Final answer:
Effector cell differentiation in the primary immune response involves generating both effector and memory cells, with a delayed and lower level of antibody production. In the secondary response, memory cells rapidly differentiate into effector cells, leading to a quicker, stronger immune attack with high-affinity antibodies and thus providing effective immunity.
Step-by-step explanation:
Effector Cell Differentiation: Primary vs Secondary Response
The adaptive immune response is characterized by a primary and secondary response. During the primary response, naïve B cells and T cells are activated upon first exposure to an antigen. This activation leads to the production of effector cells, which combat the pathogen, and memory cells, which are retained for long-term immunity. Effector T cells help in cell-mediated immunity, while B cells differentiate into plasma cells that produce antibodies.
In the subsequent secondary response, these memory cells quickly recognize and respond to the previously encountered antigen without the delay observed in the primary response. This dramatically faster and more vigorous response is due to the memory cells' ability to rapidly differentiate into a large number of effector cells, resulting in a higher antibody production and stronger immune attack. This secondary response often prevents the re-establishing pathogen from causing disease symptoms, which is a key aspect of the body's immunological memory.
The same principles apply to both T cell and B cell responses. Notably, the secondary response produces antibodies with a higher affinity for their target and at higher concentrations. Plasma cells generated during the secondary response also tend to have a longer lifespan, sustaining elevated levels of antibodies over time compared to the primary response.