Viral immunity Flashcards
viruses are
obligate intracellular pathogens
viruses depend on
host proteins and machineries for replicattion
viruses can have as a few genes as
3-4
viruses can have as many genes as
hundred
types of viral DNA
ssRNA
dsRNA
ssDNA
dsDN
DNA is enclosed within
the capsid
viruses can be
cytopathic and non cytopathic
cytopathic viruses induce
cell autophagy or apoptosis
non-cytopathic
doe not destroy cell
name two cytopathic viruses
- polio
- herpes
- influenza
name as cell with a latent stage
herpes
name a non-cytopathic virus
Hep-B
name 4 methods that viruses use to break and enter humans
- intestinal route
- respiratory rout
- insect vector
- blood born
intestinal viruses
polio
polio
enter the body via sampling M cells
respiratory viruses
influenza and rhino viruses
influenza and rhino viruses
enter via epithelial cells in the airway
insect vector
dengue fever and west nile virus
blood born
invade through mucosa or following epithelial trauma
how to viruses enter the body- simple
by exploiting special molecules as receptors for invasion
viral tropism
most virus’ invade using receptors with restricted tissue expression patterns
name three receptors that HIV used to invade
CD4, CCR5, CD209
CD4 type of receptor
Ig superfamily
CCR5 type of receptor
chemokine
CD209 type of receptor
C-type lectin
viruses are the most common
recurring infection in humans
which type of viral infection causes the most mortality
zoonotic
HIV came from
chimpanzees in Africa
Hantavirus
rodents in S/N America
SARs coronavirus
Bats in china
innate response to virus’
- IFN
- complement
- NK cells
adaptive response to virus’
Cytotoxic T lymphocytes
B cells- antibodies
which type of immune cell is most abundant
CD8 T cells- population rises quickly after infection
CD4 T cell expansion
also occurs, but at a lower magnitude
neutralising antibodies
antibodies bind to virus’ preventing their uptake
when an antibody is bound to a virus was binds
C1q/r/s
C1q/r/s
complex couples antibody binding with the classical pathway
- analogous to MBL
NK cell mediated ADCC
antibodies bound to infected cell triggers NK cells to cytotoxically kill
epidemic
a disease that appears as new cases in a given human population, during a given period, at
a rate that substantially exceeds what is ‘expected’, based on recent evidence
an epidemic may be restricted to..
one locale (an outbreak), more general (an epidemic) or even global (pandemic)
pandemic
an epidemic that spreads through human populations across a large region e.g. a continent, or even worldwide