Imbalance of Circulating Follicular Regulatory and Follicular Helper T Cell Subpopulations Is Associated with Disease Progression and Serum CYFRA 21-1 Levels in Patients with Non-small Cell Lung Cancer

Objective This study aimed to investigate the changes of follicular helper T(TFH)and follicular regulatory T(TFR)cell subpopulations in patients with non-small cell lung cancer(NSCLC)and their significance.Methods Peripheral blood was collected from 58 NSCLC patients at different stages and 38 healthy controls.Flow cytometry was used to detect TFH cell subpopulation based on programmed death 1(PD-1)and inducible co-stimulator(ICOS),and TFR cell subpopulation based on cluster determinant 45RA(CD45RA)and forkhead box protein P3(FoxP3).The levels of interleukin-10(IL-10),interleukin-17a(IL-17a),interleukin-21(IL-21),and transforming growth factor-β(TGF-β)in the plasma were measured,and changes in circulating B cell subsets and plasma IgG levels were also analyzed.The correlation between serum cytokeratin fragment antigen 21-1(CYFRA 21-1)levels and TFH,TFR,or B cell subpopulations was further explored.Results The TFR/TFH ratio increased significantly in NSCLC patients.The CD45RA^(+)FoxP3^(int) TFR subsets were increased,with their proportions increasing in stages Ⅱ to Ⅲ and decreasing in stage IV.PD-1^(+)ICOS+TFH cells showed a downward trend with increasing stages.Plasma IL-21 and TGF-β concentrations were increased in NSCLC patients compared with healthy controls.Plasmablasts,plasma IgG levels,and CD45RA^(+)FoxP3^(int) TFR cells showed similar trends.TFH numbers and plasmablasts were positively correlated with CYFRA 21-1 in stages Ⅰ-Ⅲ and negatively correlated with CYFRA 21-1 in stage IV.Conclusion Circulating TFH and TFR cell subpopulations and plasmablasts dynamically change in different stages of NSCLC,which is associated with serum CYFRA 21-1 levels and reflects disease progression.

Subpopulations of regulatory T cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular disease.Since pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early interventions.There is evidence that regulatory T cells(Tregs)are involved in the development of atherosclerosis.Therefore,the present study aimed to identify and investigate associations with Tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated signatures.Methods:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking medication.Ultrasound of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were performed.Additionally,tests were conducted to assess blood lipids and determine glucose levels.Immunophenotyping of Tregs and their subtypes(resting(rTregs)and effector/memory(mTregs))was performed by 8-chanel flow cytometry.Participants were categorized according to atherosclerotic plaque status.Linear and logistic regression models were used to analyze associations between parameters.Results:SAP was detected in a total of 29 participants.The participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).The participants with SAP were characterized by a lower percentage of rTregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mTregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and mTregs(OR=1.05(95%CI:1.021.10))as independent risk factors for SAP.Stepwise linear regression could reveal an association of peak oxygen uptake(β=0.441),low-density lipoprotein(LDL)(β=0.096),and SAP(β=6.733)with mTregs and LDL(β=0.104)with rTregs.Conclusion:While at an early stage of SAP,the total proportion of Tregs gives no indication of vascular changes,this is indicated by a shift in the Treg subgroups.Factors such as serum LDL or cardiopulmonary fitness may be associated with this shift and may also be additional diagnostic indicators.This could be used to initiate lifestyle-based preventive measures at an early stage,which may have a protective effect against disease progression.

Milk fat globule membrane supplementation protects againstβ-lactoglobul-ininduced food allergy in mice via upregulation of regulatory T cells and enhancement of intestinal barrier in a microbiota-derived short-chain fatty acids manner

Milk fat globule membrane(MFGM),which contains abundant glycoproteins and phospholipids,exerts beneficial effects on intestinal health and immunomodulation.The aim of this study was to evaluate the protective effects and possible underlying mechanisms of MFGM on cow’s milk allergy(CMA)in aβ-lactoglobulin(BLG)-induced allergic mice model.MFGM was supplemented to allergic mice induced by BLG at a dose of 400 mg/kg body weight.Results demonstrated that MFGM alleviated food allergy symptoms,decreased serum levels of lipopolysaccharide,pro-inflammatory cytokines,immunoglobulin(Ig)E,Ig G1,and Th2 cytokines including interleukin(IL)-4,while increased serum levels of Th1 cytokines including interferon-γand regulatory T cells(Tregs)cytokines including IL-10 and transforming growth factor-β.MFGM modulated gut microbiota and enhanced intestinal barrier of BLG-allergic mice,as evidenced by decreased relative abundance of Desulfobacterota,Rikenellaceae,Lachnospiraceae,and Desulfovibrionaceae,while increased relative abundance of Bacteroidetes,Lactobacillaceae and Muribaculaceae,and enhanced expressions of tight junction proteins including Occludin,Claudin-1 and zonula occludens-1.Furthermore,MFGM increased fecal short-chain fatty acids(SCFAs)levels,which elevated G protein-coupled receptor(GPR)43 and GPR109A expressions.The increased expressions of GPR43 and GPR109A induced CD103+dendritic cells accumulation and promoted Tregs differentiation in mesenteric lymph node to a certain extent.In summary,MFGM alleviated CMA in a BLG-induced allergic mice model through enhancing intestinal barrier and promoting Tregs differentiation,which may be correlated with SCFAs-mediated activation of GPRs.These findings suggest that MFGM may be useful as a promising functional ingredient against CMA.

T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue regeneration.As the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the condition.After an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune response.This review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic stroke.We found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic effect.Th1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain injury.Th2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain injury.Immune interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke patients.Clinical trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic stroke.However,such studies have been relatively infrequent,and clinical experience is still insufficient.In summary,in ischemic stroke,T cell subsets and activated microglia act synergistically to regulate inflammatory progression,mainly by secreting inflammatory factors.In the future,a key research direction for ischemic stroke treatment could be rooted in the enhancement of anti-inflammatory factor secretion by promoting the generation of Th2 and Treg cells,along with the activation of M2-type microglia.These approaches may alleviate neuroinflammation and facilitate the repair of neural tissues.

Predicting the Prognosis and Immunotherapeutic Response of Triple-Negative Breast Cancer by Constructing a Prognostic Model Based on CD8+T Cell-Related Immune Genes

Objective Triple-negative breast cancer(TNBC)poses a significant challenge for treatment efficacy.CD8+T cells,which are pivotal immune cells,can be effectively analyzed for differential gene expression across diverse cell populations owing to rapid advancements in sequencing technology.By leveraging these genes,our objective was to develop a prognostic model that accurately predicts the prognosis of patients with TNBC and their responsiveness to immunotherapy.Methods Sample information and clinical data of TNBC were sourced from The Cancer Genome Atlas and METABRIC databases.In the initial stage,we identified 67 differentially expressed genes associated with immune response in CD8+T cells.Subsequently,we narrowed our focus to three key genes,namely CXCL13,GBP2,and GZMB,which were used to construct a prognostic model.The accuracy of the model was assessed using the validation set data and receiver operating characteristic(ROC)curves.Furthermore,we employed various methods,including Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway,immune infiltration,and correlation analyses with CD274(PD-L1)to explore the model's predictive efficacy in immunotherapeutic responses.Additionally,we investigated the potential underlying biological pathways that contribute to divergent treatment responses.Results We successfully developed a model capable of predicting the prognosis of patients with TNBC.The areas under the curve(AUC)values for the 1-,3-,and 5-year survival predictions were 0.618,0.652,and 0.826,respectively.Employing this risk model,we stratified the samples into high-and low-risk groups.Through KEGG enrichment analysis,we observed that the high-risk group predominantly exhibited enrichment in metabolism-related pathways such as drug and chlorophyll metabolism,whereas the low-risk group demonstrated significant enrichment in cytokine pathways.Furthermore,immune landscape analysis revealed noteworthy variations between(PD-L1)expression and risk scores,indicating that our model effectively predicted the response of patients to immune-based treatments.Conclusion Our study demonstrates the potential of CXCL13,GBP2,and GZMB as prognostic indicators of clinical outcomes and immunotherapy responses in patients with TNBC.These findings provide valuable insights and novel avenues for developing immunotherapeutic approaches targeting TNBC.

Regulatory T cells in skin regeneration and wound healing

As the body’s integumentary system,the skin is vulnerable to injuries.The subsequent wound healing processes aim to restore dermal and epidermal integrity and functionality.To this end,multiple tissue-resident cells and recruited immune cells cooperate to efficiently repair the injured tissue.Such temporally-and spatially-coordinated interplay necessitates tight regulation to prevent collateral damage such as overshooting immune responses and excessive inflammation.In this context,regulatory T cells(Tregs)hold a key role in balancing immune homeostasis and mediating cutaneous wound healing.A comprehensive understanding of Tregs’multifaceted field of activity may help decipher wound pathologies and,ultimately,establish new treatment modalities.Herein,we review the role of Tregs in orchestrating the regeneration of skin adnexa and catalyzing healthy wound repair.Further,we discuss how Tregs operate during fibrosis,keloidosis,and scarring.

Revolutionizing tumor immunotherapy:unleashing the power of progenitor exhausted T cells

In exploring persistent infections and malignancies, a distinctive subgroup of CD8^(+) T cells, progenitor exhausted CD8^(+) T(Tpex) cells, has been identified. These Tpex cells are notable for their remarkable self-renewal and rapid proliferation abilities. Recent strides in immunotherapy have demonstrated that Tpex cells expand and differentiate into responsive exhausted CD8^(+) T cells, thus underscoring their critical role in the immunotherapeutic retort. Clinical examinations have further clarified a robust positive correlation between the proportional abundance of Tpex cells and enhanced clinical prognosis. Tpex cells have found noteworthy applications in the formulation of inventive immunotherapeutic approaches against tumors. This review describes the functions of Tpex cells in the tumor milieu, particularly their potential utility in tumor immunotherapy. Precisely directing Tpex cells may be essential to achieving successful outcomes in immunotherapy against tumors.

Tumor-derived DEFB1 induces immune tolerance by inhibiting maturation of dendritic cell and impairing CD8+T cell function in esophageal squamous cell carcinoma

Objective:CD8+T cells are the key effector cells in the anti-tumor immune response.The mechanism underlying the infiltration of CD8+T cells in esophageal squamous cell carcinoma(ESCC)has not been clearly elucidated.Methods:Fresh ESCC tissues were collected and grouped according to the infiltration density of CD8+T cells.After the transcriptome sequencing on these samples and the combined analyses with The Cancer Genome Atlas(TCGA)ESCC data,a secreted protein DEFB1 was selected to explore its potential role in the infiltration of CD8+T cells.Bioinformatics analyses,histological verification and in vitro experiments were then performed.Results:DEFB1 was highly expressed in ESCC,and the high expression of DEFB1 was an independent risk factor for overall survival.Since the up-regulation or down-regulation of DEFB1 did not affect the proliferation,migration and apoptosis of ESCC cells,we speculated that the oncogenic effect of DEFB1 was achieved by regulating microenvironmental characteristics.Bioinformatics analyses suggested that DEFB1 might play a major role in the inflammatory response and anti-tumor immune response,and correlate to the infiltration of immature dendritic cell(imDC)in ESCC.Histological analyses further confirmed that there were less CD8+T cells infiltrated,less CD83+mature DC(mDC)infiltrated and more CD1a+imDC infiltrated in those ESCC samples with high expression of DEFB1.After the treatment with recombinant DEFB1 protein,the maturation of DC was hindered significantly,followed by the impairment of the killing effects of T cells in both 2D and 3D culture in vitro.Conclusions:Tumor-derived DEFB1 can inhibit the maturation of DC and weaken the function of CD8+T cells,accounting for the immune tolerance in ESCC.The role of DEFB1 in ESCC deserves further exploration.

Identification of prognostic molecular subtypes and model based on CD8+ T cells for lung adenocarcinoma

Background:Cytotoxic T lymphocytes(CD8+T)cells function critically in mediating anti-tumor immune response in cancer patients.Characterizing the specific functions of CD8+T cells in lung adenocarcinoma(LUAD)could help better understand local anti-tumor immune responses and estimate the effect of immunotherapy.Methods:Gens related to CD8+T cells were identified by cluster analysis based on the single-cell sequencing data of three LUAD tissues and their paired normal tissues.Weighted gene co-expression network analysis(WGCNA),consensus clustering,differential expression analysis,least absolute shrinkage and selection operator(LASSO)and Cox regression analysis were conducted to classify molecular subtypes for LUAD and to develop a risk model using prognostic genes related to CD8+T cells.Expression of the genes in the prognostic model,their effects on tumor cell invasion,and interactions with CD8+T cells were verified by cell experiments.Results:This study defined two LUAD clusters(CD8+0 and CD8+1)based on CD8+T cells,with cluster CD8+0 being significantly associated with the prognosis of LUAD.Three heterogeneous subtypes(clusters 1,2,and 3)differing in prognosis,genome mutation events,and immune status were categorized using 42 prognostic genes.A prognostic model created based on 11 significant genes(including CD200R1,CLEC17A,ZC3H12D,GNG7,SNX30,CDCP1,NEIL3,IGF2BP1,RHOV,ABCC2,and KRT81)was able to independently estimate the death risk for patients in different LUAD cohorts.Moreover,the model also showed general applicability in external validation cohorts.Low-risk patients could benefit more from taking immunotherapy and were significantly related to the resistance to anticancer drugs.The results from cell experiments demonstrated that the expression of CD200R1,CLEC17A,ZC3H12D,GNG7,and SNX30 was significantly downregulated,while that of CDCP1,NEIL3,IGF2BP1,RHOV,ABCC2 and KRT81 was upregulated in LUAD cells.Inhibition of CD200R1 greatly increased the invasiveness of the LUAD cells,but inhibiting CDCP1 expression weakened the invasion ability of LUAD cells.Conclusion:This study defined two prognostic CD8+T cell clusters and classified three heterogeneous molecular subtypes for LUAD.A prognostic model predictive of the potential effects of immunotherapy on LUAD patients was developed.

Efficacy of acupoint injection in the treatment of chronic eczema and its influence on peripheral blood T cells

BACKGROUND Chronic eczema significantly impacts daily life,social interactions,and quality of life;however,no curative treatment has been identified.AIM To determine the clinical efficacy of acupoint injection for chronic eczema and its influence on peripheral blood T cells.METHODS Eighty patients with chronic eczema treated at our hospital between June 2022 and March 2023 were randomly assigned to a control group(n=40),which received conventional Western medicine treatment,or an observation group(n=40),which received routine Western medicine treatment plus acupoint injection of triamcinolone acetonide.Response and adverse reaction rates,as well as differences in the levels of serum cytokines IFN-γ,IL-2,IL-4,and IL-10 before and after treatment were investigated.RESULTS No difference in overall response rates were found between the observation and control groups(100%vs 90%,respectively;P>0.05);however,the observation group had a higher marked response rate than the control group(87.5%vs 52.5%;P<0.05).Both groups had decreased Eczema Area and Severity Index scores and increased pruritus after treatment(P<0.05),particularly in the observation group(P<0.05).The observation group had an adverse reaction rate of 2.5%(1/40),which did not differ significantly from that of the control group(P>0.05).The observation group exhibited higher post-treatment INF-γand IL-2 but lower IL-4 levels than the control group(P<0.05);however,no significant inter-group difference was observed in post-treatment IL-10 levels(P>0.05).CONCLUSION Acupoint injection of triamcinolone acetonide is safe and effective in treating chronic eczema.Its therapeutic mechanism is related to the regulation of peripheral blood T cell levels,inhibition of inflammatory reactions,and mitigation of immune imbalance.

The Value of γδ T Cells in Lung Infections and Advances in Diagnosis and Treatment

Lung infections are usually caused by pathogenic microorganisms and are a disease with high morbidity and mortality. In clinical practice, the use of broad-spectrum antibiotics has become increasingly common, but this has also led to the problem of antibiotic abuse and irrational use, which in turn has spawned the emergence of multidrug-resistant bacteria, making the treatment of lung infections more complex and difficult. In the human immune system, γδ T cells play a crucial role in defense against foreign pathogens and regulation of autoimmune responses. These cells act as a bridge between innate and adaptive immunity and can be rapidly activated in the early stages of infection to produce inflammatory factors and chemokines that attract other immune cells to the site of infection. Recent advances have shown that γδ T cells not only play a direct role in the innate immunity of pathogen infection, but are also involved in regulating the subsequent adaptive immune response. The aim of this review is to explore the mechanism of γδ T cells in lung infections and to summarize the current progress of clinical research, with the aim of providing new scientific basis and therapeutic strategies for the treatment of lung infections.

Combined TIM-3 and PD-1 blockade restrains hepatocellular carcinoma development by facilitating CD4+ and CD8+T cellmediated antitumor immune responses

BACKGROUND Immune checkpoint inhibitors(ICIs)targeting programmed cell death protein 1(PD-1)and T cell immunoglobulin and mucin domain-containing protein 3(TIM-3)are beneficial to the resumption of anti-tumor immunity response and hold extreme potential as efficient therapies for certain malignancies.However,ICIs with a single target exhibit poor overall response rate in hepatocellular carcinoma(HCC)patients due to the complex pathological mechanisms of HCC.AIM To investigate the effects of combined TIM-3 and PD-1 blockade on tumor development in an HCC mouse model,aiming to identify more effective immunotherapies and provide more treatment options for HCC patients.METHODS The levels of PD-1 and TIM-3 on CD4+and CD8+T cells from tumor tissues,ascites,and matched adjacent tissues from HCC patients were determined with flow cytometry.An HCC xenograft mouse model was established and treated with anti-TIM-3 monoclonal antibody(mAb)and/or anti-PD-1 mAb.Tumor growth in each group was measured.Hematoxylin and eosin staining and immunohistochemical staining were used to evaluate T cell infiltration in tumors.The percentage of CD4+and CD8+T cells in tissue samples from mice was tested with flow cytometry.The percentages of PD-1+CD8+,TIM-3+CD8+,and PD-1+TIM-3+CD8+T cells was accessed by flow cytometry.The levels of the cytokines including tumor necrosis factor alpha(TNF-α),interferon-γ(IFN-γ),interleukin(IL)-6,and IL-10 in tumor tissues were gauged with enzyme-linked immunosorbent assay kits.RESULTS We confirmed that PD-1 and TIM-3 expression was substantially upregulated in CD4+and CD8+T cells isolated from tumor tissues and ascites of HCC patients.TIM-3 mAb and PD-1 mAb treatment both reduced tumor volume and weight,while combined blockade had more substantial anti-tumor effects than individual treatment.Then we showed that combined therapy increased T cell infiltration into tumor tissues,and downregulated PD-1 and TIM-3 expression on CD8+T cells in tumor tissues.Moreover,combined treatment facilitated the production of T cell effector cytokines TNF-α and IFN-γ,and reduced the production of immunosuppressive cytokines IL-10 and IL-6 in tumor tissues.Thus,we implicated that combined blockade could ameliorate T cell exhaustion in HCC mouse model.CONCLUSION Combined TIM-3 and PD-1 blockade restrains HCC development by facilitating CD4+ and CD8+T cell-mediated antitumor immune responses.

The anti-neoplastic effects of metformin modulate the acquired phenotype of fbroblast cells in the breast cancer-normal fbroblast co-culture system

Intracellular communications between breast cancer and fibroblast cells were reported to be involved in cancer proliferation,growth,and therapy resitance.The hallmarks of cancer fibroblast interactions,consisting of caveolin 1(Cav1)and mono-carboxylate ransporter 4(MCT4)(metabolic coupling markers),along with IL-6,TGFB,and lactate secretion,are considered robust biomarkers predicting recurrence and metastasis.In order to promote a novel phenotype in normal fibroblasts,we predicted that breast cancer cells could be able to cause loss of Cavl and increase of MCT4,as well as elevate IL 6 and TGF in nearby nomal fibroblasts.We created a co culture model using breast cancer(4T1)and normal fibroblast(NIH3T3)cell lines cultured under specific experimental conditions in order to directly test our theory.Moreover,we show that long-term co-culture of breast cancer cells and normal fibroblasts promotes loss of Cavl and gain of MCT4 in adjacent fibroblasts and increase lactate secretion.These results were validated using the monoculture of each group separately as a control.In this system,we show that me tformin inhibits IL-6 and TGFB secretion and re expresses Cavl in both cells.However,MCT4 and lactate stayed high after treatment with metformin.In conclusion,our work shows that co-culture with breast cancer cells may cause signifcant alterations in the phenotype and secretion of normal fibroblasts.Metformin,however,may change this state and affect fibroblasts'acquired phenotypes.Moreover,mitochondrial inhibition by metformin after 8 days of treatment,signi ficantly hinders tumor growth in mouse model of breast cancer.

Stem cell-like memory T cells:Role in viral infections and autoimmunity

Stem cell-like memory T(TSCM)cells possess stem cell properties including multipotency and self-renewal and are being recognized as emerging players in various human diseases.Advanced technologies such as multiparametric flowcytometry and single cell sequencing have enabled their identification and molecular characterization.In case of chronic viral diseases such as human immunodeficiency virus-1,CD4+T_(SCM) cells,serve as major reservoirs of the latent virus.However,during immune activation and functional exhaustion of effector T cells,these cells also possess the potential to replenish the pool of functional effector cells to curtail the infection.More recently,these cells are speculated to play important role in protective immunity following acute viral infections such as coronavirus disease 2019 and might be amenable for therapeutics by ex vivo expansion.Similarly,studies are also investigating their pathological role in driving autoimmune responses.However,there are several gaps in the understanding of the role of T_(SCM) cells in viral and autoimmune diseases to make them potential therapeutic targets.In this minireview,we have attempted an updated compilation of the dyadic role of these complex T_(SCM) cells during such human diseases along with their biology and transcriptional programs.

The Mechanisms of CD8+ T Cells Exhaustion in the Tumor Microenvironment and Immune Therapy

In the tumor immune microenvironment, CD8+ T cells differentiate towards functional failure. The exhaustion of CD8+ T cells (Tex) showed varying degrees of effect dysfunction, loss of proliferation ability, and sustained high expression of a variety of inhibitory receptors, with metabolic and epigenetic changes. Tex cells are heterogeneous, including several subsets with different characteristics at different stages of differentiation. Immune checkpoint inhibitors (ICIs) can restore the effect or function of Tex cells, indicating that this T cell subset plays a key role in tumor immunotherapy. The understanding of the mechanism of CD8+ T cell exhaustion will be helpful to the implementation of tumor immunotherapy. This article reviews the production, differentiation and functional characteristics of Tex cells and their relationship with tumor immunotherapy.

Neuro faces of beneficial T cells:essential in brain,impaired in aging and neurological diseases,and activated functionally by neurotransmitters and neuropeptides

T cells are essential for a healthy life,performing continuously:immune surveillance,recognition,protection,activation,suppression,assistance,eradication,secretion,adhesion,migration,homing,communications,and additional tasks.This paper describes five aspects of normal beneficial T cells in the healthy or diseased brain.First,normal beneficial T cells are essential for normal healthy brain functions:cognition,spatial learning,memory,adult neurogenesis,and neuroprotection.T cells decrease secondary neuronal degeneration,increase neuronal survival after central nervous system(CNS) injury,and limit CNS inflammation and damage upon injury and infection.Second,while pathogenic T cells contribute to CNS disorders,recent studies,mostly in animal models,show that specific subpopulations of normal beneficial T cells have protective and regenerative effects in seve ral neuroinflammatory and neurodegenerative diseases.These include M ultiple Sclerosis(MS),Alzheimer’s disease,Parkinson’s disease,Amyotrophic Lateral Sclerosis(ALS),stro ke,CNS trauma,chronic pain,and others.Both T cell-secreted molecules and direct cell-cell contacts deliver T cell neuroprotective,neuro regenerative and immunomodulato ry effects.Third,normal beneficial T cells are abnormal,impaired,and dysfunctional in aging and multiple neurological diseases.Different T cell impairments are evident in aging,brain tumors(mainly Glioblastoma),seve re viral infections(including COVID-19),chro nic stress,major depression,schizophrenia,Parkinson’s disease,Alzheimer’s disease,ALS,MS,stro ke,and other neuro-pathologies.The main detrimental mechanisms that impair T cell function are activation-induced cell death,exhaustion,senescence,and impaired T cell stemness.Fo urth,several physiological neurotransmitters and neuro peptides induce by themselves multiple direct,potent,beneficial,and therapeutically-relevant effects on normal human T cells,via their receptors in T cells.This scientific field is called "Nerve-Driven Immunity".The main neurotransmitters and neuropeptides that induce directly activating and beneficial effects on naive normal human T cells are:dopamine,glutamate,GnRH-Ⅱ,neuropeptide Y,calcitonin gene-related peptide,and somatostatin.Fifth, "Personalized Adoptive Neuro-Immunotherapy".This is a novel unique cellular immunotherapy,based on the "Nerve-Driven Immunity" findings,which was recently designed and patented for safe and repeated rejuvenation,activation,and improvement of impaired and dysfunctional T cells of any person in need,by ex vivo exposure of the person’s T cells to neurotransmitters and neuropeptides.Personalized adoptive neuro-immunotherapy includes an early ex vivo personalized diagnosis,and subsequent ex vivo in vivo personalized adoptive therapy,tailo red according to the diagnosis.The Personalized Adoptive Neuro-Immunotherapy has not yet been tested in humans,pending validation of safety and efficacy in clinical trials,especially in brain tumors,chronic infectious diseases,and aging,in which T cells are exhausted and/or senescent and dysfunctional.

Donor-derived CD 19 CAR-T Cells versus Chemotherapy Plus Donor Lymphocyte Infusion for Treatment of Recurrent CD 19-positive B-ALL after Allogeneic Hematopoietic Stem Cell Transplantation

Objective:This study aimed to compare the efficacy of anti-CD19 chimeric antigen receptor T cells(CAR-T cells)versus chemotherapy plus donor lymphocyte infusion(chemo-DLI)for treating relapsed CD 19-positive B-cell acute lymphoblastic leukemia(B-ALL)after allogeneic hematopoietic stem cell transplantation(allo-HSCT).Methods:Clinical data of 43 patients with B-ALL who relapsed after allo-HSCT were retrospectively analyzed.Twenty-two patients were treated with CAR-T cells(CAR-T group),and 21 with chemotherapy plus DLI(chemo-DLI group).The complete remission(CR)and minimal residual disease(MRD)-negative CR rates,leukemia-free survival(LFS)rate,overall survival(OS)rate,and incidence of acute graft-versus-host disease(aGVHD),cytokine release syndrome(CRS)and immune effector cell-associated neurotoxicity syndrome(ICANS)were compared between the two groups.Results:The CR and MRD-negative CR rates in the CAR-T group(77.3%and 61.5%)were significantly higher than those in the chemo-DLI group(38.1%and 23.8%)(P=0.008 and P=0.003).The 1-and 2-year LFS rates in the CAR-T group were superior to those in the chemo-DLI group:54.5%and 50.0%vs.9.5%and 4.8%(P=0.0001 and P=0.00004).The 1-and 2-year OS rates in the CAR-T versus chemo-DLI group were 59.1%and 54.5%vs.19%and 9.5%(P=0.011 and P=0.003).Six patients(28.6%)with grade 2-4 aGVHD were identified in the chemo-DLI group.Two patients(9.1%)in the CAR-T group developed grade 1-2 aGVHD.Nineteen patients(86.4%)developed CRS in the CAR-T group,comprising grade 1-2 CRS in 13 patients(59.1%)and grade 3 CRS in 6 patients(27.3%).Two patients(9.1%)developed grade 1-2 ICANS.Conclusion:Donor-derived anti-CD19 CAR-T-cell therapy may be better,safer,and more effective than chemo-DLI for B-ALL patients who relapse after allo-HSCT.

T cells in pancreatic cancer stroma:Tryptophan metabolism plays an important role in immunoregulation

Several studies have shown that the immune system is highly regulated by tryptophan metabolism,which serves as an immunomodulatory factor.The indoleamine 2,3-dioxygenase 1(IDO1),as an intracellular enzyme that participates in metabolism of the essential amino acid tryptophan in the kynurenine pathway,is an independent prognostic marker for pancreatic cancer(PC).First,overexpression of IDO1 inhibits the maturation of dendritic cells and T-cell proliferation in the liver and spleen.Second,the high expression of kynurenine induces and activates the aryl hydrocarbon receptor,resulting in upregulated programmed cell death protein 1 expression.Third,the induction of IDO1 can lead to loss of the T helper 17 cell/regulatory T cell balance,mediated by the proximal tryptophan catabolite from IDO metabolism.In our study,we found that overexpression of IDO1 upregulated CD8+T cells and reduced natural killer T cells in pancreatic carcinoma in mice.Hence,it may be essential to pay more attention to tryptophan metabolism in patients,especially those who are tolerant to immunotherapy for PC.

Activation-induced pyroptosis contributes to the loss of MAIT cells in chronic HIV-1 infected patients

Background: Mucosal-associated invariant T(MAIT) cells are systemically depleted in human immunodeficiency virus type 1(HIV-1) infected patients and are not replenished even after successful combined antiretroviral therapy(cART).This study aimed to identify the mechanism underlying MAIT cell depletion.Methods: In the present study, we applied flow cytometry, single-cell RNA sequencing and immunohistochemical staining to evaluate the characteristics of pyroptotic MAIT cells in a total of 127 HIV-1 infected individuals, including 69 treatment-naive patients, 28 complete responders, 15 immunological non-responders, and 15 elite controllers, at the Fifth Medical Center of Chinese PLA General Hospital, Beijing, China.Results: Single-cell transcriptomic profiles revealed that circulating MAIT cells from HIV-1 infected subjects were highly activated, with upregulation of pyroptosis-related genes. Further analysis revealed that increased frequencies of pyroptotic MAIT cells correlated with markers of systemic T-cell activation, microbial translocation, and intestinal damage in cART-naive patients and poor CD4+ T-cell recovery in long-term cART patients. Immunohistochemical staining revealed that MAIT cells in the gut mucosa of HIV-1 infected patients exhibited a strong active gasdermin-D(GSDMD, marker of pyroptosis) signal near the cavity side, suggesting that these MAIT cells underwent active pyroptosis in the colorectal mucosa. Increased levels of the proinflammatory cytokines interleukin-12(IL-12) and IL-18 were observed in HIV-1 infected patients. In addition, activated MAIT cells exhibited an increased pyroptotic phenotype after being triggered by HIV-1 virions, T-cell receptor signals, IL-12 plus IL-18, and combinations of these factors, in vitro.Conclusions: Activation-induced MAIT cell pyroptosis contributes to the loss of MAIT cells in HIV-1 infected patients,which could potentiate disease progression and poor immune reconstitution.

Pien Tze Huang alleviates Concanavalin A-induced autoimmune hepatitis by regulating intestinal microbiota and memory regulatory T cells

BACKGROUND Traditional Chinese medicine has used the drug Pien Tze Huang(PTH),a classic prescription,to treat autoimmune hepatitis(AIH).However,the precise mode of action is still unknown.AIM To investigate the mechanism of PTH in an AIH mouse model by determining the changes in gut microbiota structure and memory regulatory T(mTreg)cells functional levels.METHODS Following induction of the AIH mouse model induced by Concanavalin A(Con A),prophylactic administration of PTH was given for 10 d.The levels of mTreg cells were measured by flow cytometry,and intestinal microbiota was analyzed by 16S rRNA analysis,while western blotting was used to identify activation of the toll-like receptor(TLR)2,TLR4/nuclear factor-κB(NF-κB),and CXCL16/CXCR6 signaling pathways.RESULTS In the liver of mice with AIH,PTH relieved the pathological damage and reduced the numbers of T helper type 17 cells and interferon-γ,tumor necrosis factor-alpha,interleukin(IL)-1β,IL-2,IL-6,and IL-21 expression.Simultaneously,PTH stimulated the abundance of helpful bacteria,promoted activation of the TLR2 signal,which may enhance Treg/mTreg cells quantity to produce IL-10,and suppressed activation of the TLR4/NF-κB and CXCL16/CXCR6 signaling pathways.CONCLUSION PTH regulates intestinal microbiota balance and restores mTreg cells to alleviate experimental AIH,which is closely related to the TLR/CXCL16/CXCR6/NF-κB signaling pathway.