Peripheral CD4^(+)CD8^(+) double positive T cells:A potential marker to evaluate renal impairment susceptibility during systemic lupus erythematosus

Lupus nephritis(LN) has a high incidence in systemic lupus erythematosus(SLE) patients, but there is a lack of sensitive predictive markers. The purpose of the study was to investigate the association between the CD4^(+)CD8^(+)double positive T(DPT) lymphocytes and LN. The study included patients with SLE without renal impairment(SLE-NRI), LN, nephritic syndrome(NS), or nephritis. Peripheral blood lymphocyte subsets were analyzed by flow cytometry. Biochemical measurements were performed with peripheral blood in accordance with the recommendations proposed by the National Center for Clinical Laboratories. The proportions of DPT cells in the LN group were significantly higher than that in the SLE-NRI group(t=4.012, P<0.001), NS group(t=3.240,P=0.001), and nephritis group(t=2.57, P=0.011). In the LN group, the risk of renal impairment increased significantly in a DPT cells proportion-dependent manner. The risk of LN was 5.136 times(95% confidence interval, 2.115–12.473) higher in cases with a high proportion of DPT cells than those whose proportion of DPT cells within the normal range. These findings indicated that the proportion of DPT cells could be a potential marker to evaluate LN susceptibility, and the interference of NS and nephritis could be effectively excluded when assessing the risk of renal impairment during SLE with DPT cell proportion.

Glutamine deprivation impairs function of infiltrating CD8^(+)T cells in hepatocellular carcinoma by inducing mitochondrial damage and apoptosis

BACKGROUND The functions of infiltrating CD8^(+)T cells are often impaired due to tumor cells causing nutrient deprivation in the tumor microenvironment.Thus,the mechanisms of CD8^(+)T cell dysfunction have become a hot research topic,and there is increased interest on how changes in metabolomics correlate with CD8^(+)T cell dysfunction.AIM To investigate whether and how glutamine metabolism affects the function of infiltrating CD8^(+)T cells in hepatocellular carcinoma.METHODS Immunohistochemical staining and immunofluorescence were performed on surgically resected liver tissues from patients.Differentially expressed genes in infiltrating CD8^(+)T cells in hepatocellular carcinoma were detected using RNA sequencing.Activated CD8^(+)T cells were co-cultured with Huh-7 cells for 3 d.The function and mitochondrial status of CD8^(+)T cells were analyzed by flow cytometry,quantitative real-time polymerase chain reaction,and transmission electron microscopy.Next,CD8^(+)T cells were treated with the mitochondrial protective and damaging agents.Functional alterations in CD8^(+)T cells were detected by flow cytometry.Then,complete medium without glutamine was used to culture cells and their functional changes and mitochondrial status were detected.RESULTS There were a large number of infiltrating PD-1+CD8^(+)T cells in liver cancer tissues.Next,we cocultured CD8^(+)T cells and Huh-7 cells to explore the regulatory effect of hepatoma cells on CD8^(+)T cells.Flow cytometry results revealed increased PD-1 expression and decreased secretion of perforin(PRF1)and granzyme B(GZMB)by CD8^(+)T cells in the co-culture group.Meanwhile,JC-1 staining was decreased and the levels of reactive oxygen species and apoptosis were increased in CD8^(+)T cells of the co-culture group;additionally,the mitochondria of these cells were swollen.When CD8^(+)T cells were treated with the mitochondrial protective and damaging agents,their function was restored and inhibited,respectively,through the mitochondrial damage and apoptotic pathways.Subsequently,complete medium without glutamine was used to culture cells.As expected,CD8^(+)T cells showed functional downregulation,mitochondrial damage,and apoptosis.CONCLUSION Glutamine deprivation impairs the function of infiltrating CD8^(+)T cells in hepatocellular carcinoma through the mitochondrial damage and apoptotic pathways.

肿瘤抗原多肽诱导的CD8^+CTL的体内外抗瘤效应

利用海绵移植模型,将Friend小鼠白血病病毒gag编码的二个多肽CCLCLTVFL(gPr80 gag 85-93)和RSPTNLAKV(Pr65 gag P30 131-139)分别注入正常或经FBL-3肿瘤细胞免疫过的C57BL/6小鼠皮下的植入海绵中,10天后,收集海绵中浸润淋巴细胞,在体外用免疫肽周期性刺激培养扩增。实验结果表明:用多肽体内免疫正常或经FBL-3免疫的B6小鼠均能诱导出对免疫多肽特异的CD8^+CTL。其中,P85-93多肽诱导的CD8^+CTL除能杀伤该多肽致敏的同系靶细胞外,还能特异性杀伤FBL-3瘤细胞.抗原多肽诱导的CD8^+CTL在体外经用免疫多肽致敏的同系小鼠脾细胞作周期性刺激并在低浓度IL-2的条件下培养,可长期生长并大量扩增。用体外培养扩增的P85-93多肽特异性CD8^+CTL过继转输治疗FBL-3荷瘤小鼠,能有效治愈FBL-3白血病荷瘤小鼠。上述结果表明,用肿瘤抗原多肽替代肿瘤细胞体内免疫动物可诱导特异性抗瘤效应的CD8^+CTL,并可在体外扩增用于肿瘤过继性免疫治疗。

Effect of Mg^(2+)level on the functions of CD8^(+)T lymphocytes and NK cells in patients with COVID-19

Objective:To investigate the changes of Mg^(2+) levels in serum and peripheral blood mononuclear cells(PBMCs)of patients with COVID-19 and its effects on the functions of CD8^(+)T lymphocytes and NK cells.Methods:A total of 165 COVID-19 patients hospitalized in Ezhou Central Hospital from January 20 to February 20,2020 were divided into mild/common group(98 cases)and severe/critical group(67 cases).At the same time,34 healthy persons were selected as the control group.Peripheral blood was collected and PBMCs were isolated,the level of Mg^(2+) in serum and PBMCs was detected.The subsets of CD8^(+)T lymphocytes and NK cell and the expression levels of their surface inhibitory molecular PD-1 and activator molecular NKG2D were detected by flow cytometry.The correlation between Mg^(2+) concentration and the expression levels of PD-1 and NKG2D was also analyzed.Results:Compared with the control group,the concentration of Mg^(2+) in serum and PBMCs,the counts of CD8^(+)T lymphocytes and NK cell in patients with mild/common and severe/critical groups were significantly reduced(P<0.05),while the expression level of surface inhibitory molecular PD-1 were significantly increased(P<0.05),while the expression level of the activation molecule NKG2D were significantly decreased(P<0.05).However,the changes of the above indicators in patients with severe/critical group were greater than those in the mild/common group(P<0.05).In addition,the Mg^(2+) concentration in COVID-19 patients was negatively correlated with the expression level of PD-1 on CD8^(+)T lymphocytes and NK cells(P<0.05),and positively correlated with the expression levels of NKG2D(P<0.05).Conclusion:The concentration of Mg^(2+) in the serum and PBMCs of COVID-19 patients is significantly reduced,which may cause the function of CD8^(+)T lymphocytes and NK cells to be inhibited.

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.

Expression of PD1 and BTLA on the CD8^+T Cell and γδT Cell Subsets in Peripheral Blood of Non-Small Cell Lung Cancer Patients

Objective To investigate the expression and regulation of programmed cell death protein 1(PD1),B lymphocyte and T lymphocyte attenuator(BTLA)in peripheral blood of patients with non-small cell lung cancer(NSCLC);to examine the correlation of the mRNA levels between PD and BTLA in NSCLC.Methods Flow cytometry was used to detect the expression of PD1 and BTLA on the surfaces of CD8^+T cells andγδ+T cells in the peripheral blood samples collected from 32 in-patients with stage IV NSCLC and 30 healthy individuals.We compared the expression of PD1 and BTLA on the surfaces ofγδ+T cells in the NSCLC patients with bone metastasis before and after the treatment of zoledronic acid.The correlations of PD1 and BTLA,as well as their ligands were analyzed using Pearson correlation analysis with the cBioPortal data platform.Results The frequency of PD1 on the surfaces of CD8^+T cells was significantly higher than that of theγδT cells in both healthy controls(t=2.324,P=0.024)and NSCLC patients(t=2.498,P=0.015).The frequency of PD1 on CD8^+T cells,rather than onγδ+T cells,was significantly upregulated in advanced NSCLC patients compared with that in healthy controls(t=4.829,P<0.001).The PD1+BTLA+γδT cells of the healthy controls were significantly lower than that of the NSCLC patients(t=2.422,P=0.0185).No differences in percentage of PD1+γδ+and BTLA+γδ+T cells were observed in 7 NSCLC patients with bone metastasis before and after zoledronic acid treatment.PD1 was positively correlated with BTLA in both lung adenocarcinoma(r=0.54;P<0.05)and lung squamous cell carcinoma(r=0.78;P<0.05).Conclusions The upregulation of co-inhibitory molecules occurs on the surfaces of both CD8^+T cells andγδT cells in advanced NSCLC,suggesting that these molecules were involved in regulating the inactivation of CD8^+T cells andγδ+T cells,immune escape and tumor invasion.

原发性胆汁性肝硬化患者中自身抗原丙酮酸脱氢酶特异性CD8+CTL表位预测及鉴定

目的鉴定原发性胆汁性肝硬化(PBC)患者中自身抗原丙酮酸脱氢酶(PDC-E2)上的HLA-A觹0201限制性CD8+CTL表位,为临床探索特异性免疫治疗奠定基础。方法应用数据库SYFPEITHI预测PDC-E2上两段涵盖B细胞表位和CD4+T细胞表位的氨基酸序列(163～184aa和36～49aa)附近可能存在的HLA-A觹0201限制性T细胞表位,再通过T2细胞株、细胞增殖试验和细胞毒性检测分别分析各抗原肽与HLA-A觹0201的结合力、诱导患者外周血单个核细胞(PBMCs)增殖能力及抗原肽诱导的抗原特异性T细胞杀伤毒性,逐步鉴定HLA-A觹0201限制性CD8+CTL细胞表位。结果数据库初步预测到5个可能性较大的HLA-A觹0201限制性抗原肽,其中两个抗原肽(159～167aa和165～174aa)显示与T2细胞上HLA-A觹0201分子有较高的亲和力,这两个抗原肽能刺激大部分HLA-A觹0201阳性PBC患者PBMC增殖,并且由其诱导产生的CTL具有特异杀伤活性。结论位于PDC-E2内酯酰区上的KLSEGDLLA穴159～167aa)和LLAEIETDKA穴165～174aa雪是PBC患者体内HLA-A觹0201限制性的CD8+CTL表位。

CD8^+调节性T细胞与器官移植

调节性T细胞（regulatory T cells，Treg）在维持机体免疫平衡方面发挥关键作用，对于器官移植术后诱导治疗和维持免疫耐受具有重要意义。

CD8^+T细胞依赖的急性移植物抗宿主病小鼠模型的建立

目的建立CD8^+T细胞依赖的急性移植物抗宿主病(GVHD)小鼠模型。方法分别以主要组织相容性抗原(MHC)相同,而次要组织相容性抗原(miHAs)不同的8～12周龄C3H．SW(H-2D^b,CD45．2^+)和B6/SJL(H-2D^b,CD45．1^+)雌性小鼠为供受体,从供体骨髓分离去除T细胞的骨髓细胞(T BM),与其脾脏和淋巴结来源的CD8^+T细胞混合,经尾静脉输注给受致死剂量^(137)γ照射的受体鼠。观察移植后受体的体重、毛色、皮肤和生存率的变化,并用流式细胞术(FACS)和组织病理学进一步分析受鼠靶器官细胞浸润和损伤状况。结果移植后受体鼠出现体重明显减轻、毛发脱落、皮肤溃疡等表现,并在28d后出现死亡；FACS证实浸润受鼠骨髓、脾脏和肝脏的细胞主要为CD45．2^+的供鼠细胞,实验组中还有大量CD45．2^+CD8^+T细胞浸润；组织病理学发现肝脏中大量淋巴细胞浸润,皮肤结构破坏,组织坏死。结论成功建立了miHAs不匹配的异基因骨髓移植诱导的CD8^+ T细胞依赖的GVHD动物模型,该模型模拟了目前临床病人采用的同种异基因骨髓移植配型方式,可为异基因骨髓移植GVHD发病机理及该病的防治研究提供良好的实验平台和工具。

Notoginsenoside Ft1 inhibits colorectal cancer growth by increasing CD8^(+)T cell proportion in tumor-bearing mice through the USP9X signaling pathway

The management of colorectal cancer(CRC)poses a significant challenge,necessitating the development of innovative and effective therapeutics.Our research has shown that notoginsenoside Ft1(Ng-Ft1),a small molecule,markedly inhibits subcutaneous tumor formation in CRC and enhances the proportion of CD8^(+)T cells in tumor-bearing mice,thus restraining tumor growth.Investigation into the mechanism revealed that Ng-Ft1 selectively targets the deubiquitination enzyme USP9X,undermining its role in shieldingβ-catenin.This leads to a reduction in the expression of downstream effectors in the Wnt signaling pathway.These findings indicate that Ng-Ft1 could be a promising small-molecule treatment for CRC,working by blocking tumor progression via the Wnt signaling pathway and augmenting CD8^(+)T cell prevalence within the tumor environment.

A novel method for identifying SARS-CoV-2 infection mutants via an epitope-specific CD8^(+)T cell test

Since the outbreak of the coronavirus disease 2019(COVID-19)epidemic in 2019,the public health system has faced enormous challenges.Tracking the individuals who test positive for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)is a key step for interrupting chains of transmission of SARS-CoV-2 and reducing COVID-19-associated mortality.With the increasing of asymptomatic infections,it is difficult to track asymptomatic infections through epidemiological surveys and virus whole-genome sequencing.However,due to the cross-reactivity of neutralizing antibodies produced by multiple virus subtypes,neutralizing antibody detection cannot be used to determine whether an individual has a history of infection with a specific subtype of SARS-CoV-2.We recruited 4 human leukocyte antigen A2(HLA-A2)infections,15 individuals who received three doses of inactivated vaccines,and 30 breakthrough infections after vaccination and discussed a case-tracking approach to detect epitope-specific CD8^(+)T cells in the peripheral blood of close contacts,including accurate HLA typing based on ribonucleic acid(RNA)-sequencing and flow cytometry data and the comparison and characterization of SARS-CoV-2 HLA-A2 and HLA-A24 epitope-specific CD8^(+)T cells.From individuals who received three doses of inactivated vaccine,we observed that the CD8^(+)T cell specificity for ancestral epitopes was significantly higher than for mutated epitopes,and the fold change of CD8^(+)T cells corresponding to mutated epitopes relative to ancestral epitopes was less than 1.The enzyme-linked immunospot(ELISpot)results further validate this result.This study forms a“method for understanding the infection history of SARS-CoV-2 subtypes based on the proportion of epitope-specific CD8^(+)T cells in the peripheral blood of subjects”,covering up to 46%of the population,including HLA-A2+and HLA-A24+donors,providing a novel method for SARS-CoV-2 infected case tracing.

X-ray irradiation selectively kills thymocytes of different stages and impairs the maturation of donor-derived CD4^+CD8^+ thymocytes in recipient thymus

The aim of the present study was to determine whether the sensitivity of thymocytes to X-ray radiation depends on their proliferative states and whether radiation impairs the maturation of donor-derived thymocytes in recipient thymus.We assigned 8-week-old C57BL/6J mice into three treatment groups：1） untreated;2） X-ray radiation;3） X-ray radiation plus bone marrow transplantation with donor bone marrow cells from transgenic mice express-ing enhanced green fluorescent protein（GFP） on a universal promoter.After 4 weeks,the size of the thymus,the number and proliferation of thymocytes and ratios of different stage thymocytes were analyzed by immunohisto-chemistry and flow cytometry.The results showed that：1） CD4＋CD8＋ thymocytes were more sensitive to X-ray radiation-induced cell death than other thymocytes;2） the proliferative capacity of CD4＋CD8＋ thymocytes was higher than that of other thymocytes;3） the size of the thymus,the number of thymocytes and ratios of thymo-cytes of different stages in irradiated mice recovered to the normal level of untreated mice by bone marrow trans-plantation;4） the ratio of GFP-positive CD4＋CD8＋ thymocytes increased significantly,whereas the ratio of GFP-positive CD4＋ or CD8＋ thymocytes decreased significantly.These results indicate that the degree of sensitivity of thymocytes to X-ray radiation depends on their proliferative states and radiation impairs the maturation of donor-derived CD4＋CD8＋ thymocytes in recipient thymus.

Changing roles of CD3^(+)CD8^(low) T cells in combating HIV-1 infection

Background:Cluster of differentiation 8(CD8 T)cells play critical roles in eradicating human immunodeficiency virus(HIV)-1 infection,but little is known about the effects of T cells expressing CD8 at low levels(CD8^(low))or high levels(CD8^(high))on HIV-1 replication inhibition after HIV-1 invasion into individual.Methods:Nineteen patients who had been acutely infected with HIV-1(AHI)and 20 patients with chronic infection(CHI)for≥2 years were enrolled in this study to investigate the dynamics of the quantity,activation,and immune responses of CD3^(+)CD8^(low) T cells and their counterpart CD3^(+)CD8^(high) T cells at different stages of HIV-1 infection.Results:Compared with healthy donors,CD3^(+)CD8^(low) T cells expanded in HIV-1-infected individuals at different stages of infection.As HIV-1 infection progressed,CD3^(+)CD8^(low) T cells gradually decreased.Simultaneously,CD3^(+)CD8^(high) T cells was significantly reduced in the first month of AHI and then increased gradually as HIV-1 infection progressed.The classical activation of CD3^(+)CD8^(low) T cells was highest in the first month of AHI and then reduced as HIV-1 infection progressed and entered the chronic stage.Meanwhile,activated CD38^(-)HLA-DR^(+)CD8^(low) T cells did not increase in the first month of AHI,and the number of these cells was inversely associated with viral load(r=-0.664,P=0.004)but positively associated with the CD4 T-cell count(r=0.586,P=0.014).Increased programmed cell death protein 1(PD-1)abundance on CD3^(+)CD8^(low) T cells was observed from the 1st month of AHI but did not continue to be enhanced,while a significant T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif(ITIM)domains(TIGIT)abundance increase was observed in the 12th month of infection.Furthermore,increased PD-1 and TIGIT abundance on CD3^(+)CD8^(low) T cells was associated with a low CD4 T-cell count(PD-1:r=-0.456,P=0.043;TIGIT:r=-0.488,P=0.029)in CHI.Nonetheless,the nonincrease in PD-1 expression on classically activated CD3^(+)CD8^(low) T cells was inversely associated with HIV-1 viremia in the first month of AHI(r=-0.578,P=0.015).Notably,in the first month of AHI,few CD3^(+)CD8^(low) T cells,but comparable amounts of CD3^(+)CD8^(high) T cells,responded to Gag peptides.Then,weaker HIV-1-specific T-cell responses were induced in CD3^(+)CD8^(low) T cells than CD3^(+)CD8^(high) T cells at the 3rd and 12th months of AHI and in CHI.Conclusions:Our findings suggest that CD3^(+)CD8^(low) T cells play an anti-HIV role in the first month of infection due to their abundance but induce a weak HIV-1-specific immune response.Subsequently,CD3^(+)CD8^(low) T-cell number decreased gradually as infection persisted,and their anti-HIV functions were inferior to those of CD3^(+)CD8^(high) T cells.

Sialic acid-mediated photochemotherapy enhances infiltration of CD8^(+)T cells from tumor-draining lymph nodes into tumors of immunosenescent mice

Immunoscenescence plays a key role in the initiation and development of tumors.Furthermore,immunoscenescence also impacts drug delivery and cancer therapeutic efficacy.To reduce the impact of immunosenescence on anti-tumor therapy,this experimental plan aimed to use neutrophils with tumor tropism properties to deliver sialic acid(SA)-modified liposomes into the tumor,kill tumor cells via SA-mediated photochemotherapy,enhance infiltration of neutrophils into the tumor,induce immunogenic death of tumor cells with chemotherapy,enhance infiltration of CD8^(+)T cells into the tumordraining lymph nodes and tumors of immunosenescent mice,and achieve SA-mediated photochemotherapy.We found that CD8^(+)T cell and neutrophil levels in 16-month-old mice were significantly lower than those in 2-and 8-month-old mice;16-month-old mice exhibited immunosenescence.The anti-tumor efficacy of SA-mediated non-photochemotherapy declined in 16-month-old mice,and tumors recurred after scabbing.SA-mediated photochemotherapy enhanced tumor infiltration by CD8^(+)T cells and neutrophils,induced crusting and regression of tumors in 8-month-old mice,inhibited metastasis and recurrence of tumors and eliminated the immunosenescence-induced decline in antitumor therapeutic efficacy in 16-month-old mice via the light-heat-chemical-immunity conversion.

The OX40-TRAF6 axis promotes CTLA-4 degradation to augment antitumor CD8^(+)T-cell immunity

Immune checkpoint blockade(ICB),including anti-cytotoxic T-lymphocyte associated protein 4(CTLA-4),benefits only a limited number of patients with cancer.Understanding the in-depth regulatory mechanism of CTLA-4 protein stability and its functional significance may help identify ICB resistance mechanisms and assist in the development of novel immunotherapeutic modalities to improve ICB efficacy.Here,we identified that TNF receptor-associated factor 6(TRAF6)mediates Lys63-linked ubiquitination and subsequent lysosomal degradation of CTLA-4.Moreover,by using TRAF6-deficient mice and retroviral overexpression experiments,we demonstrated that TRAF6 promotes CTLA-4 degradation in a T-cell-intrinsic manner,which is dependent on the RING domain of TRAF6.This intrinsic regulatory mechanism contributes to CD8+T-cell-mediated antitumor immunity in vivo.Additionally,by using an OX40 agonist,we demonstrated that the OX40-TRAF6 axis is responsible for CTLA-4 degradation,thereby controlling antitumor immunity in both tumor-bearing mice and patients with cancer.Overall,our findings demonstrate that the OX40-TRAF6 axis promotes CTLA-4 degradation and is a potential therapeutic target for the improvement of T-cell-based immunotherapies.

Berberine improves central memory formation of CD8^(+)T cells:Implications for design of natural product-based vaccines

Berberine(BBR)as one of the most effective natural products has been increasingly used to treat various chronic diseases due to its immunosuppressive/tolerogenic activities.However,it is unknown if BBR can be applied without abrogating the efforts of vaccination.Here we show that priming of CD8^(+)T cells in the presence of BBR lead to improved central memory formation(Tcm)with substantially reduced effector proliferation,primarily orchestrated through activation of AMPK and Stat5.Tcm derived from vaccinated mice fed with BBR were able to adoptively transfer protective immunity to naIve recipients.Vaccination of BBR-fed mice conferred better memory protection against infection without losing immediate effector efficacy,suggesting appreciable benefits from using BBR in vaccination.Thus,our study may help to lay the groundwork for mechanistic understanding of the immunomodulatory effects of natural products and their potential use as adjuvant that allows the design of novel vaccines with more desirable properties.

IGF2BP3 Enhances the Growth of Hepatocellular Carcinoma Tumors by Regulating the Properties of Macrophages and CD8^(+)T Cells in the Tumor Microenvironment

Background and Aims:Overexpression of IGF2BP3 is associated with the prognosis of hepatocellular carcinoma(HCC).However,its role in regulating tumor immune microenvironment(TME)is not well characterized.Here,we investigated the effects of IGF2BP3 on macrophages and CD8^(+)T cells within the TME of HCC.Methods:The relationship between IGF2BP3 and immune cell infiltration was analyzed using online bioinformatics tools.Knockout of IGF2BP3 in mouse hepatoma cell line Hepa1-6 was established using CRISPR/Cas9 technology.In vitro cell coculture and subcutaneously implanted hepatoma mice model were used to explore the effects of IGF2BP3 on immune cells.Expression of CCL50l transforming growth factor beta 1(TGF-β1)was detected with quantitative real-time polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay.The binding of IGF2BP3 and its target RNA was verified by trimolecular fluorescence complementation system and RNA immunoprecipitation followed by quantitative or semiquantitative polymerase chain reaction.Results:IGF2BP3 expression was elevated in HCC and was positively correlated with macrophage infiltration.Patients with higher IGF2BP3 expression and lower macrophage infiltration had a better survival rate.We found that IGF2BP3 could bind to the mRNA of CCL5 or TGF-β1,increasing their expression,and inducing macrophage infiltration and M2 polarization while inhibiting the activation of CD8^(+)T cells.Furthermore,inhibition of IGF2BP3 combined with anti-CD47 antibody treatment significantly suppressed the growth of hepatoma in Hepa1-6 xenograft tu-mor mice.Conclusions:IGF2BP3 promoted the infiltration and M2-polarization of macrophages and suppressed CD8^(+)T activation by enhancing CCL5 and TGF-β1 expression,which facilitated the progression of Hepa1-6 xenograft tumor.

Mettl3依赖的m^(6)A甲基化调控CD8^(+)T细胞效应分化和记忆形成

Efficient immune responses rely on the proper differentiation of CD8^(+)T cells into effector and memory cells.Here,we show a critical requirement of N^6-Methyladenosine(m^(6)A)methyltransferase Mettl3 during CD8^(+)T cell responses upon acute viral infection.Conditional deletion of Mettl3 in CD8^(+)T cells impairs effector expansion and terminal differentiation in an m^(6)A-dependent manner,subsequently affecting memory formation and the secondary response of CD8^(+)T cells.Our combined RNA-seq and m^(6)AmiCLIP-seq analyses reveal that Mettl3 deficiency broadly impacts the expression of cell cycle and transcriptional regulators.Remarkably,Mettl3 binds to the Tbx21 transcript and stabilizes it,promoting effector differentiation of CD8^(+)T cells.Moreover,ectopic expression of T-bet partially restores the defects in CD8^(+)T cell differentiation in the absence of Mettl3.Thus,our study highlights the role of Mettl3 in regulating multiple target genes in an m^(6)A-dependent manner and underscores the importance of m^(6)A modification during CD8^(+)T cell response.

Research progress on the role of immune cells in Brucella infection

Brucellosis is one of the most prevalent zoonoses in the world. Incidence of the disease has increased significantly in recent years and has seriously affected the health of human beings and the development of animal husbandry. The pathogenesis of brucellosis remains unclear. Current studies suggest that this disease may be related to changes in natural killer cells, dendritic cells, and macrophages in immune cell subsets. Brucellosis may be also related to T helper(Th) 1 cell/Th2 cell imbalance in the CD4^+ T cell subset, immunoregulation of regulatory T cells and Th17 cells, and the mechanism of action of CD8^+ T cell. This paper aims to review the research progress on these inherent immune cells, the CD4^+ T cell subset, and CD8^+ T cells in Brucella infection.