The Infectious Cycle and Viral Diagnostics Flashcards
What is virus reproduction?
The sum total of all events that occur during the infectious cycle
What is the one-step growth curve?
A single reproduction cycle that occurs synchronously in every infected cell
What is a susceptible cell?
A cell that provides the receptors required for virus entry
Has a functional receptor for a given virus
What is a permissive cell?
A cell that is able to support virus reproduction when viral nucleic acid is introduced
Virus can be reproduced in a permissive cell
What is a monolayer?
A layer of cultured cells growing in a cell culture dish
What are primary-cell cultures?
Cell cultures prepared from animal tissues
These cultures include several cell types and have a limited life span usually no more than 5 to 20 cell divisions
What are continuous cell-lines?
Cultures of a single cell type that can be propagated indefinitely in culture
What are cytopathic effects?
The morphological changes induced in cells by viral infection
What is a virus titer?
The concentration of a virus in a sample
What are plaque-forming units (PFU) per milliliter?
A measure of virus infectivity
What is hemagglutination?
The linking of multiple red blood cells by virus particles resulting in a lattice basis of method to measure virus concentration
What is the eclipse period?
phase in which infectivity is lost when virions are disassembled after penetrating cells
What is the latent perioid?
how long it takes virus to get out of the cells once it is made
What is the multiplicity of infection?
number of infectious particles ADDED per cell
Formula:
MOI = Amount of virus (PFU) / # of cells
What are the 5 key steps to the viral infectious cycle ?
- Attachment and entry
- Translation
- Genome replication
- Assembly
- Release
Photo on chapter 3
What are two conditions that need to be satisfied to have a successful viral reproduction?
The cell HAS to be susceptible and permissive
What is the ONLY cell in which a virus can enter and be reproduced?
A susceptible and permissive cell
Are the infectious cycle and virus reproduction synonymous?
Yes (synonymous = same)
How do you know a cell has been infected with virus?
If they are susceptible and permissive, they will likely show CYTOPATHIC EFFECTS
Though, not ever cell will show cytopathic effects
What is a syncytia?
Large multinucleate cells
Multiple cell fusions of uninuclear cells
How is syncytia formed?
Syncytium formation is induced by viral infection
What are some virus examples of syncytia?
Herpesvirus Paramyxovirus Poxvirus Reovirus Retrovirus
What is the American Type Culture Collection (ATCC)?
A nonprofit organization
Established in 1925
Collects, stores, and distributes materials for R&D. These reference microorganisms and cell lines of any tissues.
Distributes to >150 countries