While additional studies have linked CXCL2-CXCR2 and CCL2-CCR2 signaling to MDSC trafficking across tumor types 52,56-58, we did not directly test the necessity of any single chemokine in this work (e.g., by neutralization or receptor knockout), which we acknowledged as a limitation and a priority for future investigation. The gene discussed is CCR2; the disease is neoplasm.