Interplay between creeping fat and gut microbiota: A brand-new perspective on fecal microbiota transplantation in Crohn's disease

Inflammatory bowel disease,particularly Crohn's disease(CD),has been linked to modifications in mesenteric adipose tissue(MAT)and the phenomenon known as"creeping fat"(CrF).The presence of CrF is believed to serve as a predictor for early clinical recurrence following surgical intervention in patients with CD.Notably,the incorporation of the mesentery during ileocolic resection for CD has been correlated with a decrease in surgical recurrence,indicating the significant role of MAT in the pathogenesis of CD.While numerous studies have indicated that dysbiosis of the gut microbiota is a critical factor in the development of CD,the functional implications of translocated microbiota within the MAT of CD patients remain ambiguous.This manuscript commentary discusses a recent basic research conducted by Wu et al.In their study,intestinal bacteria from individuals were transplanted into CD model mice,revealing that fecal microbiota trans-plantation(FMT)from healthy donors alleviated CD symptoms,whereas FMT from CD patients exacerbated these symptoms.Importantly,FMT was found to affect intestinal permeability,barrier function,and the levels of proinflammatory factors and adipokines.Collectively,these findings suggest that targeting MAT and CrF may hold therapeutic potential for patients with CD.However,the study did not evaluate the composition of the intestinal microbiota of the donors or the subsequent alterations in the gut microbiota.Overall,the gut microbiota plays a crucial role in the histopathology of CD,and thus,targeting MAT and CrF may represent a promising avenue for treatment in this patient population.

Exploring gut microbiota as a novel therapeutic target in Crohn’s disease: Insights and emerging strategies

Extensive research has investigated the etiology of Crohn’s disease(CD),encompassing genetic predisposition,lifestyle factors,and environmental triggers.Recently,the gut microbiome,recognized as the human body’s second-largest gene pool,has garnered significant attention for its crucial role in the patho-genesis of CD.This paper investigates the mechanisms underlying CD,focusing on the role of‘creeping fat’in disease progression and exploring emerging therapeutic strategies,including fecal microbiota transplantation,enteral nutri-tion,and therapeutic diets.Creeping fat has been identified as a unique patho-logical feature of CD and has recently been found to be associated with dysbiosis of the gut microbiome.We characterize this dysbiotic state by identi-fying key microbiome-bacteria,fungi,viruses,and archaea,and their contributions to CD pathogenesis.Additionally,this paper reviews contemporary therapies,empha-sizing the potential of biological therapies like fecal microbiota transplantation and dietary interventions.By elucidating the complex interactions between host-microbiome dynamics and CD pathology,this article aims to advance our under-standing of the disease and guide the development of more effective therapeutic strategies for managing CD.

Fecal microbiota transplantation in allergic diseases

Microorganisms such as bacteria,fungi,viruses,parasites living in the human intestine constitute the human intestinal microbiota.Dysbiosis refers to composi-tional and quantitative changes that negatively affect healthy gut microbiota.In recent years,with the demonstration that many diseases are associated with dysbiosis,treatment strategies targeting the correction of dysbiosis in the treat-ment of these diseases have begun to be investigated.Faecal microbiota trans-plantation(FMT)is the process of transferring faeces from a healthy donor to another recipient in order to restore the gut microbiota and provide a therapeutic benefit.FMT studies have gained popularity after probiotic,prebiotic,symbiotic studies in the treatment of dysbiosis and related diseases.FMT has emerged as a potential new therapy in the treatment of allergic diseases as it is associated with the maintenance of intestinal microbiota and immunological balance(T helper 1/T helper 2 cells)and thus suppression of allergic responses.In this article,the definition,application,safety and use of FMT in allergic diseases will be discussed with current data.

Gut microbiota shifts in hepatitis B-related portal hypertension after transjugular intrahepatic portosystemic shunt:Mechanistic and clinical implications

In this article,we provide commentary on the recent article by Zhao et al.We focus on the shifts in the gut microbiota of patients with hepatitis B virus(HBV)-associated cirrhosis/portal hypertension(PH)following transjugular intrahepatic portosystemic shunt(TIPS)and the implications for understanding the mechanisms,diagnosis,and treatment.By comparing the gut microbiota composition and dynamic changes before and after TIPS in patients with and without hepatic encephalopathy,the authors found an increase in non-probiotic bacteria in those who developed hepatic encephalopathy post-TIPS,with Morganella species present only in the hepatic encephalopathy group.The gut microbiota changes post-TIPS among patients without the occurrence of hepatic encephalopathy suggest potential therapeutic benefits through prophylactic microbiome therapies.Furthermore,the specific gut microbiota alterations may hold promise to predict the risk of hepatic encephalopathy in individuals undergoing TIPS for HBVrelated PH.Despite these promising findings,future studies are needed to address limitations,including a small sample size,a relatively short evaluation period for gut microbiota alterations,the absence of data on dynamic alterations in gut microbiota post-TIPS and their correlation with blood ammonia levels,and the lack of validation in animal models.In conclusion,Zhao et al's study has shed new light on the link of gut microbiota with post-TIPS hepatic encephalopathy,potentially through the intricate gut-liver axis,and has important clinical implications for improving the management of patients with HBV-related PH.

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various diseases.In recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus decrease.This dysbiosis may promote the formation and recurrence of polyps.Similar microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these conditions.Regulating the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut health.This microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

Creeping fat and gut microbiota in Crohn’s disease

In this article,we explored the role of adipose tissue,especially mesenteric adipose tissue and creeping fat,and its association with the gut microbiota in the pathophysiology and progression of Crohn’s disease(CD).CD is a form of inflammatory bowel disease characterized by chronic inflammation of the gastrointestinal tract,influenced by genetic predisposition,gut microbiota dysbiosis,and environmental factors.Gut microbiota plays a crucial role in modulating immune response and intestinal inflammation and is associated with the onset and progression of CD.Further,visceral adipose tissue,particularly creeping fat,a mesenteric adipose tissue characterized by hypertrophy and fibrosis,has been implicated in CD pathogenesis,inflammation,and fibrosis.The bacteria from the gut microbiota may translocate into mesenteric adipose tissue,contributing to the formation of creeping fat and influencing CD progression.Although creeping fat may be a protective barrier against bacterial invasion,its expansion can damage adjacent tissues,leading to complications.Modulating gut microbiota through interventions such as fecal microbiota transplantation,probiotics,and prebiotics has shown potential in managing CD.However,more research is needed to clarify the mechanisms linking gut dysbiosis,creeping fat,and CD progression and develop targeted therapies for microbiota modulation and fat-related complications in patients with CD.

Correlation between gut microbiota and tumor immune microenvironment:A bibliometric and visualized study

BACKGROUND In recent years,numerous reports have been published regarding the relationship between the gut microbiota and the tumor immune microenvironment(TIME).However,to date,no systematic study has been conducted on the relationship between gut microbiota and the TIME using bibliometric methods.AIM To describe the current global research status on the correlation between gut microbiota and the TIME,and to identify the most influential countries,research institutions,researchers,and research hotspots related to this topic.METHODS We searched for all literature related to gut microbiota and TIME published from January 1,2014,to May 28,2024,in the Web of Science Core Collection database.We then conducted a bibliometric analysis and created visual maps of the published literature on countries,institutions,authors,keywords,references,etc.,using CiteSpace(6.2R6),VOSviewer(1.6.20),and bibliometrics(based on R 4.3.2).RESULTS In total,491 documents were included,with a rapid increase in the number of publications starting in 2019.The country with the highest number of publications was China,followed by the United States.Germany has the highest number of citations in literature.From a centrality perspective,the United States has the highest influence in this field.The institutions with the highest number of publications were Shanghai Jiao Tong University and Zhejiang University.However,the institution with the most citations was the United States National Cancer Institute.Among authors,Professor Giorgio Trinchieri from the National Institutes of Health has the most local impact in this field.The most cited author was Fan XZ.The results of journal publications showed that the top three journals with the highest number of published papers were Frontiers in Immunology,Cancers,and Frontiers in Oncology.The three most frequently used keywords were gut microbiota,tumor microenvironment,and immunotherapy.CONCLUSION This study systematically elaborates on the research progress related to gut microbiota and TIME over the past decade.Research results indicate that the number of publications has rapidly increased since 2019,with research hotspots including“gut microbiota”,“tumor microenvironment”and“immunotherapy”.Exploring the effects of specific gut microbiota or derived metabolites on the behavior of immune cells in the TIME,regulating the secretion of immune molecules,and influencing immunotherapy are research hotspots and future research directions.

Unraveling brain aging through the lens of oral microbiota

The oral cavity is a complex physiological community encompassing a wide range of microorganisms.Dysbiosis of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative diseases.Recent studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention strategies.In this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and neurodegeneration.We also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

Exploring the interaction between the gut microbiota and cyclic adenosine monophosphate-protein kinase A signaling pathway:a potential therapeutic approach for neurodegenerative diseases

The interaction between the gut microbiota and cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling pathway in the host's central nervous system plays a crucial role in neurological diseases and enhances communication along the gut–brain axis.The gut microbiota influences the cAMP-PKA signaling pathway through its metabolites,which activates the vagus nerve and modulates the immune and neuroendocrine systems.Conversely,alterations in the cAMP-PKA signaling pathway can affect the composition of the gut microbiota,creating a dynamic network of microbial-host interactions.This reciprocal regulation affects neurodevelopment,neurotransmitter control,and behavioral traits,thus playing a role in the modulation of neurological diseases.The coordinated activity of the gut microbiota and the cAMP-PKA signaling pathway regulates processes such as amyloid-β protein aggregation,mitochondrial dysfunction,abnormal energy metabolism,microglial activation,oxidative stress,and neurotransmitter release,which collectively influence the onset and progression of neurological diseases.This study explores the complex interplay between the gut microbiota and cAMP-PKA signaling pathway,along with its implications for potential therapeutic interventions in neurological diseases.Recent pharmacological research has shown that restoring the balance between gut flora and cAMP-PKA signaling pathway may improve outcomes in neurodegenerative diseases and emotional disorders.This can be achieved through various methods such as dietary modifications,probiotic supplements,Chinese herbal extracts,combinations of Chinese herbs,and innovative dosage forms.These findings suggest that regulating the gut microbiota and cAMP-PKA signaling pathway may provide valuable evidence for developing novel therapeutic approaches for neurodegenerative diseases.

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

Traumatic brain injury is a prevalent disorder of the central nervous system.In addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are lacking.Intestinal dysfunction is a significant consequence of traumatic brain injury.Being the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous system.The gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated complications.We comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut microbiota.Additionally,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain injury.This review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effects of the“brain-gut-microbiota axis.”

Effect of dietary fibre on the gastrointestinal microbiota during critical illness:A scoping review

The systemic effects of gastrointestinal(GI)microbiota in health and during chronic diseases is increasingly recognised.Dietary strategies to modulate the GI microbiota during chronic diseases have demonstrated promise.While changes in dietary intake can rapidly change the GI microbiota,the impact of dietary changes during acute critical illness on the microbiota remain uncertain.Dietary fibre is metabolised by carbohydrate-active enzymes and,in health,can alter GI microbiota.The aim of this scoping review was to describe the effects of dietary fibre supplementation in health and disease states,specifically during critical illness.Randomised controlled trials and prospective cohort studies that include adults(>18 years age)and reported changes to GI microbiota as one of the study outcomes using non-culture methods,were identified.Studies show dietary fibres have an impact on faecal microbiota in health and disease.The fibre,inulin,has a marked and specific effect on increasing the abundance of faecal Bifidobacteria.Short chain fatty acids produced by Bifidobacteria have been shown to be beneficial in other patient populations.Very few trials have evaluated the effect of dietary fibre on the GI microbiota during critical illness.More research is necessary to establish optimal fibre type,doses,duration of intervention in critical illness.

Gut microbiota-astrocyte axis: new insights into age-related cognitive decline

With the rapidly aging human population,age-related cognitive decline and dementia are becoming increasingly prevalent worldwide.Aging is considered the main risk factor for cognitive decline and acts through alterations in the composition of the gut microbiota,microbial metabolites,and the functions of astrocytes.The microbiota–gut–brain axis has been the focus of multiple studies and is closely associated with cognitive function.This article provides a comprehensive review of the specific changes that occur in the composition of the gut microbiota and microbial metabolites in older individuals and discusses how the aging of astrocytes and reactive astrocytosis are closely related to age-related cognitive decline and neurodegenerative diseases.This article also summarizes the gut microbiota components that affect astrocyte function,mainly through the vagus nerve,immune responses,circadian rhythms,and microbial metabolites.Finally,this article summarizes the mechanism by which the gut microbiota–astrocyte axis plays a role in Alzheimer’s and Parkinson’s diseases.Our findings have revealed the critical role of the microbiota–astrocyte axis in age-related cognitive decline,aiding in a deeper understanding of potential gut microbiome-based adjuvant therapy strategies for this condition.

Longitudinal assessment of peripheral organ metabolism and the gut microbiota in an APP/PS1 transgenic mouse model of Alzheimer’s disease

Alzheimer’s disease not only affects the brain,but also induces metabolic dysfunction in peripheral organs and alters the gut microbiota.The aim of this study was to investigate systemic changes that occur in Alzheimer’s disease,in particular the association between changes in peripheral organ metabolism,changes in gut microbial composition,and Alzheimer’s disease development.To do this,we analyzed peripheral organ metabolism and the gut microbiota in amyloid precursor protein-presenilin 1(APP/PS1)transgenic and control mice at 3,6,9,and 12 months of age.Twelve-month-old APP/PS1 mice exhibited cognitive impairment,Alzheimer’s disease-related brain changes,distinctive metabolic disturbances in peripheral organs and fecal samples(as detected by untargeted metabolomics sequencing),and substantial changes in gut microbial composition compared with younger APP/PS1 mice.Notably,a strong correlation emerged between the gut microbiota and kidney metabolism in APP/PS1 mice.These findings suggest that alterations in peripheral organ metabolism and the gut microbiota are closely related to Alzheimer’s disease development,indicating potential new directions for therapeutic strategies.

Gastric low-grade mucosal-associated lymphoid tissue-lymphoma: Helicobacter pylori and beyond

The stomach is the most frequently involved site for extranodal lymphomas,accounting for nearly two-thirds of all gastrointestinal cases.It is widely accepted that gastric B-cell,low-grade mucosal-associated lymphoid tissue(MALT)-lymphoma is caused by Helicobacter pylori(H.pylori)infection.MALT-lymphomas may engender different clinical and endoscopic patterns.Often,diagnosis is confirmed in patients with only vague dyspeptic symptoms and without macroscopic lesions on gastric mucosa.H.pylori eradication leads to lymphoma remission in a large number of patients when treatment occurs at an early stage(Ⅰ-Ⅱ1).Neoplasia confined to the submucosa,localized in the antral region of the stomach,and without API2-MALT1 translocation,shows a high probability of remission following H.pylori eradication.When both bacterial infection and lymphoma recur,further eradication therapy is generally effective.Radiotherapy,chemotherapy and,in selected cases,surgery are the available therapeutic options with a high success rate for those patients who fail to achieve remission,while data on immunotherapy with monoclonal antibodies (rituximab)are still scarce.The 5-year survival rate is higher than 90%,but careful,long-term follow-up is required in these patients since lymphoma recurrence has been reported in some cases.

Mucosal-associated invariant T cells in hepatitis B virus-related liver failure

BACKGROUND Liver failure has high mortality and poor prognosis,and establishing new reliable markers for predicting its prognosis is necessary.Mucosal-associated invariant T(MAIT)cells are a novel population of innate-like lymphocytes involved in inflammatory liver disease,and their potential role in liver failure remains unclear.AIM To investigate alteration of circulating MAIT cells and assess its prognostic value in patients with hepatitis B virus(HBV)-related liver failure.METHODS We recruited 55 patients with HBV-related liver failure,48 patients with chronic hepatitis B and 40 healthy controls(HCs)from Nantong Third People’s Hospital Affiliated to Nantong University.Peripheral blood mononuclear cells were isolated,and the percentage and number of circulating MAIT cells were detected by flow cytometry.Plasma levels of interleukin(IL)-7,IL-12p70,IL-18 and interferon-αwere measured by Luminex assay.RESULTS Circulating MAIT cells were significantly decreased in HBV-related liver failure patients(percentage:2.00±1.22 vs 5.19±1.27%,P<0.0001;number:5.47±4.93 vs 84.43±19.59,P<0.0001)compared with HCs.More importantly,there was a significant reduction of MAIT cells in patients with middle/late-stage compared with early-stage liver failure.Circulating MAIT cells partially recovered after disease improvement,both in percentage(4.01±1.21 vs 2.04±0.95%,P<0.0001)and in cell count(17.24±8.56 vs 7.41±4.99,P<0.0001).The proportion(2.29±1.01 vs 1.58±1.38%,P<0.05)and number(7.30±5.70 vs 2.94±1.47,P<0.001)of circulating MAIT cells were significantly higher in the survival group than in the dead/liver transplantation group,and the Kaplan–Meier curve showed that lower expression of circulating MAIT cells(both percentage and cell count)predicted poor overall survival(P<0.01).Also,the levels of IL-12(20.26±5.42 pg/mL vs 17.76±2.79 pg/mL,P=0.01)and IL-18(1470.05±1525.38 pg/mL vs 362.99±109.64 pg/mL,P<0.0001)were dramatically increased in HBV-related liver failure patients compared with HCs.CONCLUSION Circulating MAIT cells may play an important role in the process of HBV-related liver failure and can be an important prognostic marker.

Incorporating mucosal-associated invariant T cells into the pathogenesis of chronic liver disease

Mucosal-associated invariant T(MAIT)cells have been described in liver and nonliver diseases,and they have been ascribed antimicrobial,immune regulatory,protective,and pathogenic roles.The goals of this review are to describe their biological properties,indicate their involvement in chronic liver disease,and encourage investigations that clarify their actions and therapeutic implications.English abstracts were identified in PubMed by multiple search terms,and bibliographies were developed.MAIT cells are activated by restricted non-peptides of limited diversity and by multiple inflammatory cytokines.Diverse pro-inflammatory,anti-inflammatory,and immune regulatory cytokines are released;infected cells are eliminated;and memory cells emerge.Circulating MAIT cells are hyper-activated,immune exhausted,dysfunctional,and depleted in chronic liver disease.This phenotype lacks disease-specificity,and it does not predict the biological effects.MAIT cells have presumed protective actions in chronic viral hepatitis,alcoholic hepatitis,non-alcoholic fatty liver disease,primary sclerosing cholangitis,and decompensated cirrhosis.They have pathogenic and pro-fibrotic actions in autoimmune hepatitis and mixed actions in primary biliary cholangitis.Local factors in the hepatic microenvironment(cytokines,bile acids,gut-derived bacterial antigens,and metabolic by-products)may modulate their response in individual diseases.Investigational manipulations of function are warranted to establish an association with disease severity and outcome.In conclusion,MAIT cells constitute a disease-nonspecific,immune response to chronic liver inflammation and infection.Their pathological role has been deduced from their deficiencies during active liver disease,and future investigations must clarify this role,link it to outcome,and explore therapeutic interventions.

Mucosal-associated invariant T cells and oral microbiome in persistent apical periodontitis

Opportunistic bacteria in apical periodontitis (AP) may pose a risk for systemic dissemination.Mucosal-associated invariant T (MAIT) cells are innate-like T cells with a broad and potent antimicrobial activity important for gut mucosal integrity.It was recently shown that MAIT cells are present in the oral mucosal tissue,but the involvement of MAIT cells in AP is unknown.Here,comparison of surgically resected AP and gingival tissues demonstrated that AP tissues express significantly higher levels of Vα7.2-Jα33,Vα7.2- Jα20,Vα7.2-Jα12,Cα and tumour necrosis factor (TNF),interferon (IFN)-γ and interleukin (IL)-17A transcripts,resembling a MAIT cell signature.Moreover,in AP tissues the MR1-restricted MAIT cells positive for MR1–5-OP-RU tetramer staining appeared to be of similar levels as in peripheral blood but consisted mainly of CD4^+ subset.Unlike gingival tissues,the AP microbiome was quantitatively impacted by factors like fistula and high patient age and had a prominent riboflavin-expressing bacterial feature.When merged in an integrated view,the examined immune and microbiome data in the sparse partial least squares discriminant analysis could identify bacterial relative abundances that negatively correlated with Vα7.2-Jα33,Cα,and IL-17A transcript expressions in AP,implying that MAIT cells could play a role in the local defence at the oral tissue barrier.In conclusion,we describe the presence of MAIT cells at the oral site where translocation of oral microbiota could take place.These findings have implications for understanding the immune sensing of polymicrobial-related oral diseases.

Primary mucosal-associated lymphoid tissue extranodal marginal zone lymphoma of the bladder from an imaging perspective: A case report

BACKGROUND Mucosal-associated lymphoid tissue extranodal marginal zone(MALT)lymphoma is a low-grade tumor that rarely occurs in the urinary bladder.There is currently no consensus on the common imaging findings or most appropriate treatment in MALT lymphoma in the urinary bladder due to the limited number of reports.CASE SUMMARY A 48-year-old woman was admitted to the hospital with a 1-year history of macroscopic hematuria.Imaging showed a large homogeneous mass with an unclear boundary and an irregular morphology in the bladder.The mass had an abundant blood supply.For further diagnosis,transurethral cystoscopic biopsy and bone marrow biopsy was performed,and the patient was finally diagnosed with primary MALT lymphoma of the bladder.R-CHOP chemotherapy was carried out.After three cycles of chemotherapy,the mass disappeared and the bladder wall thickness was only 4 mm,which indicated excellent therapeutic response to the chemotherapy.To date,the patient remains asymptomatic and she visits our hospital regularly for the completion of the remaining chemotherapy cycles.CONCLUSION Primary MALT lymphoma of the bladder is rare,and there are certain characteristics in the ultrasonographic findings.Imaging findings play an important role in evaluating the therapeutic efficacy and are critical during long-term follow-up after therapy.

Mucosal-associated invariant T cells from induced pluripotent stem cells:A novel approach for modeling human diseases

Mice have frequently been used to model human diseases involving immune dysregulation such as autoimmune and inflammatory diseases.These models help elucidatethe mechanisms underlying the disease and in the development of novel therapies.However,if mice are deficient in certain cells and/or effectors associated with human diseases,how can their functions be investigated in this species?Mucosal-associated invariant T(MAIT)cells,a novel innate-like T cell family member,are a good example.MAIT cells are abundant in humans but scarce in laboratory mice.MAIT cells harbor an invariant T cell receptor and recognize nonpeptidic antigens vitamin B2metabolites from bacteria and yeasts.Recent studies have shown that MAIT cells play a pivotal role in human diseases such as bacterial infections and autoimmune and inflammatory diseases.MAIT cells possess granulysin,a human-specific effector molecule,but granulysin and its homologue are absent in mice.Furthermore,MAIT cells show poor proliferation in vitro.To overcome these problems and further our knowledge of MAIT cells,we have established a method to expand MAIT cells via induced pluripotent stem cells(iP SCs).In this review,we describe recent advances in the field of MAIT cell research and our approach for human disease modeling with iP SCderived MAIT cells.

Ginkgo biloba extract alleviates fatty liver hemorrhagic syndrome in laying hens via reshaping gut microbiota

Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be elucidated.Here,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.Results The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and ALP.The lipid accumulation and pathological score of liver were also relieved after GBE treatment.Moreover,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the liver.Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the cecum.Meanwhile,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut microbiota.Finally,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota.Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.