共查询到18条相似文献,搜索用时 125 毫秒
1.
2.
3.
通常人们常说的血型,是根据血液中红细胞表面抗原的不同而划分的。输血时经常提到ABO血型系统,它是根据红细胞表面特异性抗原的不同将血型分为A、B、O和AB型,红细胞表面的抗原和它的抗体一旦结合,就会发生溶血(红细胞破裂,血红蛋白溢出)反应,所以输血一定要注意血型相配。 相似文献
4.
[例题]甲、乙、丙、丁四人同行,甲因车祸需要输血。医生用B型标准血清检验四人血液,只有甲、乙的红细胞发生了凝集反应。通过检验,只有丁能为甲输血。那么乙的血型应是…………………………………………( ) 供选答案:A.O型 B.A型 C.AB型D.B型 相似文献
5.
我们通常所说的血型是指红细胞表面的抗原差异(如ABO血型系统、Rh血型系统等),其实这只是狭义的理解。从广义的角度来说,血型除了红细胞表面的抗原差异外,还包括白细胞(如HLA系统)、血小板、血浆等成分的抗原差异。据统计,人体所有的血型组合起来可达1.110287×10~(19)之多。 ABO血型系统是诸多血型系统中的一种,血型作为一种遗传标记,在法医学广泛应用于鉴定亲子关系。ABO血型受Ⅰ~A、Ⅰ~B、ⅰ三个复等位基因控制的,其中ⅰ为隐性基因。通常分为六种基因型:Ⅰ~AⅠ~A、Ⅰ~Aⅰ、Ⅰ~BⅠ~B、Ⅰ~Bⅰ、Ⅰ~AⅠ~B、ⅱ;四种表型:A、B、AB、O四种血型。A型人含有A血型物 相似文献
6.
7.
用于B→O血型改造的不同α-半乳糖苷酶的比较 总被引:1,自引:0,他引:1
α 半乳糖苷酶因可水解人B型红细胞表面的α 半乳糖残基 ,使B抗原结构变成O抗原结构 ,而成为B→O血型改造的工具酶 .对可能具有酶解B抗原活性的 3种α 半乳糖苷酶 ,即来源于大豆、咖啡豆和人的α 半乳糖苷酶的结构和功能进行了比较研究 .首先 ,利用序列分析工具对 3种酶蛋白的一级结构和特性进行了比较 ;随后 ,将编码大豆和人的α 半乳糖苷酶的cDNA克隆入毕赤酵母中进行表达 ,对筛选所得表达菌株进行诱导培养 ,并从培养上清中纯化重组的大豆和人α 半乳糖苷酶 ;分别测定大豆、咖啡豆和人α 半乳糖苷酶的生物化学性质以及它们的底物特异性 ;最后 ,以纯化的重组酶对人B型红细胞进行酶解 ,并测定酶解后红细胞的结构与功能 .结果表明 ,人源的α 半乳糖苷酶不适于酶解B抗原 ,而大豆来源的α 半乳糖苷酶不仅可作为B→O血型改造的工具酶 ,而且比咖啡豆来源的α 半乳糖苷酶更具优势 相似文献
8.
9.
10.
ABO血型的发现(K.Landsteiner,1900)与孟德尔定律重被发现(deVries,Correns,VonTschermak)同年,临床输血配型沿用至今。但对它的研究一直持续到分子生物学时代,可谓是既古老又现代的课题。1ABO血型的分型及其免疫学特征众所周知,ABO血型的分型是根据血液凝集试验确定的。不同型别血液的凝集现象是免疫反应,是细胞表面抗原与异型血清中抗体结合的结果。用以表征其型别的A、B和C(1902年根据LudwikHirszfeld的建议改记作O)源于凝血团的类型编号。红细胞表面具有抗原A的血液称为A型;抗原为B者称作B型;同时具有抗原A… 相似文献
11.
Bradley AJ Scott MD 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2004,807(1):163-168
Alloimmunization to donor blood group antigens remains a significant problem in transfusion medicine. To attenuate the risk of alloimmunization, we have pioneered the membrane grafting of methoxypoly(ethylene glycol) (mPEG) to produce immunocamouflaged red blood cells (RBC). Grafting of the mPEG was accomplished using cyanuric chloride activated mPEG (CmPEG; M(r) = 5000), benzotriazole carbonate methoxyPEG (BTCmPEG; M(r) = 2000, 5000 or 20000); or N-hydroxysuccinimidyl ester of mPEG propionic acid (SPAmPEG; M(r) = 5000, or 20000). Because of the heterogeneity of grafting, a crucial tool in developing the stealth RBC is an ability to purify the modified RBC from unmodified (immunogenic) donor cells. As demonstrated, a (5, 4) dextran:PEG aqueous two-phase polymer partitioning system cleanly separated the immunologically silent mPEG-grafted human RBC from control or lightly modified cells. Cell mixing experiments employing varying ratios of mPEG-modified and control RBC confirmed the purification efficacy of the phase partitioning system. Proportional changes in PEG-rich phase partitioning were achieved by increasing either the quantity of surface mPEG or the mPEG molecular weight. The biological viability of purified mPEG-RBC (BTCmPEG; [M(r) = 20000) was demonstrated by their normal in vivo survival at immunoprotective grafting concentrations (相似文献
12.
Immunocamouflaged red blood cells (RBC) are produced by cell surface derivatization with methoxypolyethylene glycol (mPEG). These immunologically attenuated cells may reduce the risk of allosensitization in chronically transfused patients. To characterize the effects of differing linker chemistries and polymer lengths, RBC were modified with cyanuric chloride activated mPEG (C-mPEG 5 kDa), benzotriazole carbonate methoxyPEG (BTC-mPEG; 5 or 20 kDa) or N-hydroxysuccinimidyl ester of mPEG propionic acid (SPA-mPEG; 2, 5 or 20 kDa). Biophysical methods including particle electrophoresis and aqueous two-phase polymer partitioning were employed to compare the PEG derivatives. While C-mPEG was faster reacting, both BTC-mPEG and SPA-mPEG gave comparable findings after 1 h. Both PEG surface density and molecular mass had a large effect on RBC surface properties. Proportional changes in electrophoretic mobility and preferential phase partitioning were achieved by increasing either the quantity of surface PEG or the PEG molecular mass. In addition, two-phase partitioning may provide a means for efficiently removing unmodified or lightly modified (hence potentially immunogenic) RBC in the clinical setting. Furthermore, mPEG modification significantly inhibits cell-cell interaction as evidenced by loss of Rouleaux formation and, consequently, sedimentation rate. Importantly, BTC-mPEG 20 kDa RBC showed normal in vivo survival in mice at immunoprotective concentrations (up to 2 mM). 相似文献
13.
Biophysical consequences of linker chemistry and polymer size on stealth erythrocytes: size does matter 总被引:5,自引:0,他引:5
Immunocamouflaged red blood cells (RBC) are produced by cell surface derivatization with methoxypolyethylene glycol (mPEG). These immunologically attenuated cells may reduce the risk of allosensitization in chronically transfused patients. To characterize the effects of differing linker chemistries and polymer lengths, RBC were modified with cyanuric chloride activated mPEG (C-mPEG 5 kDa), benzotriazole carbonate methoxyPEG (BTC-mPEG; 5 or 20 kDa) or N-hydroxysuccinimidyl ester of mPEG propionic acid (SPA-mPEG; 2, 5 or 20 kDa). Biophysical methods including particle electrophoresis and aqueous two-phase polymer partitioning were employed to compare the PEG derivatives. While C-mPEG was faster reacting, both BTC-mPEG and SPA-mPEG gave comparable findings after 1 h. Both PEG surface density and molecular mass had a large effect on RBC surface properties. Proportional changes in electrophoretic mobility and preferential phase partitioning were achieved by increasing either the quantity of surface PEG or the PEG molecular mass. In addition, two-phase partitioning may provide a means for efficiently removing unmodified or lightly modified (hence potentially immunogenic) RBC in the clinical setting. Furthermore, mPEG modification significantly inhibits cell-cell interaction as evidenced by loss of Rouleaux formation and, consequently, sedimentation rate. Importantly, BTC-mPEG 20 kDa RBC showed normal in vivo survival in mice at immunoprotective concentrations (up to 2 mM). 相似文献
14.
15.
Xiaofei Li YuShiang Lin Tingting Liu Ye Zhang Guangyan Zhuang Tianhong Miao Zhiyuan Xu 《Asia-Pacific Journal of Blood Types and Genes》2018,2(4):263-268
The serological examination, blood transfusion strategies and the molecular analysis to blood group chimera were conducted to demonstrate existent of chimera in blood group. The blood grouping of ABO or/and RhD, newborn red blood cells separated by capillary centrifugation. Aabsorption tests and DTT treated agglutination erythrocyte tests were implemented in four patients. Further molecular biological research was conducted on one patient''s sample. The results showed that for patient 1: ABO blood group was AB/B chimera, Rh blood cells contained the RhCE chimera gene; Patient 2: Rh blood cells contained the RhD chimera gene; Patient 3: ABO blood group was AB/B chimera, Rh blood cells contained the RhD chimera gene; Patient 4: ABO blood group was O/B chimera, Rh blood cells contained the RhCE chimera gene. The study suggests that the individuals categorized as chimeras are likely to be more common than existing literature reports. According to the serological tests, in the absence of a history of recent blood transfusion or disease to cause reduced antigen, the phenomena of hybrid aggregation of the ABO and Rh blood system were the main feature. In terms of transfusion strategy, the selection of ABO and Rh blood groups should be depended on the group of cells with more antigens. 相似文献
16.
Evasion of Immunity to Plasmodium falciparum: Rosettes of Blood Group A Impair Recognition of PfEMP1
The ABO blood group antigens are expressed on erythrocytes but also on endothelial cells, platelets and serum proteins. Notably, the ABO blood group of a malaria patient determines the development of the disease given that blood group O reduces the probability to succumb in severe malaria, compared to individuals of groups A, B or AB. P. falciparum rosetting and sequestration are mediated by PfEMP1, RIFIN and STEVOR, expressed at the surface of the parasitized red blood cell (pRBC). Antibodies to these antigens consequently modify the course of a malaria infection by preventing sequestration and promoting phagocytosis of pRBC. Here we have studied rosetting P. falciparum and present evidence of an immune evasion mechanism not previously recognized. We find the accessibility of antibodies to PfEMP1 at the surface of the pRBC to be reduced when P. falciparum forms rosettes in blood group A RBC, as compared to group O RBC. The pRBC surrounds itself with tightly bound normal RBC that makes PfEMP1 inaccessible to antibodies and clearance by the immune system. Accordingly, pRBC of in vitro cloned P. falciparum devoid of ABO blood group dependent rosetting were equally well detected by anti-PfEMP1 antibodies, independent of the blood group utilized for their propagation. The pathogenic mechanisms underlying the severe forms of malaria may in patients of blood group A depend on the ability of the parasite to mask PfEMP1 from antibody recognition, in so doing evading immune clearance. 相似文献
17.
Avraham Schlager Gideon Zamir Gregory Barshtein Saul Yedgar Dan Arbell 《Cell biochemistry and biophysics》2010,58(3):157-161
Erythrocyte adhesion to the vascular endothelium is one of the key determinants of microcirculatory blood flow. Adhesion is
a complex process determined by the intricate interaction among red blood cells (RBC), plasma factors, and the vascular endothelium.
Rats are commonly used as disease models to investigate the pathophysiology of various hematological disease processes occurring
in humans and their response to prospective treatments. The aim of our study was to characterize the adhesion of RBC in adult
blood from rat and human subjects, in order to test the validity of rat models for adhesion-related disease processes. We
demonstrated that adhesion of RBC from rats (rRBC), to endothelial cells (EC) in plasma-free buffer, is stronger than from
human subjects (hRBC). In addition, plasma proteins induced elevation of hRBC (eightfold) but depression of rRBC (threefold)
adhesion to EC. It is thus suggested to be aware of the difference in RBC/EC interaction for human and rat subjects, when
studying models of blood flow. 相似文献
18.
Transgenic mouse models of hemoglobinopathies unravel pathophysiological mechanisms; yet the validity of the red blood cell (RBC) model of human hemoglobin (hHb) enveloped by a mouse (m) membrane has been questioned. Isoelectric focusing of hHb and mHb from transgenic mRBC shows a greater association of mHb to the mouse membrane compared to normal hHbA, supporting a species-specific Hb-mRBC membrane interaction. Enhanced hmutant Hb (HbE, HbS and HbC)-mRBC membrane affinities correlates with enhanced membrane lipid peroxidation and parallel those reported in hRBC, lending support to transgenic mRBC as models of hemoglobinopathies. Species-specific Hb-membrane interaction may be overridden by Hb charge and conformational alterations. 相似文献