B-cell-specific checkpoint molecules that regulate anti-tumour immunity

The role of B cells in anti-tumour immunity is still debated and,accordingly,immunotherapies have focused on targeting T and natural killer cells to inhibit tumour growth1,2.Here,using high-throughput flow cytometry as well as bulk and single-cell RNA-sequencing and B-cell-receptor-sequencing analysis of B cells temporally during B16F10 melanoma growth,we identified a subset of B cells that expands specifically in the draining lymph node over time in tumour-bearing mice.The expanding B cell subset expresses the cell surface molecule T cell immunoglobulin and mucin domain 1(TIM-1,encoded by Havcr1)and a unique transcriptional signature,including multiple co-inhibitory molecules such as PD-1,TIM-3,TIGIT and LAG-3.Although conditional deletion of these co-inhibitory molecules on B cells had little or no effect on tumour burden,selective deletion of Havcr1 in B cells both substantially inhibited tumour growth and enhanced effector T cell responses.Loss of TIM-1 enhanced the type 1 interferon response in B cells,which augmented B cell activation and increased antigen presentation and co-stimulation,resulting in increased expansion of tumour-specific effector T cells.Our results demonstrate that manipulation of TIM-1-expressing B cells enables engagement of the second arm of adaptive immunity to promote anti-tumour immunity and inhibit tumour growth.

The role of innate immunity in diabetic nephropathy and their therapeutic consequences

Diabetic nephropathy (DN) is an enduring condition that leads to inflammation and affects a substantial number of individuals with diabetes worldwide. A gradual reduction in glomerular filtration and emergence of proteins in the urine are typical aspects of DN, ultimately resulting in renal failure. Mounting evidence suggests that immunological and inflammatory factors are crucial for the development of DN. Therefore, the activation of innate immunity by resident renal and immune cells is critical for initiating and perpetuating inflammation. Toll-like receptors (TLRs) are an important group of receptors that identify patterns and activate immune responses and inflammation. Meanwhile, inflammatory responses in the liver, pancreatic islets, and kidneys involve inflammasomes and chemokines that generate pro-inflammatory cytokines. Moreover, the activation of the complement cascade can be triggered by glycated proteins. This review highlights recent findings elucidating how the innate immune system contributes to tissue fibrosis and organ dysfunction, ultimately leading to renal failure. This review also discusses innovative approaches that can be utilized to modulate the innate immune responses in DN for therapeutic purposes.

m^(1)A inhibition fuels oncolytic virus-elicited antitumor immunity via downregulating MYC/PD-L1 signaling

N^(1)-methyladenosine(m^(1)A)RNA methylation is critical for regulating mRNA translation;however,its role in the development,progression,and immunotherapy response of head and neck squamous cell carcinoma(HNSCC)remains largely unknown.Using Tgfbr1 and Pten conditional knockout(2cKO)mice,we found the neoplastic transformation of oral mucosa was accompanied by increased m^(1)A modification levels.Analysis of m^(1)A-associated genes identified TRMT61A as a key m^(1)A writer linked to cancer progression and poor prognosis.Mechanistically,TRMT61A-mediated tRNA-m^(1)A modification promotes MYC protein synthesis,upregulating programmed death-ligand 1(PD-L1)expression.Moreover,m^(1)A modification levels were also elevated in tumors treated with oncolytic herpes simplex virus(oHSV),contributing to reactive PD-L1 upregulation.Therapeutic m^(1)A inhibition sustained oHSV-induced antitumor immunity and reduced tumor growth,representing a promising strategy to alleviate resistance.These findings indicate that m^(1)A inhibition can prevent immune escape after oHSV therapy by reducing PD-L1 expression,providing a mutually reinforcing combination immunotherapy approach.

Impact of exercise on markers of B cell-related immunity:A systematic review

Background:B cells represent a crucial component of adaptive immunity that ensures long-term protection from infection by generating pathogen-specific immunoglobulins.Exercise alters B cell counts and immunoglobulin levels,but evidence-based conclusions on potential benefits for adaptive immunity are lacking.This systematic review assessed current literatures on the impact of acute exercise and exercise training on B cells,immunoglobulins,and markers of secretory immunity in human biofluids.Methods:According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,MEDLINE,Web of Science,and Embase were searched on March 8,2023.Non-randomized controlled trials and crossover trials investigating the impact of acute exercise or exercise training on B cell counts and proportions,immunoglobulin levels,salivary flow rate,or secretory immunoglobulin A secretion rate were included.Quality and reporting of exercise training studies were assessed using the Tool for the Assessment of Study Quality and reporting in Exercise.Study characteristics,outcome measures,and statistically significant changes were summarized tabularly.Results:Of the 67 eligible studies,22 applied acute exercise and 45 applied exercise training.All included outcomes revealed significant alterations over time in acute exercise and exercise training context,but only a few investigations showed significant differences compared to control conditions.Secretory and plasma immunoglobulin A levels were most consistently increased in response to exercise training.Conclusion:B cell-related outcomes are altered by acute exercise and exercise training,but evidence-based conclusions cannot be drawn with high confidence due to the large heterogeneity in populations and exercise modalities.Well-designed trials with large sample sizes are needed to clarify how exercise shapes B cell-related immunity.

Herb pair of Huangqi-Danggui exerts anti-tumor immunity to breast cancer by upregulating PIK3R1

Background:According to traditional Chinese medicine(TCM),drugs supplementing the vital energy,Qi,can eliminate tumors by restoring host immunity.The objective of this study is to investigate the underlying immune mechanisms of anti-tumor activity associated with Qi-supplementing herbs,specifically the paired use of Huangqi and Danggui.Methods:Analysis of compatibility regularity was conducted to screen the combination of Qi-supplementing TCMs.Using the MTT assay and a transplanted tumor mice model,the anti-tumor effects of combination TCMs were investigated in vitro and in vivo.High content analysis and flow cytometry were then used to evaluate cellular immunity,followed by network pharmacology and molecular docking to dissect the significant active compounds and potential mechanisms.Finally,the anti-tumor activity and the mechanism of the active ingredients were verified by molecular experiments.Results:There is an optimal combination of Huangqi and Danggui that,administered as an aqueous extract,can activate immunity to suppress tumor and is more effective than each drug on its own in vitro and in vivo.Based on network pharmacology analysis,PIK3R1 is the core target for the anti-tumor immunity activity of combined Huangqi and Danggui.Molecular docking analysis shows 6 components of the combined Danggui and Huangqi extract(quercetin,jaranol,isorhamnetin,kaempferol,calycosin,and suchilactone)that bind to PIK3R1.Jaranol is the most important component against breast cancer.The suchilactone/jaranol combination and,especially,the suchilactone/kaempferol combination are key for immunity enhancement and the anti-tumor effects of the extract.Conclusions:The combination of Huangqi and Danggui can activate immunity to suppress breast cancer and is more effective than the individual drugs alone.

The life-history trait trade-offs mediated by reproduction and immunity in the brown planthopper,Nilaparvata lugens Stål

Reproduction and immune defense are costly functions,and they are expected to tradeoff with each other to drive evolution.The brown planthopper(BPH),Nilaparvata lugens Stål(Hemiptera,Delphacidae),is a global superpest that mostly damages rice crops.Yeast-like symbionts(YLS)exist in the abdominal fat body tissue and are tightly associated with the development,growth,and reproduction of BPH.Our previous research demonstrated that mating behavior promotes the release of YLS from the fat body into the hemolymph in the BPH,thereby triggering an immune response.Additionally,the fitness costs related to life-history traits of BPH(such as survival rate)have a strong dependence on the relative abundance of YLS.However,the possible relationship between reproduction and the immune response in BPH has not been identified.In this study,an omics-based approach was used to analyze the transcriptome of fat body tissues in mated and unmated BPH at 72 h post-eclosion,from which two antimicrobial peptide genes,NlDefensin A(NlDfA)and NlDefensin B(NlDfB),were selected since they were highly expressed in mated BPH.Subsequently,the full-length cDNA sequences of the NlDfA and NlDfB genes were cloned and analyzed.qPCR results showed up-regulation of the NlDfA and NlDfB genes in mated BPH when compared to unmated BPH.Spatial-temporal expression analysis indicated that the NlDfA and NlDfB genes were expressed in all tissues and developmental stages,and they were most highly expressed in the fat body at 24 h post-eclosion.Moreover,the symbionts in BPH were significantly inhibited by the in vitro expression of the NlDfA and NlDfB proteins.Furthermore,RNA interference(RNAi)-mediated suppression of NlDfA and NlDfB dramatically increased the relative abundance of YLS in the fat body,while YLS in the hemolymph decreased significantly.These BPHs also displayed some fitness disadvantages in survival,fecundity,hatchability,and possibly the vertical transmission of YLS from hemolymph to egg.Our results indicated that mating could heighten the immunity of BPH by upregulating the expression of the NlDfA and NlDfB genes,which protect the host from pathogen challenges during reproduction.However,the reduced content of YLS may act as a fitness disadvantage in dictating the life-history traits of BPH.This work has significant theoretical and practical implications for the precise green control technology that involves crucial gene targeting,as well as for the“endosymbionts for pest control”strategy in insects.

Pharmacological Investigation on the Qi-Invigorating Action of Schisandrin B: Effects on Mitochondrial ATP Generation in Multiple Tissues and Innate/Adaptive Immunity in Mice

Schisandrae Fructus, containing schisandrin B (Sch B) as its main active component, is recognized in traditional Chinese medicine (TCM) for its Qi-invigorating properties in the five visceral organs. Our laboratory has shown that the Qi-invigorating action of Chinese tonifying herbs is linked to increased mitochondrial ATP generation and an enhancement in mitochondrial glutathione redox status. To explore whether Sch B can exert Qi-invigorating actions across various tissues, we investigated the effects of Sch B treatment on mitochondrial ATP generation and glutathione redox status in multiple mouse tissues ex vivo. In line with TCM theory, which posits that Zheng Qi generation relies on the Qi function of the visceral organs, we also examined Sch B’s impact on natural killer cell activity and antigen-induced splenocyte proliferation, both serving as indirect measures of Zheng Qi. Our findings revealed that Sch B treatment consistently enhanced mitochondrial ATP generation and improved mitochondrial glutathione redox status in mouse tissues. This boost in mitochondrial function was associated with stimulated innate and adaptive immune responses, marked by increased natural killer cell activity and antigen-induced T/B cell proliferation, potentially through the increased generation of Zheng Qi.

Effects of antioxidant‑rich Lactiplantibacillus plantarum inoculated alfalfa silage on rumen fermentation, antioxidant and immunity status, and mammary gland gene expression in dairy goats

Background Milk synthesis in lactating animals demands high energy metabolism,which results in an increased production of reactive oxygen metabolites(ROM)causing an imbalance between oxidants and antioxidants thereby inducing oxidative stress(OS)on the animals.To mitigate OS and postpartum disorders in dairy goats and gain insight into the impact of dietary choices on redox status during lactation,a feeding trial was conducted using alfalfa silage inoculated with a high-antioxidant strain of Lactiplantibacillus plantarum.Methods Twenty-four Guanzhong dairy goats(38.1±1.20 kg)were randomly assigned to two dietary treatments:one containing silage inoculated with L.plantarum MTD/1(RSMTD-1),and the other containing silage inoculated with high antioxidant activity L.plantarum 24-7(ES24-7).Results ES24-7-inoculated silage exhibited better fermentation quality and antioxidant activity compared to RSMTD-1.The ES24-7 diet elevated the total antioxidant capacity(T-AOC),superoxide dismutase(SOD),glutathione peroxi-dase(GSH-Px),and catalase(CAT)activities in milk,serum,and feces of lactating goats(with the exception of T-AOC in milk).Additionally,the diet containing ES24-7 inoculated silage enhanced casein yield,milk free fatty acid(FFA)content,and vitamin A level in the goats’milk.Furthermore,an increase of immunoglobulin(Ig)A,IgG,IgM,inter-leukin(IL)-4,and IL-10 concentrations were observed,coupled with a reduction in IL-1β,IL-2,IL-6,interferon(IFN)-γ,and tumor necrosis factor(TNF)-αconcentrations in the serum of lactating goats fed ES24-7.Higher concentrations of total volatile fatty acid(VFA),acetate,and propionate were observed in the rumen fluid of dairy goats fed ES24-7 inoculated silage.Moreover,the diet containing ES24-7 inoculated silage significantly upregulated the expression of nuclear factor erythroid 2 like 2(NFE2L2),beta-carotene oxygenase 1(BCO1),SOD1,SOD2,SOD3,GPX2,CAT,glu-tathione-disulfide reductase(GSR),and heme oxygenase 1(HMOX1)genes in the mammary gland,while decreased the levels of NADPH oxidase 4(NOX4),TNF,and interferon gamma(IFNG).Conclusions These findings indicated that feeding L.plantarum 24-7 inoculated alfalfa silage not only improved rumen fermentation and milk quality in lactating dairy goats but also boosted their immunity and antioxidant status by modulating the expression of several genes related to antioxidant and inflammation in the mammary gland.

A novel chorismate mutase effector secreted from root-knot nematode Meloidogyne enterolobii manipulates plant immunity to promote parasitism

Meloidogyne spp.is an economically important plant-parasitic nematode distributed worldwide.To fight with host immune system for successful parasitism,plant parasitic nematodes secrete effectors to promote infection.In this study,we identified one chorismate mutase(CM)effector from M.enterolobii,named Me-CM.Spatial and temporal expression assays exhibited Me-cm is expressed in esophageal glands and up-regulated at parasitic-stage juveniles.Me-CM affects the pathogenicity of M.enterolobii based on the reduced infection rate,number of galls,egg masses,eggs per mass and multiplication rate collected from RNA silencing experiments.We showed that Me-CM localized in the cytoplasm and nucleus of plant cells and decreased the expression level of the marker gene PR1 of salicylic acid(SA)pathway.Besides,constitutive expression of Me-cm in Arabidopsis thaliana significantly reduced salicylic acid concentration.These results suggested that M.enterolobii may secrete effector Me-CM to fight with plantimmunesystemsvia regulating SA signaling pathway when interacting with host plants,ultimately facilitating parasitism.

Does Herd Immunity Reduce the Risk of Contracting COVID-19?

Herd immunity is often considered a measure to protect a whole community or population from disease if the vaccination threshold is met. Using the demographic and COVID-19 infection data from the state of Pennsylvania, United States, the study aimed to determine if herd immunity by vaccination is an effective way to reduce the spread of the COVID-19 virus. The Pennsylvania counties were split into two groups based on qualification of herd immunity: counties that met the COVID-19 herd immunization rate of 70% and counties that did not. The ANOVA test was used to analyze the difference between the groups with and without herd immunity by the COVID-19 vaccine. The results demonstrated that there was no significant statistical difference between counties that did achieve and those that did not achieve the herd immunity threshold for the COVID-19 vaccine. On the other hand, it was observed that there had been a significant decrease in positive cases between 2020 and 2023. This decline can be attributed to the overall protection by the vaccination and adaptability to the disease, not specifically due to herd immunity alone. Ultimately, these outcomes suggest that herd immunity cannot reduce the risk of contracting COVID-19. Increased efforts to get vaccinated should be implemented to protect the general community and a wider scope of age.

Targeting the chromatin structural changes of antitumor immunity

Epigenomic imbalance drives abnormal transcriptional processes,promoting the onset and progression of cancer.Although defective gene regulation generally affects carcinogenesis and tumor suppression networks,tumor immunogenicity and immune cells involved in antitumor responses may also be affected by epigenomic changes,which may have significant implications for the development and application of epigenetic therapy,cancer immunotherapy,and their combinations.Herein,we focus on the impact of epigenetic regulation on tumor immune cell function and the role of key abnormal epigenetic processes,DNA methylation,histone post-translational modification,and chromatin structure in tumor immunogenicity,and introduce these epigenetic research methods.We emphasize the value of small-molecule inhibitors of epigenetic modulators in enhancing antitumor immune responses and discuss the challenges of developing treatment plans that combine epigenetic therapy and immuno-therapy through the complex interaction between cancer epigenetics and cancer immunology.

Harnessing immunity:Immunomodulatory therapies in COVID-19

An overly exuberant immune response,characterized by a cytokine storm and uncontrolled inflammation,has been identified as a significant driver of severe coronavirus disease 2019(COVID-19)cases.Consequently,deciphering the intricacies of immune dysregulation in COVID-19 is imperative to identify specific targets for intervention and modulation.With these delicate dynamics in mind,immunomodulatory therapies have emerged as a promising avenue for miti-gating the challenges posed by COVID-19.Precision in manipulating immune pathways presents an opportunity to alter the host response,optimizing antiviral defenses while curbing deleterious inflammation.This review article compre-hensively analyzes immunomodulatory interventions in managing COVID-19.We explore diverse approaches to mitigating the hyperactive immune response and its impact,from corticosteroids and non-steroidal drugs to targeted biologics,including anti-viral drugs,cytokine inhibitors,JAK inhibitors,convalescent plasma,monoclonal antibodies(mAbs)to severe acute respiratory syndrome coronavirus 2,cell-based therapies(i.e.,CAR T,etc.).By summarizing the current evidence,we aim to provide a clear roadmap for clinicians and researchers navigating the complex landscape of immunomodulation in COVID-19 treatment.CS Glucocorticoids are among the most widely prescribed drugs with their immune-suppressive and anti-inflammatory effect[84].The current guidelines for the treatment of COVID-19 recommend against the use of dexamethasone or other systemic CS in non-hospitalized patients in the absence of another indication[70].The RECOVERY trial demonstrates the reduced 28-d mortality among hospitalized patients with COVID-19 using dexamethasone compared to the usual standard of care,along with other investigators,such as Ahmed and Hassan[85].The benefit of dexamethasone was seen only among participants receiving either oxygen alone or invasive mechanical ventilation at randomization but not among those receiving no respiratory support at enrollment[85].In a systematic review and meta-analysis,Albuquerque et al[86]showed that in comparison to tocilizumab,baricitinib,and sarilumab are associated with high probabilities of similar mortality reductions among hospitalized COVID-19 concurrently treated with CS.As a result of the absence of SARS-CoV-2-specific antiviral medications,the effectiveness of COVID-19 treatments is reduced.Several COVID-19 therapies are now under investigation.However,the majority of them lack specificity,efficacy,and safety[87].Immunotherapy is a ground-breaking medical treatment that manipulates the immune system to fight diseases.Translational research is rapidly progressing,recognized as a significant breakthrough in 2013[88].Among the immunotherapeutic options for treating COVID-19 are Immunoglobulin,CP,antibodies,mAbs(mAbs),NK cells,T cells,TLR,cytokine therapies and immune modulators.

The Magnaporthe oryzae effector Avr-PikD suppresses rice immunity by inhibiting an LSD1-like transcriptional activator

Avirulence effectors(Avrs),encoded by plant pathogens,can be recognized by plants harboring the corresponding resistance proteins,thereby initiating effector-triggered immunity(ETI).In susceptible plants,however,Avrs can function as effectors,facilitating infection via effector-triggered susceptibility(ETS).Mechanisms of Avr-mediated ETS remain largely unexplored.Here we report that the Magnaporthe oryzae effector Avr-PikD enters rice cells via the canonical cytoplasmic secretion pathway and suppresses rice basal defense.Avr-PikD interacts with an LSD1-like transcriptional activator AKIP30 of rice,and AKIP30 is also a positive regulator of rice immunity,whereas Avr-PikD impedes its nuclear localization and suppresses its transcriptional activity.In summary,M.oryzae delivers Avr-PikD into rice cells to facilitate ETS by inhibiting AKIP30-mediated transcriptional regulation of immune response against M.oryzae.

Tumor-infiltrating T-Lymphocyte immunity-related immune tolerance and anti–programmed cell death protein 1/ligand of programmed cell death protein 1 therapy for advanced hepatocellular carcinoma

Systemic therapy has become the standard treatment for patients with advanced hepatocellular carcinoma(HCC)whose treatment options are limited.However,the long-term patient response to drugs and the survival outcomes remain a concern.With increasing exploration of the HCC microenvironment,particularly in terms of T lymphocyte immunity,a new era of immunomolecular targeted therapy,based on molecular signaling,has arrived for advanced HCC.In the study of immune tolerance of the intrinsic HCC microenvironment,we found that multiple immunosuppressive mechanisms and immune checkpoint inhibitors,such as anti–programmed cell death protein 1/ligand of programmed cell death protein 1 therapy,have improved clinical outcomes in some patients with advanced HCC.Furthermore,various combination therapies have been investigated,and HCC types have been categorized into different types based on anti–programmed cell death protein 1(PD-1)/ligand of programmed cell death protein 1(PD-L1)treatment.In this paper,we first discuss the tumor-infiltrating T lymphocyte immunity and immune tolerance of HCC.We then clarify the basic mechanism of anti–PD-1/PD-L1 therapy and discuss the types of HCC based on anti–PD-1/PD-L1 therapy.Thereafter,we explain the relevant studies and mechanisms of combination therapy of anti–PD-1/PD-L1 with antiangiogenesis drugs or multikinase kinase inhibitors,anti–T lymphocyte–related signaling pathways in HCC,and other anti-CD8+T cell immune checkpoints.In this way,this review offers a deeper understanding of anti–PD-1/PD-L1 immunotherapy for advanced HCC,in order to provide better individualized treatments for patients with advanced HCC.

OsbZIP53 Negatively Regulates Immunity Response by Involving in Reactive Oxygen Species and Salicylic Acid Metabolism in Rice

The basic region/leucine zipper(bZIP)transcription factors play important roles in plant development and responses to abiotic and biotic stresses.OsbZIP53 regulates resistance to Magnaporthe oryzae in rice by analyzing APIP5-RNAi transgenic plants.To further investigate the biological functions of OsbZIP53,we generated osbzip53 mutants using CRISPR/Cas9 editing and also constructed OsbZIP53 over-expression transgenic plants.Comprehensive analysis of phenotypical,physiological,and transcriptional data showed that knocking-out OsbZIP53 not only improved disease resistance by inducing a hypersensitivity response in plants,but also regulated the immune response through the salicylic acid pathway.Specifically,disrupting OsbZIP53 increased H2O2 accumulation by promoting reactive oxygen species generation through up-regulation of several respiratory burst oxidase homologs(Osrboh genes)and weakened H2O2 degradation by directly targeting OsMYBS1.In addition,the growth of osbzip53 mutants was seriously impaired,while OsbZIP53 over-expression lines displayed a similar phenotype to the wild type,suggesting that OsbZIP53 has a balancing effect on rice immune response and growth.

Impact of nutritional support on immunity,nutrition,inflammation,and outcomes in elderly gastric cancer patients after surgery

BACKGROUND Postoperative rehabilitation of elderly patients with gastric cancer has always been the focus of clinical attention.Whether the intervention by a full-course nutritional support team can have a positive impact on the postoperative immune function,nutritional status,inflammatory response,and clinical outcomes of this special population has not yet been fully verified.AIM To evaluate the impact of full-course nutritional support on postoperative comprehensive symptoms in elderly patients with gastric cancer.METHODS This is a retrospective study,including 60 elderly gastric cancer patients aged 70 years and above,divided into a nutritional support group and a control group.The nutritional support group received full postoperative nutritional support,including individualized meal formulation,and intravenous and parenteral nutrition supplementation,and was regularly evaluated and adjusted by a professional nutrition team.The control group received routine postoperative care.RESULTS After intervention,the proportion of CD4+lymphocytes(25.3%±3.1%vs 21.8%±2.9%,P<0.05)and the level of immunoglobulin G(12.5 G/L±2.3 G/L vs 10.2 G/L±1.8 G/L,P<0.01)were significantly higher in the nutritional support group than in the control group;the changes in body weight(-0.5 kg±0.8 kg vs-1.8 kg±0.9 kg,P<0.05)and body mass index(-0.2±0.3 vs-0.7±0.4,P<0.05)were less significant in the nutritional support group than in the control group;and the level of C-reactive protein(1.2 mg/L±0.4 mg/L vs 2.5 mg/L±0.6 mg/L,P<0.01)and WBC count(7.2×10^(9)/L±1.5×10^(9)/L vs 9.8×10^(9)/L±2.0×10^(9)/L,P<0.01)were significantly lower in the nutritional support group than in the control group.In addition,patients in the nutritional support group had a shorter hospital stay(10.3 d±2.1 d vs 14.8 d±3.6 d,P<0.05)and lower incidence of infection(15%vs 35%,P<0.05)in those of the control group.CONCLUSION The intervention by the nutritional support team has a positive impact on postoperative immune function,nutritional status,inflammatory response,and clinical outcomes in elderly patients with gastric cancer.

Pepper mild mottle virus coat protein interacts with pepper chloroplast outer envelope membrane protein OMP24 to inhibit antiviral immunity in plants

Pepper mild mottle virus(PMMoV)is a devastating viral pathogen of pepper(Capsicum annuum)but it is unclear whether and how peppers protect against PMMoV infection.The expression of the chloroplast outer membrane protein 24(OMP24)of C.annuum was upregulated under PMMoV infection and it interacted with PMMoV coat protein(CP).Silencing of OMP24 in either C.annuum or Nicotiana benthamiana facilitated PMMoV infection,whereas overexpression of N.benthamiana OMP24 in transgenic plants inhibited PMMoV infection.Both C.annuum OMP24(CaOMP24)and N.benthamiana OMP24(NbOMP24)localized to the chloroplast and have a moderately hydrophobic transmembrane domain that is necessary for their localization.Overexpression of CaOMP24 induced stromules,perinuclear chloroplast clustering,and accumulation of reactive oxygen species(ROS),the typical defense responses of chloroplasts transferring the retrograde signaling to the nucleus to regulate resistance genes.The expression of PR1 and PR2 was also upregulated significantly in plants overexpressing OMP24.Self-interaction of OMP24 was demonstrated and was required for OMP24-mediated plant defense.Interaction with PMMoV CP interfered with the self-interaction of OMP24 and impaired OMP24-induced stromules,perinuclear chloroplast clustering and ROS accumulation.The results demonstrate the defense function of OMP24 in pepper during viral infection and suggest a possible mechanism by which PMMoV CP modulates the plant defense to facilitate viral infection.

SlWRKY30 and SlWRKY81 synergistically modulate tomato immunity to Ralstonia solanacearum by directly regulating SlPR-STH2

Bacterial wilt is a devastating disease of tomato(Solanum lycopersicum)caused by Ralstonia solanacearum that severely threatens tomato production.Group III WRKY transcription factors(TFs)are implicated in the plant response to pathogen infection;however,their roles in the response of tomato to R.solanacearum infection(RSI)remain largely unexplored.Here,we report the crucial role of SlWRKY30,a group III SlWRKY TF,in the regulation of tomato response to RSI.SlWRKY30 was strongly induced by RSI.SlWRKY30 overexpression reduced tomato susceptibility to RSI,and also increased H2O2 accumulation and cell necrosis,suggesting that SlWRKY30 positively regulates tomato resistance to RSI.RNA sequencing and reverse transcription–quantitative PCR revealed that SlWRKY30 overexpression significantly upregulated pathogenesis-related protein(SlPR-STH2)genes SlPR-STH2a,SlPR-STH2b,SlPR-STH2c,and SlPR-STH2d(hereafter SlPR-STH2a/b/c/d)in tomato,and these SlPR-STH2 genes were directly targeted by SlWRKY30.Moreover,four group III WRKY proteins(SlWRKY52,SlWRKY59,SlWRKY80,and SlWRKY81)interacted with SlWRKY30,and SlWRKY81 silencing increased tomato susceptibility to RSI.Both SlWRKY30 and SlWRKY81 activated SlPR-STH2a/b/c/d expression by directly binding to their promoters.Taking these results together,SlWRKY30 and SlWRKY81 synergistically regulate resistance to RSI by activating SlPR-STH2a/b/c/d expression in tomato.Our results also highlight the potential of SlWRKY30 to improve tomato resistance to RSI via genetic manipulations.

Advances in viral encephalitis:Viral transmission,host immunity,and experimental animal models

Viral infections have led to many public health crises and pandemics in the last few centuries.Neurotropic virus infection-induced viral encephalitis(VE),especially the symptomatic inflammation of the meninges and brain parenchyma,has attracted growing attention due to its high mortality and disability rates.Understanding the infectious routes of neurotropic viruses and the mechanism underlying the host immune response is critical to reduce viral spread and improve antiviral therapy outcomes.In this review,we summarize the common categories of neurotropic viruses,viral transmission routes in the body,host immune responses,and experimental animal models used for VE study to gain a deeper understanding of recent progress in the pathogenic and immunological mechanisms under neurotropic viral infection.This review should provide valuable resources and perspectives on how to cope with pandemic infections.

Liver immunity,autoimmunity,and inborn errors of immunity

The liver is the front line organ of the immune system.The liver contains the largest collection of phagocytic cells in the body that detect both pathogens that enter through the gut and endogenously produced antigens.This is possible by the highly developed differentiation capacity of the liver immune system between self-antigens or non-self-antigens,such as food antigens or pathogens.As an immune active organ,the liver functions as a gatekeeping barrier from the outside world,and it can create a rapid and strong immune response,under unfavorable conditions.However,the liver's assumed immune status is anti-inflammatory or immuno-tolerant.Dynamic interactions between the numerous populations of immune cells in the liver are key for maintaining the delicate balance between immune screening and immune tolerance.The anatomical structure of the liver can facilitate the preparation of lymphocytes,modulate the immune response against hepatotropic pathogens,and contribute to some of its unique immunological properties,particularly its capacity to induce antigen-specific tolerance.Since liver sinusoidal endothelial cell is fenestrated and lacks a basement membrane,circulating lymphocytes can closely contact with antigens,displayed by endothelial cells,Kupffer cells,and dendritic cells while passing through the sinusoids.Loss of immune tolerance,leading to an autoaggressive immune response in the liver,if not controlled,can lead to the induction of autoimmune or autoinflammatory diseases.This review mentions the unique features of liver immunity,and dysregulated immune responses in patients with autoimmune liver diseases who have a close association with inborn errors of immunity have also been the emphases.