Background: Influenza B virus causes influenza-like illness in humans. MicroRNAs
(miRNAs) are small non-coding RNAs regulating gene expression through mRNA degradation or
translational repression. MiRNAs have evolved to regulate many cellular processes including the viral
Objective: This study aims to investigate the miRNA profiles of human cells infected with influenza B
Methods: A549 cells were infected with influenza B viruses (MOI = 0.5). MiRNAs were extracted at
24 and 48 hours post-infection. MiRNAs were used to construct four DNA libraries: influenza Binfected
and an uninfected control for both time points. Then high-throughput sequencing was performed
using the Miseq platform (Illumina). Sequencing data were analyzed by Miseq reporter software.
The miRNAs were categorized and counted based on the frequency of reads. All filtered contigs
were aligned with data from miRbase. The relative expression of each miRNA between uninfected
and influenza B-infected cells was calculated.
Results: There were 13 down-regulated miRNAs and 21 up-regulated miRNAs observed in influenza
B infected cells at 24 hours post infection. At 48 hours post infection, 14 miRNAs were downregulated,
whereas 8 miRNAs were up-regulated.
Conclusion: This study suggested that miRNAs may play important roles in host gene regulation in
response to viral infection.