Pretreatment of mice with oligonucleotide prop5 protects them from influenza virus infections

Area of Science:

• Virology
• Molecular Biology
• Pharmacology

Background:

• Influenza A virus relies on host factors for replication.
• Programmed cell death protein 5 (PDCD5) is a host factor implicated in viral infections.
• Antisense oligonucleotides offer a potential therapeutic strategy against viral pathogens.

Purpose of the Study:

• To evaluate the antiviral efficacy of Prop5, an antisense oligonucleotide targeting PDCD5, against influenza A virus in a mouse model.
• To determine the prophylactic and therapeutic potential of Prop5 in controlling influenza A virus infection.
• To investigate the mechanism of action of Prop5 in reducing viral load and improving survival.

Main Methods:

• A mouse model of influenza A virus infection was established using the mouse-adapted A/FM/1/47 strain.
• Prop5 was administered intranasally at dosages of 10 and 20 mg/kg/d at 24 hours and 30 minutes before infection.
• Viral titers, survival rates, mean survival days, and lung index were assessed.
• Western blotting and immunohistochemistry were used to analyze PDCD5 protein expression in lung tissues.

Main Results:

• Prop5 administration resulted in 80% and 100% survival rates at 10 and 20 mg/kg/d, respectively, significantly prolonging survival compared to controls (p < 0.01).
• Viral titers in the lungs were significantly reduced on days two, four, and six post-infection in Prop5-treated mice (p < 0.05 or p < 0.01).
• The lung index was significantly inhibited in mice treated with 20 mg/kg/d Prop5 on day six post-infection (p < 0.05).
• Prop5 treatment led to down-regulation of PDCD5 protein expression in the lung tissues of infected mice.

Conclusions:

• Antisense oligonucleotide Prop5 demonstrates significant antiviral activity against influenza A virus in a mouse model.
• Prop5 effectively reduces viral load, improves survival rates, and mitigates lung pathology, indicating its potential as a prophylactic and therapeutic agent.
• The findings suggest that Prop5 exerts its antiviral effect by down-regulating PDCD5 expression, offering insights into host-pathogen interactions during influenza infection.