Difference in response to mouse hepatitis virus among susceptible mouse strains

Area of Science:

• Immunology
• Virology
• Pathology

Background:

• Mouse hepatitis virus (MHV) is a significant pathogen in murine models.
• Understanding host susceptibility is crucial for studying viral pathogenesis.

Purpose of the Study:

• To investigate the differential susceptibility of DDD and CDF1 mice to a high-virulent mouse hepatitis virus (MHV).
• To elucidate the cellular and immunological mechanisms underlying this observed difference in response.

Main Methods:

• Intraperitoneal inoculation of mice with MHV.
• Survival time analysis and determination of 50% lethal doses.
• Virus titration in various organs (liver, blood, spleen).
• Immunofluorescence for viral antigen detection.
• Interferon production assays.
• Histopathological examination of liver tissues.
• In vitro culture of peritoneal macrophages for viral growth assessment.

Main Results:

• CDF1 mice exhibited significantly shorter survival times compared to DDD mice after MHV inoculation.
• Virus titers were substantially higher in the liver and blood of CDF1 mice.
• Viral antigen was more prominent in the liver sinusoidal lining cells of CDF1 mice.
• Interferon production and viral growth in macrophages were significantly higher in CDF1 mice.
• Liver lesions were more severe and widespread in CDF1 mice.

Conclusions:

• The susceptibility of macrophages and reticuloendothelial cells plays a critical role in determining the divergent response of mice to MHV.
• These cellular differences dictate the severity of disease and survival outcomes.