CCR7 and infection: However, HCMV infection did not upregulate another M1 marker tested, CD197 (also known as CCR7) at 72 h post infection (hpi), or the M2 marker CD206 at 48 hpi (Figure 1A,B), confirming that HCMV infection of monocytes stimulates a unique monocyte-to-macrophage differentiation process by upregulating select M1 and M2 characteristics required for the viral dissemination strategy.