Design and testing of multiplex RT-PCR primers for the rapid detection of influenza A virus genomic segments: Application to equine influenza virus.

The research outlines the development of a rapid and cost-effective method to identify viral genomic segments of influenza A viruses using multiplex RT-PCR, specifically studying the H3N8 equine influenza virus (EIV) as an example.

Context and Objectives of the Research

• The research was carried out in the context of needing a quicker and more affordable method to identify new strains of influenza A viruses, which can easily undergo genomic recombination and cause pandemics.
• The goal of designing the multiplex RT-PCR was to alleviate the difficulties of whole genome sequencing which is often time-consuming, expensive, and labor-intensive.
• The authors specifically aimed to develop a technique that would work effectively in detecting and diagnosing the H3N8 EIV, which was used to evaluate the performance of the method.

Process of Development

• The development of the multiplex RT-PCR involved multiple steps, starting with a phylogenetic analysis based on different influenza hosts.
• Next, in silico analyses were conducted to estimate factors such as primer specificity, coverage, and variation scores. These could potentially impact the effectiveness of the PCR amplification.
• The researchers also investigated host-specific amino acids to reduce or eliminate negative influences affecting the process.
• EIV-specific primers were then synthesized using a dual priming oligonucleotides (DPO) system to further augment primer specificity.

Results and Implications

• The resulting process produced 16 primer pairs, which enabled them to screen the eight dominant genome segments of the H3N8 EIV strain.
• The performance of these primers was evaluated using eight sets of four segment combinations from various influenza samples.
• The results suggested that the new multiplex RT-PCR method could have broad applications in detecting and diagnosing newly emerging EIVs. This points to its broader utility in managing and preventing future influenza pandemics.
• The proposed procedures for designing the multiplex primers are also speculated to be valuable for detecting other animal influenza A viruses, extending the reach of this research beyond the EIV.