To determine if the cells derived from CCR2+HSCs that extravasate from intracranial tumor to the draining lymph nodes have the capacity to cross-prime endogenous T cells, tumor-bearing mice received intra-tumor injection of either DsRed+HSCs, DsRed+CCR2−HSCs, or DsRed+CCR2+HSCs and treated with PD-1. The gene discussed is CCR2; the disease is neoplasm.