Antigens And Immunogens

Question 1

The immunologically active region of an antigen is the …..

Answer 1

Epitope

Question 2

Molecules that display little or no immunogenicity include

Answer 2

Cytochrome C
Collagen

Question 3

A good immunogen is > ………..
A poor immunogen is < …………

Answer 3

100,000 Da
5000 - 10,000Da

Question 4

A good immunogen is > ………..
A poor immunogen is < …………

Answer 4

100,000 Da
5000 - 10,000Da

Question 5

What are the genes that may be lacking in a host preventing immunogen recognition

Answer 5

1. MHC gene
2. Genes for BCR and TCR
3. Immunoregulatory genes
4. Genes for coding specific antibodies

Question 6

What are adjuvant
List the functions of adjuvants

Answer 6

Adjuvant are substances that enhance the response of the immune system to.an antigen.

1. Antigen persistency is prolonged
2. Co stimulatory responses are enhanced
3. Local inflammation is increased
4. Proliferation of non specific lymphocytes

Question 7

Nucleic acid are poor immunogen but become better when

Answer 7

They are single stranded
Or
Complexed with protein

Question 8

Exogenous antigen can eventually become endogenous e.g

Answer 8

Intracellular virus

Question 9

What are the three properties of T-independent antigen

Answer 9

Polymeric
Polyclonal activation of B cells type I and II
Degradability

Question 10

What are superantigens

Answer 10

They are antigens capable of polyclonal activation of T cells.
Results from over activation of the immune system and subsequent release of biologically active cytokines by T cells

T cell dependent
Mostly associated with bacterial infection can be associated with virus and other organism
Example
Staphylococci toxins
Streptococci pyrogenic toxins