Step 1: How do viral vaccines work?

[IkramKhaliq]

This might be a really stupid question (forgive me )

If we were to administer the MMR vaccine to a patient, what would the best effector cells be?
a) B cells
b) CD8 cells
c) CD4 cells

Given that the vaccine is a live attenuated virus, I assumed (correctly) that the best effector cells would be CD8 cells. But then I got confused. Since viral antigens are presented on MHC-I and would logically activate only CD8 T-cells, how do we get an antibody response to the MMR vaccine? I'm assuming we do because we measure IgG for proof of vaccination. What activates the helper T cells to allow class-switching?

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[Oligodinero]

APCs (Macrophages, dendritic cells, and Bcells) will find bits of virus, phagocytize and present viral antigens to CD4 Thelpers which will then secrete IL-4, TGF-B, etc. to induce class switching from IgM to other, better classes. The viral antigens the APCs find most likely are liberated after the virally-infected host cell is lysed by either the virus, NK cells, or Tkiller cells. T helpers are activated in their interaction with the surface of APCs.

-at least that's my understanding of it.

 

[IkramKhaliq]

APCs (Macrophages, dendritic cells, and Bcells) will find bits of virus, phagocytize and present viral antigens to CD4 Thelpers which will then secrete IL-4, TGF-B, etc. to induce class switching from IgM to other, better classes. The viral antigens the APCs find most likely are liberated after the virally-infected host cell is lysed by either the virus, NK cells, or Tkiller cells. T helpers are activated in their interaction with the surface of APCs.

-at least that's my understanding of it.

Thanks! I had a very faulty concept that viral particles are only presented on MHC-I.

Follow-up question: which cells help provide the immunity to these viruses in the future?

The CD8 cells will be the most important effector cells against the vaccine, but the B cells (and their immunoglobulins) will provide immunity in the future?

 

[deleted859689]

Thanks! I had a very faulty concept that viral particles are only presented on MHC-I.

Follow-up question: which cells help provide the immunity to these viruses in the future?

The CD8 cells will be the most important effector cells against the vaccine, but the B cells (and their immunoglobulins) will provide immunity in the future?

Memory T-cells. Go watch Cells at Work bro.