Related Experiment Videos
Dengue virions and antigens in brain and serum of infected mice
Abstract:
The temporal relationships of the production of infectious dengue-2 virus and its antigens were investigated in intracerebrally infected suckling mice. Infectious virus, a slowly sedimenting noninfectious hemagglutinin (SHA), and a noninfectious soluble complement-fixing antigen (SCF) were found in the brain. Serum contained high concentrations of SCF antigen relative to infectivity when compared to SCF to infectivity ratios in the brain. Degradation of virions by Tween-80 and ether produced two antigens with sedimentation characteristics similar to the noninfectious antigens occurring naturally in infected tissues. However, the virionderived SHA differed from native SHA when examined by electron microscopy and by equilibrium centrifugation in cesium chloride. Virion-derived SCF (as well as the virions and both SHA antigens) was denatured by sodium lauryl sulfate (SLS) and 2-mercaptoethanol (2-ME), whereas native SCF retained its complement-fixing activity. SLS and 2-ME treatment of dengue-1 and dengue-2 sucrose-acetone antigens increased their serotypic specificity. The hemagglutinin present in sucrose-acetone antigens was predominantly native SHA.
Insights
This study investigated infectious dengue-2 virus and its antigens in mice. It found differences between naturally occurring and virion-derived antigens, impacting diagnostic specificity.
Area of Science:
- Virology
- Immunology
- Molecular Biology
Background:
- Dengue virus research is crucial for understanding viral pathogenesis.
- Characterizing viral antigens aids in vaccine development and diagnostics.
Purpose of the Study:
- To investigate the temporal production of infectious dengue-2 virus and its antigens in suckling mice.
- To compare naturally occurring noninfectious antigens with those derived from virions.
Main Methods:
- Intracerebral infection of suckling mice with dengue-2 virus.
- Analysis of infectious virus, soluble hemagglutinin (SHA), and soluble complement-fixing (SCF) antigens in brain and serum.
- Degradation of virions using Tween-80 and ether.
- Characterization of antigens using electron microscopy, cesium chloride equilibrium centrifugation, and sodium lauryl sulfate (SLS)/2-mercaptoethanol (2-ME) treatment.
Main Results:
- Infectious virus, native SHA, and native SCF were detected in the brain.
- Serum showed higher SCF antigen to infectivity ratios than brain tissue.
- Virion-derived antigens differed from native antigens in sedimentation and stability.
- Native SCF retained complement-fixing activity after SLS/2-ME treatment, unlike virion-derived SCF.
- SLS/2-ME treatment enhanced serotypic specificity of dengue-1 and dengue-2 sucrose-acetone antigens.
- Hemagglutinin in sucrose-acetone antigens was primarily native SHA.
Conclusions:
- Native and virion-derived dengue antigens exhibit distinct properties.
- Understanding these differences is vital for accurate dengue virus diagnostics and vaccine design.
- The stability and specificity of dengue antigens can be modulated by chemical treatments.