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1.
目的:观察整合素β1在自身免疫性心肌炎小鼠心肌的表达变化。方法:猪肌凝蛋白皮下注射免疫Balb/c小鼠,建立慢性自身免疫性心肌炎模型,于初次免疫后14、30和60d对心肌组织进行病理学检查,同时用激光共聚焦技术和间接免疫荧光法检测整合素β1在心肌的表达变化。结果:在初次免疫后14d,小鼠心脏有局部炎症出现,整合素β1在心脏血管周围的表达高于正常组(P<0.05);在第30天,小鼠心脏炎性浸润更加明显,整合素β1在心肌的表达增强,显著高于正常组(P<0.05);第60天,小鼠心脏炎症细胞减少,而纤维化则开始出现,整合素β1在心肌的表达最强(P<0.05),且排列紊乱。结论:整合素β1在自身免疫性心肌炎的发生及发展过程中起着不同重要作用,整合素β可能参与自身免疫反应及心肌的重构。 相似文献
2.
目的:介绍实验性小鼠膜性肾小球肾炎(MGN)的复制方法,并探讨其免疫荧光定量分析在肾小球肾炎研究中的应用价值。方法:制备阳离子化牛血清白蛋白(GBSA)并复制小鼠MGN,对各组小鼠进行电镜及免疫荧光观察,并进行免疫荧光定量研究。结果:电镜、免疫荧光观察均显示病理Ⅰ组(PⅡ组)具有典型的MGN病变,病理Ⅱ组(PⅡ组)病变轻微且不典型。免疫荧光定量研究证实PⅠ、PⅡ组与对照组差异有显著性;PⅠ、PⅡ组间差异无显著性。结论:C—BSA可作为复制小鼠MGN的良好抗原,隔日2mg/只尾静脉注射4w即可复制出稳定的小鼠MGN模型。免疫荧光定量分析不仅能直接而准确地反映MGN病理变化,而且在MGN早期即具有诊断价值。 相似文献
3.
Identification of Babesia bigemina infected erythrocyte surface antigens containing epitopes conserved among strains 总被引:4,自引:0,他引:4
SANKALE SHOMPOLE TERRY F. McELWAIN DOUGLAS P. JASMER STEPHEN A. HINES JOSEPH KATENDE ANTHONY J. MUSOKE FRED R. RURANGIRWA TRAVIS C. McGUIRE 《Parasite immunology》1994,16(3):119-127
The presence of previously uncharacterized antigens (new antigens) on the surface of intact erythrocytes infected with three strains of Babesia bigemina from Kenya and one each from Puerto Rico, Mexico, St. Croix, and Texcoco-Mexico was demonstrated by indirect immunofluorescent antibody (IFA) reactions. These antigens were not strain specific because antibodies in bovine immune serum to either the Mexico or Kenya isolates reacted with all seven strains tested. Homologous and heterologous immune serum antibodies bound a maximum of 83% and 55%, respectively, of intact erythrocytes infected with the Kenya-Ngong strain but not uninfected erythrocytes. Both sera caused agglutination of only infected erythrocytes. Antibodies eluted from the surface of glutaraldehyde (0.25%) fixed infected erythrocytes had IFA reaction patterns among strains similar to those of immune sera before elation. Eluted antibodies were used to determine if these antigens were protein and encoded by B. bigemina. Eluted antibodies bound seven parasite-encoded proteins of 240, 220, 66, 62, 58, 52 and 38 kDa in an erythrocyte surfacespecific immunoprecipitation reaction of 35-methionine labelled proteins. It was concluded that the surface of B. bigemina infected erythrocytes had parasite-encoded proteins and that these proteins had surface exposed epitopes that were conserved among the seven strains examined which were from two continents. 相似文献
4.
The protective effect of affinity purified antigen has been investigated in an experimental model for malaria which shows a well marked recrudescence of parasitaemia, a feature of the disease in man. A monoclonal antibody (MoAb) recognizing an epitope common to two genetically distinct cloned lines of Plasmodium chabaudi (AS and CB), was used to purify a Mr250,000 polymorphic schizont antigen (PSA) from these parasites. The purified preparations were then examined for the presence of specific and cross-reactive epitopes by immunoprecipitation with a panel of MoAb raised against P. chabaudi AS. When tested previously on smears of parasitized blood by immunofluorescence, or against lysates of parasitized erythrocytes by immunoprecipitation, most of these MoAb had been found to be AS specific. When either AS or CB affinity purified Mr250,000 PSA was used as the target, these same MoAb immunoprecipitated both antigens, and in some cases, a number of associated polypeptides (AP) which copurify with the Mr250,000 PSA. Subsequently, mice were immunized with either the purified AS or CB antigens in Freund's complete adjuvant (FCA). Prechallenge sera were compared by indirect immunofluorescence and immunoprecipitation. Sera from mice immunized with AS antigen reacted strongly with AS and cross-reacted with CB parasite preparations. Pre-challenge serum from CB antigen immunized mice reacted well with CB, but only faintly with AS preparations. In mice immunized with the AS antigen and then challenged with either AS or CB parasites, the initial parasitaemias were delayed in appearance and the height of the peak parasitaemia reduced, an effect which was most pronounced after challenge with homologous parasites. Only homologous challenge of the mice immunized with CB antigen produced statistically significant modification of the initial parasitaemia. In the immunized mice challenged with homologous parasites, the delayed appearance and slightly reduced peak of the primary parasitaemia was associated with delayed resolution of the patent parasitaemia and significant enhancement of the recrudescence. 相似文献
5.
Jin Hui-ming 《华中科技大学学报(医学英德文版)》1990,10(4):193-200
Summary The content of plasma fibronectin and tissue extractable fibronectin in normal rats was measured with rocket immunoelectrophoresis
and ELISA in the present study. The difference in tissue fibronectin distribution in various organs and the correlation between
distribution and content of fibronectin have been studied. We suggest that tissue fibronectin may be a complex component.
The change in plasma fibronectin reflects a dynamic balance existing between the tissue fibronectin pool and plasma fibronectin
pool in normal rats. Plasma fibronectin and tissue fibronectin concentrations are not static, and they can only be maintained
in a relatively stable state in normal rats. 相似文献
6.
Summary. A prevalence study of Ureaplasma urealyticum (UU) infection of the male genital tract was carried out in Shanghai between March 1992 and June 1995. Significantly higher frequency of UU infection was found among infertile males (549/1416) as compared to fertile controls (34/375). Examination of 8 specimens each from infertile men and fertile subjects by electron microscopy, immunogold and immunofluorescence techniques, demonstrated adhesion of Ureaplasma urealyticum to the membrane of spermatozoa and exfoliated germ cells. In addition, gold particles on Ureaplasma urealyticum were found to be adhered to the sperm surface in 4 of the 8 samples. Strong specific anti-UU fluorescence was detected in 6 of 8 samples, mainly on the midpieces and post-acrosomal regions of the spermatozoa.
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
7.
目的:检测各种肾小球疾病患者血清中抗中性粒细胞胞浆抗体(ANCA)并探讨其临床意义。方法:应用间接免疫荧光法(IIF)检测20例正常人及131例各种肾小球疾病患者血清中ANCA。结果:131例患者中有11例ANCA阳性性(阳性率为8.4%),且均为P-ANCA阳性,而20例正常对照组无1例阳性(P<0.05)。ANCA阳性中以新月体性肾炎、狼疮性肾炎、紫癜性肾炎的阳性率较高,分别为67%、25%、16.7%。新月体性肾炎与IgA肾病等原发性肾小球疾病组比较有显著性差异(P<0.05)。结论:ANCA在各种肾小球疾病中并不少见,尤其是新月体性肾炎、狼疮性肾炎、紫癜性肾炎的阳性率较高,推测ANCA可能在这些疾病的发病机理中起了一定的作用。 相似文献
8.
N. V. Piven' V. I. Khichenko M. B. Shtark 《Bulletin of experimental biology and medicine》1979,88(3):1004-1007
The existence of cross protein antigens common to several species of invertebrates and vertebrates on the membrane of neurons and glial cells of Helix pomatia was demonstrated in vitro by Coons' immunofluorescence method. The presence of nerve-specific protein S-100 on the membrane of these cells was established. The antigenic heterogeneity of membranes of a population of neurons also was observed. Differences were found in the concentrations of antigens on the somatic and axon membranes. The character of distribution of specific fluorescence indicates possible qualitative and (or) quantitative differences in the content of nervespecific proteins in different areas of the neuron membrane.Laboratory of Central Mechanisms of Regulation and Control, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR, Novosibirsk. (Presented by Academician of the Academy of Medical Sciences of the USSR V. P. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 299–301, September, 1979. 相似文献
9.
10.
Monoclonal antibodies against human granulocytes and myeloid differentiation antigens 总被引:4,自引:0,他引:4
Patrice Mannoni Anna Janowska-Wieczorek A. Robert Turner Locksley McGann Jean-Michael Turc 《Human immunology》1982,5(4):309-323
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis. 相似文献