Multiple Choice
B cells express a complement receptor that binds to C3b cleavage products, such as iC3b and C3dg. When a B cell with an antigen receptor that specifically recognizes that pathogen also has its complement receptor stimulated because the pathogen is opsonized with these C3 fragments, B cell activation is greatly enhanced. Due to this mechanism, B cells can be activated by much lower concentrations of antigen (in this case, the pathogen) than if the antigen is devoid of complement components. This mechanism functions to:
A) Ensure that pathogens are readily detected by the adaptive immune system before they replicate to high levels in the host
B) Prevent B cells from being activated in response to antigens that are not pathogens
C) Allow B cells to phagocytose the pathogen and help destroy it
D) Induce increased rounds of B cell replication to make more pathogen-specific B cells
E) Allow the B cell to block pathogen replication by interfering with multiple pathogen surface functions
Correct Answer:

Verified
Correct Answer:
Verified
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