CCR2 and plasma cell myeloma: We present two examples – one of CCR2/CD192 (Figure 4g, h), a chemokine receptor expressed on monocytes (Tsou et al., 2007), and CD38 (Figure 4i, j), a glycoprotein expressed on the surface of multiple immune cell types (Ferrero and Malavasi, 2002), and a target of therapies for multiple myeloma (Dima et al., 2020; Sanchez et al., 2016).