Blocking of in vitro and in vivo susceptibility to mouse hepatitis virus

Area of Science:

• Virology
• Immunology
• Cell Biology

Background:

• Mouse hepatitis virus (MHV) infection poses a significant threat to susceptible mouse populations.
• Understanding host-pathogen interactions is crucial for developing effective antiviral strategies.

Purpose of the Study:

• To investigate the potential of concanavalin A (Con A) as a prophylactic agent against MHV infection.
• To elucidate the mechanisms by which Con A confers resistance to MHV.

Main Methods:

• Mice and cultured macrophages were pretreated with concanavalin A (Con A) in vivo and in vitro.
• Mice were infected with MHV, and mortality rates were assessed.
• Macrophage populations were analyzed for susceptibility to MHV infection.
• Mediators from Con A-treated spleen cells were used to assess resistance transfer.

Main Results:

• Con A pretreatment significantly reduced mortality in MHV-infected mice from 100% to less than 40%.
• Con A induced an inflammatory response and increased macrophage recruitment to the inoculation site.
• Con A-treated macrophages exhibited reduced susceptibility to MHV infection.
• Mediators from Con A-treated spleen cells conferred resistance to normally susceptible macrophages.

Conclusions:

• Concanavalin A pretreatment can convert genetically susceptible mice and macrophages to a phenotypically resistant state against MHV.
• The protective effect of Con A involves inducing inflammation, increasing macrophage numbers, and altering macrophage susceptibility.
• Con A-derived mediators offer a potential therapeutic avenue for conferring antiviral resistance.