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21.
The objective of this article is to evaluate whether the tumoricidal activity of mouse IFN R−/− nature killer (NK) cells is induced by Newcastle disease virus hemagglutinin-neuraminidase (NDV-HN) stimulation, and to investigate what is the mechanism of the HN-stimulated NK cells to kill mouse hepatoma cell line in vitro. The mouse IFN R−/− NK cells were stimulated for 16 hr with 500 ng/mL NDV-HN in 1640 medium. Quantify the cytotoxic activities of NK cells against mouse hepatoma cells (Hepa1-6) by flow cytometry. Granzymes B (GrB) and Fas/FasL concentrations in the supernatants of IFN R−/− NK cells medium were determined by specific ELISA assay. The expression of cell surface GrB and Fas was determined by Western blot. NDV-HN stimulation enhanced tumoricidal activity of IFN R−/− NK cells toward Hepa1-6 in vitro. Treating with anti-HN neutralizing mAb induced significant decline in the cytotoxicity of IFN R−/− NK cells toward Hepa1-6 cell line (P < 0.05). After treating with anti-HN protein (1 μL/mL), Syk-specific inhibitor Herbimycin A(250 ng/mL) and NF-κB inhibitor PDTC (500 ng/mL) downregulated the tumoricidal activity of HN-stimulated IFN R−/− NK cells (P < 0.05). Moreover, significant suppressions in the production of GrB and Fas/FasL were observed in HN-stimulated IFN R−/− NK cells (P < 0.05). Thus, we concluded that killer activation receptors pathway is involved in the IFN-γ-independent GrB and Fas/FasL expression of NDV-HN-stimulated IFN R−/− NK cells, and these are activated by Syk and NF-κB. Anat Rec, 302:1718–1725, 2019. © 2019 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association for Anatomy  相似文献   
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Journal of Artificial Organs - This is a single-center retrospective study to summarize clinical outcomes of patients requiring surgical continuous-flow left ventricular assist device (HeartMate...  相似文献   
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We assessed the prevalence characteristics of single and multiple high-risk human papillomavirus (HR-HPV) infections. A total of 1783 women who underwent colposcopy and cervical biopsy for abnormal ThinPrep Cytology Test and/or HR-HPV subtype genotyping results were enrolled in the study. Among the participants, 770 were diagnosed with cervicitis, 395 with cervical intraepithelial neoplasia grade 1 (CIN1), 542 with CIN2-3, and 76 with squamous cell carcinoma (SCC), with HR-HPV infection rates of 75.8%, 85.8%, 95.9%, and 88.4%, respectively. The prevalence of total and multiple HR-HPV infections exhibited a bimodal age distribution with a peak at ≤25 years, a decline with age and a second peak at ≥55 years, whereas single HR-HPV infections exhibited one peak from 35 to 44 years. The four most dominant HPV genotypes were HPV 16 (29.5%), 52 (15.0%), 58 (14.2%), and 18 (10.4%). In total, 67.0%, 70.4%, and 82.1% of patients with CIN1, CIN2-3, and SCC, respectively, had a single HR-HPV infection, which increased significantly with the aggravation of the cervical lesion grade (P = 0.045). Patients with a single HPV 16 infection had higher incidences of CIN2+ (62.2%) than those with multiple HPV 16 infections (52.4%) (P = 0.021). Patients coinfected with HPV 16 had higher CIN2+ incidence than those with single HPV 52, 31, 33, 35, 39, 45, 51, 56, or 59 infections (P < 0.001). This study provided baseline data on the prevalence characteristics of single and multiple HR-HPV infections in women attending a gynecological outpatient clinic in Beijing.  相似文献   
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The Cluster of differentiation 226(CD226)/T cell immunoglobulin and immune receptor tyrosine-based inhibitory motif domain (TIGIT) axis plays an important role in the balance of the immune response. A previous study showed that CD226 is involved in CD4+ T cell differentiation and that blocking CD226 may attenuate experimental autoimmune encephalomyelitis (EAE) development. However, the molecular mechanisms underlying this process remain incompletely understood. In this study, it was found that Cd226−/− mice were less susceptible to EAE and that there was less T helper 17(Th17) cell infiltration with higher levels of regulatory cells (Tregs) infiltration in the Cd226−/− EAE mouse central nervous system (CNS) compared with that in the WT EAE mouse CNS. Moreover, the suppressive function of Cd226−/− Tregs was upregulated compared with that of WT Tregs. Furthermore, it was observed that the expression levels of CTLA-4 and TIGIT on Cd226−/− Tregs were higher than those on WT Tregs during EAE in the spleen and CNS. Our results demonstrate a pivotal role for CD226 in attenuating Treg function in EAE that was associated with downregulating the expression levels of CTLA-4 and TIGIT.  相似文献   
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Song  In Hye  Kim  Young-Ae  Lee  Hyeonjin  Park  Hye Seon  Park  In Ah  Sim  Chan Kyu  Lee  Myeong Sup  Gong  Gyungyub  Lee  Hee Jin 《Immunologic research》2019,67(6):469-477
Immunologic Research - The expression of major histocompatibility complex class I (MHC I) in tumor cells is regulated by interferon signaling, and it is an important factor in the efficacy of...  相似文献   
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Song  Hongsheng  Liu  Anzhou  Liu  Guoxing  Wu  Fang  Li  Zhitao 《Immunologic research》2019,67(4-5):416-423

T follicular regulatory (Tfr) cell is a recently discovered subset of T regulatory (Treg) cells. The main function of Tfr cells is thought to suppress germinal cancer reaction and inhibit B cell proliferation and Ig production. However, recent studies demonstrate that Tfr cells may be required for high-affinity Ig formation during acute virus infections. The role of Tfr cells in breast cancer is not thoroughly investigated. In this study, total circulating CD4 T cells were sorted into CD25+CXCR5 Treg-like, CD25+CXCR5+ Tfr-like, and CD25CXCR5+ Tfh-like subsets. Data showed that the Tfr-like subset presented intermediate levels of both Foxp3 and Bcl-6, while the Treg-like subset was high in Foxp3 and low in Bcl-6, and the Tfh-like was high in Bcl-6 and low in Foxp3. Of note, the frequencies of Tfr-like and Treg-like cells were significantly elevated in breast cancer (BC) patients than in non-cancer (NC) controls. Tfr-like cells in BC patients also expressed significantly higher levels of Foxp3 than those in NC controls. Neither Treg-like nor Tfr-like cells could support Ig production from naive B cells, while Tfh-like cells potently supported Ig production from naive B cells. Tfr-like cells increased the availability of IL-10, both by directly producing IL-10 and by increasing IL-10 production from B cells. Interestingly, Tfr-like cells increased IL-10 production from B cells synergistically with Tfh cells, but at the same time, significantly reduced Ig production in the Tfh-B cell coculture. These Tfr-mediated effects on Tfh cells were not found in canonical Treg cells. Overall, this study demonstrates several distinctive features in circulating Tfr cells and suggests that Tfr cells may promote the formation of IL-10-producing B cells in BC.

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