Clinical relevance of such cellular interactions is suggested by the observed relationship between tumor-associated macrophages and CAR T cell activity in 10 patients with chemotherapy-refractory diffuse large B cell lymphomas treated with CD19-directed CAR T cells in the setting of a phase 1 dose-escalation study, in which remission status after CAR T cell therapy was negatively influenced by an increased infiltration with tumor-associated macrophages, as determined in tumor samples collected via core needle biopsies [151]. This evidence concerns the gene CD19 and neoplasm.