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101.
妊娠17~37周胎儿可溶性白介素2受体和NK细胞含量的变化 总被引:1,自引:0,他引:1
目的:探讨妊娠17~37周正常和宫内感染时胎儿外周血可溶性白介素2受体(Soluble interleuldn-2 receptor,sIL-2R)和自然杀伤细胞(Natural killer,NK)含量的变化。方法:超声引导下行脐带穿刺术,收集129例胎儿外周血,包括97例正常对照组胎儿血,32例宫内感染组(单纯疱疹病毒感染、弓形虫感染、风疹病毒感染)胎儿血,采用双色免疫荧光标记流式细胞仪技术测定胎JLPF周血NK细胞百分率,双抗体夹心酶联免疫吸附试验测定胎JLPF周血中sIL-2R的含量,分析生理状态下胎儿外周血NK细胞、sIL-2R的状况和宫内感染时NK细胞和sIL-2R含量的变化。结果:妊娠17—37周胎儿外周血NK细胞、sIL-2R含量不随孕周改变,r(NK)=-0.03,P〉0.05;r(sIL-2R)=0.167,P〉0.05,宫内感染时NK细胞含量减少,sIL-2R含量增多,与正常对照组相比差异有显著意义;t(NK)=4.29,P〈0.01;t(sIL-2R)=-5.833,P〈0.01。结论:妊娠17—37周胎儿外周血有一定量的NK细胞和sIL-2R存在,但机体免疫功能仍不完善,宫内感染时机体容易出现免疫抑制状态。 相似文献
102.
Hematopoiesis is regulated by a variety of signals that either originate within a developing cell or are supplied by the surrounding environment in secreted- or contact-dependent forms. This review discusses the effects of one secreted factor, interleukin-7, on the development of B lymphocytes. We describe a molecular mechanism for a crucial checkpoint during B lineage maturation, based on the integration of signals mediated by the pre-B cell receptor, the interleukin-7 receptor, and the environment in which these signals are received. 相似文献
103.
Takahashi HK Xue D Iwagaki H Tamura R Katsuno G Yagi T Yoshino T Mori S Nishibori M Tanaka N 《Clinical immunology (Orlando, Fla.)》2005,115(1):85-92
Prostaglandin E1 (PGE1) has therapeutic value for transplantations due to its microvascular activity. Interleukin (IL)-18, which is elevated in plasma during the acute rejection after organ transplantation, elicits the expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2, CD40, and CD40 ligand (CD40L) on monocytes as well as the production of interferon (IFN)-gamma and IL-12 and proliferation of T-cells during the human mixed lymphocyte reaction (MLR) in an in vitro model of acute rejection. In contrast, PGE1 inhibits all the adhesion molecule expression, cytokine production and T-cell proliferation in the presence of IL-18. The effects of PGE1 depend on stimulation of the IP/EP2/EP4-receptor, and thus, PGE1 might have therapeutic potential for treating acute rejection due to its immune regulatory effect. 相似文献
104.
Ito Y Kawamura I Kohda C Tsuchiya K Nomura T Mitsuyama M 《International immunology》2005,17(12):1597-1606
Seeligeriolysin O (LSO), a member of cholesterol-dependent cytolysins of Listeria seeligeri, exhibits cytokine-inducing activity. In this study, we examined the profile of cytokines expressed in macrophages of mice after stimulation with full-length form of recombinant LSO (rLSO530), C-terminal-truncated protein (rLSO483) and two authentic cytokine-inducing Toll-like receptor (TLR) ligands from bacteria, peptidoglycan (PGN) and LPS. Both rLSO530 and rLSO483 were able to induce IL-12 p40 and IL-12 p70 more strongly in macrophages than PGN or LPS. In contrast, IFN-beta and nitric oxide were induced by LPS but not by rLSO530, rLSO483 or PGN. In the presence of exogenously added IFN-beta, IL-12 p40 and IL-12 p70 production was inhibited after LSO stimulation, but IL-12 p70 production was enhanced after PGN stimulation. Although LSO signaling appeared to be associated with both TLR2 and TLR4, the profile of cytokine production by LSO stimulation was distinct from those by stimulation with PGN or LPS. Thus, it was shown that LSO is a unique bacterial ligand that induces macrophage cytokine production in a manner different from PGN or LPS. 相似文献
105.
Shannon G. Farmakis Ann M. Barnes John C. Carey Stephen R. Braddock 《American journal of medical genetics. Part A》2019,179(3):455-466
The purpose of this study was to determine whether trisomy 18 patients are at an increased risk of tumor development and require formal tumor screening recommendations. A literature search of trisomy 18 patients with reports of tumors or malignancies, and compilation of all previously reported as well as new unreported cases was performed. 67 patients with trisomy 18 were found to have documented malignancies. 44 patients had hepatoblastomas, 21 patients had Wilms tumors, one patient had a functional neurogenic neoplasia, and one patient had Hodgkins lymphoma. The increasing numbers of reported malignancies in patients with trisomy 18 supports the indication for an early screening process. Specific screening recommendations are outlined consisting of imaging exams and laboratory values performed at specific intervals. 相似文献
106.
Kupffer cell-mediated cytotoxicity against hepatoma cells occurs through production of nitric oxide and adhesion via ICAM-1/CD18 总被引:1,自引:0,他引:1
Saito Hidetsugu; Kurose Iwao; Ebinuma Hirotoshi; Fukumura Dai; Higuchi Hajime; Atsukawa Kazuhiro; Tada Shinichiro; Kimura Hiroyuki; Yonei Yoshikazu; Masuda Tetsuya; Miura Soichiro; Ishii Hiromasa 《International immunology》1996,8(7):1165-1172
Rat Kupffer cell (KC)-mediated cytotoxicity against both thesyngeneic hepatoma cell line AH70 and hepatocytes was evaluatedby changes in mitochondrial function, and the possible roleof ICAM-1/CD18 in the interaction between the cells was studied.Rhodamine 123 fluorescence, a marker of the mitochondrial membranepotential, decreased in AH70 cells after co-culture with KC,while that in hepatocytes was unchanged by co-culture. Thisdecrease was blocked by anti-ICAM-1, anti-CD18 and the Inhibitionof nitric oxide synthesis. Cytometric studies demonstrated thatICAM-1 expression on AH70 cells increased after addition ofIFN-, IL-1ß, tumor necrosis factor (TNF)- or KC, whilein hepatocytes ICAM-1 was not increased. Anti-ICAM-1 pretreatmentinhibited the increase in ICAM-1 expression and the decreasein rhodamine 123 fluorescence on AH70 cells after co-culturewith KC. CD18 on KC was increased only after co-culture withAH70. TNF- but not IFN- was detected in the supernatant of co-culturebetween KC and AH70 cells, and this production was partiallyinhibited by anti-ICAM-1 and anti-CD18. The activity of Induciblenitric oxide synthase in Kupffer cells and the levels of nitritesand nitrates in the co-culture supernatant increased over time,and this increase was attenuated either by addition of NO synthesisinhibitors, anti-ICAM-1 or anti-CD18. These results indicatethat the rat KC causes mitochondrial dysfunction in cancer cellsvia the production of NO and cell-to-cell adhesion via ICAM-1/CD18has an Important role in this cytotoxic process. 相似文献
107.
Prevention of endotoxin shock by an antibody against leukocyte integrin {beta}2 through inhibiting production and action of TNF 总被引:2,自引:0,他引:2
Watanabe Shun-ichi; Mukaida Naofumi; Ikeda Naoki; Akiyama Mariko; Harada Akihisa; Nakanishi Isao; Nariuchi Hideo; Watanabe Yoh; Matsushima Kouji 《International immunology》1995,7(7):1037-1046
Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans. 相似文献
108.
Øivind Øines Thomas Schram 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(1):93-105
Two mitochondrial and one nuclear genetic marker were used to study the phylogenetic position of the two reported CO1-genotypes
of Caligus elongatus in a group of closely related caligid parasites. Molecular analysis of the two mitochondrial genes (CO1 and 16S), indicate
genetic distances of the two C. elongatus genotypes in the lower range of distances previously reported between other crustacean species, but higher than comparable
reported within-species differences. Analyses of nuclear 18S sequences indicate no detectable differentiation between these
genotypes, but may be due to expected differences in the resolution of these genetic markers. Investigation of two of three
selected morphological characters reveals phenotypes supporting the division based on the molecular division. The species
status on the two C. elongatus genotypes cannot be drawn conclusively, although the molecular and morphological data presented here suggests the presence
of sibling species. 相似文献
109.
Saiki O Uda H Nishimoto N Miwa T Mima T Ogawara T Azuma N Katada Y Sawaki J Tsutsui H Matsui K Maeda A Nakanishi K 《Clinical immunology (Orlando, Fla.)》2004,112(1):120-125
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile. 相似文献
110.
Demonstration of the presence of IL-16, IL-17 and IL-18 at the murine fetomaternal interface during murine pregnancy 总被引:6,自引:0,他引:6
Ostojic S Dubanchet S Chaouat G Abdelkarim M Truyens C Capron F 《American journal of reproductive immunology (New York, N.Y. : 1989)》2003,49(2):101-112
PROBLEM: To determine if interleukin-16 (IL-16), IL-17, and IL-18 are present at the murine fetomaternal interface during pregnancy as a first step towards investigating their roles in fetomaternal relationship. METHODS: Expression of IL-16, IL-17, and IL-18, was assessed by immunohistochemistry (IHC) in the BALB/c x BALB/k (H2d x H2k), and the CBA/J x BALB/c non-abortion prone, and CBA/J x DBA/2 abortion prone matings. Enzyme-linked immunosorbent assay (ELISA) were performed for the two latter cytokines to compare local production in the abortion prone CBA/J x DBA/2 versus the non-abortion prone CBA/J x BALB/c matings. RESULTS: Expression of IL-17 was borderline. The anti-IL-16 staining specifically localized in the uterine stroma and glandular epithelium and was rather low in the placenta. IL-18 staining started in the peri-implantation uterus in the basal proliferative stroma, and was also traced, although weaker, in the glandular epithelium. In the immediate post-implantation period, a weak stromal staining persisted but there was a strong labeling of the ectoplacental cone. Interestingly, when the ectoplacental cone differentiates into placenta having a major histocompatibility complex (MHC) class I + spongiotrophoblast and a (MHC class I-) labyrinth, a very strong transient labeling of uterine natural killer (u-NK) cells was found. Later in gestation, IL-18 was also produced by giant cell and spongiotrophoblast. Finally, we compared by ELISA the production of IL-17/-18 in CBA/J x DBA/2 and CBA/J x BALB/c matings. We detected significantly more IL-18 in the non-abortion prone combination decidua or placenta. CONCLUSION: The three cytokines IL-16, IL-17, and IL-18 were detected at the fetomaternal interface with a tissue specific, stage-dependent distribution. The predominance of IL-18 secretion in the non-resorption prone matings lead us to question the general validity of the classical T-helper (Th)1/2 paradigm. 相似文献