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1.
Equine herpesvirus type 1 (EHV-1) is responsible for respiratory disorders, abortion and myeloencephalopathy (EHM) in horses. Two pathotypes of EHV-1 strains are circulating in the field: neurovirulent (N) and non-neurovirulent (NN). For both strains, CD172a+ monocytic cells are one of the main carrier cells of EHV-1 during primary infection, allowing the virus to invade the horse’s body. Recently, we showed that EHV-1 NN strains showed a restricted and delayed replication in CD172a+ cells. Here we characterize the in vitro replication kinetics of two EHV-1 N strains in CD172a+ cells and investigate if the replication of these strains is similarly silenced as shown for EHV-1 NN strains. We found that EHV-1 N replication was restricted to 7–8% in CD172a+ cells compared to 100% in control RK-13 cells. EHV-1 N replication was not delayed in CD172a+ cells but virus production was significant lower (103.0 TCID50/105 inoculated cells) than in RK-13 cells (108.5 TCID50/105 inoculated cells). Approximately 0.04% of CD172a+ cells produced and transmitted infectious EHV-1 to neighbour cells compared to 65% of RK-13 cells. Unlike what we observed for the NN strain, pretreatment of CD172a+ cells with histone deacetylases inhibitors (HDACi) did not influence the replication of EHV-1 N strains in these cells. Overall, these results show that the EHV-1 replication of N strains in CD172a+ cells differs from that observed for NN strains, which may contribute to their different pathogeneses in vivo. 相似文献
2.
AIM: To confirm the existence of the endothelial progenitor cells in human cord blood and to study its differentiation and development process. METHODS: The mononuclear cells in human cord blood were isolated using lymphocyte separation solution. Then the mononuclear cells were cltured in MCDB131 containing 20% fetal bovine serum. The effects of 5 μmol/L dexamethasone, the extract from bovine brain, insulin and hypoxanine on the proliferation and differentiation of the adherent cells were observed. The morphology of the adherent cells were examined twice daily by inverted phase contrast microscope. CD34 and CD14 expression were determined by FACS. Immunohistochemistry was used to confirm the expression of factor Ⅷ. RESULTS: The proliferative endothelial progenitor cells existed within the CD34-adherent mononuclear cells of human cord blood. Dexamethasone and hypoxanine decreased the number of spindle-shaped cells and caudated cells. Bovine brain extract, insulin and FCS enhanced the number of spindle-shaped cells and caudated cells. CONCLUSION: The existence of endothelial progenitor cells within the CD34 - adherent monouclear cells of the human cord blood was observed and these cells were able to differentiate into endothelial-like cells in vitro. 相似文献
3.
AIM: To investigate expression of CD44s in lung cancer and it's clinical significance. METHODS: A total of 117 primary lung cancer from patients were examined for CD44s expression by immunohistochemical staining. RESULTS: CD44s mostly expressed in non-small cell lung cancer (NSCLC) but not in small ecll lung cancer (SCLC), and squamous cell carcinoma(SCC) showed much stronger expression of CD44s than adenocarcinoma(ADC)(P<0.05). In comparison of the lung cancer with/ without lymph node metastasis, the latter showed stronger expression of CD44s(P<0.01). According to TNM, there was a distinct statistic difference between early stage and advanced stage(P<0.05). CONCLUSION: CD44s might be a better indicant in histological classification of lung cancer, lymph node metastasis, clinical stage and prognosis. 相似文献
4.
AIM: To explore the ex vivo expansion characteristics of the endothelial progenitor cells (EPCs). METHODS: CD34+ cells were selected from umbilical cord blood mononuclear cells (MNC) by MiniMACS system, expanded at the same conditions as that for total MNC, coincubation of CD34+ and CD34- from the same donation for EPCs. In addition, we tested the effect of vessel endothelial growth factor (VEGF) and passage on cell differentiation, expansion kinetics and apoptosis. EPCs were determined and quantified by immunocytochemistry and flow cytometry. RESULTS: Coculture of CD34+ and CD34-,total MNC led to a significant increase in the expansion of CD34+ cells compared with CD34 enrichment (P<0.05). There was a trend toward decreased apoptosis in cultures when early passage was performed once the linear cord like structures appeared. There was no significant effect on apoptosis between with VEGF and without VEGF group (P>0.05). These differentiated EPCs were stained positive for CD34+, von Willebrand factor (vWF), KDR, CD31 and incorporate acetylated low-density lipoprotein (LDL). CD34+ and AC133+cells accounted for 68.2%±6.3% (n=6) and 57.2%±9.8% (n=6) of attaching (AT) cells at day 7 of culture, respectively. CONCLUSIONS: Coculture of CD34+ and CD34- or culture of MNC enhances ex vivo expansion of EPCs. Early passage decreases apoptosis rate, VEGF has no significant effect on ex vivo expansion of EPCs. 相似文献
5.
AIM: To investigate the anti-metastasis effect of weimaining, extracted from fragopyrum cymosum meissn, a Chinese medicine, on murine Lewis lung carcinoma (3LL). METHODS: The anti-metastasis effect of weimaining in vivo was detected in the grafting lung metastasis model of murine Lewis lung carcinoma. The effects of the drug on the expression of CD34 and E-cadherin were investigated by immunohistochemical staining and RT-PCR. RESULTS: Weimaining effectively inhibited the lung metastasis of 3LL at a concentration of 250 mg·kg-1·d-1, significantly suppressed the expression of CD34 and increased the expression levels of E-cadherin protein and mRNA in 3LL cells. CONCLUSIONS: Weimaining inhibits the metastasis of murine Lewis lung carcinoma (3LL) in vivo via increasing the expression of E-cadherin and decreasing microvessel density of tumor tissue. 相似文献
6.
AIM: To study the effect of propolis on the expression of CD54 and activation of NF-κB p65 in lung tissue of acute lung injury (ALI) rats. METHODS: 40 male Wistar rats were divided into 5 groups: normal control, model control, dectancyl group, water soluble derivative of propolis (WSP) group and ethanol extracted propolis (EEP) group. ALI animal model was performed by oleic acid and LPS twice attack. The pathologic slice was observed with light microscope and the NF-κB p65 activity and CD54 expression were tested by immunohistochemistry (SABC and SP). RESULTS: Both EEP and WSP antagonized the lung edema, decreased the inflammation and inhibited the expression of CD54 and activation of NF-κB p65. CONCLUSION: The increase in the expression of CD54 and the activation of NF-κB p65 in the lung tissues of ALI were involved in the formation of ALI. Propolis ameliorated the lung damage, which maybe related to the inhibition of CD54 expression and NF-κB p65 activation. 相似文献
7.
M. G. Wagener S. Leonhard‐Marek J.‐D. Häger C. Pfarrer 《Anatomia, histologia, embryologia》2018,47(3):268-270
Mastitis is a common economically relevant problem in dairy farming. As the major entry for pathogens is the papillary duct, one of the first defence mechanisms is the teat sphincter. This sphincter shows a rhythmic contractility of yet unknown origin. Searching for possible modulatory pacemaker cells, teat sphincters of eight cows were stained immunohistochemically with antibodies against CD117 and vimentin and evaluated microscopically for the presence of telocytes. CD117‐ and vimentin‐positive telocytes with telopodes were found in close contact with smooth muscle cells. Our findings present a first evidence of telocytes in the teat of bovines. 相似文献
8.
9.
AIM: To study cellular and molecular mechanism involved in increasing susceptibility of infection in psychological stress persons. METHODS: Comparative studies were performed with double staining and flow cytometry analysis on immunophenotyping and in vitro expression of early activating surface molecule CD69 in response to mitogens on T cells from peripheral blood of 20 healthy college student volunteers before and after psychological stress. A series of term final examinations was defined as psychological stress. RESULTS: Immunophenotyping analysis showed no statistically significant difference in the percentage of CD2, CD3, CD4, CD8, CD19, CD20, CD16 and CD56 positive lymphocyte populations before and after psychological stress. There was a statistically significant decrease in the in vitro expression of CD69 in response to polyclonal stimulators on the T cells from persons after psychological stress than those before psychological stress. The percentage of CD69 expression (CD69+CD3+/CD3+%) in response to PHA and PDB in the whole blood culture for 72 hours decreased respectively from 28.1±4.1 and 80.7±6.8 on the T cells obtained before psychological stress to 17.6±3.8 and 65.8±7.9 on those obtained after psychological stress, while there was no statistically significant difference between the CD69 expression rates without stimulators on the T cells obtained before and after psychological stress. CONCLUSIONS: The effects of psychological stress to immune system is not on the level of changing proportions of the sub-populations within peripheral blood lymphocytes. Psychological stress can decrease the activating response of T cells in healthy persons, which may be responsible for the increase of susceptibility to infection in the psychological stress persons. 相似文献
10.
AIM:To investigate expression and function of CD40 ligand by peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE).METHODS:Expression of CD40 ligand by PBMCs in patients with SLE and control were examined by flow cytometric analysis before and after stimulated by phytohemagglutinin(PHA)and depressed by Dexamethasone(Dex). The correlation between expression of CD40 ligand and SLE activity index(SLEDAI) was analysed in patients with SLE.RESULTS:The expression of CD40 ligand by PBMCs in patients with active SLE was higher than that in patients with inactive SLE and control. Though the expression of CD40 ligang by PBMCs could be stimulated by PHA in three groups, it was the highest in patients with active SLE. Dex depressed the expression of CD40 ligand by PBMCs significantly in patients with SLE, but not in control. There was high positive correlation between expression of CD40 ligand and SLEDAI in patients with active and inactive SLE.CONCLUSION:Increased expression of CD40L by PBMCs in patients with SLE may play an important role in pathogenesis of SLE. 相似文献