Isolation, Cultivation, and Identification of Viruses

Growing Bacteriophages in the Lab

can be grown in liquid suspension

can be grown on solid media

plaque method: clearings and turbidity

plaque forming units (PFU)

Growing Animal Viruses in the Lab

In Living Animals

inoculation for diagnosis

some human viruses can't be grown in animals: AIDS

recent studies with mice have been used to study replication

In Embryonated Eggs

viral growth

death of embryo

embryo cell damage

pocks and lesions on egg membrane

why asked if allergic to eggs before receiving vaccination

In Cell Structures

preferred type of growth medium

more convenient to work with

cytopathic effect (CPE): cells of monolayer deteriorate as they multiply

Lines

Primary Cell Lines

derived from tissue slices

die out after a few generations

diploid cell lines from human enbryos can be used for 100 generations

Continuous Cell Lines

indefinite number of generations

immortal cell lines

HeLa cell line cancer from woman who died in 1951

major problem is that cell lines must be kept free of microbial contamination

a lot of samples are sent to central labs to avoid above problem

Viral Identification

need electron microscope

Serological method = Western blotting commonly used

IDed by reaction with antibodies

restriction fragment length polymorphisms (RFLPs)

Polymerase Chain Reaction (PCR): SARS and West Nile Virus IDed