An evaluation of various tissues in culture for isolation of eastern equine encephalitis virus.

This research focused on the evaluation of different tissue cultures for the isolation of the eastern equine encephalitis virus, and how effective they are compared to hens’ eggs and suckling mice – the common mediums used.

Background

• In 1936, it was discovered that embryonic chick tissue in fragment cultures could be used to detect the eastern equine encephalomyelitis virus, even in dilutions that couldn’t be detected by inoculating into the brains of mice and guinea pigs.
• This virus was found to multiply in other tissue cultures as well, causing a cytopathogenic effect on the cells – the virus effects cell health and functionality.
• Despite these findings, this method has not commonly been used for diagnostic or epidemiologic studies of the disease.

Objective

• The research aimed to evaluate the efficacy of tissue cultures for the isolation of the eastern equine encephalitis virus by comparing them with other isolation methods.

Research Methodology

• The researchers used various naturally and artificially infected specimens, including human, horse, pigeon, mouse brain tissues, and infected mosquitoes.
• There were several types of tissue cultures used in this study, among them trypsinized monkey kidney tissue, human amniotic tissue, human kidney cells, mouse brain cells, and more.
• The researchers also examined the neutralization of these agents using specific antisera and cultures of chick embryonic tissue.

Considerations

• The researchers had to consider how to preserve specimens; they preserved mosquitoes in a CO2 icebox, while they stored the remaining specimens as tissue fragments at -15°C or as supernatant fluids of suspensions in a CO2 chest.
• The research took into account the different nutrient mediums required for different tissue cultures. For instance, newborn mouse brain tissue had a different nutrient medium that contained bovine amniotic fluid, Hanks’ balanced salt solution, inactivated horse serum, and beef embryo extract.