide-induced CAMP expression. Exogenous defensamide increased SPHK1 activity and cellular S1P levels but it did not alter the activity of S1P lyase, the key enzyme responsible for S1P degradation. Defensamide treatment also activated NF-κB which was assessed by nuclear translocation of NF-κB. Conversely, pretreatment with a specific inhibitor of SPHK1 attenuated defensamide-induced nuclear translocation of NF-κB. Accordingly, blockade of NF-κB activation with a specific inhibitor also attenuated defensamide-mediated increase in CAMP expression. Taken together, our results show the following: 1) defensamide induces CAMP production, and 2) induction of CAMP is likely via defensamide → SPHK1 activation → increased cellular S1P levels → NF-κB activation. These results highlight a potential role of defensamide in modulating innate epidermal antimicrobial defense by upregulating CAMP production.
Identification of Trim29 as a Key checkpoint inhibitor of natural killer cell functions
Authors: Dou Yaling , Xing Junji , Li Xianchang , Zhang Zhiqiang 
Published: January 2023

Abstract
Natural killer (NK) cells play an important role in immune surveillance and protective immunity, mainly through rapid cytokine release and cytolytic activities. But how such responses are regulated remains poorly defined. Here, we demonstrated that E3 ubiquitin ligase Trim29 is a crucial regulator of NK cell functions. NK cells lacking Trim29 show increased production of IFN-γ. NK cell-derived IFN-γ has previously been demonstrated to be protective against murine cytomegalovirus (MCMV) infection, and we show here that Trim29−/− mice as well as Trim29lox/loxNKp46-iCre mice exhibit decreased hepatic viral load upon challenge with MCMV, indicating that Trim29 acts within NK cells to regulate antiviral responses. In addition, we discovered that Trim29 is up-regulated in activated NK cells during MCMV infection in response to signals from the proinflammatory cytokines IL-12 and IL-18. Mechanistically, Trim29 suppresses NK cell IFN-γ expression by ubiquitinating the TGF-β activated kinase 1 binding protein 2 (TAB2). These results identify TRIM29 as a previously unknown regulator that restricts NK cell functions.
Gasdermin D exerts anti-inflammatory effects by promoting neutrophil death
Authors: Kambara Hiroto , Liu Fei , Zhang Xiaoyu , Liu Peng , Bajrami Besnik , Teng Yan , Zhao Li , Zhou Shiyi , Yu Hongbo , Zhou Weidong , Silberstein Leslie E. , Cheng Tao , Han Mingzhe , Xu Yuanfu , Luo Hongbo R. 
Published: January 2023

Abstract
Gasdermin D (GSDMD) is considered a pro-inflammatory factor that mediates pyroptosis in macrophages to protect hosts from intracellular bacteria. Here we reveal that GSDMD deficiency paradoxically augmented host responses to extracellular Escherichia coli, mainly by delaying neutrophil death, establishing GSDMD as a negative regulator of innate immunity. In contrast to its activation in macrophages, in which activated inflammatory caspases cleave GSDMD to produce an N-terminal fragment (GSDMD-cNT) to trigger pyroptosis, GSDMD cleavage and activation in neutrophils was caspase independent. It was mediated by a neutrophil-specific serine protease, neutrophil elastase (ELANE), released from cytoplasmic granules into the cytosol in aging neutrophils. ELANE-mediated GSDMD cleavage was upstream of the caspase cleavage site and produced a fully active ELANE-derived N-terminal fragment (GSDMD-eNT) that induced lytic cell death as efficiently as GSDMD-cNT. Thus, GSDMD is pleiotropic, exerting both pro- and anti-inflammatory effects that make it a potential target for anti-bacterial and anti-inflammatory therapies.
LincRNA-EPS and lincRNA-Cox2 regulate expression of KC, IL-6 and CCL5 in macrophages and mice treated with TLR2 and TLR4 agonists or during K. pneumoniae infection, but are dispensable for endotoxin tolerance
Authors: Agliano Federica , Karlinsey Keaton , Carpenter Susan , Medvedev Andrei E. 
Published: January 2023

Abstract
Long non-coding RNAs (lncRNAs) are critical regulators of immune responses, but their role in sepsis is largely unknown. During sepsis, TLR sensing of microbes triggers the “cytokines storm”, disseminated intravascular coagulation and organ damage. Patients surviving systemic inflammatory response syndrome develop profound immunosuppression that resembles TLR tolerance and often succumb to secondary infections. To study the sepsis-associated “cytokine storm”, we used in vivo exposure of mice to LPS (endotoxemia) and Pam3Cys, while endotoxin tolerization of macrophages in vitro was employed to examine features of sepsis-associated immunosuppression. This study showed that LPS-treated macrophages decreased expression of lincRNA-EPS while upregulating lincRNA-Cox2 levels. Using knockout mice, we demonstrated that lincRNA-EPS acts to restrain KC, IL6 and CCL5 expression in the serum, spleen, lungs and liver of LPS or Pam3Cys-treated mice. Infection of lincRNA-EPS−/− macrophages with Klebsiella pneumoniae led to increased expression of IL-6 and CCL5 compared to wild-type cells. K. pneumoniae-infected wild-type and lincRNA-EPS−/− macrophages exhibited similar levels of TNF-α and bacterial 16S RNA. Compared to wild-type animals, pulmonary K. pneumoniae infection of lincRNA-EPS−/− mice resulted in higher levels of serum and lung IL-6 but decreased lung TNF-α. Finally, we showed that lincRNA-EPS and lincRNA-Cox2 are not required for LPS tolerance induction in macrophages. Thus, lincRNA-EPS and lincRNA-Cox2 shape macrophage-elicited cytokine induction upon exposure to microbial agonists and regulate host responses to K. pneumoniae.
Phosphatase PTEN-mediated blockade of IL-2 production is essential for Th17 cell differentiation
Authors: Kim Hyeong Su , Sohn Hyogon , Lee Gap Ryol 
Published: January 2023

Abstract
T helper 17 (Th17) cells are one of CD4+ T cell subsets that mediate inflammation and autoimmunity. Unlike other subsets, interleukin 2 (IL-2) inhibits differentiation of Th17 cells but the mechanism that regulates Th17 differentiation is poorly understood. Here, we show that phosphatase and tensin homologue (PTEN) plays key role in Th17 cell differentiation by regulating IL-2 expression. We generated Th17-specific Pten knock-out mice (Pten fl/fl Il17a CRE) to investigate intrinsic role of PTEN. Th17-specific Pten deletion inhibited Th17 differentiation by inducing excessive expression of IL-2 in vitro. Over-expressed IL-2 recognized by IL-2 receptor and induced phosphorylation of STAT5, eventually triggered Foxp3 expression in Th17 cells. Next, we used experimental autoimmune encephalomyelitis (EAE) as in vivo model, Th17-specific deficiency of Pten ameliorated symptoms of EAE. Additionally, we used SF1670 which is PTEN-specific inhibitor for therapeutic approach. Treatment of SF1670 to EAE induced mice showed ameliorated symptoms of EAE, therefore PTEN may be a potential therapeutic target for Th17-mediated diseases.
Orally administered poly-γ-glutamic acid enhances mucosal immune responses through production of intestinal chemokines and activation of mucosal dendritic cells
Authors: Yang Jihyun , Kim Eunjin , Kim Jaemoo , Poo Haryoung 
Published: January 2023

Abstract
The oral administration of poly-gamma glutamic acid (γ-PGA), a safe and edible biomaterial naturally secreted by Bacillus subtilis sups. Chungkookjang, has been reported to enhance the anti-tumor immunity. After the oral uptake of γ-PGA, the underlying mechanism to affect the mucosal and systemic immune responses has not been displayed yet. Thus we checked the mucosal immune response induced by γ-PGA, such as the production of intestinal chemokines and the activation of mucosal dendritic cells. Upon oral administration of γ-PGA in mice, the presence of γ-PGA was observed in subepithelial dome region of peyer’s patch (PP). Orally administered γ-PGA enhanced levels of various chemokines in intestines, activation of DCs in PPs and accumulation of CD8− DC subsets in mesenteric lymph nodes. Oral administration of γ-PGA mixed with ovalbumin (OVA) as a model antigen increased activation of OVA-specific T cells and levels of both intestinal IgA and sera IgG compared with mice received OVA alone. Moreover, the γ-PGA-OVA group robustly suppressed tumor growth and increased survival in a murine cancer model seeded with the B16mOVA cells, which are B16 expressing membrane-bound OVA, compared to the OVA group. Taken together, these results suggest that γ-PGA induce the mucosal immune responses by enhancing the production of intestinal chemokines and the activation of mucosal dendritic cells, which lead to the increase of the anti-tumor immunity.
Lymphotoxin receptor beta expression by neutrophils is a critical regulator of colitis pathogenesis
Authors: Giles Daniel A. , Zahner Sonja Petra , van der Gracht Esmé , Morris Venetia , Tumanov Alexei , Mikulski Zbigniew , Kronenberg Mitchell 
Published: January 2023

Abstract
Inflammatory bowel disease, while multifactorial, is largely characterized by an exacerbated intestinal immune activation. However, the critical mechanisms regulating immune activation remain to be fully defined. We have previously reported that a member of the TNF superfamily, TNFSF14/LIGHT, is required for prevention of severe disease in a mouse model of dextran sodium sulfate (DSS) induced colitis. Additionally, antibody-mediated blocking of lymphotoxin beta receptor (LTβR), which recognizes LIGHT, also led to exacerbated colitis pathogenesis. Thus, we aimed to determine the cell type(s) and mechanism critical to LTβR mediated exacerbation of DSS driven colitis. Employing the use of LTβRflox/flox mice and appropriate Cre strains, we were able to evaluate the role of LTβR signaling during DSS-induced colitis in a variety of immune and intestinal cell types. For all experiments, body weight, colon length and intestinal histopathology were assessed. These studies revealed that neutrophils were the critical LTβR expressing cell type and that specific deletion of neutrophil LTβR expression, via MRP8 Cre, resulted in exacerbated DSS-induced colitis similar to that in LIGHT−/− mice. RNASeq analysis of neutrophils revealed alterations in cellular metabolism and mitochondrial function, further confirmed through ex vivo analysis of LTβR deficient neutrophils, which had increased mitochondria. In sum, our results demonstrate that neutrophil LTβR activation, likely through LIGHT signaling, plays a critical role in the immune activation associated with DSS-induced colitis.
Targeting fatty acid amide hydrolase (FAAH) in diffuse large B-cell lymphoma (DLBCL).
Authors: Woods Christian Tyler Rutan , Sun Jeff , Henderson Jared , Mohan Chandra 
Published: January 2023

Abstract

Background
DLBCL is an aggressive disease and the most common type of non-Hodgkin lymphoma among adults. Endocannabinoids have been shown to produce anti-proliferative and pro-apoptotic actions in a broad spectrum of tumors. FAAH is the primary enzyme responsible for regulating levels of endocannabinoids. Here we explore the role of FAAH inhibition in DLBCL.

Methods
Western blot analysis was used to probe for FAAH expression in the human DLBCL cell lines, U2392 and Ly-7. The apoptotic effect of an FAAH inhibitor (URB 597) was tested. Next, DLBCL was co-treated with URB 597 and an endocannabinoid (AEA) to simulate endocannabinoid accumulation in cancer tissues. Cellular apoptosis rates were measured by Annexin V and Caspase 3/7 staining and flow cytometry.

Results
High levels of FAAH were observed in both DLBCL cell lines. AEA alone induced significant apoptosis over vehicle control in a dose dependent manner. The greatest change was observed at 30 μm AEA treatment, which resulted in a 9.8 fold increase in apoptosis rate (p&lt;0.001). Together with URB597, AEA increased DLBCL death dramatically in a supra-additive manner. The most significant change was observed at co-treatment levels of 10 μM URB597 and 30 μM AEA, which resulted in a 16.8 fold increase (p&lt;0.001) in apoptosis rate compared to vehicle control.

Conclusions
FAAH inhibition is a promising approach to induce cell death in DLBCL tumors. Studies are in progress to test the in vivo efficacy of FAAH inhibition and the underlying pathogenic mechanisms.
Distinct innate immune responses to different murine mammary carcinoma are evident within the first 72 hours of tumor injection
Authors: Kurt Robert A. , Zhang Chenyu , schwartz Jennifer , Newsom-Stewart Catherine , Baranovic Alison , Chilel-Martin Silvia 
Published: January 2023

Abstract
We used three different murine mammary carcinoma, each syngeneic in Balb/c mice, to study the early anti-tumor immune response. Initial analysis showed that the number of cells at the tumor sites almost doubled between 12–72 hours going from about 3e5 cells at 12 hours to about 6e5 cells at 72 hours. Surface staining revealed that the immune response during this time period was predominated by Gr1+ and F4/80+ cells. Strikingly, similar cell numbers and cell types were recruited to saline injected sites suggesting that these cells may be recruited non-specifically. However, closer examination revealed significant differences not only between the saline and tumor injected sites, but also among different tumor sites. For instance, at 12 hours post injection there were significantly more Gr1+ cells at the EMT6 tumor site than at the 4T1 tumor site, and at 48 hours there were significantly more Gr1+ cells at the 168 tumor site than at the saline and 4T1 tumor sites. At 24 hours post injection there were significantly more F4/80+ cells at the EMT6 tumor site than at the 4T1, 168 and saline injected sites, and at 72 hours post injection there were significantly more F4/80+ cells at the EMT6 tumor site compared to the 4T1 and 168 tumor sites. Next, we collected the Gr1+ and F4/80+ cells from the sites 24 hours after tumor delivery and using qRT-PCR we found several additional differences. For instance, the Gr1+ cells from the EMT6 tumor site expressed more arginase and less CCL2 than the Gr1+ cells from the 4T1 and 168 tumor sites, and the F4/80+ cells from the EMT6 site expressed more MMP-9 and TNF-a than F4/80+ cells from the 4T1 and 168 tumor sites. Collectively, these data indicated that a unique anti-tumor immune response was evident within hours of tumor delivery.