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A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins
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A Miniaturized Glycan Microarray Assay for Assessing Avidity and Specificity of Influenza A Virus Hemagglutinins

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Structural changes and aggregation of human influenza virus

Jason N Campbell1, Richard M Epand, Paul S Russo

  • 1Department of Chemistry, Louisiana State University, Baton Rouge 70803-1804, USA.

Biomacromolecules
|September 14, 2004
PubMed

Insights

Lowering pH causes intact human influenza virus particles to rapidly increase in size and aggregate. This pH-induced aggregation is a key factor in understanding influenza virus behavior in different environments.

Area of Science:

  • Virology
  • Biophysics
  • Materials Science

Background:

  • Human influenza virus (PR-8 and X-31 strains) structural changes were investigated.
  • Understanding virus behavior under varying pH conditions is crucial for virology and drug development.

Purpose of the Study:

  • To investigate the in vitro pH-induced structural and aggregation changes in intact human influenza virus particles.
  • To characterize the dynamic light scattering changes associated with pH reduction.

Main Methods:

  • Dynamic light scattering (DLS) was used to study virus particle size and aggregation.
  • Scattering profiles were analyzed at different pH levels (7.4 and 5.0).

Main Results:

  • Reducing pH from 7.4 to 5.0 caused a significant increase in light scattering intensity.
  • Virus particles showed increased polydispersity and aggregation at lower pH.
  • Scattering profiles at pH 5.0 closely matched models of aggregated spheres, not isolated particles.

Conclusions:

  • Intact influenza virus particles exhibit an instantaneous increase in hydrodynamic size upon acidification.
  • Acidification induces virus particle aggregation over minutes to hours.
  • Virus particles are non-uniform and prone to aggregation at reduced pH.

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