Question

Which of the following statements is true about the degradation of extracellular proteins?

a. The peptides produced will be delivered to CD8 T cells.
b. The peptides produced will be bound to MHC class I molecules.
c. The peptides produced will be found in a phagolysosome.
d. A & C
e. A, B, & C

Answer 1

c. The peptides produced will be found in a phagolysosome.

The peptides produced from the degradation of extracellular proteins by APCs are presented on MHC class II molecules and found in a phagolysosome, not delivered to CD8 T cells or bound to MHC class I molecules.

Step-by-step explanation:

The degradation of extracellular proteins by antigen-presenting cells (APCs) involves the phagocytosis of these proteins, followed by their processing within a phagolysosome.

The resulting peptides are presented on the cell surface in conjunction with MHC class II molecules, not MHC class I molecules. The peptides bound to MHC class II molecules are then recognized by CD4+ helper T cells rather than CD8+ cytotoxic T cells, which are typically associated with peptides presented by MHC class I molecules.

Therefore, the correct statement about the degradation of extracellular proteins is that the peptides produced will be found in a phagolysosome (option c).