Repurposing Virus Like Particles in Materials Design

Question 1

Describe how infectious P22 is assembled vs P22 VLP

Answer 1

infectious P22

• portal, scaffold and coat proteins assemble to a procaspid –> scaffold flips inside out + coat protein is lost + DNA is packaged –> gp4 + gp10 + gp26 + gp9 close the portal and spring loads the virus

P22 VLP

• CP + SP –> empty caspid (420 CPs)

Question 2

how is P22 VLP made to be a contrast agent for MRI?

Answer 2

serine –> cysteine –> initiator binds –> reacts with AEMA via ATRP (atom transfer radical polymerization) –> polymer formation –> contrast agen (Gd-DTPA-NCS) binds to the amine on AEMA

Question 3

what are the benefits vs challenges of using P22 VLP as a contrast agent for MRI?

Answer 3

benefits

• fewer side effects of a smaller and targeted dose of contrast agent
• better contrast –> better to spot things (because high concentration/multivalency)

challenges

• immunity:
• inflammation –> aggitate the problem via immune-mediated toxicity
• one time use - macrophages –> immune mediated toxicity
• macrophages - decrease dose + contrast agent will be in macrophages and not where you want it
• cost
• ethics

Question 4

how is P22 VLP made to be a vaccine to stimulate CD8+ T cells?

Answer 4

truncated N-term of scaffold fused with NP from influenza or M/M2 from RSV

Question 5

what is the benefits and challenges of using P22 VLP to be a vaccine to stimulate CD8+ T cells?

Answer 5

benefits

• show immune system Ags it wouldn’t see –> mount a cytolytic response –> need to kill virus-infected (intracellular) cells to end infection + Abs are sometimes worse for disease (e.g. Ab-dependent enhancement in Dengue virus)
• conserved Ags –> won’t mutate away (more pantropic – good for seasonal respiratory viruses)

challenges

• make non-neutralizing Abs
• NP might mutate away
• one vector one virus – immunity against vector
• long term immunity
• can’t use for bacteria – want a Th17 immune response, not Th1

Question 6

how is P22 VLP made to act as a metabalon?

Answer 6

truncated scaffold fused with multiple pathway enzymes –> cluster using positive dendrimer –> concentrates it

Question 7

what are the benefits and challenges of using P22 VLP to act as a metabalon?

Answer 7

benefits

• improve reaction –> per mL have more
• stability of enzymes
• force multiple enzymes in same space
• know the stoichometry
• modify coat to move the virus where you want
• if shell is stable, protect enzymes from proteases
• control the environment
• biodegradable
• lattic: concentrate enzymes without having them mess up each other

Question 8

what are some potential usages of P22 VLP metabalon?

Answer 8

• break down oil
• convert CO2 –> O2
• produce hydrogen fuel