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991.
Immune response induced by spike protein from transmissible gastroenteritis coronavirus expressed in mouse mammary cells 总被引:1,自引:0,他引:1
The present study is undertaken to investigate the immune response that was induced by the recombinant spike (S) protein from swine-transmissible gastroenteritis virus (TGEV) expressed in mouse mammary cells. A mammary-specific expression vector pEBS containing the full-length cDNA of S gene was constructed and expressed in the mouse mammary cells (EMT6). The recombinant S protein from culture supernatant of transgenic EMT6 was harvested and immunized BALB/c mice. The results demonstrated recombinant S protein was expressed at high levels in mammary cells by Western blotting and enzyme-linked immunosorbent assay (ELISA) detection. The antibody titer in BALB/c mice following immunization with recombinant S protein was detectable after the first immunization. Maximum titers of antibody (8.86+/-0.19 ng/ml of serum) were attained after the second immunization. In conclusion, the recombinant S protein expressed in mammary cells was able to elicit substantial immunological response against TGEV. This lays the basis for using mammary gland bioreactor generating edible vaccine. 相似文献
992.
High-level SLP-2 expression and HER-2/neu protein expression are associated with decreased breast cancer patient survival 总被引:2,自引:0,他引:2
Cao W Zhang B Liu Y Li H Zhang S Fu L Niu Y Ning L Cao X Liu Z Sun B 《American journal of clinical pathology》2007,128(3):430-436
There is sufficient evidence that human stomatin-like protein 2 (SLP-2) is a novel cancer-related gene. Its protein is overexpressed in many human cancers. SLP-2 can contribute to the promotion of cell growth, cell adhesion, and tumorigenesis in esophageal squamous cell carcinoma and lymph node metastasis in laryngeal squamous cell carcinoma. Immunohistochemical detection of SLP-2, estrogen and progesterone receptors, and HER-2/neu were performed on 263 cases of primary invasive breast cancer with a tissue microarray. Of 263 cases, 138 (52.5%) showed high expression of SLP-2 protein, and 125 (47.5%) showed low or absent expression. In addition, there were significant positive associations between tumor stage and size (P = .020), lymph node metastasis (P < .001), clinical stage (P < .001), distant metastasis (P = .002), and HER-2/neu protein expression (P = .037) and high-level SLP-2 expression. High-level SLP-2 expression was associated with decreased overall survival (P = .011) and was more often found in patients with tumors larger than 20 mm, lymph node metastasis, advanced clinical stage, distant metastasis, and HER-2/neu protein-positive expression. More important, lymph node metastasis, HER-2/neu-positive expression, and high-level SLP-2 expression were associated with significantly decreased survival. 相似文献
993.
Cao M Cabrera R Xu Y Firpi R Zhu H Liu C Nelson DR 《Laboratory investigation; a journal of technical methods and pathology》2007,87(6):582-590
Dysfunction of the host immune system in cancer patients can be due to a number of factors, including suppression of tumor-associated antigen reactive lymphocytes by CD4(+)CD25(+) regulatory T (Treg) cells. Several studies suggest that Tregs are elevated in cancer patients and that depletion of Tregs may enhance the antitumor immunity of host, but the pathogenic and mechanistic relationship between cancer and Tregs is still unclear. In this report, we show that Tregs are increased in peripheral blood mononuclear cells (PBMCs) from hepatocellular carcinoma (HCC) patients and positively correlate with tumor burden. When PBMCs are co-cultured with human hepatoma cell lines Huh7, HepG2, and Hclone5, CD4(+)CD25(+)-T cell populations increase in frequency and undergo phenotypic and functional changes. CD45RA, CD45RO, CD69, CD62L, GITR, CTLA-4, Ki67, granzyme A, granzyme B, and FOXP3 expression were upregulated in CD4(+)CD25(+) cells after in vitro exposure to HCC cell lines. CD4(+)CD25(+) T cells from PBMCs that were co-cultured with Huh7 cells also have higher suppressor ability compared to that of the CD4(+)CD25(+) T cells from control PBMC. Huh7 culture supernatants appear to promote CD4(+)CD25(+) T-cell proliferation and inhibit CD4(+)CD25(-) T-cell proliferation. In conclusion, these results strongly suggest that tumor-related factors not only induce and expand CD4(+)CD25(+) cells, but also enhance their suppressor ability. 相似文献
994.
Both Langerhans cells and interstitial DC cross-present melanoma antigens and efficiently activate antigen-specific CTL 总被引:1,自引:0,他引:1
Cao T Ueno H Glaser C Fay JW Palucka AK Banchereau J 《European journal of immunology》2007,37(9):2657-2667
Dendritic cells (DC) have a unique capacity to present external antigens to CD8(+) T cells, i.e. cross-presentation. However, it is not fully established whether the ability to cross-presentation is restricted to a unique subset of DC in humans. Here, we show that two major myeloid DC subsets, i.e. Langerhans cells (LC) and interstitial DC (Int-DC), have the ability to cross-present antigens to CD8(+) T cells in vitro. LC and Int-DC were obtained from DC generated by culturing human CD34(+)-hematopoietic progenitor cells with GM-CSF, FLT3-L, and TNF-alpha (CD34-DC). Both DC subsets were able to capture necrotic/apoptotic allogeneic melanoma cells and present antigens to CD8(+) T cells, resulting in efficient priming of naive CD8(+) T cells into CTL capable of killing melanoma cells. Strikingly, a single stimulation with either subset (LC or Int-DC) or total CD34-DC loaded with necrotic/apoptotic melanoma cells was sufficient to activate melanoma-specific memory CD8(+) T cells obtained from patients with metastatic melanoma to become effective CTL. Thus, this study provides the rationale to use CD34-DC loaded with necrotic/apoptotic allogeneic melanoma cells in a clinical trial. 相似文献
995.
Jin-Lan Zhang Xiao-Hui Huang Hong-Yang Chang Yi Zheng Xue Cao 《Systems biology in reproductive medicine》2018,64(4):266-273
The objective of this study was to explore the association of sperm mitochondrial ND2 (MT-ND2) gene variants with total fertilization failure (TFF). A retrospective comparative study of 246 cases of fresh in vitro fertilization (IVF) cycles or half-intracytoplasmic sperm injection cycles in the Han Chinese population was performed from July 2011 to May 2017. A total of 59 cases undergoing TFF, and 187 control cases with normal fertilization (fertilization rates >50%) were included. The sperm mitochondrial genovariation was determined using nested sequencing. A total of 32 homoplasmic variants and 47 heteroplasmic variants of MT-ND2 gene were observed in this study. There were no significant differences in the frequencies of the 32 homoplasmic variants of MT-ND2 gene between the TFF and control groups. A total of 53 pair-wise comparisons were performed, and the general characteristics of the IVF failure and control subjects were adjusted in logistic models. Data suggested that there were no significant differences in the frequencies of point 4914, 5320, and 5426 heteroplasmic variants of MT-ND2 gene between the TFF and control groups. In addition, no significant difference was observed in the frequency of mtDNA haplogroup D or haplogroup G between the IVF failure group and the normal fertilization group. This study suggests that the MT-ND2 gene variants might not be associated with TFF.
Abbreviations: ATP: adenosine triphosphate; dNTP: deoxy-ribonucleoside triphosphate; FADH2: flavin adenine dinucleotide; FDR: false discovery rate; FSH: follicle-stimulating hormone; IVF: in vitro fertilization; LH: luteinizing hormone; MTATP6: mitochondrially encoded ATP synthase 6; MTCYB: mitochondrially encoded cytochrome b; mtDNA: mitochondrial DNA; MT-ND2: mitochondrial ND2; NADH: nicotinamide adenine dinucleotide; ND2: NADH dehydrogenase subunit 2; OXPHOS: oxidative phosphorylation; PCR: single nucleotide polymorphisms; SNPs: single nucleotide polymorphisms; TFF: total fertilization failure 相似文献
996.
Huynh Nguyen Khanh Tran Thao Quyen Cao Jeong Ah Kim Ui Joung Youn Sanghee Kim Mi Hee Woo Byung Sun Min 《Archives of pharmacal research》2018,41(10):977-985
Five new compounds, 9,3′-dimethoxyhierochin A (1), 6-oxo-trans-neocnidilide (2), (±)-(3E)-trans-6-hydroxy-7-methoxydihydroligustilide (3), (±)-cnidiumin (4), and 6-(1-oxopentyl)-salicylic acid methyl ester (5), together with twenty known compounds (6–25), were isolated from the rhizome of Cnidium officinale. The chemical structures of new compounds were established by NMR spectroscopic techniques, mass spectrometry, Mosher’s method, and CD spectrum. Their anti-inflammatory activities were evaluated against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in macrophage RAW 264.7 cells. Compounds 7, 13, and 14 showed inhibitory effects with IC50 values of 5.1, 24.5, and 27.8 μM, respectively. In addition, compounds 7, 13, and 14 reduced LPS-induced inducible nitric oxide synthase (iNOS) expression and cyclooxygenase-2 (COX-2) protein in a concentration-dependent manner. 相似文献
997.
ShiYue Peng ZuQin Wu Wan Cao YuHan Jian Yue Lu 《Vulnerable children and youth studies》2018,13(4):317-324
This study aims to explore the characteristics and risk factors of cognitive impairment in adolescent patients with first-episode depression. In total, 128 adolescents with first-episode depression were selected (patient group). Clinical factors, including gender, educational level, suicide risk, sleep status based on the Pittsburg Sleep Quality Index scale (PSQI), and disease duration based on Hamilton Rating Scale for Depression (HRSD), were assessed to identify risk factors. The MATRICS Consensus Cognitive Battery (MCCB) was used to assess 50 health subjects (control group). Data were statistically analyzed using the t test, χ2 test, Pearson’s correlation analysis, and stepwise multiple regression analysis in SPSS 22.0. The total MCCB score in the control group was higher than that in the patient group (P < 0.05), while no differences were observed on the maze test, semantic fluency, and continuous operation results (P > 0.05). Cognitive functional impairment in adolescent patients with first-episode depression was related to gender, educational level, suicide risk, sleep disorder, total HRSD score, and disease duration. The stepwise multiple-linear regression analysis obtained the regression equation as follows: Y1 (total MCCB points) = 82.741 + 11.897 × X3 (educational level) – 8.914 × X6 (total HRSD score) – 8.457 × X7 (total disease duration). Cognitive impairment in adolescent patients with first-episode depression was related to their gender, educational level, suicide risk, sleep disorders, HRSD score, and disease duration. Further, educational level, HRSD score, and disease duration were identified as high-risk factors. 相似文献
998.
Recent study suggested that the presence of phytochemicals in food could interact with nanoparticles (NPs) and consequently reduce the toxicity of NPs, which has been attributed to the antioxidant properties of phytochemicals. In this study, we investigated the interactions between ZnO NPs and two flavonoids baicalein (Ba) or baicalin (Bn) as well as the influence of the interactions on the toxicity of ZnO NPs to Caco-2 cells. The antioxidant properties of Ba and Bn were confirmed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays, with Ba being stronger. However, the presence of Ba or Bn did not significantly affect cytotoxicity, intracellular superoxide or release of inflammatory cytokines of Caco-2 cells after ZnO NP exposure. When Ba was present, the cellular viability of Caco-2 cells after exposure to ZnO NPs was slightly increased, associated with a modest decrease of intracellular Zn ions, but these effects were not statistically different. Ba was more effective than Bn at changing the hydrodynamic sizes, Zeta potential and UV–Vis spectra of ZnO NPs, which indicated that Ba might increase the colloidal stability of NPs. Taken together, the results of the present study indicated that the anti-oxidative phytochemical Ba might only modestly protected Caco-2 cells from the exposure to ZnO NPs associated with an insignificant reduction of the accumulation of intracellular Zn ions. These results also indicated that when assessing the combined effects of NPs and phytochemicals to cells lining gastrointestinal tract, it might be necessary to evaluate the changes of colloidal stability of NPs altered by phytochemicals. 相似文献
999.
Duo Cao Lin Liang Yixin Xu Ji Sun Meng Lei Man Wang Yahui Wei Zhenliang Sun 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(3):651-659
Tumor-associated macrophages (TAMs) and angiogenesis are increasingly considered as the pivotal factors that affect tumor progress. Herein, we developed the paclitaxel (PTX)-loaded nanoparticles (NP/PTX) and decorated it with an innovative peptide YI (YINP/PTX) for simultaneously targeting delivery of drug to TAMs and angiogenesis. We demonstrated that the modification of YI peptide significantly enhanced the internalization of nanoparticles by cells and accumulation of nanoparticles in tumor tissues, but down regulated the distribution of them in normal tissues especially the liver. We also made a confirmation that the YI peptide decorated nanoparticles had an excellent co-localization with TAMs and angiogenesis in vivo. Finally, in the HT-26 colorectal tumor-bearing mice, a pharmacodynamic evaluation was performed and results showed that the YINP/PTX was more effective than other PTX formulations in anti-tumor growth. These results together suggested that the prepared nanoparticles are promising in targeting delivery of chemotherapeutics to tumor microenvironment for enhancing tumor therapy effect. 相似文献
1000.
Hanrui Li Ke Li Yunpeng Dai Xinyi Xu Xu Cao Qi Zeng Huyulong He Liaojun Pang Jimin Liang Xueli Chen Yonghua Zhan 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(6):1867-1877
Cancer metastasis is one of the biggest challenges in cancer treatments since it increases the likelihood that a patient will die from the disease. Therefore, the availability of techniques for the early detection and quantification of tumors is very important. We have prepared cyanine 7.5 NHS ester (Cy7.5) and folic acid (FA) conjugated biodegradable mesoporous silica nanoparticles (bMSN@Cy7.5-FA NPs) (~100 nm) for visualizing tumors in vivo. The fluorescence spectra revealed that the emission peak of bMSN@Cy7.5-FA NPs had a red-shift of 1 nm. Confocal immunofluorescent images showed that bMSN@Cy7.5-FA NPs had an excellent targeting ability for visualizing cancer cells. In vivo fluorescence imaging has been conducted using an orthotopic model for pancreatic cancer within 48 h, and the fluorescence intensity reached a maximum at a post injection time-point of 12 h, which demonstrated that the use of bMSN@Cy7.5-FA NPs provides an excellent imaging platform for tumor precision therapy in mice. 相似文献