The inside is now outside. The cell has sent a sampling of its inner life, bound in the correct frame, to be surveyed by the immune system. When a CD8 cell comes by, sniffing the cell surface, it will find a large selection of peptides from the interior of a cell loaded on its surface—including, of course, the peptide from the virus. And only if that foreign peptide is presented by the self MHC (the altered self) will it trigger an immune response, killing the infected cell.
