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101.
γδ T cells represent one unique recognition pattern, the limited recognition, which distinguishes from the specific recognition for αβ T cells and pattern recognition for macrophages. Vδ1 γδT cell is the major subset of human γδT cells, which predominates in mucosal tissue including the intestinal epithelia. Presently, a few antigens that human Vδ1TCR can recognize have been identified. Among them, MHC class I chain-related molecules A (MICA) have been studied most intensively. Besides Vδ1TCR, MICA is also the ligand of NKG2D, a C-type lectin-like activating immunoreceptor. In human, only Vδ1 cells can simultaneously express both types of receptors of MICA while NK cells, αβ T cells and other subsets of γδT cells likewise express NKG2D. Although the precise mechanisms are still enigmatic, this distinct pattern of Vδ1 cells recognizing MICA predicts unique biological significance of Vδ1 cells in immune defense. Recent years, some progresses have been made in this issue. In this review we summarize the related reports and put forward some novel views based on our group's studies. 相似文献
102.
Immunoprophylaxis of Chlamydia trachomatis lymphogranuloma venereum pneumonitis in mice by oral immunization. 下载免费PDF全文
Groups of BALB/c mice were orally immunized with chlamydiae and challenged intranasally to determine whether oral immunization offers protection against pulmonary disease and to characterize the nature and kinetics of the chlamydial antibody response in the lung and other mucosal sites. Protection by oral immunization from chlamydial lung disease was demonstrated by lack of replication of the organism and the lack of chlamydial antigen in lung tissue. The chlamydial immunoglobulin A (IgA) antibody response was present at all body sites, reaching peak levels in the lung as well as in the serum. Classical IgA booster effect kinetics was observed after intranasal challenge, especially in the lung. Specific IgG antibody was detected at all body sites but at lower levels. Furthermore, animals immunized orally had no pneumonic process, as determined by histopathology. These studies also suggest that passively acquired specific serum IgG antibody may not significantly influence the course of mucosal replication of the organism. These observations indicate that oral immunization activating the gut-associated lymphoid tissue system gave total protection against chlamydial lung disease, suggesting migration of immunologically competent cells from the intestine to the lung. 相似文献
103.
Cortical spreading depression (SD) is characterized by propagation of neuronal/glial membrane depolarization throughout the unilateral cerebral cortex and has been linked to several neurological disorders, including migraine aura and epilepsy. SD induction resulted in a dramatic increase in BrdU-incorporated cells in the ipsilateral cortical hemisphere that was dependent on the number of elicited SD. Immunohistochemical studies revealed that 53% of the BrdU-labeled cells in the SD-generated cortex were NG2 immunopositive and 25% were OX-42 immunopositive. The remaining 22% of BrdU-incorporated cells showed no immunoreactivity to GST-rr, GFAP, NeuN, NG2 or OX-42.These data indicate that functional excitation of the cerebral cortex induces proliferative response in cortical cells, which may subsequently differentiate into glial progenitor or microglia within 3 days after stimulation. 相似文献
104.
S. Sharmin M. Shiota E. Murata P. Cui H. Kitamura M. Yano H. Kido 《Inflammation research》2002,51(4):195-200
OBJECTIVE AND DESIGN: Investigation of the role of a novel inflammatory mediator 31-amino acid endothelin-1 [ET-1 (1-31)], a major ET derivative in granulocytes, in eosinophil recruitment after its subcutaneous administration to mice. METHODS: Various ET-1 derivatives (100 pmol), with or without ET receptor antagonists (200 pmol), were administered subcutaneously to mice, and then the eosinophil migration into and chemokine levels in the injected loci were analyzed. RESULTS: ET-1 (1-31) and a 21-amino acid endothelin-1 (ET-1), but not big ET-1, induced eosinophil migration into the injected loci with a peak after administration for 12 h, and increased the levels of eotaxin and interleukin-5 with peaks at 6 and 24 h, respectively. These effects of ET-1(1-31) and ET-1 were significantly inhibited by an ETA receptor antagonist, BQ-123, but not by an ETB receptor antagonist, BQ-788. CONCLUSION: Novel bioactive ET-1 (1-31) induces local eosinophil migration, and increases in eotaxin and interleukin-5 through an ETA or ETA-like receptor. 相似文献
105.
106.
目的通过对多囊卵巢综合征(PCOS)妇女的生长分化因子9(GDF-9)基因的突变分析,探索GDF-9基因与PCOS的发病机制的关系。方法对120例PCOS患者釉80例正常对照的GDF-9基因进行聚合酶链反应(PCR)特异扩增,应用单链构象多态性(SSCP)分析和DNA测序方法检测基因突变。结果PCOS患者的GDF-9的所有外显予均未发现错义突变。结论GDF-9因子的DNA变异可能与PCOS的发病没有相关关系。研究PCOS患者的GDF-9的mRNA与蛋白表达水平与其发病的关系可能是今后的研究方向。 相似文献
107.
108.
实验用foS蛋白免疫组织化学方法,研究了中枢神经系统兴奋性介质N-氨基-D-门冬氨酸诱导大鼠下丘脑内c-fos的表达.N-氨基-D-门冬氨酸注射大鼠皮下后,观察了fos阳性细胞在下丘脑内开始出现与消失的时程相关以及在下丘脑内的分布.结果表明:给N-氨基-D-门冬氨酸后30分开始出现fos阳性细胞,1~2小时达高峰,4~8小时消失.fos阳性细胞主要分布于视上核、室旁核和弓状核,视上核和室旁核中fos阳性细胞分别占细胞总数的57.8%和63.6%,在弓状核中占细胞总数的60.6%. 相似文献
109.
Human granulocyte-macrophage colony-stimulating factor (hGM-CSF): identification of a binding site for a neutralizing antibody. 总被引:2,自引:0,他引:2
E Nice P Dempsey J Layton G Morstyn D F Cui R Simpson L Fabri A Burgess 《Growth factors (Chur, Switzerland)》1990,3(2):159-169
One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition. 相似文献
110.
目的研究经单侧椎弓根穿刺椎体后凸成形术治疗侧方骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCF)的疗效。方法选择我院2009年10月~2011年10月收治的30例侧方OVCF患者,随机行凹侧或双侧球囊撑开椎体后凸成形术治疗,分别在术后1、6、12个月进行随访,对椎体高度恢复、脊柱后凸、侧凸Cobb角及并发症进行评价。结果术后1、6、12个月的随访结果比较发现,凹侧撑开及双侧撑开组患者椎体高度均较术前明显恢复(P0.05),脊柱后凸、侧凸Cobb角均较术前明显纠正(P0.05)。术后定期随访无丢失。凹侧撑开组与双侧撑开组之间比较,上述指标差异无统计学意义(P0.05)。结论经凹侧球囊撑开椎体成形治疗侧方OVCF,与双侧撑开相比疗效相当,可简化手术、缩短手术时间、减小创伤、减少费用,是治疗侧方OVCF的有效方式。 相似文献