CD4 and neoplasm: The immunohistochemical assessment of the immune response in tumor tissue showed an increased number of CD4+ and CD8+ cells in both Ad6-d24-GM and Ad6wt groups compared to the PBS-treated group (p < 0.01 for CD4+ and CD8+ in both treatments compared to PBS), reflecting higher infiltration of T-lymphocytes in response to viral treatment (Figure 6).