Lateral flow-based assay for simple and rapid visual detection of Asian-type DEL

Background Where a high prevalence of Asian-type DEL ( RHD*01EL.01 ) occurs, simple, rapid, and accurate tests are required to screen patients and donors. Discriminating between Asian-type DEL and RHD*01N.01 (true D-phenotype) is essential to reduce anti-D alloimmunization. This study aimed to develop a simple, and rapid test to detect Asian-type DEL in serologically D- individuals in a Thai population. Method In this study, we simplified the performance of the polymerase chain reaction (PCR) combined with a lateral flow assay procedure (PCR-LF), providing a rapid and more sensitive detection of the PCR product and validated it for the identification of Asian-type DEL in samples with a serologically D- phenotype. Result In contrast to conventional PCR with agarose gel electrophoresis (PCR-AGE), any PCR products were detected by the lateral flow assay within 10 minutes. This assay accelerates the PCR work schedule and reduces post-PCR detection steps. PCR-LF, PCR-AGE, and Sanger-sequencing assays showed concordant results. The developed PCR-LF assay was more sensitive than an existing PCR-AGE assay for the RHD 1227A allele. The estimated time to perform a PCR-LF assay is 2 hours after DNA extraction compared to the 3 hours 30 minutes for PCR-AGE. Conclusion PCR-LF was developed to detect Asian-type DEL. This method being rapid and easy to perform would be useful for identifying the Asian-type DEL which serological methods are unable to detect. This could improve blood transfusion management and for the selection of the right blood products to prevent anti-D alloimmunization.