Prozone effect on indirect immunofluorescence assay for anti-nuclear antibody testing
10.3969/j.issn.1673-4130.2019.02.022
- VernacularTitle:间接免疫荧光试验检测抗核抗体的前带效应分析
- Author:
Qiongwen HU
1
;
Chaojun HU
;
Ping LI
;
Chuiwen DENG
;
Ziyan WU
;
Xiaofeng ZENG
;
Fengchun ZHANG
;
Pu LIAO
;
Yongzhe LI
;
Shulan ZHANG
Author Information
1. 中国医学科学院/北京协和医学院风湿免疫科
- Keywords:
prozone effect;
indirect immunofluorescence assay;
anti-nuclear antibody
- From:
International Journal of Laboratory Medicine
2019;40(2):210-213
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the influence of prozone effect on anti-nuclear antibodies (ANA) testing by indirect immunofluorescence assay (IIFA).Methods The samples with high titer of ANA (≥1∶1 000) were selected from 880fresh serum samples, and were subsequently diluted in 1∶100, 1∶1 000and 1∶10 000ratio.Prozone effect was defined as fluorescence intensity from 1∶1 000dilution was stronger than that from1∶100dilution.The samples with prozone effect were determined manually or by Sprinter XL and EUROPattern.The samples with prozone effect were further characterized by combinations of fluorescence patterns, fluorescence intensities and autoantibody specificities.Results A total of 880samples were tested.Importantly, 34samples displayed prozone effect (3.86％in total and 29.57％in samples with ANA≥1∶1 000).Interestingly, prozone effect was identified by manual detection as well as by Sprinter XL with similar fluorescence patterns and fluorescence intensities.Notably, EUROPattern can only select the central area for identification.Among all samples with prozone effect, 74.42％samples exhibited fluorescence intensities of≥1∶10 000.Speckled pattern was the most prevalent fluorescence patterns in samples with prozone effect (46.51％).In addition, anti-RNP antibodies (62.79％) were the most popular autoantibodies in samples with prozone effect, followed by anti-dsDNA antibodies (51.16％) and anti-SSA antibodies (51.16％).Conclusion Prozone effect was present in ANA testing, especially in samples with high titers, resulting in underestimating the titers.The study highlighted that special attention should be paid to the prozone effect in clinical practice.
