Remdesivir postexposure prophylaxis limits measles-induced "immune amnesia" and measles antibody responses in...

Area of Science:

• Immunology
• Virology
• Pharmacology

Background:

• Measles virus (MeV) infection causes significant global child morbidity and mortality.
• MeV infection impairs the immune system, leading to a loss of antibodies against other pathogens, increasing susceptibility to secondary infections.
• Remdesivir is a broad-spectrum antiviral agent with potential immunomodulatory effects.

Purpose of the Study:

• To investigate the effect of remdesivir on MeV-induced loss of antibodies to other pathogens.
• To assess how remdesivir treatment timing impacts both MeV-specific antibody responses and antibody levels to non-MeV pathogens.

Main Methods:

• Expanded VirScan technology to detect antibodies against human and macaque pathogens.
• Measured antibody reactivity to MeV and non-MeV viral peptides in plasma from MeV-infected macaques.
• Compared outcomes in macaques receiving remdesivir as postexposure prophylaxis (PEP) or late treatment (LT) versus untreated controls.

Main Results:

• Remdesivir PEP (early treatment) prevented the loss of antibodies to non-MeV pathogens.
• Remdesivir PEP also reduced the magnitude and breadth of the MeV-specific antibody response.
• Late treatment (LT) with remdesivir did not prevent antibody loss to other pathogens and had minimal effect on the magnitude but reduced the breadth of the MeV-specific antibody response.

Conclusions:

• Early administration of remdesivir (PEP) can mitigate the immunosuppressive effects of measles, preserving antibody levels to other pathogens.
• While early remdesivir treatment is beneficial for preventing secondary infections, it may also attenuate the host's adaptive immune response to measles itself.
• Treatment timing is critical; late remdesivir intervention shows limited efficacy in preventing pathogen-specific antibody loss or modulating the MeV response.