Interestingly, in a pre-clinical mouse model of B cell lymphomas, Ly6Clow monocytes (corresponding to the ncMO) (30) accumulated and showed high levels of immunosuppressive genes (PD-L1, PD-L2, Arg1, IDO1, and CD163) associated with suppression of T cell proliferation (31). Here, ARG1 is linked to B-cell non-Hodgkin lymphoma.