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 naïve 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.

Value of dynamic monitoring of absolute value and function of peripheral blood lymphocyte subsets in predicting the risk of early viral infection after kidney transplantation / 器官移植

Objective To investigate the predictive and diagnostic value of absolute value and function of different lymphocyte subsets in evaluating the risk of early viral infection after kidney transplantation. Methods Ninety-five kidney transplant recipients were enrolled in this prospective observational cohort study, and divided into the stable group (n=77) and infection group (n=18) according to postoperative immune status. Peripheral blood samples were collected for flow cytometry before operation, and 2 weeks, 1 month, 2 months and 6 months after operation. The dynamic changes of the absolute values of CD4+T cells, CD8+T cells and natural killer (NK) cells were compared between two groups. The function of lymphocyte subsets in two groups was evaluated by detecting the proportion of interferon (IFN)-γ+CD4+T cells, IFN-γ+CD8+T cells and IFN-γ+NK cells. The value of the absolute values and function of lymphocyte subsets in predicting and diagnosing viral infection in the early stage after kidney transplantation was evaluated. Results During viral infection, the absolute values of CD4+T cells, CD8+T cells and NK cells in the infection group were at a relatively low level. At 2 months after operation, the absolute values of CD4+T cells and NK cells in the infection group were lower than those in the stable group. At 6 months after operation, the absolute values of CD4+T cells and CD8+T cells in the infection group were significantly lower compared with those in the stable group (all P < 0.05). During viral infection, the proportion of IFN-γ+CD4+T cells, IFN-γ+CD8+T cells and IFN-γ+NK cells in the infection group were all at a relatively low level, especially that of IFN-γ+CD8+T cells decreased most significantly. At postoperative 2 months, the proportion of IFN-γ+CD8+T cells and IFN-γ+NK cells in the infection group was significantly higher than those in the stable group. At 6 months after operation, the proportion of IFN-γ+CD4+T cells and IFN-γ+CD8+T cells in the infection group was significantly higher than those in the stable group (all P < 0.05). Logistic regression analysis showed that the increasing proportion of IFN-γ+CD8+T cells and IFN-γ+NK cells was correlated with the increasing risk of viral infection at 2 months after operation (both P < 0.05). The receiver operating characteristic (ROC) curve demonstrated that the diagnostic value of absolute values of lymphocyte subsets combined with IFN-γ secretion function for viral infection in the immunocompromised recipients was significantly higher than that of absolute values of lymphocyte subsets alone (P < 0.05). Conclusions Dynamic monitoring of the changes of absolute values and function of lymphocyte subsets provides critical reference value for the prediction, diagnosis and medication guidance of viral infection.

Characteristics of CD8+ T cell infiltration in colorectal cancer and their correlation with prognosis / 中华胃肠外科杂志

Objective: As cytotoxic T cells, CD8+ T lymphocytes can kill tumor cells by releasing perforin and other effector molecules, but the correlation between their infiltration level and the prognosis of colorectal cancer varies in previous studies. This study aims to explore the distribution of CD8+T cells in tumor center and invasive margin of colorectal cancer, and to analyze their correlation with the prognosis of patients. Methods: A retrospective cohort study was used to analyze the clinicopathological features of 221 patients with colorectal cancer from the colorectal cancer pathological database of the Sixth Affiliated Hospital of Sun Yat-sen University between 2009 and 2012. Case inclusion criteria: (1) colorectal cancers confirmed by postoperative pathology; (2) patients with follow-up data. Exclusion criteria: (1) multiple primary cancers; (2) inflammatory bowel disease, Lynch syndrome or familial adenomatous polyposis; (3) no available paraffin slides; (4) patients receiving preoperative radiotherapy or chemotherapy. A total of 221 patients met the criteria. Immunohistochemical staining was used to count the CD8+ T cells in tumor center and invasive margin in the paraffin slides. Meanwhile the relative expression of CD8B gene in 22 fresh freeze samples of colorectal cancer was detected. Then the correlation of the expression with CD8+T cell density was examined. The patients were divided into high and low infiltration groups according to the level of CD8+T cells. Log-rank test was applied to compare the overall survival of the two groups of patients, and Cox regression analysis was used to adjust the prognostic significance of CD8+T cell infiltration. Results: There were 118 males and 103 females. In 221 slides, CD8+T cells infiltrating in invasive margin were more than those in tumor center [median (range): 37(0-141) / field vs. 14(0-106) / field, Z=-11.985, P<0.001], and the number of CD8+T cell in the tumor center was positively correlated with those in invasive margin (r=0.610, P<0.001). The number of CD8+ T cell in tumor center was positively correlated with the relative expression of CD8B gene (r=0.524, P=0.012). Survival analysis showed that the overall survival of the high infiltration group was better than that of the low infiltration group both in tumor center and invasive margin (median survival: 84.1 months vs. 73.5 months, P<0.001; 84.2 months vs. 75.9 months, P=0.002). Cox regression analysis revealed that high CD8+T cell infiltration in tumor center was an independent protective factor of overall survival (HR=0.369, 95% CI: 0.168-0.812, P=0.013). Conclusions: The infiltration level of CD8+T cells in tumor center is lower than that in invasive margin, and they are positively correlated. The level of CD8+ T cell infiltration in tumor center is related to overall survival and can be used as a potential pronostic marker.

Exhaustion of CD8 T cell immune functions in spleen of mice with different doses of Echinococcus multilocularis infections / 中国血吸虫病防治杂志

ObjectiveTo examine the changes in the immune functions of CD8+ T cells in the spleen of mice following Echinococcus multilocularis infections at various doses and at different time points. MethodsThe E. multilocularis protoscoleces were collected, and E. multilocularis infection was modeled in mice via the hepatic portal vein at doses of 50 (low-dose), 500 (medium-dose) and 2 000 protoscoleces (high-dose), while physiological saline served as controls. Mouse spleen was isolated 2 (earlystage), 12 (middle-stage) and 24 weeks post-infection (late-stage), and spleen lymphocytes were harvested. The phenotype of memory CD8+ T cells and 2B4 expression were quantified in the mouse spleen, and the secretion of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-17A and IL-10 was measured. Results A central-memory phenotype was predominant in the CD8+ T cells in the spleen of mice at the early stage of high-dose protoscolece infections, and the proportion of central-memory CD8+ T cells was significantly greater in the high-dose group than in the control group (35.50% ± 2.00% vs. 25.90% ± 2.46%, P < 0.01), while a effector- memory phenotype was predominant in the CD8+ T cells in the spleen of mice at the late stage of medium- and high-dose protoscolece infections, and the proportions of effector-memory CD8+ T cells were significantly greater in the medium- (25.70% ± 4.12%) and high-dose group (28.40% ± 4.12%) than in the control group (10.50% ± 6.45%) (P < 0.05). The proportions of the central-memory CD8+ T cells were significantly higher in the high-dose group than at middle and late stages than at the early stage (P < 0.01), and the proportion of effector-memory CD8+ T cells was significantly greater in the high-dose group at the late stage than at early and middle stages (P < 0.05). The secretion of IFN-γ and IL-17A by spleen CD8+ T cells was elevated in the low- and medium-dose groups at the early stage of infection, and high-dose protoscolece infection promoted the secretion of IFN-γ and TNF-α by spleen CD8+ T cells; however, the levels of IFN-γ and TNF-α were significantly lower at the late stage than at the early and middle stages (P < 0.05). In addition, high 2B4 expression was detected in spleen CD8+ T cells in the middle- and high-dose groups at the late stage of infection, and the 2B4 expression was significantly higher in the medium(4.73% ± 1.56%) and high-dose groups (4.94% ± 1.90%) than in the low-dose group (2.49% ± 0.58%) and the control group (2.92% ± 0.60%) (P < 0.05). Conclusions E. multilocularis may be killed and eliminated through the host immune responses at the middle and late stages of low- and medium-dose protoscolece infections, while high-dose protoscolece infections may trigger the upregulation of 2B4 expression in mouse spleen CD8+ T cells at the late stage, which leads to immune exhaustion and the resultant chronic infections.

Characteristics and prognostic value of peripheral blood T lymphocyte subsets in patients with severe influenza / 中华内科杂志

Objective@#To investigate the characteristics and prognostic value of peripheral blood T lymphocyte subsets in patients with severe influenza.@*Methods@#This was a single-center cross-sectional study in influenza patients admitted to Peking Union Medical College Hospital from August 2017 to April 2018. Peripheral blood lymphocyte subsets were detected by flow cytometry in both patients and 108 healthy controls. Influenza patients were divided into mild group and severe group. Severe patients were further classified into alive and fatal subgroups.@*Results@#A total of 42 influenza patients were recruited in this study, including 24 severe cases (6 deaths). The remaining 18 cases were mild. The peripheral blood lymphocyte counts and lymphocyte subset counts (B, NK, CD4+T, CD8+T) in either mild patients[795 (571,1 007), 43 (23,144), 70 (47,135), 330 (256,457), 226 (148,366) cells/μl respectively] or severe patients[661 (474,1 151),92 (52,139), 54 (34,134), 373 (235,555), 180 (105,310) cells/μl respectively] were both significantly lower than those of healthy controls [1 963 (1 603,2 394),179 (119,239), 356 (231,496), 663 (531,824), 481 (341,693) cells/μl respectively]. Meanwhile, the T cells and CD8+T counts in fatal patients [370 (260,537) cells/μl and 87 (74,105) cells/μl] were significantly lower than those in severe and alive patients [722 (390,990) cells/μl and 222 (154,404) cells/μl]. CD8+HLA-DR/CD8+and CD8+CD38+/CD8+T cell activating subgroups in mild cases[(53.7±19.2)% and 74.8% (64.1%,83.7%) respectively] were significantly higher than those in severe cases[(38.5±21.7)% and 53.3% (45.3%,67.2%) respectively].Moreover,CD8+HLA-DR/CD8+count in severe and alive group was higher than that in fatal group [(46.1±19.1)% vs. (18.2±14.6)%, P<0.01]. Logistic regression analysis showed that CD8+T cell count (OR=0.952, 95%CI 0.910-0.997, P=0.035) and CD8+HLA-DR/CD8+T (OR=0.916, 95%CI 0.850-0.987, P=0.022) were both negatively correlated with mortality.Peripheral blood lymphocyte counts in mild cases rapidly decreased within 1 day after diagnosis, and returned to the basic level one week later.@*Conclusions@#All peripheral blood lymphocyte subsets (T,B,NK) in patients with influenza are significantly reduced. These findings are consistent with the immunological characteristics of respiratory viral infections, in which peripheral lymphocytes (especially T cells) migrate to respiratory tract in the early stage and circulate to the peripheral blood after recovery. The activated CD8+T cell counts in peripheral blood are negatively correlated with the severity of disease, which could be considered as a prognostic indicator of severe influenza.

Re-defining T-Cell Exhaustion: Subset, Function, and Regulation

Acute viral infection or vaccination generates highly functional memory CD8 T cells following the Ag resolution. In contrast, persistent antigenic stimulation in chronic viral infection and cancer leads to a state of T-cell dysfunction termed T-cell exhaustion. We and other have recently identified a novel subset of exhausted CD8 T cells that act as stem cells for maintaining virus-specific CD8 T cells in a mouse model of chronic lymphocytic choriomeningitis virus infection. This stem cell-like CD8 T-cell subset has been also observed in both mouse and human tumor models. Most importantly, in both chronic viral infection and tumor models, the proliferative burst of Ag-specific CD8 T cells driven by PD-1-directed immunotherapy comes exclusively from this stem cell-like CD8 T-cell subset. Therefore, a better understanding of the mechanisms how CD8 T-cell subsets are regulated during chronic viral infection and cancer is required to improve the current immunotherapies that restore the function of exhausted CD8 T cells. In this review, we discuss the differentiation of virus-specific CD8 T cells during chronic viral infection, the characteristics and function of CD8 T-cell subsets, and the therapeutic intervention of PD-1-directed immunotherapy in cancer.

A novel cyclic peptide targeting LAG-3 for cancer immunotherapy by activating antigen-specific CD8 T cell responses

PD-1 and CTLA-4 antibodies offer great hope for cancer immunotherapy. However, many patients are incapable of responding to PD-1 and CTLA-4 blockade and show low response rates due to insufficient immune activation. The combination of checkpoint blockers has been proposed to increase the response rates. Besides, antibody drugs have disadvantages such as inclined to cause immune-related adverse events and infiltration problems. In this study, we developed a cyclic peptide C25 by using Ph.D.-C7C phage display technology targeting LAG-3. As a result, C25 showed a relative high affinity with human LAG-3 protein and could effectively interfere the binding between LAG-3 and HLA-DR (MHC-II). Additionally, C25 could significantly stimulate CD8 T cell activation in human PBMCs. The results also demonstrated that C25 could inhibit tumor growth of CT26, B16 and B16-OVA bearing mice, and the infiltration of CD8 T cells was significantly increased while FOXP3 Tregs significantly decreased in the tumor site. Furthermore, the secretion of IFN- by CD8 T cells in spleen, draining lymph nodes and especially in the tumors was promoted. Simultaneously, we exploited T cells depletion models to study the anti-tumor mechanisms for C25 peptide, and the results combined with MTT assay confirmed that C25 exerted anti-tumor effects CD8 T cells but not direct killing. In conclusion, cyclic peptide C25 provides a rationale for targeting the immune checkpoint, by blockade of LAG-3/HLA-DR interaction in order to enhance anti-tumor immunity, and C25 may provide an alternative for cancer immunotherapy besides antibody drugs.

Distribution of CD103+CD8+T cell infiltration in colorectal cancer tissues and its clinical significance / 中国肿瘤生物治疗杂志

@#Objective: To investigate the degree and distribution of tissue-resident CD8+ T cell (CD103+CD8+T cells) infiltration in colorectal cancer (CRC) tissues, and to analyze its relationship to patients’clinicopathological features and prognosis. Methods: Tissue chips of 88 cases of colon cancer tissues (No.HColA180Su14) and 77 cases of rectal cancer tissues (No. HRec-Ade180Sur-03) were obtained from Shanghai Outdo Biotech Co.,Ltd. Immunofluorescence staining was performed to examine the infiltration pattern and degree of CD103+CD8+T cells in the collected CRC tissues and their para-cancerous tissues. Wilcoxon rank test was used to compare CD103+CD8+T cell infiltration degree in CRC tissues and the para-cancerous tissues. Chi-square test was used to analyze the relationship between CD103+CD8+T cell infiltration in CRC and patients’clinicopathological features. Kaplan-Meier survival analysis was conducted to explore the correlation between CD103+CD8+T cell infiltration and patients’prognosis. Cox model was applied to analyze the correlation between different clinical parameters and patients’prognosis. Results: CD103+CD8+T cell infiltration presented no signifi ·cant differences between CRC and para-cancer tissues (P>0.05). Patients with distant metastasis had significantly lower CD103+CD8+T cell infiltration rate than patients without distant metastasis (P<0.01). There was no significant correlation between the infiltration of CD103+CD8+T cells and other clinicopathological features (P>0.05). Kaplan-Meier survival analysis showed that the overall survival (OS) of patients with high CD103+CD8+T cell infiltration was significantly longer than that of the patients with low infiltration (54.42% vs 25.00%, P<0.05). Multivariate Cox model analysis indicated that pathological grade (P<0.01) and high CD103+CD8+T cell infiltration (P<0.05) were independent prognostic factors for CRC. Conclusion： ：CD103+CD8+T cell infiltration in CRC is associated with patients’prognosis, suggesting that CD103+CD8+T cell plays an important role in the initiation and development of CRC.

PD-1 antibody enhanced anti-tumor efficacy of oxaliplatin against colon cancer in vitro and in vivo / 中国肿瘤生物治疗杂志

@#Objective: To explore the anti-tumor effects of oxaliplatin (OXA) combined with PD-1 antibody on colon cancer. Methods: Flow cytometry was used to detect the expression of PD-L1 in colon cancer cell lines HCT-116 and HT-29. Co-culture method was used to detect the secretion of cytokines and the changes of CD4/CD8 subsets in T-cells that co-cultured with HCT-116 cells, which were pretreated with OXAin combination with/without PD-1 antibody; The CT26 transplanted tumor model of colon cancer in BALB/c mice was established and treated with the combination of OXA and PD-1 to evaluate their anti-tumor efficacy. Meanwhile, CD8 antibody was used to scavenge CD8+ T cells in mice, and to evaluate the role of CD8+ T cells in the anti-tumor effect of OXA in vivo. Results: OXAcould significantly increase the expression of PD-L1 on the surface of colon cancer cells. Compared with pure T-cells, the T cells co-cultured with colon cancer HCT-116 cells that pre-treated by OXA, exhibited significantly reduced IL-2, IFN-γ and TNF levels (all P<0.05) in its culture supernatant and decreased ratio of CD4+memory T cell / CD8+TEMER (P<0.05), whereas there was increased cell proportion of the CD4+ (P>0.05) and CD8+ (P<0.05) naïve T cells. After co-treated with PD-1 antibody, compared with the single treatment of OXA, IFN-γ and IL-10 content (P<0.05) in culture supernatant and the subsets of CD8+ TCM and TEMRA ratio (P>0.05) were increased. In vivo experiments showed that OXAcombined with PD-1 antibody could enhance its anti-tumor activity, the tumor suppression rates were 25.6% (OXA) and 29.1% (αPD-1), respectively, however, the rate of tumor inhibition was increased to 58.2% when combined (P<0.05, compared to OXA or αPD-1 group). After scavenging CD8+T cells in mice, the antitumor activity of OXA dropped from 68.4% to 46.2% (P<0.05). Conclusion: OXA combined with PD-1 antibody had synergistic anti-tumor effect, and CD8+ T cells played an important role in the antitumor activity of OXA.

Carnosic acid enhances the anti-lung cancer effect of cisplatin by inhibiting myeloid-derived suppressor cells / 中国天然药物

Cisplatin and other platinum-based drugs are used frequently for treatment of lung cancer. However, their clinical performance are usually limited by drug resistance or toxic effects. Carnosic acid, a polyphenolic diterpene isolated from Rosemary (Rosemarinus officinalis), has been reported to have several pharmacological and biological activities. In the present study, the combination effect of cisplatin plus carnosic acid on mouse LLC (Lewis lung cancer) xenografts and possible underlying mechanism of action were examined. LLC-bearing mice were treated with intraperitoneal injection with cisplatin, oral gavage with carnosic acid, or combination with cisplatin and carnosic acid, respectively. Combination of carnosic acid and cisplatin yielded significantly better anti-growth and pro-apoptotic effects on LLC xenografts than drugs alone. Mechanistic study showed that carnosic acid treatment boosted the function of CD8 T cells as evidenced by higher IFN-γ secretion and higher expression of FasL, perforin as well as granzyme B. In the meantime, the proportion of MDSC (myeloid-derived suppressor cells) in tumor tissues were reduced by carnosic acid treatment and the mRNA levels of iNOS2, Arg-1, and MMP9, which are the functional markers for MDSC, were reduced. In conclusion, our study proved that the functional suppression of MDSC by carnosic acid promoted the lethality of CD8 T cells, which contributed to the enhancement of anti-lung cancer effect of cisplatin.

Sulforaphone enhances differentiation of memory precursor CD8+ cells by mTOR/ p-S6 signaling pathway / 中国肿瘤生物治疗杂志

@#Objective: To investigate the effect of sulforaphane (SFN) on CD8+ T cells differentiation, phenotype and the secretion of intracellular cytokines, as well as to study the underlying molecular mechanism. Methods: In the in vitro culture experiment, the cells were categorized into control group, SNF 10 mmol/L group and SNF 20 mmol/L group according to the SNF concentration. The effect of SFN treatment on CD8+ T cells differentiation, phenotype and cytokine secretion were detected by flow cytometry, and the effect of mTOR siRNA on the expression of CD127 and LKRG1 in CD8+T cells was also detected by flow cytometry. Expression of Bcl-2 and Bcl-6 were analyzed by qRT-PCR. The effect of SFN on apoptosis of CD8+T cells was examined byAnnexin-V/PI staining. The protein expressions of p-mTOR, p-S6 and b-actin were detected by western blotting. Results: SFN significantly promoted the formation of memory precursor CD8+ T cells and decreased the expression level of PD-1 and Tim-3 in CD8+T cells(P<0.01); meanwhile, after the treatment of SFN, the expressions of anti-apoptosis genes Bcl-2 and Bcl-6 were significantly increased while the apoptosis of CD8+ T cells was significantly inhibited and the protein expressions of p-mTOR and p-S6 were also significantly inhibited(P<0.05 or P<0.01). Moreover, mTOR siRNA could significantly increasethe expression of CD127 and decrease the expression of LKRG1 (all P<0.01). Conclusion: Sulforaphone promotes the formation of memory precursor CD8+T cells possibly by inhibiting the p-mTOR signaling pathway, and this could obtain more T cells to provide new thoughts for clinical immunotherapy.

Carnosic acid enhances the anti-lung cancer effect of cisplatin by inhibiting myeloid-derived suppressor cells / 中国天然药物

Cisplatin and other platinum-based drugs are used frequently for treatment of lung cancer. However, their clinical performance are usually limited by drug resistance or toxic effects. Carnosic acid, a polyphenolic diterpene isolated from Rosemary (Rosemarinus officinalis), has been reported to have several pharmacological and biological activities. In the present study, the combination effect of cisplatin plus carnosic acid on mouse LLC (Lewis lung cancer) xenografts and possible underlying mechanism of action were examined. LLC-bearing mice were treated with intraperitoneal injection with cisplatin, oral gavage with carnosic acid, or combination with cisplatin and carnosic acid, respectively. Combination of carnosic acid and cisplatin yielded significantly better anti-growth and pro-apoptotic effects on LLC xenografts than drugs alone. Mechanistic study showed that carnosic acid treatment boosted the function of CD8 T cells as evidenced by higher IFN-γ secretion and higher expression of FasL, perforin as well as granzyme B. In the meantime, the proportion of MDSC (myeloid-derived suppressor cells) in tumor tissues were reduced by carnosic acid treatment and the mRNA levels of iNOS2, Arg-1, and MMP9, which are the functional markers for MDSC, were reduced. In conclusion, our study proved that the functional suppression of MDSC by carnosic acid promoted the lethality of CD8 T cells, which contributed to the enhancement of anti-lung cancer effect of cisplatin.

Expression and significance of T cell immunoreceptor with Ig and immunoreceptor tyrosine-based inhibitory domains (TIGIT) on peripheral CD4+ T and CD8+ T cells from patients with rheumatoid arthritis / 中华微生物学和免疫学杂志

Objective To investigate the expression of T cell immunoreceptor with Ig and immunoreceptor tyrosine-based inhibitory domains (TIGIT) on peripheral CD4+ T and CD8+ T cells from patients with rheumatoid arthritis (RA) and its significance in order to clarify its role in the development of RA.Methods Peripheral blood samples were collected from 81 patients with RA and 33 healthy controls (HC).Expression of TIGIT on the surface of peripheral blood leukocytes was detected by flow cytometry.Differences in TIGIT expression between RA and HC groups were comparatively analyzed.Correlations of TIGIT expression on CD4+ T and CD8+ T cells with several laboratory indexes were analyzed.All data were statistically analyzed.Results (1) The percentage of TIGIT-expressing CD3+ T cells in patients with RA was significantly higher than that in HC (P<0.01).Moreover, the median fluorescence intensity (MFI) of TIGIT on CD3+ T cells was significantly elevated in patients with RA as compared with that in HC (P<0.01).No significant difference in the expression of TIGIT on B cells, monocytes or neutrophils was observed between RA and HC groups.(2) The percentages of TIGIT-expressing CD4+ T and CD8+ T cells were significantly elevated in patients with RA as compared with those in HC (P<0.01).Moreover, the MFI of TIGIT on CD4+ T and CD8+ T cells were significantly elevated in patients with RA as compared with those in HC (P<0.01).(3) The percentages of both TIGIT-expressing CD4+ T cells and TIGIT-expressing CD8+ T cells in patients with RA were positively correlated with erythrocyte sedimentation rate (ESR) (rs=0.355, P<0.01;rs=0.277, P=0.013).(4) The percentages of both TIGIT-expressing CD4+ T cells and TIGIT-expressing CD8+ T cells in patients with RA were positively correlated with rheumatoid factor (RF) (rs=0.265, P=0.017;rs=0.366, P<0.01).The MFI of TIGIT on CD4+ T cells was positively correlated with RF in RA group (rs=0.226, P=0.043).The percentage of TIGIT-expressing CD4+ T cells was positively correlated with anti-cyclic citrullinated peptide (anti-CCP) antibody in patients with RA who were positive for anti-CCP antibody (rs=0.324, P=0.012).(5) The percentage of TIGIT-expressing CD4+ T cells as well as the MFI of TIGIT on CD4+ T cells in patients with RA was positively correlated with Disease Activity Score-28 (DAS28) (r=0.232, P=0.038;r=0.343, P<0.010).Conclusion The expression of TIGIT on T cells is elevated in patients with RA and correlated with inflammatory markers, antibody production and disease activity.

Activation of CD8+T cells regulated by γ-aminobutyric acid and its receptors / 器官移植

Objective To evaluate the effect of γ-aminobutyric acid (GABA) and its receptors upon the proliferation of CD8+T cells.Methods The splenic CD8+T cells of Balb/c mice were obtained by CD8+f cell magnetic bead sorting kit.Under the effect of CD3/CD28-activated magnetic bead,CD8+T cells were stimulated by different concentrations of GABA.5-bromo-2-deoxyuridine (BrdU) labeling and flow cytometry were performed to detect the proliferation of CD8+T cells.The expression levels of GABA-A and GABA-B receptor before and after CD8+T cell activation were compared by fluorescent quantitative real-time polymerase chain reaction (PCR).Result Flow cytometry result revealed that GABA could inhibit the proliferation of activated CD8+T cells,manifested as significant decrease in the quantity of CD152+CD8+T cells.Fluorescent quantitative real-time PCR demonstrated that GABA-A receptor subtypes α2,α6 and GABA-B receptor subtype 1a were expressed only when the CD8+T cells were activated.After CD8+T cell activation,the quantity of GABA-A receptor subtypes α3,αs,β2,β3,γ1,γ2 and θ were significantly increased,whereas the quantity of GABA-B2R and GABA-B1b did not significantly differ before and after CD8+T cell activation.Conclusions GABA can suppress the proliferation of activated CD8+T cells.The activation of CD8+T cells is regulated by GABA receptors.However,the underlying mechanism remains to be elucidated.

Effect of permissive hypercapnia on CD4 + and CD8 + T cells of rats with acute rejection after lung ;transplantation / 器官移植

Objective To investigate the effect of permissive hypercapnia on CD4 +and CD8 +T cells of rats with acute rejection after lung transplantation. Methods Twenty-four male Wistar rats and 12 male SD rats were paired and randomly divided into 3 groups (6 pairs per group). SD and Wistar rats were used as the donors and recipients in the control group and treatment group,respectively,and Wistar rats were used as the donors and recipients in the allograft group. Acute rejection rat model of orthotopic left lung transplantation was established by Cuff method. The treatment group was treated with 50% oxygen and 8% carbon dioxide after reperfusion,but only 50% oxygen for the control group and allograft group after reperfusion. Expressions of CD4 +and CD8 +T cells in transplanted lung tissue were detected with immunohistochemical (IHC)method on 7 d after the operation. Proportion of CD4 +and CD8 +T cells in peripheral blood was detected with flow cytometry. Furthermore,levels of interleukin (IL)-2 and interferon (IFN)-γin peripheral blood were detected with enzyme-linked immune absorbent assay (ELISA). Results The IHC results showed that,compared with the control group,the expression of CD8 +T cells in transplant lung tissue of rats decreased significantly in both the treatment group and allograft group. The results of flow cytometry showed that compared with the control group,the proportion of CD8 +T cells decreased significantly in both treatment group and allograft group (both P<0.05 ). ELISA results showed that,compared with the control group,levels of IL-2 and IFN-γdecreased significantly in both treatment group and allograft group (both P<0.05 ). Conclusions Permissive hypercapnia can inhibit the acute rejection after lung transplantation through inhibiting the proliferation of CD8 +T cells and release of inflammatory cytokines in CD4 +T cells.

Study on the phenotype and function of CD8+Treg cells induced by ovarian cancer cell / 实用医学杂志

Objective To investigate the phenotype and function of CD8+T cells cultured with SK-OV-3. Methods Transwell coculture experiments were conducted in 24-well plates with inner wells to separate CD8+ T cells and SK-OV-3. After 5 days of culture, CD8+ T cells were washed, and 1 × 106 cells were collected for Foxp3, CD25, CD28, CTLA-4 and GITR mRNA analysis and 2 × 106 cells were collected to detect expression of Foxp3, CD25, CD28, CTLA-4 and GITR in CD8+ T cells by flow cytometry. CD8+T cells that cultured alone or with SK-OV-3 were added at ratios of 1∶0 , 1∶1 , 1∶5 , 1∶10 , and 0∶1 to na?ve CD4+ T cells in 96-well plates. All wells were cultured with the presence of irradiated PBMCs and anti-CD3 antibody. After 72 h, [3H]-thymidine was added for 16 h prior to the determination of proliferation by scintillation counting. Results Compared with CD8+ T cells cultured without SK-OV-3 , the expression of Foxp3 and CTLA-4 was increased and CD28 expression was decreased in CD8+ T cells cultured with SK-OV-3 (both P < 0.001). We found that CD8+T cells cultured with SK-OV-3 significantly suppressed the na?ve CD4+ T cell proliferation induced by the anti-CD3 stimulation in a dose-dependent manner. In contrast, CD8+ T cells cultured without SK-OV-3 did not suppress na?ve CD4+ T cell proliferation. Conclusion Ovarian cancer cell can induce the suppressive CD8+Treg, which is an important link of the immunosuppressive microenvironment in ovarian cancer.

Changes of myeloid derived suppressor cells and T cells in lung cancer mice / 中国免疫学杂志

Objective:To investigate the changes of CD4+T cells,CD8+T cells and myeloid derived suppressor cells( MDSC) in immune organs of lung cancer mice.Methods: Lung cancer mouse models were made by subcutaneously injection of Lewis lung cancer cell line( LLC).The CD4+T cell,CD8+T cell and MDSC were detected by flow cytometry.Results:Compared to that of normal control mice,the ratio and numbers of CD4+and CD8+T cell were significantly decreased in the spleen and lymph nodes of lung cancer mice.The number of CD4+T cells had no significant change while CD8+T cells decreased in the bone marrow of lung cancer mice.However,the ratio and number of MDSC were significantly increased in the bone marrow,spleen and lymph nodes of lung cancer mice compared to that of normal control mice.Conclusion: The development of lung cancer leads to decreased T cells and increased MDSC;which may induce immune tolerance to tumor cells.

Attenuation of Peripheral Regulatory T-Cell Suppression of Skin-Homing CD8+T Cells in Atopic Dermatitis

PURPOSE: Cutaneous lymphocyte-associated antigen (CLA)-expressing CD8+T cells have been known to play an important role in the pathogenesis of atopic dermatitis (AD). However, the mechanisms underlying the loss of self-tolerance remain unclear. Regulatory T cells (Tregs) play a key role in the development of homeostasis in the immune system. We, therefore, hypothesized that a reduced ability of Tregs to inhibit autologous CD8+CLA+T cells might be underlying mechanism in AD. MATERIALS AND METHODS: CD8+CLA+T cells and Tregs were obtained from the peripheral blood of AD patients and control volunteers. The frequencies of CD8+CLA+T cells were evaluated. The proliferative responses of CD8+CLA+T cells were assessed by flow cytometry, and the levels of transforming growth factor-beta1 (TGF-beta1) and interleukin-10 (IL-10) in culture supernatants were detected by enzyme-linked immunosorbent assay. RESULTS: Our results revealed higher frequency and increased expression of perforin and granzyme-B in peripheral CD8+CLA+T cells in AD, and lower inhibitory ability of Tregs on proliferation of CD8+CLA+T cells in AD. Meanwhile, the levels of TGF-beta1 produced by Tregs were significantly lower in AD, and anti-TGF-beta1 abolished such suppression. CONCLUSION: The attenuated inhibitory ability of Tregs on hyper-activated autologous CD8+CLA+T cells, mediated by TGF-beta1, plays an important role in the pathogenesis of AD.

Study of the immunogenicity and virulence of replication-competent recombinant vaccinia virus in CD4+T cell-depleted mice / 中华微生物学和免疫学杂志

Objective To investigate the effects of CD4+T cell depletion in BALB/c mice on the immunogenicity and virulence of replication-competent recombinant vaccinia virus. Methods Twelve BALB/c mice were inoculated with recombinant Tiantan vaccinia ( rTV, n=8 ) or vaccinia virus Tiantan strain ( VTT, n=4) by tail scarification after the depletion of CD4+T cells with anti-CD4 monoclonal anti-body( McAb) injected intraperitoneally for three days before virus inoculation.A control group without anti-body treatment was set up accordingly.Several parameters including the body weight, pocks on tail, viral shedding and the percentage of CD4+T cells were monitored.In the fourth week after virus infection, ovaries were collected from mice and viral loads in the tissue were titrated by plaque forming assay on chick embryo fibroblast ( CEF) cells.The specific cellular immune responses against vaccinia virus and HIV induced by inoculation of VTT and rTV respectively were detected by intracellular cytokine staining ( ICS) assay.ELISA was used to detect antibodies against vaccinia virus and HIV-1 gp120.Results All mice with or without CD4 McAb treatment showed typical poxvirus pocks on tails after inoculation of vaccinia viruses, but none of them developed secondary or satellite lesions.It took a longer time for CD4+T cell-depleted mice to heal from lesions, to regain body weights and to release viruses than the mice in control group.No vaccinia virus was detected in the ovaries of CD4+T cell-depleted mice or mice in control group.The mean absorbance( A) values for the detection of HIV-specific and vaccinia virus-specific antibodies in CD4+T cell-depleted mice with ELISA were respectively 0.119 and 0.168, which were significantly lower than those in mice of control group.The titers of neutralizing antibodies against vaccinia virus in McAb/rTV treated mice (1 ∶321) were lower than those in rTV treated mice (1 ∶1286) (P<0.05).The percentages of CD4+T cells secreting IFN-γ(0.654%) in McAb/rTV treated mice were significantly lower than those in rTV treated mice in the fourth week after immunization (P <0.0004).No significant differences with the vaccinia virus-specificCD8+ T cell responses were observed among mice with or without CD4+T cells depletion.Conclusion Thereplication and dissemination of replication-competent recombinant vaccinia virus could be effectively controlledin the mice with CD4+ T cell-depletion.The depletion of CD4+ T cells significantly reduced the humoraland CD4+ T cell responses, but had no effect on CD8+ T cell responses.

Effect of halometasone in combination with scutellaria baicalensis georgi on the vitiligo mice / 中国药理学通报

Aim To study the effect of halometasone in combination with scutellaria baicalensis georgi on the vitiligo mice induced by monobenzone. Methods 40% monobenzone cream was applied to induce vitiligo in C57BL/6 mice. Through the halometasone, halo-metasone and scutellaria baicalensis georgi combined with 40% monobenzone cream, the influence of halo-metasone and scutellaria baicalensis georgi on mice de-colorizing was studied. Hair decolorizing was observed with the naked eye, the skin decolorizing was observed by reflectance confocal microscopy ( RCM ) , and CD8 +T cell infiltration was tested with immunofluores-cence detection. The serum levels of interleukin-6(IL-6 ) and tumor necrosis factor-α( TNF-α) were deter-mined by enzyme linked immunosorbent assay ( ELISA) . Results Mice in model group showed de-pigmentation at both the monobenzone application part and non-application part. The halometasone group did not show significant therapeutic efficacy. In halometa-sone and scutellaria baicalensis georgi treatment group, there was less decolorization, the occurrence ratio, the scores of occurring time and size were lower compared with model group. There were fewer infiltrated lympho-cytes and CD8 +T cells. Halometasone and scutellaria baicalensis georgi group also showed that the serum levels of IL-6,TNF-α decreased. Conclusion Halo-metasone and scutellaria baicalensis georgi have thera-peutic effect on vitiligo mice induced by monobenzone.