Guest author: Han Joo Lee, Ph.D., SeraCare Technical Product Manager
A cursory look at recent Zika Virus outbreak news headlines is alarming enough: “Zika Virus birth defects may be the ‘Tip of the Iceberg’, experts say”; “Brain damage in Zika babies is far worse than doctors expected”; and “Zika mutates extremely quickly, which is why it’s so scary”. In addition, for the United States the estimated range maps of the Aedes aegypti and Aedes albopictus have been recently updated, widening the range previously reported to all but 10 states within the US.
To deal with the emerging Zika virus epidemic, moleculardiagnostic assay developers, researchers and clinical laboratories have an urgent need to develop, optimize and monitor their Zika assays in the most reliable, robust and timely manner. The key components to any successful and rapid development of the molecular diagnostic assays are manufactured controls. These controls must adequately represent the virus genetically and function in the appropriate assay format and sample matrix.
SeraCare launched an AccuPlex™ Zika virus reference material to assist in the development and validation of molecular diagnostic assays to the virus.
Based on SeraCare’s patent pending AccuPlex recombinant virus technology, AccuPlex Zika reference material contains the entire RNA genome of the ZIKV 2007 strain in four separate overlapping virus constructs. Each construct’s engineered genome length and its tertiary structure are similar to those of the Zika virus. The AccuPlex recombinant Zika reference material is a mammalian RNA virus that closely mimics the Zika virus in both size and complexity. The AccuPlex Zika reference material lacks the genes required to produce new viral particles and is therefore replication defective. Furthermore, the virus is heat-treated, to assure that the virus is non-replicative but without interfering with target detection in a diagnostic molecular assay.
The AccuPlex Zika reference material is formulated at ~1.0E+05 copies/mL in 0.25mL of defibrinated human plasma. The copy number of the AccuPlex Zika reference material is assigned based on an in-house developed digital PCR assay. Ongoing accelerated and real time stability studies indicate that AccuPlex recombinant viruses are stable at room temperature for at least 20 months and at 4 ºC for at least two years. Other technologies that package the viral RNA into a non-mammalian virus particle may not represent the complexity of the Zika virus found in patient samples.
The AccuPlex Zika recombinant reference material can be an ideal format for laboratories looking to fast-track their development of molecular tests against the Zika virus as well as a powerful tool for public health agencies to implement training, verification and proficiency programs with safe, non-infectious, fully extractable materials.
More information about SeraCare’s AccuPlex Zika Reference material can be found here.