Figure 1. Low dose, metronomic cyclophosphamide decreases Tregs, increases activated NK cells and modulates the myeloid population in tumor-burdened mice.

Data reflect two weeks of CY treatment, twice weekly (i.p.) or 5 doses weekly (p.o.) dosing in the syngeneic CT26 tumor model. (A) Frequency of Tregs in response to increasing doses of CY (i.p.). (B) Frequency of intratumoral Tregs following either p.o. or i.p. CY dosing. (C) Frequency of CD8+ T cells in response to increasing doses of CY (i.p.). (D) NK cell activity in response to increasing doses of CY (i.p.). (E) Frequency of intratumoral PMN following 40 mg/kg CY (i.p.) treatment. (F) Gating scheme for Ly6C+ CD11b+ myeloid cells and TAMs. (G) Frequency and MHCII expression of Ly6C+ CD11b+ myeloid cells in the tumor in response to 40 mg/kg CY. (H) Frequency of intratumoral MHCII^lo-hi Ly6C- CD11b+ TAMs in response to 40 mg/kg CY. (I) Frequency of eosinophils following 40 mg/kg CY (i.p.) treatment. Data show the mean ± SEM. ^* indicates P ≤ 0.05, ^** P ≤ 0.01, ^*** P ≤ 0.001, and ^**** P ≤ 0.0001. Representative graphs shown of one (A–D, I), or at least two (E–H) independent experiments.