Fig. 2.

Intervention of HCQ and CQ in the exogenous pathway of antigen presentation: Exogenous antigens that are taken up either by endocytosis or phagocytosis requires fusion with lysosomes for the process of degradation. Finally, the degraded antigen fragments are loaded onto the MHC class II molecules for antigen presentation. Lysosomotropic drugs like HCQ and CQ accumulate inside the lysosome and these drugs potentially increase the pH inside and disrupt lysosomal functions