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@#Human leukocyte antigen-E (HLA-E) is highly expressed in many kinds of cancer and associated with the prognosis of patients in a cancer-type-dependent manner. HLA-E plays an important anti-tumor immunomodulatory role mainly by binding to activating receptor (NKG2C) or inhibitory receptor (NKG2A) on NK cells or T cells. Based on this, targeting HLA-E/NKG2A to block the interaction of HLA-E with NKG2A or inhibit HLA-E expression may be one of the promising strategies for augmenting anti-tumor immune response. Based on the functional features of HLA-E, developing enhanced or universal engineered-T/NK cells adoptive cellular immunotherapies has the potential of enhancing the therapeutic effects of adoptive cellular immunotherapies, with good prospects in research and clinical application. How to effectively combine the strategy of targeting HLA-E/NKG2A with other immune therapies for more precise immunotherapy and better clinical therapeutic effects remains one of the challenges in the research and application of anti-tumor immuotherapies.
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ObjectiveTo explore the mechanism of Si Junzitang in regulating the expression of NKG2A to affect the anti-colon cancer function of natural killer （NK） cells. MethodNK cells isolated from healthy honors were cultured and used to construct the three incubation models of NK cells， human colon cancer HCT116 cells， and NK cells + HCT116 cells （co-incubation）. real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was conducted to determine the mRNA levels of natural killer group 2 member A （NKG2A） and interleukin （IL）-15 in NK cells， as well as the mRNA level of histocompatibility leucocyte antigen E （HLA-E） in HCT116 cells. The secretion of IL-15 was detected by enzyme-linked immunosorbent assay （ELISA）. Methyl thiazolyl tetrazolium （MTT） assay was employed to determine the applicable concentration of IL-15 and test the effects of Si Junzitang and IL-15 on the activities of NK cells and the HCT116 cells in the co-incubation model. The effects of Si Junzitang and IL-15 on the mRNA levels of NKG2A in NK cells and HLA-E in HCT116 cells were detected by Real-time PCR. Monalizumab （M， anti-NKG2A mab） was used to block the NKG2A-HLA-E pathway in co-incubation model， and then the proliferation of HCT116 cells was detected by MTT assay. ResultThe interaction of NK cells and HCT116 cells up-regulated the mRNA levels of NKG2A in NK cells and HLA-E in HCT116 cells （P<0.05）， as well as the expression level and secretion of IL-15 （P<0.05）. Compared with the blank group， Si Junzitang and Si Junzitang + IL-15 promoted the proliferation and improved the anti-colon cancer function of NK cells （P<0.01）. Furthermore， they down-regulated the mRNA levels of NKG2A in NK cells and HLA-E in the HCT116 cells co-incubated with NK cells （P<0.01）. M and IL-15 + M inhibited the proliferation of HCT116 cells compared with the groups without M （P<0.01）. ConclusionThe interaction of NK cells and HCT116 cells can induce activation of NKG2A-HLA-E pathway to impair NK cell function. Si Junzitang can inhibit the activation of NKG2A-HLA-E pathway to restore the anti-colon cancer function of NK cells.
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Objective:To study the changes of NKG2C/NKG2A expressed on T cells in HIV chronically infected individuals and HAART-treatment AIDS patients and the relationship with disease progression of HIV. Methods: We collected peripheral blood from HIV chronically infected individuals,HAART-treatment AIDS patients and healthy human and used the flow cytometry by staining fluorescent antibody to detect the NKG2C/NKG2A receptors expressed on T cells. Results:NKG2C+,NKG2A+ and NKG2C+NKG2A-expressed on T cells in HIV chronically infected individuals were significantly higher than the healthy control group ( P=0. 025,P=0. 032,P=0. 029),while in HAART-treatment AIDS patients were significantly lower than that in HIV chronically infected individuals (P=0. 033,P=0. 037,P=0. 018),returned to the normal levels with no significant difference compared with the healthy control group. The absolute number of peripheral blood CD4+ T lymphocytes in HIV chronically infected individuals was negative correlation with T cells which expressing NKG2A+,NKG2C+NKG2A+ and NKG2C-NKG2A+( r=-0. 697,P<0. 000 1;r=-0. 463,P=0. 015;r=-0. 693,P<0. 000 1). What was more,the absolute number of peripheral blood CD4+ T lymphocytes had positive correlation with the ratio of NKG2C and NKG2A expressed on T cells receptor in HIV chronically infected individuals(r=0. 476,P=0. 012). Conclusion:Studying the expression of NKG2C and NKG2A receptors on T cell has great significance in HIV infected individuals, which may provide a scientific basis for clinical prognosis of HIV infection.
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Accumulating evidence has shown that allogeneic blood transfusions can induce significant immunosuppression in recipients, and thereby increase the risk of postoperative infection and/or tumor relapse. Although it is well known that natural killer (NK) cells are responsible for the immunodepression effects of transfusion, the underlying mechanisms remain obscure. In this study, we investigated the role of NK cells in transfusion-induced immunodepression in β-thalassemia major. The proportion of circulating NK cells and the expression of NK receptors (NKG2A, CD158a, NKP30, NKP46 and NKG2D) as well as CD107a were detected by multicolor flow cytometry. IFN-γ production by circulating NK cells was detected by intracellular cytokine staining. Our results showed that the proportion and cytotoxicity (CD107a expression) of circulating NK cells in transfusion-dependent β-thalassemia major patients were remarkably lower than those of β-thalassemia minor patients or healthy volunteers. Expression of NKG2A inhibitory receptor on circulating NK cells in patients with β-thalassemia major was remarkably up-regulated, but there were no significant differences in the expression levels of NKP30, NKP46, NKG2D, CD158a and IFN-γ. These results indicate NKG2A inhibitory receptor may play a key role in transfusion-induced immunodepression of NK cells in patients with β-thalassemia major.
Subject(s)
Adolescent , Child , Female , Humans , Male , Flow Cytometry , Gene Expression Regulation , Immunosuppression Therapy , Killer Cells, Natural , Allergy and Immunology , Metabolism , NK Cell Lectin-Like Receptor Subfamily C , Blood , Allergy and Immunology , NK Cell Lectin-Like Receptor Subfamily K , Blood , Allergy and Immunology , Natural Cytotoxicity Triggering Receptor 1 , Blood , Allergy and Immunology , Natural Cytotoxicity Triggering Receptor 3 , Blood , Allergy and Immunology , Receptors, KIR2DL1 , Blood , Allergy and Immunology , Transfusion Reaction , beta-Thalassemia , Blood , Allergy and Immunology , PathologyABSTRACT
Objective:To investigate the correlation between NKG2A+NK cells and regulatory T cells in peripheral blood of patients with chronic hepatitis B virus infection, and explore the clinical significances.Methods: Forty-six patients with chronic hepatitis B virus infection and 17 health individuals were included in this study.HBV DNA levels were measured by Real-time quantitative PCR ( FQ-PCR) .NKG2A+NK cells and Treg in PBMC were quantitatively analyzed by flow cytometry.Results:According to HBV DNA levels,the CHB patients were divided into two groups:Low HBV DNA group(Low viral load group,300-104 U/ml)and High HBV DNA group( High viral load group,105-108 U/ml).We found that ALT levels of High HBV DNA group were obviously higher than Low HBV DNA group(P<0.05).The frequenies of CD56dim NK cells of High HBV DNA group were obviously higher than low HBV DNA group ( P<0.05 ), and similarly the percentages of NKG2A+CD56dim NK cells of High HBV DNA group were significantly higher than Low HBV DNA and control groups ( P<0.05).We also found that the percentages of regulatory T cells ( Treg) of High HBV DNA group were significantly higher than Low HBV DNA and control groups ( P<0.05).In addition,the proportions of NKG2A+CD56dim NK cells were positively correlated with High HBV DNA levels (r=0.59,P<0.05) and the percentages of Treg(r=0.53,P<0.05) in CHB patients.Conclusion:NKG2A+CD56dim NK cells may closely relate to the HBV-related immune escape and the progress of CHB.
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Objective To assess the efficacy of combination of Jiehe pellet and the standardized anti-tuberculosis therapeutic regimen for pulmonary tuberculosis complicating cervical lymph node tuberculosis in the aged. Methods A total of 103 aged patients with pulmonary tuberculosis complicating cervical lymph node tuberculosis were enrolled and randomly allocated to either a standardized anti-tuberculosis therapeutic regimen group (control group with 51 patients) or a standardized anti-tuberculosis therapeutic regimen plus Jiehe pellet group (treatment group with 52 patients). The patients in the control group and the treatment group received the treatment with 2HRZE/4HR and 2HRZE/4HR plus Jiehe pellet for 6 months, respectively. The abscessed lymph nodes were treated by either total excision or incision and drainage after 4 weeks of medicine treatment in both groups. Sputum smear was examined for acid-fast bacilli. The CD8 cells expressing natural killer T cells receptors NKG2A, NKG2D in peripheral blood were detected by flow cytometry. The treatment outcome was measured at the end of treatment. Results The rates of lesion resolution (78.85%vs. 58.82%;χ2=4.439, P<0.05) and cavity closure (62.86% vs. 35.48%;χ2=3.893, P<0.05) in the treatment group were significantly higher than those in the control group. In the end of 2, 4 and 6 months of treatment, cumulative rates of sputum conversion from positive to negative in the treatment group were significantly higher than those in the control group (χ2 were 5.343, 5.067 and 4.118,all P<0.05). The CD8 cells expressing NKG2A after treatment in the treatment group were significantly lower than those before treatment in the treatment group (t=9.510, P<0.01) and after treatment in the control group (t=9.832, P<0.01);the CD8 cells expressing NKG2D after treatment in the treatment group were significantly higher than those before treatment in the treatment group (t=10.622, P<0.01) and after treatment in the control group (t=10.433, P<0.01). The serum levels of IL-6 and TNF-αafter treatment were significantly lower than those before treatment in both groups (t were 17.344 and 21.142 in the treatment group, 10.984 and 12.203 in the control group;all P<0.01 );the serum levels of IL-6 and TNF-α after treatment in the treatment group were significantly lower than those after treatment in the control group (t were 7.832 and 5.478,all P<0.01). The serum IL-10 levels after treatment were significantly higher than those before treatment in both groups (t were 12.454 in the treatment group, 7.934 in the control group; all P<0.01 ); and the serum IL-10 level after treatment in the treatment group was significantly higher than that after treatment in the control group (t=4.720, P<0.01). The effective rate for cervical lymph node tuberculosis in the treatment was significantly higher than that in the control group (88.5%vs. 64.7%;χ2=6.855, P<0.01). Conclusion Combination of Jiehe pellet and the standardized anti-tuberculosis therapeutic regimen may improve immune function, increase the rate of sputum conversion from positive to negative, and facilitate lesion resolution in aged patients with pulmonary tuberculosis complicating cervical lymph node tuberculosis.
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Human cytomegalovirus(HCMV)infection is quite prevalent in population. HCMV triggers important disorders in pregnant women,immune-compromised individuals and organ-transplant patients. For dec-ades,more and more scholars believe that NK cells are important immune cells against HCMV. The activity of NK cells largely depends on the balance between the signals transducted by inhibitory receptors and activatory re-ceptors,therefore the study of NK receptors is of great importance. It may be helpful to the basic research and clinical treatment of HCMV infection. Here,this paper reviews the changes and the molecular mechanism of NK receptors in the control of HCMV infection.
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Objective The aim of this study is to investigate CD+8 natural killer T cell receptors NKG2D and NKG2A expression in peripheral blood of patients with lung cancer and discuss the relation between imbalance expression of NKG2A and NKG2D and tumor immune escape. Methods Flow cytometry was used to determine the percentage of NKG2D and NKG2A-expressing of CD+8 NKT cells in peripheral blood of 95 untreated lung cancer patients and 50 healthy controls. Results NKG2D was lower expressed on CD+8 NKT in lung cancer, the level of NKG2D in patients (77.07±5.77) % was significantly lower than that in the controls (84.13±4.49) % (t =8.14, P <0.05). In the TNM stage, the level of NKG2D in patients of Ⅰ-ⅢA, ⅢB, Ⅳ stage were (81.07±5.02) %, (76.95 ±4.70)%, (72.80±5.16) %, respectively, the level of NKG2D was significantly decreased in order (F =18.74, P <0.05). NKG2A was expressed higher on CD+8 NKT in lung cancer, the level of NKG2A in patients (33.58±8.82) % was significantly higher than that in the controls (25.31 ±8.38) % (t =-5.46, P<0.05). In the TNM stage, the level of NKG2A in patients of Ⅰ - Ⅲ A, ⅢB, Ⅳ stage were (25.10±6.93) %, (33.24±3.76) %, (43.64±6.10) %, respectively, the level of NKG2A was significantly increased in order (F =75.73,P <0.05). Conclusion Imbalance expression of NKG2A and NKG2D may restrain the function of CD+8 NKT cell of lung cancer patients in peripheral blood and that may be one of important factors in tumor immunological escape.
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Objective NKT cells are very important as a kind of non-specific immune cells. Much attention in antitumor significance has been received in the study of its effect on malignant diseases. The aim of this study was to detect the expression of NKT cells and its CD+8 NKT subsets in peripheral blood of esophageal patients and normal person, and to analyze the changes in the expression of NKG2D and NKG2A receptorsand its clinical pathological factors. Methods By flow cytometric analysis, 53 patients with esophageal carcinoma and 39 normal controls were analysed for peripheral blood of NKT cells and CD+8 NKT subsets, and the expression of NKT cells NKG2A and expression of NKG2D receptor. The clinical pathological factors were collected for the comparative analysis. Results Compared with the normal control group, the expression of NKT cells in peripheral blood of esophageal patients increased [(4.32±0.73) %, (5.97±1.29) %] (t =3.562, P <0.01), and the expression level of its surface receptor NKG2D reduced [(17.56±5.92) %, (15.12±1.56) %] (t =3.892, P <0.05), but the express levels of NKG2A [(4.02±1.41) %, (5.99±4.59) %] in creased (r = 4.015, P <0.05), those expression change with the development of the esophageal cancer. Conclusion The increased expression of NKT cells and CD+8 NKT subsets in the peripheral blood of patients with esophageal carcinoma refletcs that the immune feedback of patients' antineoplastic effect is strengthened. The decresed expression of the active receptor NKG2D and the increased expression of the inhibitory receptor NKG2A on NKT cells might be one of mechanisms leading to the reduction of NKT cell activity and immune escape of patients with esophageal carcinoma. The changes of surface receptors of NKT cells may be associated with the development of the esophageal cancer.
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Objective:To investigate the expression and function of CD226 on NK s ubsets and its coexpression with other activation receptor and inhibition recept or on NK cells. Methods:The expression of CD226 on CD56 bright and CD56 dim NK subsets and coe xpress ion with CD16 and NKG2A in PBMC and MLC in the presence or absence of IL-2 or IL-15 were detected by double fluorescent staining and flow cytometry analysis. The level of IFN-? in the supernatants of PBMC culture and MLC treated with o r without IL-2 or IL-15 were evaluated by ELISA. 51Cr release assay w as employed to measure the specific lysis of NK cells killing target K562 cells. Results:CD226 was mainly expressed on CD56 dim NK subsets in PBMC. When s imulated by IL-2, CD226 expression was shifted to CD56 bright NK subsets, while IL-15 increased the subpopulation of NKG2A+CD226+double positive cell s. In MLC-generated NK cells, CD226 was mainly expressed on CD56 dim NK su bsets, and also shifted to CD56 bright NK subsets in the addition of IL-15 . Furt hermore, the percentage of CD16+CD226+和NKG2A+CD226+ subsets were increa sed when stimulated by IL-2 or IL-15. There was great increase in IFN-? lev el in the supernatants of PBMC culture in the presence of IL-2 or IL-15, but no difference in the supernatants of MLC treated with or without two cytokine s. Moreover, the cytotoxicity of NK cells in PBMC and MLC were greatly enhanced by IL-2 or IL-15. Conclusion:CD226 is mainly expressed on CD56 bright NK subsets in IL-2 or IL-1 5 activated NK cells, and is coexpressed with CD16 and NKG2A preferentiatly, whi ch maybe involve in the modulation of cytotoxicity of NK cells based on the balance of coexpressed activation and inhibition receptors. [