Evaluation of UPlink–RSV

Abstract

A prototype rapid antigen test for the on-site detection of respiratory syncytial virus (RSV) infection was developed and evaluated. The platform uses instrumented assay analysis, eliminating potential operator bias in the interpretation of the test result that may occur with visually interpreted rapid antigen assays. The device was tested as the first point-of-care (POC) infectious disease application of novel reporter up-converting phosphor technology (UPT) using a specifically designed portable UPT reader (UPlink). Assays were performed by mixing nasopharyngeal specimen with RSV-specific UPT reporter particles and addition of the mixture to a disposable cassette containing a lateral flow (LF) strip with RSV capture antibodies. UPT reporters bound on the specific capture zone were analyzed with the UPlink reader. Reproducibility testing of the UPlink-RSV (UPR) test by naïve users confirmed the potential of UPlink for POC applications where testing is not always performed by highly trained medical staff. The performance of UPR was further evaluated with clinical nasopharyngeal specimens. A prospective study at an independent test site demonstrated clinical parameters of 90% sensitivity and 98.3% specificity with an overall correlation of 96.2% as compared to viral culture with RT-PCR verification. These results are in agreement with in-house retrospective studies and results obtained with other available commercial rapid antigen assays.

A user-friendly, highly sensitive assay to detect the IFN-γ secretion by T cells

“…2B is 601 RFU; calculated as the average zero signal plus 2 std (standard deviation, n=3). An example of a prototype UCP-LF assay that utilizes the test line signal in RFU to determine infection by respiratory syncytial virus (RSV) has been described recently (14). As actual values may show variation when working with several small batches of manually produced LF strips and as values depend on the type of scanner used (portable versus benchtop (12)), scan results are also expressed as a ratio value.…”

“…As up-conversion does not occur in nature, (interfering) auto-fluorescence of other assay components and materials is virtually absent; this feature makes UCP-based assays highly sensitive. The application of UCP in the detection of other antigens has been recently applied for the detection of Respiratory Syncytial Virus (14), Schistosoma species (15) and Yersinia pestis (16). These three assays all use the rapid LF format thus allowing convenient single sample testing.…”

“…These three assays all use the rapid LF format thus allowing convenient single sample testing. The LF strips exposed to UCP reporters can be analyzed with a simple and portable reader that allows a full instrument-assisted assay analysis (14) which avoids operator bias in the interpretation of assay results.…”

Up-Converting Phosphor Technology-Based Lateral Flow Assay for Detection of Schistosoma Circulating Anodic Antigen in Serum

“…The important advantages of UPT reporters compared to other (conventionally applied) fluorescent labels include high sensitivity (no autofluorescence of other biological materials), long shelf life, permanent record (no fading), and low costs (28). Various bioassays, including lateral flow (LF) devices, that demonstrate the usefulness of UPT reporters have been developed (11,12,14,15,21,27,29).…”

Upconverting Phosphor Labels for Bioanalytical Assays

“…Actually, the portable UPlink™ analyzer from OraSure Technologies [161] was commercially launched, but the company has replaced the test platform designed for drugs of abuse with other products not related to the UCPs. Commonly, the research groups have utilized standard spectrofluorometers equipped with an appropriate external excitation source (omitted from Table 5).…”