Distinct Roles of Interferon Alpha and Beta in Controlling Chikungunya Virus Replication and Modulating...

Area of Science:

• Immunology
• Virology
• Infectious Diseases

Background:

• Type I interferons (IFNs) are crucial for innate immunity against viruses.
• While IFNs share a receptor, subtypes like IFN-α and IFN-β have distinct functions.
• The specific roles of IFN-α and IFN-β in chikungunya virus (CHIKV) infection are not fully understood.

Purpose of the Study:

• To investigate the distinct roles of IFN-α and IFN-β in CHIKV pathogenesis.
• To elucidate the mechanisms by which these IFN subtypes confer protection against CHIKV.

Main Methods:

• Evaluated CHIKV infection in mice lacking IFN-α (IRF7-KO) or IFN-β (IFN-β-KO).
• Utilized IFN-α and IFN-β blocking antibodies to assess subtype-specific effects.
• Assessed viral loads, clinical disease severity (foot swelling), and immune cell infiltration (neutrophils).

Main Results:

• Mice lacking either IFN-α or IFN-β exhibited severe CHIKV disease and increased foot swelling.
• IFN-α deficiency led to higher viral burdens in infected and distant tissues.
• IFN-β deficiency resulted in increased neutrophil infiltration into musculoskeletal tissues, exacerbating disease.

Conclusions:

• IFN-α limits early CHIKV replication and dissemination.
• IFN-β modulates neutrophil-mediated inflammation, protecting against CHIKV-induced musculoskeletal pathology.
• IFN subtypes play distinct, complementary roles in controlling CHIKV infection and pathogenesis.