Question

LDL particles can be oxidized after prolonged circulation. Macrophages can absorb these oxidized LDL particles using so-called scavenger receptors onto the plasma membrane. Why can this cause macrophages to be converted into foam cells? a. Oxidized cholesterol molecules are toxic to the macrophages. b. Oxidized cholesterol molecules feedback does not inhibit cholesterol synthesis in the macrophages, so the macrophages are overfilled with cholesterol. c. Oxidized cholesterol molecules, unlike non-oxidized cholesterol, cannot be excreted from the macrophages, so the macrophages are overfilled with cholesterol. d. The expression of the scavenger receptors feedback-is not inhibited by intracellular cholesterol, which is why the macrophages are overfilled with cholesterol. e. The scavenger receptors can absorb many LDL particles at a time, which is why the macrophages are overfilled with cholesterol.

Answer 1

Option e.

These scavenger receptors act as "Pattern recognition receptors" (PRR's) on macrophages and are responsible for recognizing and binding to oxidized LDL, which in turn promotes the formation of foam cells through internalization of these lipoproteins.