Comparative analyses of members of the Venezuelan equine encephalomyelitis virus complex.

This research studied the Venezuelan equine encephalomyelitis (VEE) virus complex, identifying distinctive characteristics of various strains through gel electrophoretic examination. Notably, while all tested viruses had identical core proteins, their envelope proteins differed among different strains, introducing potential new criteria for classifying these viruses.

Overview of the Research

• The research conducts comparative analyses of different strains selected from the Venezuelan equine encephalomyelitis (VEE) virus complex.
• The study uses polyacrylamide gel electrophoretic examination, a method that separates proteins based on their electrophoretic mobility, which is determined by the protein’s size and charge.
• The main objective is to identify any distinct strain-to-strain differences within the two virion envelope proteins present in VEE.

Key Findings

• The core protein, which is essential for the survival and reproduction of the virus, was found to be identical in all the VEE virus samples tested.
• However, a striking variation was identified among the strains in the patterns of the two envelope proteins, which are essential for the virus to infect host cells.
• The research detected five specific patterns that the virus strains could be classified into. These were labelled as alpha, beta, gamma, delta, and epsilon.

Implications and Significance

• One critical findings is that the subtype variant E of VEE exhibited only one envelope band (protein). This could be a unique feature.
• Contrarily, the epizootic subtypes I-A, I-B, I-C and the sylvatic subtype II viruses were found to contain at least two envelope proteins. The weight of these proteins varied according to the strain, but was not necessarily specific for an antigenic variety. Antigenic variety refers to the ability to induce an immune response.
• Overall, these findings broadly support the current serologic classification of the VEE complex, which is based on the reactions of antibodies in the serum. However, some inconsistencies were observed, hinting the classification could benefit from including biochemical criteria.
• The study suggests incorporating these variations in envelope proteins into the classification scheme, which could complement and enhance the current serological classification system based solely on immune response.