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61.
Induction of cytotoxic T lymphocytes in vivo with protein antigen entrapped in membranous vehicles. 总被引:7,自引:0,他引:7
Intravenous administration of APC such as splenocytes loaded with a soluble protein Ag has been shown to prime for an Ag-specific CTL response. It is thought that the APC directly presents loaded Ag in a MHC-restricted manner. However, it is demonstrated in this study that allogeneic splenocytes, MHC-free RBC, and even synthetic lipid vesicles (liposomes) after loading with OVA can elicit an OVA-specific and MHC-restricted CTL response. Biodistribution studies of these Ag-associated vehicles showed that the liver, spleen, and lung were the major organs responsible to scavenge these carriers, suggesting that the monocyte-macrophage system was involved in the Ag presentation for CTL. Depletion of macrophages by a specific macrophage killer, Cl2MDP, containing liposomes, abolished the CTL induction by immunization with OVA Ag carried by these vehicles except the induction by syngeneic splenocytes. Thus, the syngeneic splenocytes present Ag directly to the T cells, but other membranous vehicles carry the Ag to the host APC including macrophages, which then present it to the T cells. These results indicate that formulation of an Ag in membranous/colloidal vehicles may be a way to prime for a CTL response. 相似文献
62.
63.
Chih-Chin Shih Chuan-Chin Huang Shou-Hsien Li Mei-Hsiu Hwang Ling-Ling Lee 《Conservation Genetics》2009,10(6):1845-1847
Ten polymorphic microsatellite markers were developed for the endangered Formosan black bear (Ursus thibetanus formosanus) from a partial genomic library enriched for GAAA repeat. Polymorphism of these loci was evaluated in 27 Formosan black bear
specimens of unknown relationship. The number of alleles per locus ranged from 5 to 15 and the observed heterozygosity of
each locus ranged from 0.556 to 0.889. These loci should provide useful molecular tools to study conservation genetics of
the Formosan black bear and other Asiatic black bears. 相似文献
64.
Chen Chen Raymond Dagnino Jr. Charles Q. Huang James R. McCarthy Dimitri E. Grigoriadis 《Bioorganic & medicinal chemistry letters》2001,11(24):3165-3168
Cyclizations of alkylhydrazines with N-acyl-S-methylisothioureas, readily synthesized from acyl chlorides, sodium thioisocyanate, dialkylamines then methyl iodide in a one-pot reaction, gave 1-alkyl-3-dialkylamino-5-phenyltriazoles 7 as major products. The regioisomers were assigned through the use of NOE NMR experiments. While bearing a N-bis(cyclopropyl)methyl-N-propylamino group, this series of compounds shows very good binding affinity on the human CRF1 receptor. Among them, 1-methyl-3-[N-bis(cyclopropyl)methyl-N-propylamino]-5-(2,4-dichlorophenyl)-1H-[1,2,4]triazole 7a had the best binding affinity for the CRF1 receptor (Ki=9 nM). 相似文献
65.
Hui-bin Zhang Ya-an Zhang Guan-zhong Wu Jin-pei Zhou Wen-long Huang Xiao-wen Hu 《Bioorganic & medicinal chemistry letters》2009,19(6):1740-1744
A novel class of sulfonylurea and thiourea derivatives substituted with benzenesulfonamide groups were designed and synthesized. The target compounds were assayed for the effects on the insulin release of isolated rat pancreatic islets and the glucose transport in adipocytes of rats. Some of them exhibited high potency. Compound 10 also had potent antiplatelet activity and showed an excellent property to protect collagen–epinephrine-induced mice mortality as well as plasma glucose-lowering activity in vivo. The preliminary pharmacological profile of compound 10 showed that it might be useful in the treatment of diabetics with cardiovascular and nephropathy complications. 相似文献
66.
Background
Eosinophilia plays the major role in the pathogenesis of asthma and correlates with the up‐regulation of eotaxin, which, together with interleukin (IL)‐5, is important for differentiation, chemo‐attraction, degranulation, and survival of eosinophils in local tissue. In a previous study, we found that administration of lentivirus‐delivered short hairpin RNA (shRNA) to suppress the expression of IL‐5 inhibited airway inflammation. The present study aimed to investigate the role of eotaxin shRNA and the synergistic effect of eotaxin and IL‐5 shRNAs on airway inflammation in an ovalbumin (OVA)‐induced murine model of asthma.Methods
Lentivirus‐delivered shRNAs were used to suppress the expression of eotaxin and/or IL‐5 in local tissue in an OVA‐induced murine asthma model.Results
Intra‐tracheal administration of lentivirus containing eotaxin shRNA expressing cassette (eoSEC3.3) efficiently moderated the characteristics of asthma, including airway hyper‐responsiveness, cellular infiltration of lung tissues, and eotaxin and IL‐5 levels in bronchio‐alveolar lavage fluid. Administration of lentiviruses expressing IL‐5 or eotaxin shRNAs (IL5SEC4 + eoSEC3.3) also moderated the symptoms of asthma in a mouse model.Conclusions
Local delivery of lentiviruses expressing IL‐5 and eotaxin shRNAs provides a potential tool in moderating airway inflammation and also has the potential for developing clinical therapy based on the application of shRNAs of chemokines and cytokines involved in T helper 2 cell inflammation and eosinophilia. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献67.
Zengfeng Ma Gang Qin Yuexiong Zhang Chi Liu Minyi Wei Zhenlu Cen Yong Yan Tongping Luo Zhenjing Li Haifu Liang Dahui Huang Guofu Deng 《The Plant journal : for cell and molecular biology》2021,107(4):1084-1101
Bacterial leaf streak (BLS) is a major bacterial disease of rice. Utilization of host genetic resistance has become one of the most important strategies for controlling BLS. However, only a few resistance genes have been characterized. Previously, a recessive BLS resistance gene bls1 was roughly mapped on chromosome 6. Here, we further delineated bls1 to a 21 kb region spanning four genes. Genetic analysis confirmed that the gene encoding a mitogen-activated protein kinase (OsMAPK6) is the target of the allelic genes BLS1 and bls1. Overexpression of BLS1 weakened resistance to the specific Xanthomonas oryzae pv. oryzicola (Xoc) strain JZ-8, while low expression of bls1 increased resistance. However, both overexpression of BLS1 and low expression of bls1 could increase no-race-specific broad-spectrum resistance. These results indicate that BLS1 and bls1 negatively regulate race-specific resistance to Xoc strain JZ-8 but positively and negatively control broad-spectrum resistance, respectively. Subcellular localization demonstrated that OsMAPK6 was localized in the nucleus. RGA4, which is known to mediate resistance to Xoc, is the potential target of OsMAPK6. Overexpression of BLS1 and low expression of bls1 showed increase in salicylic acid and induced expression of defense-related genes, simultaneously increasing broad-spectrum resistance. Moreover, low expression of bls1 showed increase an in jasmonic acid and abscisic acid, in company with an increase in resistance to Xoc strain JZ-8. Collectively, our study provides new insights into the understanding of BLS resistance and facilitates the development of rice host-resistant cultivars. 相似文献
68.
Xiaoqing Wu Xiaorui Xie Linjuan Su Na Lin Bin Liang Nan Guo Qingquan Chen Liangpu Xu Hailong Huang 《Journal of cellular and molecular medicine》2021,25(18):8929-8935
Pallister-Killian syndrome (PKS) is a rare sporadic genetic disorder usually caused by mosaicism of an extra isochromosome of 12p (i(12p)). This retrospective study analysed the prenatal ultrasound manifestations and molecular and cytogenetic results of five PKS foetuses. Samples of amniotic fluid and/or cord blood, skin biopsy and placenta were collected. Conventional karyotyping and single nucleotide polymorphism array (SNP array) were performed on all the amniotic fluid or cord blood samples. Copy number variants sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were also used for the validation for one foetus. All the five foetuses were from pregnancies with advanced parental age. Two foetuses involved structural abnormalities and one foetus had only soft markers, all of which included increased nuchal translucency. The rest two foetuses had normal ultrasounds in the second trimester, which has rarely been reported before. The karyotype revealed typical i(12p) in four cases and a small supernumerary marker chromosome consisting of 12p and 20p in the remaining one case. The proportion of cells with i(12p) ranged from 0 to 100% in cultural cells, while SNP array results suggested 2−4 copies of 12p. For one foetus, metaphase FISH showed normal results, but the interphase FISH suggested cell lines with two, three and four copies of 12p in the amniotic fluid. Advanced parental age may be an important risk factor for PKS, and there were no typical ultrasound manifestations related to PKS. A combination of karyotype analysis and molecular diagnosis is an effective method for the diagnosis of PKS. 相似文献
69.
70.