Question

11. Viral antigens are loaded onto MHC class I receptors via the _______________ pathway.
A. intrinsic
B. extrinsic
C. endogenous
D. exogenous
E. complement

Answer 1

MHC I antigen presentation typically (considering cross-presentation ) involves the endogenous pathway of antigen processing.

• Endogenous pathway - e.g. proteolysis of antigens for binding to MHC I molecules
• The pathway is used to present cellular peptide fragments on the cell surface on MHC class I molecules.
• If a virus had infected the cell, viral peptides would also be presented, allowing the immune system to recognize and kill the infected cell.

ANSWER:

Viral antigens are loaded onto MHC class I receptors via the endogenous pathway.