Research on the effects of CD137 signaling on the function of CD3^-CD56^+NK cells

Objective： To investigate the effects of CD137 signaling on the regulation of CD3-CD56＋NK cells function. Methods： CD3 CD56＋NK cells were treated with CD137 mAb or mouse IgG 1 isotype control to study the effects of CD 137 signaling on the function of CD3-CD56＋NK cells. Cytotoxicity was measured by LDH activity in the supernatants of cell cultures; NKG2D and LFA-I expression on CD3-CD56＋NK cells were analyzed by flow cytometry. Results： CD137 was expressed on activated CD3-CD56＋NK cells. The CD137 mAb enhanced the ability of CDB-CD56＋NK cells to kill lung cancer cells（A549）; Further studies revealed that the expression of NKG2D and LFA-1 was significantly increased in activated cells, and blockade of NKG2D and LFA-1 dramatically attenuated CD3CD56＋NK cytolysis of A549 cancer cells. Conclusion： CD 137 signaling increases the ability of CD3-CD56＋NK cells to kill cancer cells via up- regulating the expression of NKG2D and LFA-1.

Analysis of CD4^+CD25^+ Regulatory T Cells and Foxp3 mRNA in the Peripheral Blood of Patients with Asthma

The changes of CD4^＋CD25^＋ regulatory T cells （CD4^＋CD25^＋ Treg） and Foxp3 mRNA in peripheral blood mononuclear cells （PBMCs） from patients with asthma were investigated in order to elucidate the possible roles of CD4^＋CD25^＋ Treg in the development of asthma. The peripheral blood samples were collected from 29 healthy controls （normal control group） and 78 patients with asthma which included 30 patients in exacerbation group, 25 patients in persistent group, and 23 patients in remission group. By using flow cytometry and RT-PCR, the CD4^＋CD25^＋ Treg ratio and Foxp3 mRNA in PBMCs were detected. The CD4^＋CD25^＋ Treg ratio and Foxp3 mRNA in PBMCs of exacerbation and persistent groups were lower than that of remission and normal control groups （P〈0.05）. Although the CD4^＋CD25^＋ Treg ratio and Foxp3 mRNA of remission group were also lower than that of normal control group, there was no significant difference between them （P〉0.05）. As compared with persistent group, exacerbation group had lower CD4^＋CD25^＋ Treg ratio and Foxp3 mRNA （P〈0.05）. It was indicated that the decrease of CD4^＋CD25^＋ Treg ratio and its function in PBMCs may be responsible for pathogenesis of asthma.

All-transRetinoic Acid Regulates Th1/Th2 Balance in CD4+T cells When GATA-3 is Deficient

The essential effect of vitamin A on immune function occurs through various mechanisms including direct effect on ThloTh2 balance modulation. However, it is unclear whether or not vitamin A can regulate Thl-Th2 balance under a strong Thl-polarizing condition. Therefore, the purpose of our study was to examine the effect of vitamin A metabolite allotrans retinoic acid （ATRA） on ThloTh2 differentiation in CD4~ T cells under GATA-3 deficiency, which can induce Thl-polarizing condition. In the present study, GATA-3 deficiency T cells were induced by siRNA and checked by real-time quantitative PCR and western blot. GATA-3 deficiency CD4＋ T cells and normal CD4＋ T were treated for 48 h with or without ATRA.

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.

Immunotherapy of rat glioma without accumulation of CD4^+CD25^+FOXP3^+ regulatory T cells

Immunotherapy may be used for the treatment of glioblastoma multiforme; however, the induced immune response is inadequate when either T cells or dendritic cells are used alone. In this study we established a novel vaccine procedure in rats, using dendritic cells pulsed with C6 tumor cell lysates in combination with adoptive transfer of T lymphocytes from syngenic donors. On day 21 after tumor inoculation, all the rats were sacrificed, the brains were harvested for calculation of glioma volume, cytolytic T lymphocyte responses were measured by cytotoxic assay, and the frequency of regulatory T lymphocytes （CD4＋CD25~FOXP3~） in the peripheral blood was investigated by flow cytometric analysis. The survival rate of rats bearing C6 glioma was observed. Results showed that the co-immunization strategy had significant anti-tumor potential against the pre-established C6 glioma, and induced a strong cytolytic T lymphocyte response in rats. The frequency of peripheral blood CD4＊CD25＊FOXP3＊ regulatory T lymphocytes was significantly decreased following the combination therapy, and the rats survived for a longer period. Experimental findings indicate that the combined immunotherapy of glioma cell lysate-pulsed dendritic cell vaccination following adoptive transfer of T cells can effectively inhibit the growth of gliomas in rats, boost anti-tumor immunity and produce a sustained immune response while avoiding the accumulation of CD4＋CD25＋FOXP3＋ regulatory r lymphocytes.

Rapamycin increased development of CD4^+ CD25~h ighFoxp3^+ T cells of peripheral blood in liver transplant recipients

Objective To investigate the possible influence of immunosuppressive therapy,including sirolimus ( SRL) and calcineurin inhibitors ( CNI,tacrolimus) ,on level of Treg in liver allo - graft recipients. Methods Forty - seven liver transplant recipients with stable liver function were assessed for at least 2 years,and divided into

Effect of CD4^+CD25^+ regulatory T cells in the development of anterior chamber-associated immune deviation

AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)D25(+) T cells, CD4(+)D25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells from spleens of mice with ACAID were analyzed by flow cytometry. Foxp3 mRNA expression in purified CD4(+)CD25(+) T cells was analyzed using real-time PCR. The suppressive effect of purified CD4(+)CD25(+) T cells on the proliferation of CD4(+)CD25(-) T cells was evaluated by [H-3] thymidine incorporation. A blocking experiment was performed to further address the role of CD4(+)CD25(+) T cells in ACAID. The expression of IL-10 in purified CD4(+)CD25(+) T cells was evaluated by ELISA. RESULTS: Increased frequencies of CD4(+)CD25(+) T cells, CD4(+)CD25(+) Foxp3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells were observed in ACAID. The CD4(+)CD25(+) T cells from mice with ACAID showed enhanced suppressive effect on the proliferation of CD4(+)CD25(-) T cells. Treatment of BALB/c mice with anti-CD25 antibody after injection of OVA into the anterior chamber significantly inhibited the induction of ACAID. Furthermore, purified CD4(+)CD25(+) T cells from ACAID mice secreted IL-10. CONCLUSION: Our results demonstrate that Treg cells are induced in the mice undergoing ACAID. These Treg cells may play a role in the development of ACAID.

Full T-cell activation and function in teleosts require collaboration of first and co-stimulatory signals

Mammalian T-cell responses require synergism between the first signal and co-stimulatory signal.However,whether and how dual signaling regulates the T-cell response in early vertebrates remains unknown.In the present study,we discovered that the Nile tilapia(Oreochromis niloticus)encodes key components of the LAT signalosome,namely,LAT,ITK,GRB2,VAV1,SLP-76,GADS,and PLC-γ1.These components are evolutionarily conserved,and CD3εmAb-induced T-cell activation markedly increased their expression.Additionally,at least ITK,GRB2,and VAV1 were found to interact with LAT for signalosome formation.Downstream of the first signal,the NF-κB,MAPK/ERK,and PI3K-AKT pathways were activated upon CD3εmAb stimulation.Furthermore,treatment of lymphocytes with CD28 mAbs triggered the AKT-mTORC1 pathway downstream of the co-stimulatory signal.Combined CD3εand CD28 mAb stimulation enhanced ERK1/2 and S6 phosphorylation and elevated NFAT1,c-Fos,IL-2,CD122,and CD44 expression,thereby signifying T-cell activation.Moreover,rather than relying on the first or co-stimulatory signal alone,both signals were required for T-cell proliferation.Full T-cell activation was accompanied by marked apoptosis and cytotoxic responses.These findings suggest that tilapia relies on dual signaling to maintain an optimal T-cell response,providing a novel perspective for understanding the evolution of the adaptive immune system.

THE DETECTION OF CD56 AND EPSTEIN-BARR VIRUS IN T-CELL LYMPHOMAS

Objective: To study the relationship between EBV infection and the expression of CD56 in T cell lymphomas (TCLs). Methods: 46 cases of TCLs and 15 cases of reactive hyperplasia of lymphonodes (RHs) were detected CD56 by immunohistochemistry and EBERs by in situ hybridization. Results: 8 cases of 46 TCLs (17.4%) showed CD56 positive. On sites, CD56 positive rate of nasopharyngeal TCLs was highest (5/17, 29.4%), and on subtypes, that of DLs was highest (6/16, 37.5%). Additionally, 4 RHs were also CD56 positive. Of 46 TCLs, 24 showed expression of EBERs. There were only 4 TCLs expressing both CD56 and EBERs. Conclusion: The expression of CD56 was not especially for TCLs that EBV infected. EBV infection was not related with CD56 positive TCLs. The findings also suggested the expression of CD56 in TCLs be possibly related to original sites and subtypes of TCLs.

Effect of macrophage polarization regulated by miR-29b,B7H3 on CD4^(+)T cell differentiation in asthma

Objective:To explore the mechanism that miR-29b and B7H3 regulate the polarization of macrophages and thus affect the differentiation of CD4^(+)T.Methods:1.PBMC was extracted from peripheral blood mononuclear cells of children with asthma and normal children in the affiliated Children's Hospital of Soochow University,and RNA was extracted and reverse transcribed.The expression of miR-29b and B7H3mRNA was determined by real-time quantitative polymerase chain reaction(Q-PCR).The family history of asthma and history of allergic diseases were collected.2.THP-1 cells were induced into macrophages,miR-29b interference,miR-29b overexpression and normal control were induced by LV526,LV527 and NC virus infection.After 24 hours of culture,the cells were collected to detect the expression of STAT3 and B7H3 genes and proteins.3.It was verified that STAT3 was the target gene of miR-29b:after inoculating THP-1 cells and culturing with PMA with final concentration of 50ng/ml for 6 hours,the macrophages without PMA were cultured for 24 hours,then the macrophages infected by LV528,LV529 and NC virus were induced to form miR-29b interference,miR29b overexpression and normal control group.Luciferase analysis was performed at 48 hours to verify that STAT3 was the target gene of miR-29b.STAT3-3'UTR luciferase reporter gene plasmids were constructed and divided into three groups:"miR-29b+STAT3-3'UTR","miR-29b+STAT3-mut-3'UTR"and"miR-29b+luciferase empty load".4.Macrophages with different treatments were co-cultured with initial T cells for 3 days.The relative expressions of T-bet,GATA3 and ROR-γt were detected by Q-PCR.Result:1.The incidence of allergic disease in the acute attack group(68%)was higher than that in the other two groups(34.8%,33.3%),and the family history of asthma in the normal group(0%)was much lower than that in the other two groups(52%,60.9%).The difference was statistically significant(P<0.05).2.The expression of B7H3 in PBMC in acute attack group was higher than that in non-acute attack group and normal group.The expression of miR-29b in PBMC in normal group was significantly higher than that in non-acute attack group and acute attack group(P<0.0001).The expression of miR-29b in non-acute attack group was significantly higher than that in acute attack group(P=0.007).3.After silencing the expression of miR-29b,IL-4Rα,IL-4,IL-5,IL-13 and CD206 of macrophages increased significantly,while IFN-γdecreased,suggesting that miR-29b can promote the polarization of macrophages to M2.4.The overexpression of miR-29b,STAT3 and B7H3 gene and protein level in macrophages decreased,while the increase of miR-29b,STAT3 and B7H3 gene and protein expression was inhibited.5.There was a significant positive correlation between the expression of STAT3 and B7H3mRNA in macrophages(r=0.9737,P<0.0001).6.STAT3 is the target gene of miR-29b.7.Co-culture of macrophages with CD4^(+)T cells can promote the differentiation of primary T cells,namely Th 0 cells,into Th2,and the promoting effect of macrophages with downregulation of miR-29b is more obvious.Conclusion:The expression of miR-29b in PBMC of children with asthma is lower than that of normal children,while the expression of B7H3 is higher than that of normal children.It is speculated that miR-29b has a protective effect on children with asthma,while B7H3 aggravates the inflammatory response.Down-regulation of miR-29b,in macrophages can promote macrophages to M2 polarization,increase the expression of B7H3 and STAT3 in macrophages,make Th0 cells differentiate into Th2 cells,and aggravate the inflammatory response in patients with asthma.

Sustained heavy ethanol drinking affects CD4⁺cell counts in HIV-infected patients on stavudine (d4T), lamivudine (3TC) and nevirapine (NVP) treatment regimen during 9 months follow-up period

Sustained heavy ethanol drinking is a common problem globally and ethanol is one of the most abused drugs among individuals of different socio-economic status including the HIV-infected patients on antiretroviral drugs. Ethanol is reward drug and a CNS depressant especially at high doses. The study determined the effect of sustained heavy ethanol drinking by HIV-infected patients on d4T/3TC/NVP regimen on CD4+ cell counts in Uganda using WHO AUDIT tool and chronic alcohol-use biomarkers. A case control study using repeated measures design with serial measurements model was used. The patients on stavudine (d4T) 30 mg, lamivudine (3TC) 150 mg and nevirapine (NVP) 200 mg and chronic alcohol use were recruited. A total of 41 patients (20 in alcohol group and 21 in control group) were screened for chronic alcohol use by WHO AUDIT tool and chronic alcohol use biomarkers. They were followed up for 9 months with blood sampling done at 3 months intervals. CD4+ cell count was determined using Facscalibur Flow Cytometer system. Results were then sorted by alcohol-use biomarkers (GGT, MCV and AST/ ALT ratio). Data were analysed using SAS 2003 version 9.1 statistical package with repeated measures fixed model and the means were compared using student t-test. The mean CD4+ cell counts in all the groups were lower than the reference ranges at baseline and gradually increased at 3, 6 and 9 months of follow-up. The mean CD4+ cell counts were higher in the control group as compared to the chronic alcohol use group in both WHO AUDIT tool group and chronic alcohol-use biomarkers group though there was no significant difference (p > 0.05). Chronic alcohol use slightly lowers CD4+ cell count in HIV-infected patients on d4T/3TC/NVP treatment regimen.

间变性大细胞性T细胞性淋巴瘤中EB病毒检测及CD_(56)的表达

目的：研究间变性大细胞性Ｔ细胞性淋巴瘤（ａｎａｐｌａｓｔｉｃｌａｒｇｅＴｃｅｌｌｙｍｐｈｏｍａ，ＡＬＴＣＬ）ＥＢ病毒表达情况及其与ＣＤ５６阳性表达间的关系。方法：采用免疫组织化学ＬＳＡＢ法检测１５例ＡＬＴＣＬ中Ｋｉ１及ＣＤ５６的表达，并用原位杂交法检测其ＥＢＥＲｓ。结果：１５例ＡＬＴＣＬ中Ｋｉ１均阳性（１００％），５例ＣＤ５６阳性（３３３％），９例ＥＢＥＲｓ阳性。其中，３例ＡＬＴＣＬ中ＥＢＥＲｓ和ＣＤ５６共同阳性。结论：ＡＬＴＣＬ的发生同ＥＢ病毒感染有一定关系；部分ＡＬＴＣＬ中有ＣＤ５６阳性表达，ＥＢ病毒是否感染ＡＬＴＣＬ同ＣＤ５６表达无关。

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.

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.

Aberrant expression of CD56 by circulating Sézary syndrome malignant T lymphocytes

Sézary syndrome(SS) is an aggressive variant of cutaneous T cell lymphoma characterized by the presence of malignant T cells in the skin, peripheral blood and lymph nodes. The tumoral population typically displays a CD3+ CD4+ CD45RO+ memory T cell phenotype. We report a case of SS with an aberrant CD56+ immunophenotype. This patient presented with a generalized erythroderma and palpable small axillary lymph nodes.SS(stage IVA) was diagnosed on histological criteria and by the detection of a major T cell clone in skin and blood, an elevated CD4/CD8 T cell ratio and Sézary cells count > 1000/mm3. Beside the Sézary cell marker KIR3DL2, immunostainings revealed that two third of the malignant cells expressed CD56 but no other natural killer(NK) cell marker such as CD16, CD160 or NKp46. This atypical expression was not linked to an activation-dependent process and remained stable during the time course of the disease. No loss of the panT-cell markers CD2, CD3 or CD4 was detected while a complete down-modulation of CD26 was observed. Despite several lines of treatment, no durable amelioration was observed and patient died after 10 mo of follow-up. Because this CD4+ CD56+ SS case is the only one reported so far, the functional significance of CD56 expression remained difficult to assess in terms of aggressiveness and prognosis.

Blockade of Tim-3 Pathway Ameliorates Interferon-γ Production from Hepatic CD8^+ T Cells in a Mouse Model of Hepatitis B Virus Infection

T cell immunoglobulin- and mucin-domain-containing molecule-3 （Tim-3） has been reported to participate in the pathogenesis of inflammatory diseases. However, whether Tim-3 is involved in hepatitis B virus （HBV） infection remains unknown. Here, we studied the expression and function of Tim-3 in a hydrodynamics-based mouse model of HBV infection. A significant increase of Tim-3 expression on hepatic T lymphocytes, especially on CD8^＋ T cells, was demonstrated in HBV model mice from day 7 to day 18. After Tim-3 knockdown by specific shRNAs, significantly increased IFN-γ production from hepatic CD8^＋ T cells in HBV model mice was observed. Very interestingly, we found Tim-3 expression on CD8^＋ T cells was higher in HBV model mice with higher serum anti-HBs production. Moreover, Tim-3 knockdown influenced anti-HBs production in vivo. Collectively, our data suggested that Tim-3 might act as a potent regulator of antiviral T-cell responses in HBV infection. Cellular ＆ Molecular Immunology.

CD56^brightCD25^＋ NK cells are preferentially recruited to the maternal/fetal interface in early human pregnancy

Decidual natural killer （dNK） cells are believed to be critical for maintaining maternal/fetal tolerance and regulating placental vascular remodeling based upon their abundance and unique phenotype during early pregnancy. However, the mechanism for how the dNK cells play such important roles in successful pregnancy remains undefined. Here, we identified a subtype of dNK cells characterized as having a CD3-CD56^brightCD25^＋ phenotype. We found that CD56^brightCD25^＋ NK cells preferentially localize to the maternal/fetal interface during early human pregnancy. CD25^＋ dNK cells account for approximately 75% of CD25-expressing decidual immune cells （DICs）. However, less than 5% of CD25-positive peripheral blood mononuclear cells are CD25^＋ NK cells. Furthermore, CD25^＋ and CD25^- dNK cells exhibit distinct phenotypes： CD25^＋ dNK cells display a more activated phenotype and greater cytokine-secreting capacity. Interestingly, coculture of peripheral NK （pNK） cells with primary trophoblasts upregulates the percentage of CD25-expressing pNK cells, resulting in increased expression of activation markers and cytokine production by pNK cells. In addition, we demonstrated that the CXCL12/CXCR4 axis is crucial for the recruitment of CD25^＋ dNK cells and contributes to the accumulation of CD3^-CD56^brightCD25^＋ dNK cells at the maternal/fetal interface. Thus, our data reveal that the crosstalk between trophoblasts and pNK cells leads to the accumulation of CD3^-CD56^brightCD25^＋ dNK cells, which exert a regulating effect at the maternal/fetal interface.

Alterations of peripheral CD4^(+)CD25^(+)Foxp3^(+)T regulatory cells in mice with STZ-induced diabetes

Complications arising from abnormal immune responses are the major causes of mortality and morbidity in diabetic patients.CD4^(+)CD25^(+)T regulatory cells(Tregs)play pivotal roles in controlling immune homeostasis,immunity and tolerance.The effect of hyperglycemia on CD4^(+)CD25^(+)Tregs has not yet been addressed.Here we used streptozotocin(STZ)-induced diabetic mice to study the effects of long-term hyperglycemia on CD4^(+)CD25^(+)Tregs in vivo.Four months after the onset of diabetes,the frequency of CD4^(+)CD25^(+)Foxp3^(+)T regulatory cells was significantly elevated in the spleen,peripheral blood lymphocytes(PBLs),peripheral lymph nodes(pLNs)and mesenteric LNs(mLNs).CD4^(+)CD25^(+)Tregs obtained from mice with diabetes displayed defective immunosuppressive functions and an activated/memory phenotype.Insulin administration rescued these changes in the CD4^(+)CD25^(+)Tregs of diabetic mice.The percentage of thymic CD4^(+)CD25^(+)naturally occurring Tregs(nTregs)and peripheral CD41Helios1Foxp31 nTregs were markedly enhanced in diabetic mice,indicating that thymic output contributed to the increased frequency of peripheral CD4^(+)CD25^(+)Tregs in diabetic mice.In an in vitro assay in which Tregs were induced fromCD4^(+)CD25^(+)T cells by transforming growth factor(TGF)-b,high glucose enhanced the efficiency of CD4^(+)CD25^(+)Foxp3^(+)T inducible Tregs(iTregs)induction.In addition,CD4^(+)CD25^(+)T cells from diabetic mice were more susceptible to CD4^(+)CD25^(+)Foxp3^(+)TiTreg differentiation than those cells from control mice.These data,together with the enhanced frequency of CD4^(+)CD25^(+)Foxp3^(+)T iTregs in the periphery of mice with diabetes,indicate that enhanced CD4^(+)CD25^(+)Foxp3^(+)T iTreg induction also contributes to a peripheral increase in CD4^(+)CD25^(+)Tregs in diabetic mice.Our data show that hyperglycemia may alter the frequency of CD4^(+)CD25^(+)Foxp3^(+)T Tregs in mice,which may result in late-state immune dysfunction in patients with diabetes.

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.

Altered Carcinoembryonic Antigen-Related Cell Adhesion Molecule 1/T-Cell Immunoglobulin Mucin-3 Signaling Causes the Dysregulation of Decidual CD8+T Cells in the Third Trimester during Preeclamptic Pregnancies

Objective:To investigate the frequency and function of Tim-3^(+)CD8^(+)T cells in the third trimester of normal pregnancies(NPs)and preeclamptic(PE)pregnancies.Methods:T-cell immunoglobulin mucin-3(Tim-3)expression levels of CD8^(+)T cells in the decidua,peripheral blood,and umbilical cord blood obtained from women showing NPs and PE pregnancies were analyzed using flow cytometry.Decidual CD8^(+)T cells were cultured in the presence of recombinant human carcinoembryonic antigen-related cell adhesion molecule 1(CEACAM1)protein and/or Tim-3-specific neutralizing antibodies for analyzing CD107a and intracellular cytokine expression.The placental CEACAM1 protein expression was analyzed using immunohistochemistry.Results:Tim-3^(+)CD8^(+)T cells were more abundant in the decidua than in the peripheral blood.Tim-3 expression in the decidual CD8^(+)T cells was significantly lower in PE patients.Decidual Tim-3^(+)CD8^(+)T cells from PE patients expressed higher levels of CD107a and the Th1-type cytokine IFN-γ,but lower levels of the Th2-type cytokine IL-4.CEACAM1 altered the CD107a,IFN-γ,and IL-4 levels;this was reversed by anti-Tim-3 antibodies.The CEACAM1 protein levels were lower in the placental tissues of women with PE pregnancies than in those of women with NPs.Conclusions:Abnormal CEACAM1/Tim-3 regulation may participate in the development of PE,accompanied by disturbed Th2 cell predominance and higher cytotoxicity of decidual CD8^(+)T cells.