Related Experiment Videos
Characterization of genetically engineered mengoviruses in mice
J E Osorio1, S E Grossberg, A C Palmenberg
1Merial Limited, Athens, GA, USA.
Viral Immunology
|March 25, 2000
Summary
Shortened poly(C) tracts in mengoviruses attenuate virulence in adult mice, but not newborns. Host age and genetic background significantly influence viral pathogenicity, highlighting the role of immune competence.
Area of Science:
- Virology
- Immunology
- Genetics
Background:
- Mengovirus virulence is influenced by its 5' noncoding poly(C) tract length.
- Artificially shortened poly(C) tracts lead to significant viral attenuation in adult mice.
Purpose of the Study:
- To further investigate the relationship between poly(C) tract length and mengovirus virulence.
- To determine the impact of host age and genetic background on poly(C)-mediated attenuation.
Main Methods:
- Generation of mengoviruses with varying poly(C) tract lengths (e.g., C0, C13UC10, C44UC10).
- Infection of mice of different ages (newborn, adult) and genetic backgrounds (Swiss/ICR, BALB/c, C57BL/6, C3H strains).
- Assessment of viral pathogenicity, viremia levels, and host interferon response, including in immunosuppressed models.
Main Results:
- Short poly(C) tract viruses were attenuated in adult mice but virulent in newborn mice.
- Murine genotype significantly affected virulence; C57BL/6, C3H/Hej, and C3H/Hen mice showed differential susceptibility.
- Wild-type length poly(C) virus (vMwt) induced higher viremia and interferon levels than the attenuated vMC24.
- Immunosuppression reduced vMwt pathogenicity but did not affect vMC24 virulence.
Conclusions:
- Host age is critical for poly(C)-mediated attenuation of mengovirus.
- Murine genetic background plays a significant role in determining susceptibility to mengovirus infection.
- Endogenous immune components and host immune competence are key factors in mengovirus infection susceptibility.