Biologics

Question 1

What are biologics

Answer 1

Monoclonal antibodies that are large in size- cant be made

Question 2

How do we make biologics

Answer 2

Recombinant DNA- plasmids in host cell

Question 3

What are the advantages and disadvantages of using E.coli as a host for making biologics

Answer 3

+ves-
*High expression levels possible
*Quick and cheap
*Can scale up to large fermentation culture
*Molecular biology well know

-ves-
*Unable to undertake post-translational modifications
*Pyrogenic- LPS on e.coli surface

Question 4

What are post-translational modifications

Answer 4

Covalent modifications of amino acids
Glycosylation and phosphorylation most common

Question 5

What is N-linked glycosylation

Answer 5

Transfer of oligosaccharide donor
-Asn-XXX-ser/Thr or Asn-XXX-ser where xxx is any AA except Pro
Aids protein folding and transport through cell

Question 6

What are glycoforms

Answer 6

Variations in glycosylation patterns
1 protein can give different:
*Stability
*Solubility
*Serum Half Life
*Biological activity
*Immunogenecity

Question 7

What type of cells do we used for recombinant DNA?

Answer 7

Eukaryotes- need glycosylation machinery
only eukaryotes can create the proteins needed

Can use chinese hamster overy cells, Human embryonic kidney cells

Question 8

What is hybridoma technology for monoclonal antibody production?

Answer 8

Mouse immunised with antigen
Isolation of antibody producing plasma B cells
Plasma cells mixed with myeloma and fused with PEG
Cells grow in a medium where only fused cells can grow
Fused cells showing high antibody production are expanded and grown in large number for antibody production

Question 9

What is a biosimilar

Answer 9

New biologic resulting from a repeat in the process of making a biologic
Same sequence but may have different properties