量子点标记链酶亲合素-生物素系统用于抗核抗体检测的对比研究与评价

目的对比研究不同颜色量子点(QDs)标记链霉亲合素(SA)-生物素系统在抗核抗体(ANA)间接免疫荧光实验(IIFA)检测中的效果,评价其在临床样本检测中的应用价值。方法 Hep-2细胞为抗原片,分别以QD655-SA、QD605-SA、QD565-SA结合生物素化羊抗人Ig G(生物素化二抗),用IIFA检测临床样本血清ANA,以异硫氰酸荧光素(FITC)标记二抗(FITC-二抗)为对照。比较和评价3种QDs-SA的应用效果。结果对114例患者血清研究发现,QD655-SA、QD605-SA、QD565-SA结合生物素二抗检测可见与FITC-二抗检测ANA结果相同或类似的荧光模式,阳性结果符合率均为100%,平均抗体滴度均高于FITC-二抗标记检测结果(P0.01)。尤其对核仁型、核均质型与核点型ANA荧光模式检测效果优于FITC-二抗结果。相关分析结果显示:QD655-SA、QD605-SA、QD565-SA与FITC-二抗标记ANA定性结果高度一致(Kappa=0.979),滴度均呈高度正相关(P均0.01)。结论 QDs-SA用于IIFA法检测ANA总体结果稳定、灵敏、可行,可获得较FITC-二抗检测更加敏感和稳定的实验结果。     

抗核抗体核型与抗核抗体谱3(IgG)相应抗体的关系研究

目的 探讨抗核抗体(ANA)荧光核型与ANA 谱3(IgG)15 项抗体之间的关系.方法 对济宁医学院附属医院门诊及住院的自身免疫性疾病(AID)患者进行检测,ANA 采用间接免疫荧光法检测,ANA 谱3(IgG)15 项抗体采用欧蒙免疫印记法检测.结果 362 例ANA 阳性标本中单一核型中核均质型72 例,核颗粒型135 例,胞浆颗粒型26 例,核仁型11 例,着丝点型20 例,核膜型1 例,细胞骨架型2 例,高尔基体型1 例,其余为混合核型,其中ANA 谱3(IgG)15 项抗体阳性率为84.3%(305/362).核均质型常见抗体为抗核小体、Ro-52、dsDNA、组蛋白抗体.核颗粒型常见抗体为抗Ro-52、SSA、nRNP、SSB、Sm 和抗RIB 抗体.胞浆颗粒型常见抗体为抗Ro-52、SSA 和抗RIB 抗体.结论 ANA 是AID 的筛查实验,而ANA 谱3(IgG)15 项抗体对于AID 具有鉴别意义,两者需要平行检测,防止漏诊,通过核型找到ANA 谱3(IgG)15 项抗体中相对应的阳性抗体,提高诊断率.     

2006-2011年中国临床实验室检测自身抗体的室间质量评价

目的 评价我国临床实验室检测自身抗体的能力.方法 每年进行2次室间质量评价,每次发放5支质评样本;要求各临床实验室在规定时间内检测,并回报抗核抗体(ANA)定性结果、核型、滴度、抗可提取核抗原(ENA)抗体和抗dsDNA抗体定性结果,同时计算各项结果的符合率.结果 2006-2011年期间采用IIF检测ANA的实验室比例从77.6％ (149/192)增长到82.2％( 342/416),采用酶联免疫吸附测定法(ELISA)检测ANA的实验室比例在14.5％ (53/365)至16.0％( 52/326)之间.用IIF法检测ANA阳性符合率在2006-2011年期间均在98％以上,ELISA检测的阳性符合率均在90％以上,IIF法每年的阳性符合率均高于ELISA.ANA核型仅为颗粒型的质评样本,除0613和0624号样本外,核型回报结果正确率均＞90％.ANA核型仅为均质型的样本,核型回报结果正确率均≥95％.ANA核型为着丝点型的样本,2007年核型回报正确率仅为88.5％( 161/182)、79.0％ (147/186),2010年提高到98.4％ (299/304),核型回报正确率呈明显上升趋势.各阳性样本中,报告滴度代码结果为中位数的实验室比例最低的仅为36％ (94/261),最高的为85.5％( 224/262).抗ENA抗体总符合率均＞90％,dsDNA抗体总符合率均＞85％.结论 IIF法是我国临床实验室进行ANA筛查的主要方法,其次为ELISA,2种方法对ANA定性回报的结果均较为理想.临床实验室对单一着丝点核型的判断有了很大提高,但是对滴度结果的报告尚不理想.ANA检测还有待标准化.     

抗核抗体荧光模型与抗核抗体谱对应关系研究

目的探讨间接免疫荧光法检测抗核抗体(ANA)荧光模型与ANA谱(包括抗ds DNA、抗RNP、抗Sm、抗SSa、抗SSb、抗Scl-70、抗Jo-1和抗rib-P)检测结果的对应关系。方法回顾性分析2010年1月-2013年12月间7 385例ANA荧光模型与ANA谱中8种特异性自身抗体之间的对应关系。ANA采用以人喉表皮样癌细胞为底物的间接免疫荧光法(IIF法)检测;ANA谱中的抗ds DNA采用以绿绳短膜虫为底物的IIF法检测,其他7种抗体采用纯化抗原的免疫条带法检测。结果 ANA荧光模型为颗粒型主要见于抗RNP、抗Sm、抗SSa及抗SSb(P<0.001);均质型主要见于抗ds DNA及抗SSa(P<0.001);核仁型、着丝点型、复合荧光模型主要见于抗SSa(P<0.05);胞浆型主要见于抗rib-P和抗SSa(P<0.05);而高尔基体型、核点型、周边型、肌动蛋白型、原肌球蛋白型、增殖细胞核抗原(PCNA)型、波形蛋白型荧光模型时8种自身抗体的检出率均较低甚至无法检出。当单纯抗ds DNA阳性时荧光模型为均质型出现频率高达77.91%(P<0.001);单纯抗RNP或抗SSa或抗Sm时为颗粒型出现频率分别为96.84%、52.01%和82.35%(P<0.001);单纯抗Scl-70阳性时均质型与核仁型2种复合荧光模型的出现频率达30.53%(P<0.001);抗rib-P和抗Jo-1阳性时胞浆型的出现频率分别为50.00%和61.54%(P<0.05),但单纯抗SSb阳性时并未发现优势荧光模型。结论 ANA荧光模型与ANA谱之间具有一定的规律。颗粒型、均质型、胞浆型荧光模型可对应多种自身抗体;而着丝点型、高尔基体型、核点型、周边型、肌动蛋白型、原肌球蛋白型、PCNA型、波形蛋白型8种临床常规检测的自身抗体的检出率均很低;抗ds DNA主要对应ANA均质型,抗RNP、抗SSa及抗Sm主要对应颗粒型,抗Scl-70主要对应均质核仁复合型,抗rib-P和抗Jo-1主要对应胞浆型,该结果可为临床医生检验项目申请及实验室结果核对提供依据。     

新疆地区564例抗核抗体阳性结缔组织病患者的荧光核型及靶抗原分析

摘要：目的：了解新疆地区结缔组织病（CTD）患者血清中抗核抗体（ANA）荧光核型、靶抗原与CTD之间的相关性。 方法：采用间接免疫荧光法（IIF）检测ANA荧光核型;采用免疫印迹法和酶免疫法检测抗核抗体谱和自身抗体。 结果：新疆地区564例ANA阳性CTD患者中,ANA荧光核型有单一及复合核型。单一核型中核颗粒型最多见（靶抗原依次为SSA、nRNP、Sm）,其次核均质型（靶抗原依次为dsDNA、核小体和组蛋白）。复合核型中,双核型以核颗粒型+核均质型,核颗粒型+胞浆颗粒型组合为主。三核型以核颗粒型+核均质型+胞浆颗粒型常见。在荧光核型、靶抗原及疾病关系分析结果中发现：SLE患者单核型以核均质和核颗粒最常见,双核型以核颗粒+核均质、核颗粒+胞浆颗粒组合常见,三核型为核颗粒、核均质、胞浆颗粒同时出现。另外抗核糖体P蛋白以往引起胞浆颗粒荧光,而本研究中核颗粒型检出率为27.03%。抗着丝点抗体在SLE、原发性胆汁性肝硬化（PBC）、硬皮病及重叠综合征中均能检出。 结论：新疆地区CTD患者血清ANA荧光核型呈现多样性。以核颗粒为优势核型;靶抗原SSA不仅可以引起经典的核颗粒荧光,还可呈现核均质、核仁型、胞浆颗粒型荧光。核糖体p蛋白呈现核颗粒型荧光。抗着丝点抗体具有较宽的疾病谱;SLE患者荧光核型呈现多样性,自身抗体谱广于其他自身免疫性疾病（AID）。     

312例抗核抗体与抗细胞核细胞浆抗体谱检测结果的分析

目的 回顾分析抗核抗体(ANA)与抗细胞核细胞浆抗体谱(ANA谱)在本实验室的应用状况,以及在自身免疫性疾病诊断上的价值.方法 ANA用间接免疫荧光法检测,ANA谱用欧蒙印迹法检测.结果 312例临床标本中,ANA阳性数为123例,阳性率为39.9%(123/312),核型种类主要为核细颗粒型、均质型和核仁型等,滴度各有不同.312例标本同时做ANA谱检测,阳性数为88例,阳性率为25%(88/312).阳性抗体出现次数较多的是抗SSA、Ro52、SSB、CENPB(着丝点B蛋白)和Histone(组蛋白)等,基本上与荧光法测定ANA核型的结果相符.只是当ANA为低滴度(起始滴度1:100)时,ANA谱为阴性结果的可能性较高.结论 用间接免疫荧光法筛查ANA,再用ANA谱作确认分型,可以更准确地确定ANA靶抗原的类型,ANA谱可检测15种针对细胞核和细胞浆的抗体,同传统的抗ENA抗体六项相比,扩大了检测范围,增强了对ANA的分型能力,具有较高的应用价值.     

抗核抗体核型与条带免疫抗体谱相关性分析

目的分析抗核抗体(antinuclear antibody,ANA)与抗核抗体谱(antinuclear antibodies,ANAs)的相关性。方法 2 500例疑似或已确诊自身免疫性风湿性疾病患者,采用间接免疫荧光法检测ANA,其中826例同时应用条带免疫分析法行ANAs分析。结果 ANA阳性1 300例,同时行ANAs的826例患者中ANA(+)/ANAs(+)182例(22.03%),ANA(-)/ANAs(-)529例(64.04%),ANA(+)/ANAs(-)111例(13.43%),ANA(-)/ANAs(+)4例(0.50%);ANA阳性者中以颗粒型(62.2%)、胞质颗粒型(13.3%)、均质型(9.7%)、核仁型(8.9%)多见,颗粒型多见SSA/Ro52抗体,均质型多见dsDNA抗体,胞质颗粒型多见AMA-M2;ANAs的阳性率随ANA滴度增大而升高;当滴度为1∶800以上时,>20～40岁组ANA阳性率明显高于其他各年龄组(P<0.01)。结论 ANA-间接免疫荧光法是良好的筛查实验,ANA核型、滴度与ANAs相结合对自身免疫性风湿性疾病的诊断与鉴别诊断有重要意义。     

回顾性分析抗核抗体单一荧光核型与抗核抗体谱分型的关系

目的分析抗核抗体(ANA)单一荧光模型阳性的样本免疫印迹法检测的结果,探讨两者的相关性,并研究是否能通过荧光模型初步判断其特异性抗体。方法回顾性分析347例ANA单一荧光模型阳性标本,对比间接免疫荧光法和免疫印迹法检测的符合率。结果 347例间接荧光法ANA阳性标本,其中自身免疫性疾病标本137例,非自身免疫性疾病标本210例,免疫印迹法检测ANA阳性例数分别为100、60例,符合率分别为73.0%、28.6%。核型主要以核颗粒型为主,多出现抗SSA、抗SSB、抗Ro52抗体,高尔基体型、肌动蛋白型核型等核型少见。仅有3例标本的核仁型在分型中出现条带。着丝点型多会出现抗着丝点抗体,特异性高。结论在自身免疫性疾病患者中,间接免疫荧光法和免疫印迹法两者具有较高的相关性,但因其具有各自的局限性,应将两者结合起来,报告荧光核型。     

抗着丝点抗体在肝病患者中的检测及其意义

目的探讨抗着丝点抗体(ACA)的肝功异常患者中出现的频率、特点及其临床意义。方法对10000例肝功异常患者采用间接免疫荧光法检测抗核抗体(ANA)、抗线粒体抗体(AMA)、抗平滑肌抗体(SMA)和抗细胞骨架抗体等,并采用免疫印迹法检测抗着丝点抗体及其它抗可提取的核抗原(antextractablen2uclearantigens,ENA)抗体。结果 (1)10000例肝功异常患者中,间接免疫荧光法筛选结果显示抗核抗体阳性,着丝点型的患者为134例,占1.34%。其中滴度1∶100的占35.8%;滴度1∶320的占40.3%;滴度大于等于1∶1000的占23.9%。滴度大于等于1:320的患者再免疫印迹法检测,抗着丝点抗体均为阳性。部分患者伴有其他核型的抗核抗体以及抗线粒体抗体等自身抗体。(2)134例ACA阳性患者,诊断为硬化型肝病的有83例,包括PBC、PBC和AIH重叠症、肝炎肝硬化以及原发性肝癌硬化型。诊断为非硬化型肝病的有51例,包括病毒性乙型肝炎、自身免疫性肝炎、药物性肝炎和病毒性丙型肝炎等。抗着丝点抗体高滴度组患者的肝硬化发生率明显高于低滴度组。(3)分析高滴度组(滴度大于等于1∶320)和低滴度组(滴度1∶100)组的实验室检查结果发现,ACA高滴度组AST/ALT比值明显高于低滴度组,ALB和PA明显低于低滴度组,IgM的含量也高于低滴度组,两组间的差别有统计学意义。结论肝病患者中,抗着丝点抗体并不少见,高滴度的抗着丝点抗体更见于各种原因引起的肝硬化患者。     

2513例抗核抗体与抗核抗体谱检测结果对比分析

目的分析本实验室抗核抗体(ANA)与抗核抗体谱(ANAs)15项联合检测的结果,并探讨两者之间的关系。方法分别用间接免疫荧光法(IIF)和免疫印迹法(IBT)检测患者ANA和ANAs,判断其ANA滴度、荧光模型和ANAs结果,并对ANA和ANAs检测结果进行对比分析。结果 471例ANA阳性患者标本中,颗粒型161例,均质型110例,胞质型96例、核仁型37例、着丝点型28例,其他型合计39例;滴度为1∶100者196例,占41.61%(196/471),其中ANAs阳性53例,占27.04%(53/196);滴度为1∶320者123例,占26.11%(123/471),其中ANAs阳性67例,占54.47%(67/123);滴度为1∶1 000者152例,占32.27%(152/471),其中ANAs阳性132例,占86.84%(132/152);2 042例ANA阴性标本中45例ANAs检测阳性,阳性率为2.2%(45/2042);高滴度ANA患者血清中ANAs的阳性率高于低滴度(χ2=123.132,P0.05)。结论不同滴度的ANA与ANAs之间有一定的关系,如果以ANA进行过筛,阳性再做ANAs会漏检部分患者,建议IIF和IBT联合应用,防止风湿病的漏诊。     

基于量子点标记技术在人血清甲胎蛋白中的意义

目的建立1种基于新型纳米颗粒——量子点(QD)作为荧光标志物检测人血清甲胎蛋白的新方法。方法生物素标记的甲胎蛋白单克隆抗体与血清中的甲胎蛋白抗原特异性结合形成抗原抗体复合物,耦联生物素的QD-605和QD-655作为荧光标志物与抗原抗体复合物结合,借助磁场的清洗分离效应,去除反应体系中的非特异性物质,利用荧光分光光度计检测QD标记的甲胎蛋白抗原抗体复合物的荧光强度及光谱。结果用350nm波长的光作为激发光,量子点QD-605单独作为标志物时,荧光发射谱在605nm处有1个波峰;QD-655单独作为标志物时,荧光发射谱在655nm处有1个波峰;QD-605和QD-655混合作为标志物时,荧光发射谱出现2个波峰,分别在605和655nm处。结论本选题利用QD标记技术检测血清中的甲胎蛋白,有望为临床免疫诊断学提供1种更快捷、有效的方法。     

纯V型狼疮性肾炎与膜性肾病的临床病理分析

目的 发现提示早期V型狼疮性肾炎(1upus nephritis,LN)的指标.方法 2004年1月-2009年11月24例经肾活检诊断为V型LN患者,与同期50例膜性肾病伴抗核抗体(antinucIear antibody,ANA)阳性患者、50例膜性肾病ANA阴性患者,以及13例膜性肾病ANA阳性且肾组织荧光为"满...     

2325例患者抗核抗体核型与抗核抗体谱检测结果分析

目的探讨抗核抗体(ANA)核型与抗核抗体谱(ANAs)检测的临床应用价值。方法分别采用间接免疫荧光法(IIF)和线性免疫印迹法(LIA)对2 325例自身免疫性疾病(AID)确诊及疑似患者ANA和ANAs进行检测,分析ANA核型和ANAs检测结果。结果 2 325例患者中,检出ANA阳性896例,阳性率为38.54%,女性患者阳性率(45.46%)高于男性患者(18.46%,P0.05),常见荧光核型为核颗粒型、核均质型、核仁型;检出ANAs阳性816例,阳性率为35.10%,阳性率较高的分别为抗干燥综合征(SS)-B抗体、抗Ro-52抗体、抗SS-A抗体等。两种方法检测结果一致率为91.66%。结论 IIF法ANA检测结果和LIA法ANAs检测结果具有一定的相关性,但并不完全一致;二者联合检测具有互补性,可提高检出率,避免漏诊。     

Optimizing quantitative in vivo fluorescence imaging with near‐infrared quantum dots

Quantum dots (QDs) are fluorescent nanoparticles with broad excitation and narrow, wavelength‐tunable emission spectra. They are used extensively for in vitro fluorescence imaging studies and more recently for in vivo small animal and pre‐clinical studies. To date there has been little concern about the selection of QD size (and thus emission wavelength peak) and excitation wavelengths, as they have little relevance to the results of in vitro studies. In vivo imaging, however, poses additional constraints, such as the scattering and absorption by tissue, which may influence the signal intensity at the body surface. Here, we demonstrate that longer‐wavelength excitation and emission yield less quantization error in measured relative fluorescence intensity, using three near‐infrared QDs (QD655, QD705 and QD800) applied to in vivo lymphatic imaging, and a range of excitation wavelengths from the blue to the red. Statistically significant differences in quantization error were observed between nearly all pairs of excitation wavelengths (445–490, 503–555, 575–605, 615–665 and 671–705 nm). Similarly, quantization error decreased with longer emission wavelengths (655, 705 and 800 nm). Light absorbance and scattering were demonstrated to be more potent factors than absorbance efficiency of QDs in producing quantization error in the measured fluorescence intensity. As a result, while wavelengths can be adjusted for qualitative experiments, the longest possible wavelengths should be used if quantification is desired during QD imaging experiments. Copyright © 2010 John Wiley & Sons, Ltd.     

1801例抗核抗体检测结果及其临床分析

目的 探讨抗核抗体(ANA)的流行病学特征及其与临床的相关性.方法 回顾性分析1 801例ANA检测结果及其临床资料.结果 (1)ANA阳性604例,总阳性率为33.5%,其中82.5%为女性患者.60岁以下各年龄组女性患者阳性率均高于男性(P<0.05),而以36～45岁组阳性率最高.(2)ANA荧光模型以细胞核型荧光(67.4%)最常见,以核颗粒型(43.7%)为主.(3)ANA阳性患者特异性抗体总阳性率为47.8%.混合型特异性抗体阳性率最高(57.8%),细胞浆型(12.7%)最低(P<0.01).抗核点型、抗核膜型、抗着丝点型及抗中心粒抗体阳性患者均未检出特异性抗体.(4)ANA阳性者66.2%诊断为自身免疫性疾病(AID),显著高于ANA阴性者(17.0%),差异有统计学意义(P<0.01).混合型ANA组73.6%诊断为AID,其次为细胞核型ANA组(70.2%),最低为细胞浆型ANA组(36.9%),后者与前两组比较,差异有统计学意义(P<0.01).系统性红斑狼疮(SLE)组ANA阳性率最高.SLE、类风湿关节炎(RA)、混合结缔组织病(MCTD)、系统性硬皮病(SS)、多发性肌炎(PM)/皮肌炎(DM)、重叠组织病患者ANA阳性率与非AID患者比较,差异有统计学意义(P<0.05),而强直性脊柱炎(AS)、成人斯蒂尔病(STILL)患者与非AID患者比较,差异无统计学意义.SLE、RA、MCTD患者ANA模型均以核颗粒型为主.滴度达1∶3 200者89.1%诊断为AID,其次为滴度达1∶1 000者(72.2%)与滴度达1∶320者(44.7%),3组间比较,差异均有统计学意义(P=0.000).结论 不同性别和年龄患者ANA阳性率存在差异;ANA存在多种荧光模型,不同荧光模型ANA阳性患者特异性抗体检出率存在差异,部分ANA阳性患者不能检测出特异性抗体;高滴度ANA对于AID诊断有重要意义,但ANA荧光模型对不同AID疾病的诊断无特异性.     

系统性红斑狼疮患者血清抗核抗体免疫荧光核型与特异性抗体谱的相关分析

目的　探讨系统性红斑狼疮 (systemic lupus erythematosus, SLE）患者血清抗核抗体 (antinuclear antibody, ANA) 免疫荧光核型与特异性抗体谱（antinuclear antibody profile, ANAs）之间的相关性。方法　回顾性调查和分析2015 年1 月~2018 年12 月263 例SLE 住院患者的ANA 及ANAs 实验结果。线性免疫印迹法（Line-blot immunoassay, LIA）检 测ANAs,间接免疫荧光法（indirect immunofluorescence, IIF）检测ANA,荧光显微镜下核对ANA 免疫荧光滴度和特 异性荧光核型。对荧光核型与特异性抗体谱结果进行统计分析。结果　① 263 例SLE 患者血清IIF-ANA 检测阳性率为 94.29 %,LIA-ANAs 检测阳性率为89.73 %,二者差异无统计学意义（χ2= 3.73,P> 0.05）;IIF-ANA 和LIA-ANAs 检 测结果的总体一致率为89.35 %,二种方法检测结果不一致,差异具有统计学意义（χ2= 263,P < 0.05）,检测一致性 较差（Kappa = 0.281,P< 0.05）;② IIF-ANA 阳性病例中,随着ANA 滴度增加,LIA-ANAs 阳性率逐渐增高,不同 ANA 滴度组LIA-ANAs 阳性率差异具有统计学意义（χ2=22.93,P < 0.05）;③ IIF-ANA 阳性患者免疫荧光核型以核颗 粒型（68.54%）和核均质型（32.26 %）为主;核颗粒型多为ds-DNA 和RNP 抗体为主,核均质型多为ds-DNA 和核小 体抗体为主。结论　不同荧光核型ANA 与ANAs 抗体间具有一定相关性,IIF-ANA 筛查与 LIA-ANAs 特异性抗体确认 实验联合检测,有助于提高自身抗体阳性检出率,为SLE 的准确诊断和及时治疗提供有价值的参考依据。     

Relevance of autoantibody detection to the rapid diagnosis of brucellosis

The rose bengal test is often used for rapid diagnosis of human brucellosis in endemic areas. However, autoantibodies have never been investigated as a reason for false-positive or false-negative results. Therefore, the aim of this study was to show the effect of autoantibody detection on the rapid diagnosis of human brucellosis in an endemic area. The study included 2 groups: antinuclear antibody (ANA)-positive and ANA-negative groups. Diagnosis of brucellosis was established by isolation of Brucella spp. from blood culture. The overall sensitivity and specificity of the rose bengal test were 100% and 90.8%, respectively. The specificity (100% versus 89%) and positive predictive value of the test (100% versus 8%) fell markedly from the ANA-negative to the ANA-positive group. As a conclusion, this study verified our suspicion about the effect of autoantibodies on rose bengal test results to the diagnosis of human brucellosis. However, to have definite decisions, extensive studies with larger populations are needed.     

Analysis of antinuclear antibody titers and patterns by using HEp-2 and primate liver tissue substrate indirect immunofluorescence assay in patients with systemic autoimmune rheumatic diseases

BackgroundIndirect immunofluorescence assay (IIFA) is viewed as a preliminary standard to assess antinuclear antibodies (ANAs). Our aim was to explore ANA positivity rate, titers, and patterns in patients with systemic autoimmune rheumatic diseases (SARD), including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), primary Sjögren''s syndrome (pSS), systemic sclerosis (SSc), and mixed connective tissue disease (MCTD), compared with healthy controls (HC).MethodsAssess antinuclear antibody titers and patterns were retrospectively identified and compared by IIFA using human epithelial cells (HEp‐2) and primate liver tissue substrate according to international consensus in SARD. Serum complement 3 (C3), C4, and immunoglobulin G were compared among subgroups with different ANA titers. The positive predictive values (PPV) for different ANA titers were calculated.ResultsThere were a total of 3510 samples, including 2034 SLE, 973 RA, 155 SSc, 309 pSS, and 39 MCTD cases. There was no difference in age between HC and SARD, excluding RA. ANA positivity rate in SARD and HC was 78.7% and 12.2%, respectively. A titer of ≥1:320 revealed a PPV of 84.0% in SARD. SLE patients with ANA titers ≥1:320 had significantly lower levels of C3 and C4. AC‐4 (31.2%) was the major pattern in patients with SARD, followed by AC‐5 (23.9%) and AC‐1 (18.8%). SLE mostly presented with AC‐4 (30.3%). Several mixed patterns provided a significant hint for SSc and SLE. The major pattern in HC was AC‐2 (12.2%).ConclusionsAssess antinuclear antibody positivity, titers, and patterns display differences in various SARD, contributing to the classification of SARD.     

Evaluation of the LIA-ANA-Profile-17S for the detection of autoantibodies to nuclear antigens

ObjectivesThe diagnostic tests for autoimmune disease include screening for autoantibodies for nuclear antigens (ANA) and antibodies against extractable nuclear antigens (ENA). Using the line immunoassay (LIA) method, various kinds of ENA antibodies can be detected simultaneously. We evaluated the performance of the newly launched LIA-ANA-Profile-17S (Shenzhen YHLO Biotech, Shenzhen, China) as compared to a conventional LIA kit.MethodsResidual samples were collected from 200 patients who had been tested for ANA using indirect immunofluorescence. The LIA-ANA-Profile-17S was compared to the EuroLine ANA (Euroimmun, Oberlausitz, Germany) for the analysis of 17 different autoantibodies. The concordance rate and agreement between assays were determined. Samples showing discrepancies between the LIA-ANA-Profile-17S and EuroLine tests were further examined through additional analysis.ResultsThe overall agreement was moderate (kappa = 0.759, 95% CI = 0.712–0.805). Agreement between assays ranged from weak to almost perfect, except for those tests targeting nucleosomes, histones, and PM-Scl. Of the 57 disparate results between LIA-ANA-Profile-17S and EuroLine, 38 (66.7%) samples tested positive under an additional assay, showing variable patterns between types of autoantibodies. The positive rate of each autoantibody between LIA-ANA-Profile-17S and EuroLine did not differ significantly, except for anti-nucleosome and anti-histone assays in samples from patients diagnosed with systemic lupus erythematosus (P = 0.004 and 0.001, respectively).ConclusionsCompared to those from the conventional EuroLine assay, the LIA-ANA-Profile-17S results showed variable agreement in samples showing different prevalence of each autoantibody. The most frequently detected antibodies showed almost perfect agreement. The LIA-ANA-Profile-17S could play a role in the diagnosis of systemic autoimmune disease in ANA-positive samples.     

Detection and identification of significant ANAs in previously determined ANA negative samples

BACKGROUND: An antinuclear antibody (ANA) substrate transfected with the cDNA to hyperexpress the 60 kD SS-A/Ro antigen (HEp-2000) has been shown to detect anti-SS-A/Ro antibodies missed by standard HEp-2 and other immunoassays. Despite this evidence, many laboratories remain convinced that with experienced technicians, standard HEp-2 is acceptable for ANA detection. AIM: To challenge the ability of HEp-2000 to detect anti-SS-A/Ro antibodies in samples previously determined to be ANA negative using standard HEp-2. METHODS: Three hundred and seventy-one pre-screened "negative" ANA samples were provided by a university hospital laboratory in Germany. These samples were tested on the HEp-2000 substrate at a dilution of 1:40 by indirect immunofluorescence (IIF). Samples that screened positive for a nuclear pattern were titered (range of 1:40-1:640) and all ANA-positive patterns were identified. Samples containing at least one positive ANA pattern at a dilution greater than or equal to 1:160 were further tested. Samples that produced a speckled pattern were tested for antibodies to the extractable nuclear antigens (ENA) and samples that showed homogeneous staining were tested for antibodies to dsDNA, and if negative, were then tested for anti-histone antibodies. RESULTS: Ninety-one patient samples were positive with titers > or =1:160. Speckled patterns were the most common finding (30 samples) followed by speckled/homogeneous mixed patterns (19 samples) and samples demonstrating the SS-A/Ro pattern (16 samples) either alone or in combination with other ANA patterns. The remaining 26 positive samples consisted of various other ANA patterns. The most commonly identified ENAs were SS-A/Ro (14 samples), Scl-70 (11 samples) and SSB (6 samples). No antibodies to dsDNA were identified in 23 positive samples with homogeneous staining patterns, though 17 of these samples tested positive for antibodies to histone. CONCLUSIONS: HEp-2000 detected anti-SS-A/Ro antibodies in 16 (4%) of the "ANA negative" samples. In addition to improved sensitivity for anti-SS-A antibodies, HEp-2000 demonstrated improved sensitivity over standard HEp-2 substrate for other significant ANAs including anti-Scl-70, anti-histone, and anti-SS-B antibodies.