A1

Question 1

Name antibody killing mechanisms for bacterial

1. bacterial toxins
2. bacteria in extracellular space
3. bacteria in plasma

Answer 1

1. cells with toxin receptors –> neutralization –> ingestion by macrophage
2. bacteria opsonized & ingested by macrophage
3. complement activation –> lysis & ingestion

Question 2

describe immunized donor antibody response (2y response)

Answer 2

frequency of antigen specific Bc decreases
IgG & IgA produced
affinity for antibody is higher than 1y
somatic hypermutation is higher vs 1y

Question 3

Name a problem with taking antibodies from serum

Answer 3

Serum contains lots of other proteins - this causes sensitivity: cross reactivity problems –> should purify: elute antibodies

Question 4

Name problems w/ polyclonal antibodies

- what is the solution

Answer 4

1. Different classes & isotypes of Ab present
2. ~different specificities against different parts of the molecule
3. ~contaminating antibodies that react with other proteins
4. Sometimes need mores specific & well characterised reagents
   - –> monoclonal antibodies were generated

Question 5

How are monoclonal antibodies generated?

Advantages of monoclonal antibodies (5)

Answer 5

B cell fused w/ tumor cell = immortal & antibody producing

1. Can be produced in large quantities without the need for repeated bleeding of animal
2. Bind specific epitope of an antigen
3. Exactly same Ig class and isotype
4. Can be highly purified
5. Allows in-depth analysis, w/out batch variation to quantify specific analytes and to treat patients

Question 6

Describe phage display production of monoclonal Abs

Answer 6

1. Isolate pop of genes encoding antibody variable region
2. Construct fusion protein of V region w/ bacteriophage coat protein
3. Cloning a random pop of V regions gives rise to a mix of bacteriophage: a phage displaying library
4. Select phage w/ desired V regions by specific binding to antigen