The body's own cells do not trigger the alternative pathway of complement system activation. Why is this?
A) Host cells produce convertase 3b which changes C3b into C3a that does not activate the complement pathway.
B) Molecules in host cell membranes bind regulatory proteins that will inactivate any C3b molecules that attach to the membrane.
C) C3b triggers the alternative pathway in prokaryotes but not in eukaryotes.
D) Molecules in host cell membranes bind regulatory proteins that will stimulate the binding of C3b molecules to bacterial cells.
E) Molecules in host cell membranes bind any MACs, deactivating them and preventing the activation of the alternative pathway.

Question

The body's own cells do not trigger the alternative pathway of complement system activation. Why is this?
A) Host cells produce convertase 3b which changes C3b into C3a that does not activate the complement pathway.
B) Molecules in host cell membranes bind regulatory proteins that will inactivate any C3b molecules that attach to the membrane.
C) C3b triggers the alternative pathway in prokaryotes but not in eukaryotes.
D) Molecules in host cell membranes bind regulatory proteins that will stimulate the binding of C3b molecules to bacterial cells.
E) Molecules in host cell membranes bind any MACs, deactivating them and preventing the activation of the alternative pathway.

Quizplus · Accepted Answer

Host cell membranes contain molecules that bind regulatory proteins, such as factor H, that inactivate any C3b molecules that attach to the membrane. This prevents host cells from triggering the alternative pathway of complement system activation.

The Body's Own Cells Do Not Trigger the Alternative Pathway