CD8A and infection: For example, liposome NPs modified with dextran and encapsulated in pH‐sensitive ovalbumin were used to target the cytosol of DCs.[121] This system successfully activated antigen‐specific cellular immunity through the MHC‐I pathway, and ultimately enhanced the activity of CD8+ T cytotoxic cells, serving to counter infection and to generate sustained memory T cells against recurrent infection.[122]