CD8A and neoplasm: With regard to the mechanism of the therapeutic effect, in the above mentioned GBM ATV-NDV vaccination study [140], vaccine-induced immune effects had been documented at various levels: (i) significant increase of skin delayed-type hypersensitivity tumor-reactive responses, (ii) significant increase in blood-circulatory tumor-reactive memory T cells and (iii) significant increase in CD8+ tumor-infiltrating T cells (TILs) that had infiltrated across the blood-brain barrier into secondary GBM tumors [140].