Question

Why is a polysaccharide vaccine not considered to produce long lived immunity with future protection against infection?

A.It does not stimulate the innate immune system
B.It only stimulates the production of IgM and no memory
C.It does not stimulate the adaptive immune system
D.Class switching is only seen in adults

Answer 1

A polysaccharide vaccine does not produce long-lived immunity because it only stimulates the production of IgM antibodies, does not involve the activation of T cells and the production of memory B cells, and does not induce class switching in B cells.

Step-by-step explanation:

A polysaccharide vaccine is not considered to produce long-lived immunity with future protection against infection for several reasons:

1. It only stimulates the production of IgM antibodies, which are short-lived and do not provide long-term immune memory. This means that the immune response generated by the vaccine fades over time.
2. The immune response to a polysaccharide vaccine is T cell-independent, which means it does not involve the activation of T cells and the production of memory B cells. Memory B cells are crucial for a strong and rapid secondary immune response upon re-exposure to the pathogen.
3. Polysaccharide vaccines do not induce class switching in B cells, which is necessary for the production of different types of antibodies, including IgG, that provide long-term protection.