Frequency analysis of B lymphocytes specific for Rh antigens in naturally immunized Rh-negative women

BACKGROUND AND OBJECTIVES: Despite a successful outcome of the anti-D prophylaxis programme, alloimmunization still occurs. The aim of this study was to estimate the frequency of Rh-specific B lymphocytes in the peripheral blood of nine Rh-alloimmunized individuals at different time intervals after parturition. MATERIALS AND METHODS: The donors' B lymphocytes were transformed with Epstein-Barr virus (EBV) and cultured at different cell densities over a feeder of human fetal fibroblasts. Culture supernatants were screened for human immunoglobulin by enzyme-linked immunosorbent assay (ELISA) and for anti-Rh antibody by using a direct haemagglutination technique. The percentage of CD19+ B lymphocytes in peripheral blood was determined by flow cytometry, and the frequency of Rh-specific B lymphocytes was estimated by limiting-dilution assay (LDA). RESULTS: The frequency of Rh-specific B lymphocytes varied from 1 : 150 to 1 : 27,850 in different donors. There was a decrease in this frequency and level of anti-Rh antibody with increase in time interval between bleeding and last exposure to the antigen. Furthermore, a positive correlation was observed between the titre of Rh-specific antibody and frequency of Rh-specific B cells in each of three subjects bled at multiple time-points postdelivery. CONCLUSIONS: The magnitude of the specific antibody response to Rh antigens varies greatly in Rh-alloimmunized women, which partly reflects the difference in frequency of specific B cells in these individuals.     

人参皂苷对过氧化氢诱导的HepG2细胞损伤的保护作用

目的：探讨人参皂苷对过氧化氢（H₂O₂）诱导的HepG2细胞氧化应激损伤的保护作用,并阐明其作用机制。方法：体外培养HepG2细胞,采用不同浓度（0.1、0.2、0.3、0.4、0.5、0.6、0.7、0.8和1.0 mmol·L^-1）H₂O₂诱导HepG2细胞损伤。将HepG2细胞分为空白组、对照组、损伤组、人参皂苷对照组和人参皂苷保护组。10、20和40μmol·L^-1人参皂苷RH1、F1、RD、RO和RE分别孵育细胞3 h,H₂O₂损伤2 h,采用细胞增殖与毒性检测试剂盒（CCK-8）检测细胞存活率,CAA法检测细胞抗氧化活性,2',7'-二氯荧光黄双乙酸盐（DCFH-DA）荧光探针法检测细胞中活性氧（ROS）水平,WST-1法检测细胞中超氧化物歧化酶（SOD）活性。结果：H₂O₂半数抑制浓度（IC₅₀）为0.4 mmol·L^-1。与损伤组比较,10、20和40μmol·L^-1人参皂苷RH1、F1、RD、RO和RE预处理后,H₂O₂诱导氧化损伤的HepG2细胞存活率均有不同程度的升高,其中人参皂苷F1保护组细胞存活率升高最明显（P<0.05）。与对照组比较,10、20和40μmol·L^-1人参皂苷RH1、F1、RD、RO和RE保护组HepG2细胞存活率差异无统计学意义（P>0.05）。人参皂苷F1的半数效应浓度（EC₅₀）为（15.82±0.82）μmol·L^-1,CAA当量为（1 275.20±33.90）μmol TE/100 μmol·L^-1人参皂苷F1。与对照组比较,损伤组细胞中ROS水平明显升高（P<0.05）,SOD活性明显降低（P<0.05）;与损伤组比较,人参皂苷F1保护组细胞中ROS水平明显降低（P<0.05）,SOD活性明显升高（P<0.05）。结论：人参皂苷F1通过提高细胞抗氧化能力,降低细胞中ROS水平,提高细胞SOD活性对H₂O₂诱导的HepG2细胞氧化应激损伤起到保护作用。     

Analysis of density and epitopes of D antigen on the surface of erythrocytes from DEL phenotypic individuals carrying the RHD1227A allele

Background

The characteristics of the D antigen are important as they influence the immunogenicity of D variant cells. Several studies on antigenic sites have been reported in normal D positive, weak D and partial D cases, including a comprehensive analysis of DEL types in Caucasians. The aim of this study was to assess D antigen density and epitopes on the erythrocyte surface of Asian type DEL phenotypic individuals carrying the RHD1227A allele in the Chinese population.

Materials and methods

A total of 154 DEL phenotypic individuals carrying the RHD1227A allele were identified through adsorption and elution tests and polymerase chain reaction analysis with sequence-specific primers in the Chinese population. D antigen density on the erythrocyte surface of these individuals was detected using a flow cytometric method. An erythrocyte sample with known D antigen density was used as a standard. Blood samples from D-negative and D-positive individuals were used as controls. In addition, D antigen epitopes on the erythrocyte surface of DEL individuals carrying the RHD1227A allele were investigated with 18 monoclonal anti-D antibodies specific for different D antigen epitopes.

Results

The means of the median fluorescence intensity of D antigen on the erythrocyte membrane surface of D-negative, D-positive and DEL individuals were 2.14±0.25, 193.61±11.43 and 2.45±0.82, respectively. The DEL samples were estimated to have approximately 22 D antigens per cell. The samples from all 154 DEL individuals reacted positively with 18 monoclonal anti-D antibodies specific for different D antigen epitopes.

Discussion

In this study, D antigen density on the erythrocyte surface of DEL individuals carrying the RHD1227A allele was extremely low, there being only very few antigenic molecules per cell, but the D antigen epitopes were grossly complete.     

A comprehensive investigation of RHD polymorphisms in the Chinese Han population in Xi’an

Background

This study is a comprehensive analysis of RHD in D-negative phenotypes in saline, in Xi’an, Shanxi province, central China.

Material and methods

DCcEe in saline was measured for each blood sample from every donor between January 2008 and June 2012 in the Xi’an Blood Centre, China. D-negative results were confirmed by an indirect antiglobulin test and further investigated by adsorption-elution as required. The initial step of molecular analysis was RHD zygosity testing. Then RHD was detected by a sequence-specific polymerase chain reaction system for RHD(1227G>A), weak D type 15, and RHD(711delC) alleles for the samples carrying at least one RHD. For the remaining non-identified samples, ten RHD exons were amplified using a previously widely used RHD coding region sequencing method. Some RHD/RHCE conversion alleles were identified while those remaining were submitted to direct sequencing.

Results

Overall, 2,493 D-negative samples in saline were detected in a total of 890,403 donors (D-negative rate, 0.28%). Among the D-negative individuals, RHD deletion (d/d) was assessed in 1685 donors (67.59%). Non-functional RHD alleles were detected in 184 donors (7.38%), the most common being the RHD-CE(2–9)-RHD and RHD(711delC) alleles. Two new alleles were observed and family investigations were performed; RHD(1227G>A) DEL was detected in 516 individuals (20.70%), and weak D or partial D variants were identified in 108 donors (4.33%). The most common alleles were weak D type 15, D^VI type 3 and D^V type 2. Four new weak D alleles were noted, and two cases of RHD(1227G>A)/weak D type 15 heterozygosity were confirmed.

Conclusions

Currently, it seems to be difficult to observe any new RHD alleles in the Han Chinese population. D prediction in this population is easier because popular alleles are dominant, accounting for about 99.80% of alleles in D-negative people. Weak D types and partial D variants are rare and occur in approximately 0.01% of the population.     

探讨ABO、RhD血型调查与建立Rh表型库在安全输血中的临床意义

目的 调查河北省邯郸市峰峰矿区ABO、RhD血型在人群中的分布情况,分析患者不规则抗体筛查结果,探讨ABO、Rh血型调查与建立Rh表型库在安全输血中的临床意义。 方法 收集我院8 000例住院患者ABO血型及RhD血型的检测结果,对需输血的患者5 000例进行不规则抗体检测,阳性结果标本进一步行抗体特异性鉴定。随机选取3 000袋RhD阳性滤白红细胞悬液样本检测Rh表型,通过电脑建立献血者Rh表型数据库,探讨其在输血中的重要意义及价值。 结果 8 000例患者中ABO血型分布情况从多到少依次为B型血（32.02%）、O型血（28.98%）、A型血（27.01%）、AB型血（11.99%）。不同年龄组间ABO血型分布情况差异有统计学意义（P＜0.05）,不同性别组中ABO血型分布情况差异无统计学意义（P＞0.05）。8 000例患者中RhD阴性48例（0.60%）。男性和女性 Rh血型分布差异无统计学意义（P＞0.05）。5 000例需输血患者的血样标本中不规则抗体阳性者30例（0.60%）,Rh血型系统抗体阳性19例（63.33%）,抗-E检出率最高。不规则抗体的检出率女性显著高于男性,差异有统计学意义（P＜0.05）。3 000例RhD阳性献血者血样标本Rh血型表型共8种,其中CCDee检出率最多,其次为CcDEe,DcDEE和ccDee检出率较少。 结论 ABO血型的分布与地域及年龄有关;临床上除在患者输血前进行不规则抗体筛查,应进一步检测其抗体特异性;建立献血者Rh表型数据库有利于预防因Rh表型不符输血引起的溶血性输血反应,对于临床安全输血工作具有重大意义。     

注射用益气复脉(冻干)的质量标志物研究

注射用益气复脉(冻干)是由红参、麦冬和五味子3味药材精制而成,临床上主要用于治疗冠心病劳累型心绞痛气阴两虚证及冠心病所致慢性左心功能不全II、III级气阴两虚证。根据质量标志物概念,从物质基础、药效、网络药理、药动学及药性等方面对注射用益气复脉(冻干)质量标志物进行预测分析,初步确定人参皂苷Rb1、Rg1、Rf、Rh1、Rc、Rb2、Ro、Rg3及麦冬皂苷C、麦冬苷元-3-O-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖苷、偏诺皂苷元-3-O-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃木糖基-(1→4)-β-D-吡喃葡萄糖苷、果糖、五味子醇甲13个成分为质量标志物,并以此为核心建立全程质量控制体系。基于质量标志物对注射用益气复脉(冻干)进行质控方法研究,可以为中药注射剂质量评价提供新的研究思路。     

一测多评法测定竹节参中7种皂苷类成分的含量

目的建立一测多评法同时测定竹节参中7种皂苷类成分的含量,并验证此方法在竹节参中应用的可行性与适用性。方法采用HPLC法,以竹节参皂苷Ⅴ为内参物,建立人参皂苷Rg1、Re、Rb1,假人参皂苷RT1,竹节参皂苷Ⅳ、Ⅳa的相对校正因子(fs/i),并利用fs/i计算竹节参样品中成分的含量,同时用外标法测定各成分的含量,比较2种方法的差异。结果人参皂苷Rg1、Re、Rb1,假人参皂苷RT1,竹节参皂苷Ⅳ和Ⅳa的fs/i分别为1.286 7、1.432 7、0.966 6、0.962 4、1.207 2、0.938 4。采用一测多评法与外标法得到的10批竹节参样品各成分含量无显著性差异。结论建立的一测多评法准确性高,可用于竹节参皂苷类成分的定量分析和质量评价。     

生物黏附性三七总皂苷-白及多糖-海藻酸钠复合微球的制备及表征

目的利用白及多糖(BSP)的生物黏附性,与海藻酸钠(SA)混合作为复合载体,以具有缓释特性的三七总皂苷(PNS)分散体作为包封药物,制备具有生物黏附性的PNS-BSP-SA复合微球。方法采用离子交联法制备微球,通过单因素试验和正交设计考察并优化处方工艺。通过扫描电镜(SEM)、粒径分布、差示扫描量热法(DSC)分析、溶胀性能测定、体外黏附性能评价、体外释放研究对微球进行表征。结果 PNS-BSP-SA复合微球圆整度较好,表面粗糙不平有褶皱,粒径分布较窄,PNS原料药以无定形状态均匀分散于微球中。最佳处方工艺制备的微球工艺稳定,重现性较好,与直接加入PNS原料药制备的微球相比,PNS分散体微球的载药量、包封率和得率均明显增加,分别为10.34%、51.25%、82.21%,而PNS原料药微球的载药量、包封率、得率分别为4.04%、12.16%、61.35%。BSP的加入增加了SA微球的溶胀性能,明显增加了其在大鼠胃部的滞留率。PNS-BSP-SA复合微球中人参皂苷Rg1的释放较PNS原料药缓慢。结论 BSP增加了微球的生物黏附性,将PNS制备为分散体,提高了微球的载药量、包封率和得率,并使微球具有一定的缓释性能。     

基于UPLC结合比色法的葛桑降糖胶囊质量控制研究

目的构建葛桑降糖胶囊的质量控制方法。方法采用比色法测定葛桑降糖胶囊粗多糖、总皂苷和总黄酮含量;采用UPLC建立葛桑降糖胶囊的指纹图谱,测定了10个批次产品;并利用中药色谱指纹图谱相似度评价系统(2012版本)进行相似度评价,确定共有峰。结果 3批次葛桑降糖胶囊中粗多糖平均质量分数为4.56%,总皂苷平均质量分数为2.97%,总黄酮平均质量分数为2.61%;建立了10批次葛桑降糖胶囊的UPLC指纹图谱,确立15个共有峰,经对照品指认出7个共有峰,分别是葛根素、芦丁、三七皂苷R1、人参皂苷Rg1、商陆苷、人参皂苷Rb1、商陆黄素,对应1、5、8、10、12、14、15号峰。结论此方法可用于葛桑降糖胶囊的质量控制。