The authors noted an acute mobilization of the immune response in vivo, with a remarkable shrinkage of tumors upon PDT, a higher infiltration of tumors with CD4+ and CD8+ lymphocytes, a higher infiltration of tumor-associated macrophages (TAMs), and a polarization of these TAMs toward the antitumoral M1 subtype, as well as a strong abscopal effect. The gene discussed is CD8A; the disease is neoplasm.