Step I immunology question

[MudPhud20XX]

Hi all, can anyone help me with this q?

During the epidemic of H. influenza meningitis that occurred in infants in the US prior to 1990, a vaccine preparation consisting of the polyribitol phosphate capsule of the type B organism was used in trials. The vaccine was administered with an adjuvant and injected intramuscularly in three doses over the courses of 5 months. At the end of the trial period, which would be the predominant isotype of antibody produced in response to this vaccination?

 

[cs24]

I would guess IgG, but not sure.

 

[dfib slim]

I would guess IgM. Polysaccharide antigen unable to activate T cells.

 

[aspiringmd1015]

read below.

 

[dfib slim]

I always thought adjuvants were things like aluminum or oils added to the vaccine to promote inflammation and conjugates were the polysacharride + protein.

 

[Transposony]

I always thought adjuvants were things like aluminum or oils added to the vaccine to promote inflammation and conjugates were the polysacharride + protein.

Exactly right.
Adjuvants are just baits for APCs to come and taste the antigen.

 

[MudPhud20XX]

The answer is IgG. I also chose IgM. Looks like the polysaccardie antigen does not activate T cell thus no class switching. Thank you for the input!

 

[cs24]

I would guess IgM. Polysaccharide antigen unable to activate T cells.

Whoops you're right, I completely jumped right to conjugated vaccines when I saw HiB and didn't read "adjuvant"

The answer is IgG. I also chose IgM. Looks like the polysaccardie antigen does not activate T cell thus no class switching. Thank you for the input!

Okay now I'm confused...

 

[dfib slim]

The answer is IgG. I also chose IgM. Looks like the polysaccardie antigen does not activate T cell thus no class switching. Thank you for the input!

Your statement is contradictory.

 

[aspiringmd1015]

has to be igM