Question

Compare and contrast primary and secondary (anamnestic) immune responses and explain the cytological basis for the anamnestic response. Include duration of lag phase, immunoglobins involved, and magnitude and duration of response in your comparison.

Answer 1

Primary Response	Secondary Response
Mostly long lag phase (days or weeks)	Very short lag phase (2-3 days)
Amount of antibody produced is low	Amount of antibody produced is high
Duration of response is less (antibody level decline shortly)	Duration of response is longer (antibody remain longer)
IgM is mainly involved	IgG is mainly involved

The secondary response of the immune system towards any particular antigen is much faster than the primary immune response. Memory B cells and memory T4 cells developed during the first infection will persist in our body during the rest of our life. These are able to produce a fast response when the second infection arises. So they will generate anamnestic response within 2-3 days of infection.