Junín virus persistence in mice

Area of Science:

• Neurovirology
• Immunology
• Infectious Diseases

Background:

• Junín virus (JV) causes Argentine hemorrhagic fever, a severe zoonotic disease.
• Viral persistence in the central nervous system (CNS) is a potential factor in long-term sequelae.
• Understanding the host-pathogen dynamics in the neonatal CNS is crucial for disease management.

Purpose of the Study:

• To investigate the long-term viral persistence of Junín virus (JV) strain XJ in the brains of newborn mice.
• To determine the correlation between viral presence, neuropathology, and neutralizing antibody titres (NtAb) in surviving mice.

Main Methods:

• Intracerebral inoculation of newborn mice with Junín virus (JV) strain XJ.
• Monitoring of survival and clinical signs.
• Post-mortem analysis of brain tissue for viral RNA detection.
• Assessment of neuropathological changes (meningoencephalitis/encephalitis).
• Measurement of Junín virus (JV)-specific neutralizing antibody titres (NtAb).

Main Results:

• Newborn mice surviving intracerebral JV infection exhibited persistent viral presence in the brain up to 140 days post-infection (p.i.).
• Mild meningoencephalitis or encephalitis was observed in infected mice.
• Viral persistence in the brain did not correlate with the presence of neutralizing antibody titres (NtAb).

Conclusions:

• Junín virus (JV) can establish long-term persistence in the brain of neonatally infected mice.
• The development of neutralizing antibodies (NtAb) does not necessarily clear the virus from the CNS.
• Mild neuropathology correlates with viral presence, suggesting ongoing viral activity despite antibody presence.