A microarray-based pathogen chip for simultaneous molecular detection of transfusion-transmitted infectious agents

New and emerging transfusion-transmitted infections remain a threat to the blood supply. Blood donors are currently screened for less than half of known agents, primarily by individual tests. A screening platform that could simultaneously detect all known transfusion-transmitted pathogens and allow rapid addition of new targets would significantly increase blood safety and could improve the response to new agents. We describe the early stage development and validation of a microarray-based platform (pathogen chip) for simultaneous molecular detection of transfusion-transmitted RNA viruses.

Sixteen RNA viruses that pose a significant risk for transfusion-transmission were selected for inclusion on the pathogen chip. Viruses were targeted for detection by 1769 oligonucleotide probes selected by Agilent eArray software. Differentially concentrated positive plasma samples were used to evaluate performance and limits of detection in the context of individual pathogens or combinations to simulate coinfection. RNA-viruses detection and concentration were validated by RT-qPCR.

Hepatitis A, B and C, Chikungunya, dengue 1-4, HIV 1-2, HTLV I-II, West Nile and Zika viruses were all correctly identified by the pathogen chip within the range of 10⁵ to 10² copies/mL; hepatitis E virus from 10⁵ to 10⁴. In mixtures of 3-8 different viruses, all were correctly identified between 10⁵ and 10³ copies/mL.

This microarray-based multi-pathogen screening platform accurately and reproducibly detected individual and mixed RNA viruses in one test from single samples with limits of detection as low as 10² copies mL.