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131.
目的 探讨可溶性 HLA-G1(sHLA-G1)对人 NK-92 细胞杀伤活性的抑制与细胞表面免疫球蛋白样转录分子 2(ILT2)和杀伤细胞免疫球蛋白样受体 2DL4(KIR2DL4)受体的关系。 方法 ①通过原核表达技术获得 sHLA-G1 重组蛋白(重组蛋白),并采用蛋白质印迹法进行鉴定。②取 NK-92 细胞,加入终浓度 20 μg/ml 的重组蛋白分别培养 10、30 min,再分别加入抗 HLA-G1/G5、抗ILT2 和抗 KIR2DL4 抗体,采用流式细胞术检测各组 NK-92 细胞表面 sHLA-G1 和 ILT2、KIR2DL4 受体表达阳性率;以 NK-92 细胞单独培养作为对照组。③以人白血病 K562 细胞为靶细胞,以经不同方式处理的 NK-92 细胞为效应细胞,效靶比为5:1,共同培养 2 h,采用流式细胞术检测 NK-92 细胞对 K562 细胞的杀伤率。NK-92 细胞处理方式为单纯重组蛋白处理(分别加入终浓度为 0、10、20 μg/ml 的重组蛋白培养 30 min)和表面受体封闭 + 重组蛋白处理(分别加入抗 ILT2、抗 KIR2DL4、抗 LT2 + 抗 KIR2DL4 抗体培养 30 min,再分别加入终浓度为 0、10、20 μg/ml 的重组蛋白培养 30 min)。 结果 ①蛋白质印迹分析表明所获重组蛋白为带有组氨酸标签的特异蛋白。②NK-92 细胞与 20 μg/ml 重组蛋白共培养 30 min 后,sHLA-G1 表达阳性率明显高于而 ILT2、KIR2DL4 受体表达阳性率均明显低于对照组(均 P < 0.05)。③以终浓度 0、10、20 μg/ml 的重组蛋白处理的 NK-92 细胞对 K562 细胞的杀伤率分别为 39.79% ± 2.00%、27.79% ± 0.75%、21.36% ± 0.67%(两两比较,均 P < 0.01);单独封闭 ILT2 受体,杀伤率分别为 23.09% ± 1.63%、21.13% ± 0.38%、18.42% ± 0.47%(两两比较,均 P < 0.01);单独封闭 KIR2DL4 受体,杀伤率分别为 30.74% ± 0.44%、26.03% ± 0.38%、21.15% ± 0.35%(两两比较,均 P < 0.01)。 结论 sHLA-G1 通过与 NK-92 细胞表面 ILT2 和 KIR2DL4 受体直接结合而抑制 NK-92 细胞的杀伤活性。 相似文献
132.
García-Samaniego J Soriano V Miró JM Romero JD Bruguera M Castilla J Esteban JI Gonźlez J Lissen E Moreno A Moreno S Moreno-Otero R Ortega E Quereda C Rodríguez M Sánchez-Tapias JM;Spanish Hepatitis-HIV Consensus Panel 《HIV clinical trials》2002,3(2):99-114
Co-infection by human immunodeficiency virus and hepatitis B and C viruses is quite common because they share similar routes of transmission. The introduction of highly active antiretroviral therapy has significantly improved the life expectancy of HIV-infected patients in the last few years. However, chronic viral hepatitis represents an emerging cause of morbidity and mortality in this population, either as a result of end-stage liver disease or as a consequence of hepatotoxicity induced by antiretroviral drugs. The main goal of the Consensus Conference was to establish specific recommendations for the management of chronic viral hepatitis B and C in HIV-infected patients. The role of orthotopic liver transplantation for co-infected individuals with end-stage liver disease was also assessed. 相似文献
133.
Development of a blocking enzyme-linked immunosorbent assay for the detection of avian polyomavirus-specific antibodies 总被引:5,自引:0,他引:5
Khan MS Johne R Beck I Pawlita M Kaleta EF Müller H 《Journal of virological methods》2000,89(1-2):39-48
Avian polyomavirus, described originally as budgerigar fledgling disease virus, has been associated with devastating contagious disease outbreaks in budgerigar aviaries. At present, this virus affects a wide range of psittacine and non-psittacine birds worldwide, and the serum neutralisation test is used for the serodiagnosis of avian polyomavirus infections. A blocking enzyme-linked immunosorbent assay was developed for the screening of large numbers of sera collected from various avian species. The assay employs a monoclonal antibody directed against the major structural protein VP1 as a blocking antibody in a sandwich blocking procedure. Either purified avian polyomavirus particles or avian polyomavirus VP1 expressed in recombinant baculovirus-infected Sf9 cells were used as antigen. The specificity of the blocking enzyme-linked immunosorbent assay was evaluated by testing sera directed against mammalian polyomaviruses. Using sera obtained from chicken infected experimentally with avian polyomavirus and a collection of psittacine field-origin sera, a good correlation was observed between the results of the blocking enzyme-linked immunosorbent assay and the serum neutralisation test. However, the blocking enzyme-linked immunosorbent assay is more rapid and more economic. Both, avian polyomavirus particles and VP1 produced by recombinant DNA technology proved to be suitable antigens. 相似文献
134.
The variations in anatomical structure and position of both carotid bodies were noted in 100 consecutive subjects who came to necropsy. Considerable variations in form were found. Although most carotid bodies (83% on the right and 86% on the left) were of the classic ovoid type, an appreciable minority was bilobed (9% on the right and 7% on the left) or double (7% on the right and 6% on the left); 1% were leaf shaped. All these anatomical variants have to be distinguished from the pathologically enlarged carotid body that may have a smooth or finely nodular surface. Anatomical variants (such as the bilobed) may themselves enlarge as a consequence of carotid body hyperplasia. 相似文献
135.
Abdulrahman Al-Dowaisan Nasser Fakim M Riaz Khan Nermina Arifhodzic Radakrishnan Panicker Abdulatif Hanoon Irfan Khan 《Annals of allergy, asthma & immunology》2004,92(2):262-267
BACKGROUND: Respiratory allergies are common in Kuwait, and the role of certain allergens has been previously documented. OBJECTIVE: To evaluate the results of skin prick tests to a range of allergens that were considered relevant to the vegetation surveys and aerobiological studies performed in Kuwait. METHOD: New patients attending our center during August 2002 to February 2003 with asthma or allergic rhinitis underwent skin prick tests to a battery of allergens. RESULTS: A total of 451 patients aged 5 to 60 years (mean age, 29.5 years) were tested. Of these patients, 403 (89.4%) had a positive test result to at least one allergen and were considered allergic. A total of 76.7% of the allergic patients had a positive reaction to Salsola pollen, with a mean wheal diameter of 8.25 mm (median, 8 mm). Chenopodium album was positive in 57.6% and Bermuda grass was positive in 38.2% of the allergic cases. Indoor allergens seemed to play a lesser role than pollens: Dermatophagoides pteronyssinus was positive in only 37.5%, and American and German cockroaches were positive in 33.2% and 22.3%, respectively. All the allergens other than Salsola elicited a mean wheal diameter of less than 6.25 mm (median, < or = 6 mm). CONCLUSIONS: Indoor allergens seem to play a lesser role in respiratory allergies in Kuwait. Most allergic patients become sensitized to pollens; the strongest and most frequent reaction is from Salsola pollen. Salsola imbricata is found growing extensively in most areas of the country, flowering mainly in autumn, when the most common pollen is of the Chenopod-Amaranth type and when most patients with seasonal allergic rhinitis become symptomatic. 相似文献
136.
Schijman A Colina R Mukomolov S Kalinina O García L Broor S Bhupatiraju AV Karayiannis P Khan B Mogdasy C Cristina J 《Clinical and diagnostic laboratory immunology》2004,11(2):433-435
Hepatitis C virus genotyping was assessed for 257 chronic hepatitis C patients with viral loads above 1,000 IU/ml. Twelve patients were coinfected with more than one genotype. Their median viral loads did not differ significantly from those observed for monoinfected patients, which in turn did not vary significantly among different genotypes. 相似文献
137.
Zusammenfassung Es wird über einen Fall akuter Erythroleukämie mit G-Trisomie berichtet und die mögliche Bedeutung hereditärer Faktoren für die Manifestation akuter Leukämien diskutiert.
Summary The cytogenetic analyses of direct bone marrow preparations in a 53 years old male with acute erythroleukaemia of 9 months disease history, revealed persistently a G-trisomy in a dominant cell line with 47 chromosomes. The peripheral blood culture preparations with phytohaemagglutinin exhibited normal diploid cell line.The frequent occurrence of akute leukaemia in Down's syndrome tempts to implicate that leukaemia with G-Trisomy having no signs of Down's syndrome is a somatic mutation initiated by some unknown hereditary recessive genes mechanisms.相似文献
138.
Janine Reichenbach Andrea Jarisch Saima Khan Miriam H?mberg Christina Bez Stefan Zielen 《Annals of allergy, asthma & immunology》2002,89(5):498-502
BACKGROUND: High levels of serum eosinophil cationic protein (sECP) as a marker of eosinophilic airway inflammation have been described as a predictor of childhood asthma. Bronchial hyperreactivity (BHR) appears to be secondary to the release of inflammatory mediators. OBJECTIVE: We investigated the possible correlation between eosinophilic inflammation and BHR in 72 infants with recurrent wheezing. METHODS: To determine bronchial reactivity, lung function measurements with methacholine challenge were performed in 72 infants, aged 12 to 30 months, and the degree of BHR to methacholine was compared with sECP values. Patients were grouped according to low (group 1, <10 microg/L, n = 22), medium (group 2, 10 to 20 microg/L, n = 23), and high (group 3, >20 microg/L, n = 27) sECP values. RESULTS: In group 1, sECP levels ranged from 3.1 to 9.9 microg/L, mean 6.6 microg/L +/- standard deviation [SD] 2.3, in group 2, from 10.3 to 19.8 microg/L, mean 14.3 microg/L +/- SD 2.8, and in group 3 from 23.0 to 66.7 microg/L, mean 34.5 microg/L +/- SD 9.5. Distribution of provocative methacholine concentration among groups was as follows: group 1, 30 to 976 microg, mean 350.9 microg +/- SD 258.3; group 2, 36 to 752 microg, mean 340.7 microg +/- SD 226.3; group 3, 41 to 848 microg, mean 301.3 microg +/- SD 189.8 methacholine. CONCLUSION: There was no significant correlation between sECP levels and bronchial reactivity in all groups (r = -0.076, P = 0.6), indicating that these parameters reflect two independent pathogenic mechanisms in the etiology of childhood asthma. 相似文献
139.
Bagher Larijani Mir Reza Bekheirnia Akbar Soltani Alireza Khalili‐Far Hossein Adibi Reza Baradar Jalili 《American journal of human biology》2004,16(2):168-171
The aim of this study was to determine the relationships between bone mineral density (BMD) and blood pressure in 214 men, age 20–76. BMD measurements were done by dual X‐ray absorptiometry using a Lunar DPXMD densitometer at the lumbar spine (L2–L4) and different femoral regions. Systolic (SBP) and diastolic (DBP) blood pressure were measured using an MPC‐350 sphygmomanometer. Physicians gathered demographic data and participants' dietary intake of calcium were determined by using food frequency questionnaires. After adjusting for age, body mass index, dietary calcium, and exercise history, multiple linear regression models showed that DBP was negatively related to femoral neck BMD (β = ?0.145, P = 0.032) and just shy of significant association with femoral neck BMC (β = ?0.114, P = 0.079). SBP was correlated with femoral neck (r = ?0.171, P = 0.012) and Ward's (r = ?0.186, P = 0.006) BMD but not after adjusting for possible confounders. Further studies are needed to determine whether elevated blood pressure is causally related to the development of low bone mass. Am. J. Hum. Biol. 16:168–171, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
140.