Fig 4   Infected cell treated with reverse transcriptase inhibitors plus protease inhibitor. In this situation the reverse transcriptase inhibitors are blocking further infection by HIV and the protease inhibitors are "downstream" of the pro virus and are blocking production of the virus. Because of phosphorylation by CK2 there is greatly increased possibility for viral resistance. Any virus that infects the cell must acquire resistance to the reverse transcriptase inhibitors to "leak" through the inhibitor block. Pro virus must become resistant to the protease inhibitor for virus to be produced.

This diagram can be compared to the diagram for infected cells treated by reverse transcriptase inhibitors plus CK2 inhibitor. Although in this situation, when there is no viral resistance, production of virus by infected cells can be completely blocked, because of CK2 phosphorylation there is continued risk of development of viral resistance and this risk increases over time and virus will be produced.