Lecture 28 Flashcards
What is the first recorded use of vaccines?
Edward Jenner vaccinating James Phipps with cow pox to protect against small pox
This vaccine remains the most effective as it is the only vaccine which has managed to completely eradicate a virus
What is poliomyelitis?
A disease caused by the polio virus which can be prevented through vaccination achieved by use of live attenuated poliovirus or whole killed viruses
How can attenuated vaccines be produced?
The virus is grown under modified conditions to produce a strain that can no longer cause disease while retaining enough antigen similarity to the disease causing strain so that there is still proper immune education
How can recombinant virus be used in a new form of gene therapy?
A recombinant viral vector can be used to express an antigen in a recipient allowing for immunological gene therapy
What are subunit vaccines?
Vaccines which consist of one part of the virus only, this is typically the outer capsid
This includes the Hepatitis B vaccine where the surface antigen was used this was previously purified from the serum of chronically infected patients but is now produced by recombinant yeast
What is Gardasil?
This is a recombinant vaccine against HPV containing the non-infectious virus like particles of HPV types 16, 18, 6 and 11
The VLPs used in the vaccine are produced through the recombinant saccharomyces cerevisiae yeast and using aluminium hydroxyphosphate sulphate as an adjuvant
How does the antiviral drug acyclovir work?
It is used as a herpes simplex treatment and administered as a prodrug it requires one phosphorylation by a viral thymidine kinase followed by two subsequent phosphorylation’s by cellular enzymes to form the active drug this then acts to inhibit viral DNA synthesis by destabilising the DNA strands produced by the viral DNA polymerase
What are the antiviral agents that act against HIV replication?
Polymerase inhibitors
Assembly inhibitors
Entry (fusion inihibitors)
How do protease inhibitors act against HIV infection?
Usually the proteins that make up the HIV virion are made as a polyprotein which is cleaved by proteases to form mature infectious virus protease inhibitors like indinavir prevent this maturation stage from happening
How can fusion inhibitors act against HIV?
Induction of membrane fusion can occur at the cell surface requiring 2 receptors CD4 which is sufficient for viral binding and CCR which is required for infection
Fuzeon is a synthetic peptide that binds to part of gp41 and prevents transition to the fusion-active conformation during cell entry
